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Title: On the Genesis of Species
Author: St. George Mivart
Release Date: March 14, 2007 [EBook #20818]
Language: English
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ON THE GENESIS OF SPECIES.
[Illustration]
ON THE
GENESIS OF SPECIES.
BY
ST. GEORGE MIVART, F.R.S.
London:
MACMILLAN AND CO.
1871.
[_The Right of Translation and Reproduction is reserved._]
LONDON:
R. CLAY, SONS, AND TAYLOR, PRINTERS,
BREAD STREET HILL.
* * * * *
TO
SIR HENRY HOLLAND, BART., M.D.,
F.R.S., D.C.L., ETC. ETC.
MY DEAR SIR HENRY,
In giving myself the pleasure to dedicate, as I now do, this work to you,
it is not my intention to identify you with any views of my own advocated
in it.
I simply avail myself of an opportunity of paying a tribute of esteem and
regard to my earliest scientific friend--the first to encourage me in
pursuing the study of nature.
I remain,
MY DEAR SIR HENRY,
Ever faithfully yours,
ST. GEORGE MIVART.
7, NORTH BANK, REGENT'S PARK,
_December 8, 1870._
{vii}
* * * * *
CONTENTS.
CHAPTER I.
_INTRODUCTORY_
The problem of the genesis of species stated.--Nature of its probable
solution.--Importance of the question.--Position here defended.--Statement
of the DARWINIAN THEORY.--Its applicability to details of geographical
distribution; to rudimentary structures; to homology; to mimicry,
&c.--Consequent utility of the theory.--Its wide acceptance.--Reasons for
this other than, and in addition to, its scientific value. Its
simplicity.--Its bearing on religious questions.--_Odium theologicum_ and
_odium antitheologicum_.--The antagonism supposed by many to exist between
it and theology neither necessary nor universal.--Christian authorities in
favour of evolution.--Mr. Darwin's "Animals and Plants under
Domestication."--Difficulties of the Darwinian theory enumerated ... _Page_
1
CHAPTER II.
_THE INCOMPETENCY OF "NATURAL SELECTION" TO ACCOUNT FOR THE INCIPIENT
STAGES OF USEFUL STRUCTURES._
Mr. Darwin supposes that Natural-Selection acts by slight
variations.--These must be useful at once.--Difficulties as to the giraffe;
as to mimicry; as to the heads of flat-fishes; as to the origin and
constancy of the vertebrate, limbs; as to whalebone; as to the young
kangaroo; as to sea-urchins; as to certain processes of {viii}
metamorphosis; as to the mammary gland; as to certain ape characters; as to
the rattlesnake and cobra; as to the process of formation of the eye and
ear; as to the fully developed condition of the eye and ear; as to the
voice; as to shell-fish; as to orchids; as to ants.--The necessity for the
simultaneous modification of many individuals.--Summary and conclusion ...
_Page_ 23
CHAPTER III.
_THE CO-EXISTENCE OF CLOSELY SIMILAR STRUCTURES OF DIVERSE ORIGIN._
Chances against concordant variations.--Examples of discordant
ones.--Concordant variations not unlikely on a non-Darwinian evolutionary
hypothesis.--Placental and implacental mammals.--Birds and
reptiles.--Independent origins of similar sense organs.--The ear.--The
eye.--Other coincidences.--Causes besides Natural Selection produce
concordant variations in certain geographical regions.--Causes besides
Natural Selection produce concordant variations in certain zoological and
botanical groups.--There are homologous parts not genetically
related.--Harmony in respect of the organic and inorganic worlds.--Summary
and conclusion ... _Page_ 63
CHAPTER IV.
_MINUTE AND GRADUAL MODIFICATIONS._
There are difficulties as to minute modifications, even if not
fortuitous.--Examples of sudden and considerable modifications of different
kinds.--Professor Owen's view.--Mr. Wallace.--Professor Huxley.--Objections
to sudden changes.--Labyrinthodont.--Potto.--Cetacea.--As to origin of
bird's wing.--Tendrils of climbing plants.--Animals once supposed to be
connecting links.--Early specialization of
structure.--Macrauchenia.--Glyptodon.--Sabre-toothed tiger.--Conclusion ...
_Page_ 97
{ix}
CHAPTER V.
_AS TO SPECIFIC STABILITY._
What is meant by the phrase "specific stability;" such stability to be
expected _a priori_, or else considerable changes at once.--Rapidly
increasing difficulty of intensifying race characters; alleged causes of
this phenomenon; probably an internal cause co-operates.--A certain
definiteness in variations.--Mr. Darwin admits the principle of specific
stability in certain cases of unequal variability.--The goose.--The
peacock.--The guinea fowl.--Exceptional causes of variation under
domestication.--Alleged tendency to reversion.--Instances.--Sterility of
hybrids.--Prepotency of pollen of same species, but of different
race.--Mortality in young gallinaceous hybrids.--A bar to intermixture
exists somewhere.--Guinea-pigs.--Summary and conclusion ... _Page_ 113
CHAPTER VI.
_SPECIES AND TIME._
Two relations of species to time.--No evidence of past existence of
minutely intermediate forms when such might be expected _a priori_.--Bats,
Pterodactyles, Dinosauria, and Birds.--Ichthyosauria, Chelonia, and
Anoura.--Horse ancestry.--Labyrinthodonts and Trilobites.--Two subdivisions
of the second relation of species to time.--Sir William Thomson's
views.--Probable period required for ultimate specific evolution from
primitive ancestral forms.---Geometrical increase of time required for
rapidly multiplying increase of structural differences.--Proboscis
monkey.--Time required for deposition of strata necessary for Darwinian
evolution.--High organization of Silurian forms of life.--Absence of
fossils in oldest rocks.--Summary and conclusion ... _Page_ 128
CHAPTER VII.
_SPECIES AND SPACE._
The geographical distribution of animals presents difficulties.--These not
insurmountable in themselves; harmonize with other
difficulties.--Fresh-water fishes.--Forms common to Africa and India; to
Africa and South America; to China and Australia; to North America and {x}
China; to New Zealand and South America; to South America and Tasmania; to
South America and Australia.--Pleurodont lizards.--Insectivorous
mammals.--Similarity of European and South American frogs.--Analogy between
European salmon and fishes of New Zealand, &c.--An ancient Antarctic
continent probable.--Other modes of accounting for facts of
distribution.--Independent origin of closely similar forms.--Conclusion ...
_Page_ 144
CHAPTER VIII.
_HOMOLOGIES._
Animals made up of parts mutually related in various ways.--What homology
is.--Its various kinds.--Serial homology.--Lateral homology.--Vertical
homology.--Mr. Herbert Spencer's explanations.--An internal power
necessary, as shown by facts of comparative anatomy.---Of teratology.--M.
St. Hilaire.--Professor Burt Wilder.--Foot-wings.--Facts of pathology.--Mr.
James Paget.--Dr. William Budd.--The existence of such an internal power of
individual development diminishes the improbability of an analogous law of
specific origination ... _Page_ 155
CHAPTER IX.
_EVOLUTION AND ETHICS._
The origin of morals an inquiry not foreign to the subject of this
book.--Modern utilitarian view as to that origin.--Mr. Darwin's speculation
as to the origin of the abhorrence of incest.--Cause assigned by him
insufficient.--Care of the aged and infirm opposed by "Natural Selection;"
also self-abnegation and asceticism.--Distinctness of the ideas right and
useful.--Mr. John Stuart Mill.--Insufficiency of "Natural Selection" to
account for the origin of the distinction between duty and
profit.--Distinction of moral acts into material and formal.--No ground{xi}
for believing that formal morality exists in brutes.--Evidence that it does
exist in savages.--Facility with which savages may be
misunderstood.--Objections as to diversity of customs.--Mr. Button's review
of Mr. Herbert Spencer.--Anticipatory character of morals.--Sir John
Lubbock's explanation.--Summary and conclusion ... _Page_ 188
CHAPTER X.
_PANGENESIS._
A provisional hypothesis supplementing "Natural Selection."--Statement of
the hypothesis.--Difficulty as to multitude of gemmules.--As to certain
modes of reproduction.--As to formations without the requisite
gemmules.--Mr. Lewes and Professor Delpino.--Difficulty as to developmental
force of gemmules.--As to their spontaneous fission.--Pangenesis and
Vitalism.--Paradoxical reality.--Pangenesis scarcely superior to anterior
hypotheses.--Buffon.--Owen.--Herbert Spencer.--Gemmules as mysterious as
"physiological units."--Conclusion ... _Page_ 208
CHAPTER XI.
_SPECIFIC GENESIS._
Review of the statements and arguments of preceding chapters.--Cumulative
argument against predominant action of "Natural Selection."--Whether
anything positive as well as negative can be enunciated.--Constancy of laws
of nature does not necessarily imply constancy of specific
evolution.--Possible exceptional stability of existing epoch.--Probability
that an internal cause of change exists.--Innate powers somewhere must be
accepted.--Symbolism of molecular action under vibrating impulses.
Professor Owen's statement.--Statement of the Author's view.--It avoids the
difficulties which oppose "Natural Selection."--It harmonizes apparently
conflicting conceptions.--Summary and conclusion ... _Page_ 220 [Page xii]
CHAPTER XII.
_THEOLOGY AND EVOLUTION._
Prejudiced opinions on the subject.--"Creation" sometimes denied from
prejudice.--The unknowable.--Mr. Herbert Spencer's objections to theism; to
creation.--Meanings of term "creation."--Confusion from not distinguishing
between "primary" and "derivative" creation.--Mr. Darwin's
objections.--Bearing of Christianity on evolution.--Supposed opposition,
the result of a misconception.--Theological authority not opposed to
evolution.--St. Augustin.--St. Thomas Aquinas.--Certain consequences of
want of flexibility of mind.--Reason and imagination.--The first cause and
demonstration.--Parallel between Christianity and natural theology.--What
evolution of species is.--Professor Agassiz.--Innate powers must be
recognized.--Bearing of evolution on religious belief.--Professor
Huxley.--Professor Owen.--Mr. Wallace.--Mr. Darwin.--_A priori_ conception
of Divine action.--Origin of man.--Absolute creation and dogma.--Mr.
Wallace's view.--A supernatural origin for man's body not necessary.--Two
orders of being in man.--Two modes of origin.--Harmony of the physical,
hyperphysical, and supernatural.--Reconciliation of science and religion as
regards evolution.--Conclusion ... _Page_ 243
INDEX ... _Page_ 289
{xiii}
LIST OF ILLUSTRATIONS.
Leaf Butterfly in flight and repose (_from Mr. A. Wallace's "Malay
Archipelago"_) ... 31
Walking-Leaf Insect ... 35
Pleuronectidæ, with the peculiarly placed eye in different positions (_from
Dr. Traquair's paper in Linn. Soc. Trans., 1865_) ... 37, 166
Mouth of Whale (_from Professor Owen's "Odontography"_) ... 40
Four plates of Baleen seen obliquely from within (_from Professor Owen's
"Odontography"_) ... 41
Dugong ... 41, 175
Echinus or Sea Urchin ... 43, 167
Pedicellariæ of Echinus very much enlarged ... 44
Rattlesnake ... 49
Cobra (_from Sir Andrew Smith's "Southern Africa"_) ... 50
Wingbones of Pterodactyle, Bat, and Bird (_from Mr. Andrew Murray's
"Geographical Distribution of Mammals"_) ... 64, 130, 157
Skeleton of Flying-Dragon ... 65, 158
Centipede (_from a specimen in the Museum of the Royal College of
Surgeons_) ... 66, 159
Teeth of Urotrichus and Perameles ... 68
The Archeopteryx (_from Professor Owen's "Anatomy of Vertebrata"_) ... 73,
132
{xiv}
Cuttle-Fish ... 75, 141
Skeleton of Ichthyosaurus ... 78, 107, 132, 177
Cytheridea Torosa (_from Messrs. Brady and Robertson's paper in Ann. and
Mag. of Nat. Hist., 1870_) ... 79
A Polyzoon, with Bird's-head processes ... 80
Bird's-head processes greatly enlarged ... 81
Antechimis Minutissimus and Mus Delicatulus (_from Mr. Andrew Murray's
"Geographical Distribution of Mammals"_) ... 82
Outlines of Wings of Butterflies of Celebes compared with those of allied
species elsewhere ... 86
Great Shielded Grasshopper ... 89
The Six-shafted Bird of Paradise ... 90
The Long-tailed Bird of Paradise ... 91
The Red Bird of Paradise ... 92
Horned Flies ... 93
The Magnificent Bird of Paradise ... 93
_(The above seven figures are from Mr. A. Wallace's "Malay Archipelago"_)
Much enlarged horizontal Section of the Tooth of a Labyrinthodon (_from
Professor Owen's "Odontography"_) ... 104
Hand of the Potto (_from life_) ... 105
Skeleton of Plesiosaurus ... 106, 133
The Aye-Aye (_from Trans, of Zool. Soc._) ... 108
Dentition of Sabre-toothed Tiger (_from Professor Owen's "Odontography"_)
... 110
Trilobite ... 135, 171
Inner side of Lower Jaw of Pleurodont Lizard (_from Professor Owen's
"Odontography"_) ... 148
Solenodon (_from Berlin Trans._) ... 149
Tarsal Bones of Galago and Cheirogaleus (_from Proc. Zool. Soc._) ... 159
Squilla ... 160
Parts of the Skeleton of the Lobster ... 161 [Page xv]
Spine of Galago Allenii (_from Proc. Zool. Soc._) ... 162
Vertebrae of Axolotl (_from Proc. Zool. Soc._) ... 165
Annelid undergoing spontaneous fission ... 169, 211
Aard-Vark (_Orycteropus capensis_) ... 174
Pangolin (_Manis_) ... 175
Skeleton of Manus and Pes of a Tailed Batrachian (_from Professor
Gegenbaur's "Tarsus and Carpus"_) ... 178
Flexor Muscles of Hand of Nycticetus (_from Proc. Zool. Soc._) ... 180
The Fibres of Corti ... 279
{1}
* * * * *
THE GENESIS OF SPECIES.
CHAPTER I.
_INTRODUCTORY._
The problem of the genesis of species stated.--Nature of its probable
solution.--Importance of the question.--Position here
defended.--Statement of the DARWINIAN THEORY.--Its applicability to
details of geographical distribution; to rudimentary structures; to
homology; to mimicry, &c.--Consequent utility of the theory.--Its wide
acceptance.--Reasons for this, other than, and in addition to, its
scientific value.--Its simplicity.--Its bearing on religious
questions.--_Odium theologicum_ and _odium antitheologicum_.--The
antagonism supposed by many to exist between it and theology neither
necessary nor universal.--Christian authorities in favour of
evolution.--Mr. Darwin's "Animals and Plants under
Domestication."--Difficulties of the Darwinian theory enumerated.
The great problem which has so long exercised the minds of naturalists,
namely, that concerning the origin of different kinds of animals and
plants, seems at last to be fairly on the road to receive--perhaps at no
very distant future--as satisfactory a solution as it can well have.
But the problem presents peculiar difficulties. The birth of a "species"
has often been compared with that of an "individual." The origin, however,
of even an individual animal or plant (that which determines an embryo to
evolve itself,--as, _e.g._, a spider rather than a beetle, a rose-plant {2}
rather than a pear) is shrouded in obscurity. _A fortiori_ must this be the
case with the origin of a "species."
Moreover, the analogy between a "species" and an "individual" is a very
incomplete one. The word "individual" denotes a concrete whole with a real,
separate, and distinct existence. The word "species," on the other hand,
denotes a peculiar congeries of characters, innate powers and qualities,
and a certain nature realized indeed in individuals, but having no separate
existence, except ideally as a thought in some mind.
Thus the birth of a "species" can only be compared metaphorically, and very
imperfectly, with that of an "individual."
Individuals as _individuals_, actually and directly produce and bring forth
other individuals; but no "congeries of characters" no "common nature" _as
such_, can directly bring forth another "common nature," because, _per se_,
it has no existence (other than ideal) apart from the individuals in which
it is manifested.
The problem then is, "by what combination of natural laws does a new
'common nature' appear upon the scene of realized existence?" _i.e._ how is
an individual embodying such new characters produced?
For the approximation we have of late made towards the solution of this
problem, we are mainly indebted to the invaluable labours and active brains
of Charles Darwin and Alfred Wallace.
Nevertheless, important as has been the impulse and direction given by
those writers to both our observations and speculations, the solution will
not (if the views here advocated are correct) ultimately present that
aspect and character with which it has issued from the hands of those
writers.
Neither, most certainly, will that solution agree in appearance or
substance with the more or less crude conceptions which have been put forth
by most of the opponents of Messrs. Darwin and Wallace. [Page 3]
Rather, judging from the more recent manifestations of thought on opposite
sides, we may expect the development of some _tertium quid_--the resultant
of forces coming from different quarters, and not coinciding in direction
with any one of them.
As error is almost always partial truth, and so consists in the
exaggeration or distortion of one verity by the suppression of another
which qualifies and modifies the former, we may hope, by the synthesis of
the truths contended for by various advocates, to arrive at the one
conciliating reality.
Signs of this conciliation are not wanting: opposite scientific views,
opposite philosophical conceptions, and opposite religious beliefs, are
rapidly tending by their vigorous conflict to evolve such a systematic and
comprehensive view of the genesis of species as will completely harmonize
with the teachings of science, philosophy, and religion.
To endeavour to add one stone to this temple of concord, to try and remove
a few of the misconceptions and mutual misunderstandings which oppose
harmonious action, is the aim and endeavour of the present work. This aim
it is hoped to attain, not by shirking difficulties, but analysing them,
and by endeavouring to dig down to the common root which supports and
unites diverging stems of truth.
It cannot but be a gain when the labourers in the three fields above
mentioned, namely, science, philosophy, and religion, shall fully recognize
this harmony. Then the energy too often spent in futile controversy, or
withheld through prejudice, may be profitably and reciprocally exercised
for the mutual benefit of all.
Remarkable is the rapidity with which an interest in the question of
specific origination has spread. But a few years ago it scarcely occupied
the minds of any but naturalists. Then the crude theory put forth by
Lamarck, and by his English interpreter the author of the "Vestiges of
Creation," had rather discredited than helped on a belief in organic
evolution--a belief, that is, in new kinds being produced from older {4}
ones by the ordinary and constant operation of natural laws. Now, however,
this belief is widely diffused. Indeed, there are few drawing-rooms where
it is not the subject of occasional discussion, and artisans and schoolboys
have their views as to the permanence of organic forms. Moreover, the
reception of this doctrine tends actually, though by no means necessarily,
to be accompanied by certain beliefs with regard to quite distinct and very
momentous subject-matter. So that the question of the "Genesis of Species"
is not only one of great interest, but also of much importance.
But though the calm and thorough consideration of this matter is at the
present moment exceedingly desirable, yet the actual importance of the
question itself as to its consequences in the domain of theology has been
strangely exaggerated by many, both of its opponents and supporters. This
is especially the case with that form of the evolution theory which is
associated with the name of Mr. Darwin; and yet neither the refutation nor
the demonstration of that doctrine would be necessarily accompanied by the
results which are hoped for by one party and dreaded by another.
The general theory of evolution has indeed for some time past steadily
gained ground, and it may be safely predicted that the number of facts
which can be brought forward in its support will, in a few years, be vastly
augmented. But the prevalence of this theory need alarm no one, for it is,
without any doubt, perfectly consistent with strictest and most orthodox
Christian theology. Moreover, it is not altogether without obscurities, and
cannot yet be considered as fully demonstrated.
The special Darwinian hypothesis, however, is beset with certain scientific
difficulties, which must by no means be ignored, and some of which, I
venture to think, are absolutely insuperable. What Darwinism or "Natural
Selection" is, will be shortly explained; but before doing so, I think {5}
it well to state the object of this book, and the view taken up and
defended in it. It is its object to maintain the position that "Natural
Selection" acts, and indeed must act, but that still, in order that we may
be able to account for the production of known kinds of animals and plants,
it requires to be supplemented by the action of some other natural law or
laws as yet undiscovered.[1] Also, that the consequences which have been
drawn from Evolution, whether exclusively Darwinian or not, to the
prejudice of religion, by no means follow from it, and are in fact
illegitimate.
The Darwinian theory of "Natural Selection" may be shortly stated
thus:[2]--
Every kind of animal and plant tends to increase in numbers in a
geometrical progression.
Every kind of animal and plant transmits a general likeness, with
individual differences, to its offspring.
Every individual may present minute variations of any kind and in any
direction.
Past time has been practically infinite.
Every individual has to endure a very severe struggle for existence, owing
to the tendency to geometrical increase of all kinds of animals and plants,
while the total animal and vegetable population (man and his agency
excepted) remains almost stationary.
Thus, every variation of a kind tending to save the life of the individual
possessing it, or to enable it more surely to propagate its kind, will in
the long run be preserved, and will transmit its favourable peculiarity to
some of its offspring, which peculiarity will thus become intensified {6}
till it reaches the maximum degree of utility. On the other hand,
individuals presenting unfavourable peculiarities will be ruthlessly
destroyed. The action of this law of Natural Selection may thus be well
represented by the convenient expression "survival of the fittest."[3]
Now this conception of Mr. Darwin's is perhaps the most interesting theory,
in relation to natural science, which has been promulgated during the
present century. Remarkable, indeed, is the way in which it groups together
such a vast and varied series of biological[4] facts, and even paradoxes,
which it appears more or less clearly to explain, as the following
instances will show. By this theory of "Natural Selection," light is thrown
on the more singular facts relating to the geographical distribution of
animals and plants; for example, on the resemblance between the past and
present inhabitants of different parts of the earth's surface. Thus in
Australia remains have been found of creatures closely allied to kangaroos
and other kinds of pouched beasts, which in the present day exist nowhere
but in the Australian region. Similarly in South America, and nowhere else,
are found sloths and armadillos, and in that same part of the world have
been discovered bones of animals different indeed from existing sloths and
armadillos, but yet much more nearly related to them than to any other
kinds whatever. Such coincidences between the existing and antecedent
geographical distribution of forms are numerous. Again, "Natural Selection"
serves to explain the circumstance that often in adjacent islands we find
animals closely resembling, and appearing to represent, each other; while
if certain of these islands show signs (by depth of surrounding sea or what
not) of more ancient separation, the animals inhabiting them exhibit a {7}
corresponding divergence.[5] The explanation consists in representing the
forms inhabiting the islands as being the modified descendants of a common
stock, the modification being greatest where the separation has been the
most prolonged.
"Rudimentary structures" also receive an explanation by means of this
theory. These structures are parts which are apparently functionless and
useless where they occur, but which represent similar parts of large size
and functional importance in other animals. Examples of such "rudimentary
structures" are the foetal teeth of whales, and of the front part of the
jaw of ruminating quadrupeds. These foetal structures are minute in size,
and never cut the gum, but are reabsorbed without ever coming into use,
while no other teeth succeed them or represent them in the adult condition
of those animals. The mammary glands of all male beasts constitute another
example, as also does the wing of the apteryx--a New Zealand bird utterly
incapable of flight, and with the wing in a quite rudimentary condition
(whence the name of the animal). Yet this rudimentary wing contains bones
which are miniature representatives of the ordinary wing-bones of birds of
flight. Now, the presence of these useless bones and teeth is explained if
they may be considered as actually being the inherited diminished
representatives of parts of large size and functional importance in the
remote ancestors of these various animals.
Again, the singular facts of "homology" are capable of a similar
explanation. "Homology" is the name applied to the investigation of those
profound resemblances which have so often been found to underlie
superficial differences between animals of very different form and habit.
Thus man, the horse, the whale, and the bat, all have the pectoral limb,
whether it be the arm, or fore-leg, or paddle, or wing, formed on
essentially the same type, though the number and proportion of parts may{8}
more or less differ. Again, the butterfly and the shrimp, different as they
are in appearance and mode of life, are yet constructed on the same common
plan, of which they constitute diverging manifestations. No _a priori_
reason is conceivable why such similarities should be necessary, but they
are readily explicable on the assumption of a genetic relationship and
affinity between the animals in question, assuming, that is, that they are
the modified descendants of some ancient form--their common ancestor.
That remarkable series of changes which animals undergo before they attain
their adult condition, which is called their process of development, and
during which they more or less closely resemble other animals during the
early stages of the same process, has also great light thrown on it from
the same source. The question as to the singularly complex resemblances
borne by every adult animal and plant to a certain number of other animals
and plants--resemblances by means of which the adopted zoological and
botanical systems of classification have been possible--finds its solution
in a similar manner, classification becoming the expression of a
genealogical relationship. Finally, by this theory--and as yet by this
alone--can any explanation be given of that extraordinary phenomenon which
is metaphorically termed _mimicry_. Mimicry is a close and striking, yet
superficial resemblance borne by some animal or plant to some other,
perhaps very different, animal or plant. The "walking leaf" (an insect
belonging to the grasshopper and cricket order) is a well-known and
conspicuous instance of the assumption by an animal of the appearance of a
vegetable structure (see illustration on p. 35); and the bee, fly, and
spider orchids are familiar examples of a converse resemblance. Birds,
butterflies, reptiles, and even fish, seem to bear in certain instances a
similarly striking resemblance to other birds, butterflies, reptiles, and
fish, of altogether distinct kinds. The explanation of this matter which
"Natural Selection" offers, as to animals, is that certain varieties of {9}
one kind have found exemption from persecution in consequence of an
accidental resemblance which such varieties have exhibited to animals of
another kind, or to plants; and that they were thus preserved, and the
degree of resemblance was continually augmented in their descendants. As to
plants, the explanation offered by this theory might perhaps be that
varieties of plants which presented a certain superficial resemblance in
their flowers to insects, have thereby been helped to propagate their kind,
the visit of certain insects being useful or indispensable to the
fertilization of many flowers.
We have thus a whole series of important facts which "Natural Selection"
helps us to understand and co-ordinate. And not only are all these diverse
facts strung together, as it were, by the theory in question; not only does
it explain the development of the complex instincts of the beaver, the
cuckoo, the bee, and the ant, as also the dazzling brilliancy of the
humming-bird, the glowing tail and neck of the peacock, and the melody of
the nightingale; the perfume of the rose and the violet, the brilliancy of
the tulip and the sweetness of the nectar of flowers; not only does it help
us to understand all these, but serves as a basis of future research and of
inference from the known to the unknown, and it guides the investigator to
the discovery of new facts which, when ascertained, it seems also able to
co-ordinate.[6] Nay, "Natural Selection" seems capable of application not
only to the building up of the smallest and most insignificant organisms,
but even of extension beyond the biological domain altogether, so as
possibly to have relation to the stable equilibrium of the solar system{10}
itself, and even of the whole sidereal universe. Thus, whether this theory
be true or false, all lovers of natural science should acknowledge a deep
debt of gratitude to Messrs. Darwin and Wallace, on account of its
practical utility. But the utility of a theory by no means implies its
truth. What do we not owe, for example, to the labours of the Alchemists?
The emission theory of light, again, has been pregnant with valuable
results, as still is the Atomic theory, and others which will readily
suggest themselves.
With regard to Mr. Darwin (with whose name, on account of the noble
self-abnegation of Mr. Wallace, the theory is in general exclusively
associated), his friends may heartily congratulate him on the fact that he
is one of the few exceptions to the rule respecting the non-appreciation of
a prophet in his own country. It would be difficult to name another living
labourer in the field of physical science who has excited an interest so
widespread, and given rise to so much praise, gathering round him, as he
has done, a chorus of more or less completely acquiescing disciples,
themselves masters in science, and each the representative of a crowd of
enthusiastic followers.
Such is the Darwinian theory of "Natural Selection," such are the more
remarkable facts which it is potent to explain, and such is the reception
it has met with in the world. A few words now as to the reasons for the
very widespread interest it has awakened, and the keenness with which the
theory has been both advocated and combated.
The important bearing it has on such an extensive range of scientific
facts, its utility, and the vast knowledge and great ingenuity of its
promulgator, are enough to account for the heartiness of its reception by
those learned in natural history. But quite other causes have concurred to
produce the general and higher degree of interest felt in the theory beside
the readiness with which it harmonizes with biological facts. These latter
could only be appreciated by physiologists, zoologists, and botanists;
whereas the Darwinian theory, so novel and so startling, has found a {11}
cloud of advocates and opponents beyond and outside the world of physical
science.
In the first place, it was inevitable that a great crowd of half-educated
men and shallow thinkers should accept with eagerness the theory of
"Natural Selection," or rather what they think to be such (for few things
are more remarkable than the way in which it has been misunderstood), on
account of a certain characteristic it has in common with other theories;
which should not be mentioned in the same breath with it, except, as now,
with the accompaniment of protest and apology. We refer to its remarkable
simplicity, and the ready way in which phenomena the most complex appear
explicable by a cause for the comprehension of which laborious and
persevering efforts are not required, but which may be represented by the
simple phrase "survival of the fittest." With nothing more than this, can,
on the Darwinian theory, all the most intricate facts of distribution and
affinity, form, and colour, be accounted for; as well the most complex
instincts and the most admirable adjustments, such as those of the human
eye and ear. It is in great measure then, owing to this supposed
simplicity, and to a belief in its being yet easier and more simple than it
is, that Darwinism, however imperfectly understood, has become a subject
for general conversation, and has been able thus widely to increase a
certain knowledge of biological matters; and this excitation of interest in
quarters where otherwise it would have been entirely wanting, is an
additional motive for gratitude on the part of naturalists to the authors
of the new theory. At the same time it must be admitted that a similar
"simplicity"--the apparently easy explanation of complex phenomena--also
constitutes the charm of such matters as hydropathy and phrenology, in the
eyes of the unlearned or half-educated public. It is indeed _the_ charm of
all those seeming "short cuts" to knowledge, by which the labour of
mastering scientific details is spared to those who yet believe that {12}
without such labour they can attain all the most valuable results of
scientific research. It is not, of course, for a moment meant to imply that
its "simplicity" tells at all against "Natural Selection," but only that
the actual or supposed possession of that quality is a strong reason for
the wide and somewhat hasty acceptance of the theory, whether it be true or
not.
In the second place, it was inevitable that a theory appearing to have very
grave relations with questions of the last importance and interest to man,
that is, with questions of religious belief, should call up an army of
assailants and defenders. Nor have the supporters of the theory much
reason, in many cases, to blame the more or less unskilful and hasty
attacks of adversaries, seeing that those attacks have been in great part
due to the unskilful and perverse advocacy of the cause on the part of some
of its adherents. If the _odium theologicum_ has inspired some of its
opponents, it is undeniable that the _odium antitheologicum_ has possessed
not a few of its supporters. It is true (and in appreciating some of Mr.
Darwin's expressions it should never be forgotten) that the theory has been
both at its first promulgation and since vehemently attacked and denounced
as unchristian, nay, as necessarily atheistic; but it is not less true that
it has been made use of as a weapon of offence by irreligious writers, and
has been again and again, especially in continental Europe, thrown, as it
were, in the face of believers, with sneers and contumely. When we
recollect the warmth with which what he thought was Darwinism was advocated
by such a writer as Professor Vogt, one cause of his zeal was not far to
seek--a zeal, by the way, certainly not "according to knowledge;" for few
conceptions could have been more conflicting with true Darwinism than the
theory he formerly maintained, but has since abandoned, viz. that the men
of the Old World were descended from African and Asiatic apes, while,
similarly, the American apes were the progenitors of the human beings of
the New World. The cause of this palpable error in a too eager disciple{13}
one might hope was not anxiety to snatch up all or any arms available
against Christianity, were it not for the tone unhappily adopted by this
author. But it is unfortunately quite impossible to mistake his meaning and
intention, for he is a writer whose offensiveness is gross, while it is
sometimes almost surpassed by an amazing shallowness. Of course, as might
fully be expected, he adopts and reproduces the absurdly trivial objections
to absolute morality drawn from differences in national customs.[7] And he
seems to have as little conception of the distinction between "formally"
moral actions and those which are only "materially" moral, as of that
between the _verbum mentale_ and the _verbum oris_. As an example of his
onesidedness, it may be remarked that he compares the skulls of the
American monkeys (_Cebus apella_ and _C. albifrons_) with the intention of
showing that man is of several distinct species, because skulls of
different men are less alike than are those of these two monkeys; and he
does this regardless of how the skulls of domestic animals (with which it
is far more legitimate to compare races of men than with wild kinds),
_e.g._ of different dogs or pigeons, tell precisely in the opposite
direction. Regardless also of the fact that perhaps no genus of monkeys is
in a more unsatisfactory state as to the determination of its different
kinds than the genus chosen by him for illustration. This is so much the
case that J. A. Wagner (in his supplement to Schreber's great work on
Beasts) at first included all the kinds in a single species.
As to the strength of his prejudice and his regretable coarseness, one
quotation will be enough to display both. Speaking of certain early
Christian missionaries, he says,[8] "It is not so very improbable that the
new religion, before which the flourishing Roman civilization relapsed into
a state of barbarism, should have been introduced by people in whose {14}
skulls the anatomist finds simious characters so well developed, and in
which the phrenologist finds the organ of veneration so much enlarged. I
shall, in the meanwhile, call these simious narrow skulls of Switzerland
'Apostle skulls,' as I imagine that in life they must have resembled the
type of Peter, the Apostle, as represented in Byzantine-Nazarene art."
In face of such a spirit, can it be wondered at that disputants have grown
warm? Moreover, in estimating the vehemence of the opposition which has
been offered, it should be borne in mind that the views defended by
religious writers are, or should be, all-important in their eyes. They
could not be expected to view with equanimity the destruction in many minds
of "theology, natural and revealed, psychology, and metaphysics;" nor to
weigh with calm and frigid impartiality arguments which seemed to them to
be fraught with results of the highest moment to mankind, and, therefore,
imposing on their consciences strenuous opposition as a first duty. Cool
judicial impartiality in them would have been a sign perhaps of
intellectual gifts, but also of a more important deficiency of generous
emotion.
It is easy to complain of the onesidedness of many of those who oppose
Darwinism in the interest of orthodoxy; but not at all less patent is the
intolerance and narrow-mindedness of some of those who advocate it,
avowedly or covertly, in the interest of heterodoxy. This hastiness of
rejection or acceptance, determined by ulterior consequences believed to
attach to "Natural Selection," is unfortunately in part to be accounted for
by some expressions and a certain tone to be found in Mr. Darwin's
writings. That his expressions, however, are not always to be construed
literally is manifest. His frequent use metaphorically of the expressions,
"contrivance," for example, and "purpose," has elicited, from the Duke of
Argyll and others, criticisms which fail to tell against their {15}
opponent, because such expressions are, in Mr. Darwin's writings, merely
figurative--metaphors, and nothing more.
It may be hoped, then, that a similar looseness of expression will account
for passages of a directly opposite tendency to that of his theistic
metaphors.
Moreover, it must not be forgotten that he frequently uses that absolutely
theological term, "the Creator," and that he has retained in all the
editions of his "Origin of Species" an expression which has been much
criticised. He speaks "of life, with its several powers, having been
originally breathed by the Creator into a few forms, or into one."[9] This
is merely mentioned in justice to Mr. Darwin, and by no means because it is
a position which this book is intended to support. For, from Mr. Darwin's
usual mode of speaking, it appears that by such divine action he means a
supernatural intervention, whereas it is here contended that throughout the
whole process of physical evolution--the first manifestation of life
included--_supernatural_ action is assuredly not to be looked for.
Again, in justice to Mr. Darwin, it may be observed that he is addressing
the general public, and opposing the ordinary and common objections of
popular religionists, who have inveighed against "Evolution" and "Natural
Selection" as atheistic, impious, and directly conflicting with the dogma
of creation.
Still, in so important a matter, it is to be regretted that he did not take
the trouble to distinguish between such merely popular views and those
which repose upon some more venerable authority. Mr. John Stuart Mill has
replied to similar critics, and shown that the assertion that his
philosophy is irreconcilable with theism is unfounded; and it would have
been better if Mr. Darwin had dealt in the same manner with some of his
assailants, and shown the futility of certain of their objections when {16}
viewed from a more elevated religious standpoint. Instead of so doing, he
seems to adopt the narrowest notions of his opponents, and, far from
endeavouring to expand them, appears to wish to endorse them, and to lend
to them the weight of his authority. It is thus that Mr. Darwin seems to
admit and assume that the idea of "creation" necessitates a belief in an
interference with, or dispensation of, natural laws, and that "creation"
must be accompanied by arbitrary and unorderly phenomena. None but the
crudest conceptions are placed by him to the credit of supporters of the
dogma of creation, and it is constantly asserted that they, to be
consistent, must offer "creative fiats" as explanations of physical
phenomena, and be guilty of numerous other such absurdities. It is
impossible, therefore, to acquit Mr. Darwin of at least a certain
carelessness in this matter; and the result is, he has the appearance of
opposing ideas which he gives no clear evidence of having ever fully
appreciated. He is far from being alone in this, and perhaps merely takes
up and reiterates, without much consideration, assertions previously
assumed by others. Nothing could be further from Mr. Darwin's mind than
any, however small, intentional misrepresentation; and it is therefore the
more unfortunate that he should not have shown any appreciation of a
position opposed to his own other than that gross and crude one which he
combats so superfluously--that he should appear, even for a moment, to be
one of those, of whom there are far too many, who first misrepresent their
adversary's view, and then elaborately refute it; who, in fact, erect a
doll utterly incapable of self-defence and then, with a flourish of
trumpets and many vigorous strokes, overthrow the helpless dummy they had
previously raised.
This is what many do who more or less distinctly oppose theism in the
interests, as they believe, of physical science; and they often represent,
amongst other things, a gross and narrow anthropomorphism as the necessary
consequence of views opposed to those which they themselves advocate. {17}
Mr. Darwin and others may perhaps be excused if they have not devoted much
time to the study of Christian philosophy; but they have no right to assume
or accept, without careful examination, as an unquestioned fact, that in
that philosophy there is a necessary antagonism between the two ideas,
"creation" and "evolution," as applied to organic forms.
It is notorious and patent to all who choose to seek, that many
distinguished Christian thinkers have accepted and do accept both ideas,
_i.e._ both "creation" and "evolution."
As much as ten years ago, an eminently Christian writer observed: "The
creationist theory does not necessitate the perpetual search after
manifestations of miraculous powers and perpetual 'catastrophes.' Creation
is not a miraculous interference with the laws of nature, but the very
institution of those laws. Law and regularity, not arbitrary intervention,
was the patristic ideal of creation. With this notion, they admitted
without difficulty the most surprising origin of living creatures, provided
it took place by _law_. They held that when God said, 'Let the waters
produce,' 'Let the earth produce,' He conferred forces on the elements of
earth and water, which enabled them naturally to produce the various
species of organic beings. This power, they thought, remains attached to
the elements throughout all time."[10] The same writer quotes St. Augustine
and St. Thomas Aquinas, to the effect that, "in the institution of nature
we do not look for miracles, but for the laws of nature."[11] And, again,
St. Basil,[12] speaks of the continued operation of natural laws in the
production of all organisms. [Page 18]
So much for writers of early and mediæval times. As to the present day, the
Author can confidently affirm that there are many as well versed in
theology as Mr. Darwin is in his own department of natural knowledge, who
would not be disturbed by the thorough demonstration of his theory. Nay,
they would not even be in the least painfully affected at witnessing the
generation of animals of complex organization by the skilful artificial
arrangement of natural forces, and the production, in the future, of a
fish, by means analogous to those by which we now produce urea.
And this because they know that the possibility of such phenomena, though
by no means actually foreseen, has yet been fully provided for in the old
philosophy centuries before Darwin, or even before Bacon, and that their
place in the system can be at once assigned them without even disturbing
its order or marring its harmony.
Moreover, the old tradition in this respect has never been abandoned,
however much it may have been ignored or neglected by some modern writers.
In proof of this it may be observed that perhaps no post-mediæval
theologian has a wider reception amongst Christians throughout the world
than Suarez, who has a separate section[13] in opposition to those who
maintain the distinct creation of the various kinds--or substantial
forms--of organic life.
But the consideration of this matter must be deferred for the present, and
the question of evolution, whether Darwinian or other, be first gone into.
It is proposed, after that has been done, to return to this subject (here
merely alluded to), and to consider at some length the bearing of
"Evolution," whether Darwinian or non-Darwinian, upon "Creation and
Theism."
Now we will revert simply to the consideration of the theory of "Natural
Selection" itself.
{19}
Whatever may have hitherto been the amount of acceptance that this theory
has met with, all, I think, anticipated that the appearance of Mr. Darwin's
large and careful work on "Animals and Plants under Domestication" could
but further increase that acceptance. It is, however, somewhat
problematical how far such anticipations will be realized. The newer book
seems to add after all but little in support of the theory, and to leave
most, if not all, its difficulties exactly where they were. It is a
question, also, whether the hypothesis of "Pangenesis"[14] may not be found
rather to encumber than to support the theory it was intended to subserve.
However, the work in question treats only of domestic animals, and probably
the next instalment will address itself more vigorously and directly to the
difficulties which seem to us yet to bar the way to a complete acceptance
of the doctrine.
If the theory of Natural Selection can be shown to be quite insufficient to
explain any considerable number of important phenomena connected with the
origin of species, that theory, as _the_ explanation, must be considered as
provisionally discredited.
If other causes than Natural (including sexual) Selection can be proved to
have acted--if variation can in any cases be proved to be subject to
certain determinations in special directions by other means than Natural
Selection, it then becomes probable _a priori_ that it is so in others, and
that Natural Selection depends upon, and only supplements, such means, {20}
which conception is opposed to the pure Darwinian position.
Now it is certain, _a priori_, that variation is obedient to some law and
therefore that "Natural Selection" itself must be capable of being subsumed
into some higher law; and it is evident, I believe, _a posteriori_, that
Natural Selection is, at the very least, aided and supplemented by some
other agency.
Admitting, then, organic and other evolution, and that new forms of animals
and plants (new species, genera, &c.) have from time to time been evolved
from preceding animals and plants, it follows, if the views here advocated
are true, that this evolution has not taken place by the action of "Natural
Selection" _alone_, but through it (amongst other influences) aided by the
concurrent action of some other natural law or laws, at present
undiscovered; and probably that the genesis of species takes place partly,
perhaps mainly, through laws which may be most conveniently spoken of as
special powers and tendencies existing in each organism; and partly through
influences exerted on each by surrounding conditions and agencies organic
and inorganic, terrestrial and cosmical, among which the "survival of the
fittest" plays a certain but subordinate part.
The theory of "Natural Selection" may (though it need not) be taken in such
a way as to lead men to regard the present organic world as formed, so to
speak, _accidentally_, beautiful and wonderful as is confessedly the
hap-hazard result. The same may perhaps be said with regard to the system
advocated by Mr. Herbert Spencer, who, however, also relegates "Natural
Selection" to a subordinate _rôle_. The view here advocated, on the other
hand, regards the whole organic world as arising and going forward in one
harmonious development similar to that which displays itself in the growth
and action of each separate individual organism. It also regards each such
separate organism as the expression of powers and tendencies not to be {21}
accounted for by "Natural Selection" alone, or even by that together with
merely the direct influence of surrounding conditions.
The difficulties which appear to oppose themselves to the reception of
"Natural Selection" or "the survival of the fittest," as the one
explanation of the origin of species, have no doubt been already considered
by Mr. Darwin. Nevertheless, it may be worth while to enumerate them, and
to state the considerations which appear to give them weight; and there is
no doubt but that a naturalist so candid and careful as the author of the
theory in question, will feel obliged, rather than the reverse, by the
suggestion of all the doubts and difficulties which can be brought against
it.
What is to be brought forward may be summed up as follows:--
That "Natural Selection" is incompetent to account for the incipient stages
of useful structures.
That it does not harmonize with the co-existence of closely similar
structures of diverse origin.
That there are grounds for thinking that specific differences may be
developed suddenly instead of gradually.
That the opinion that species have definite though very different limits to
their variability is still tenable.
That certain fossil transitional forms are absent, which might have been
expected to be present.
That some facts of geographical distribution supplement other difficulties.
That the objection drawn from the physiological difference between
"species" and "races" still exists unrefuted.
That there are many remarkable phenomena in organic forms upon which
"Natural Selection" throws no light whatever, but the explanations of
which, if they could be attained, might throw light upon specific
origination. [Page 22]
Besides these objections to the sufficiency of "Natural Selection," others
may be brought against the hypothesis of "Pangenesis," which, professing as
it does to explain great difficulties, seems to do so by presenting others
not less great--almost to be the explanation of _obscurum per {23}
obscurius_.
* * * * *
CHAPTER II.
THE INCOMPETENCY OF "NATURAL SELECTION" TO ACCOUNT FOR THE INCIPIENT STAGES
OF USEFUL STRUCTURES.
Mr. Darwin supposes that natural selection acts by slight
variations.--These must be useful at once.--Difficulties as to the
giraffe; as to mimicry; as to the heads of flat-fishes; as to the
origin and constancy of the vertebrate limbs; as to whalebone; as to
the young kangaroo; as to sea-urchins; as to certain processes of
metamorphosis; as to the mammary gland; as to certain ape characters;
as to the rattlesnake and cobra; as to the process of formation of the
eye and ear; as to the fully developed condition of the eye and ear; as
to the voice; as to shell-fish; as to orchids; as to ants.--The
necessity for the simultaneous modification of many
individuals.--Summary and conclusion.
"Natural Selection," simply and by itself, is potent to explain the
maintenance or the further extension and development of favourable
variations, which are at once sufficiently considerable to be useful from
the first to the individual possessing them. But Natural Selection utterly
fails to account for the conservation and development of the minute and
rudimentary beginnings, the slight and infinitesimal commencements of
structures, however useful those structures may afterwards become.
Now, it is distinctly enunciated by Mr. Darwin, that the spontaneous
variations upon which his theory depends are individually slight, minute,
and insensible. He says,[15] "Slight individual differences, however, {24}
suffice for the work, and are probably the sole differences which are
effective in the production of new species." And again, after mentioning
the frequent sudden appearances of domestic varieties, he speaks of "the
false belief as to the similarity of natural species in this respect."[16]
In his work on the "Origin of Species," he also observes, "Natural
Selection acts only by the preservation and accumulation of small inherited
modifications."[17] And "Natural Selection, if it be a true principle, will
banish the belief ... of any great and sudden modification in their
structure."[18] Finally, he adds, "If it could be demonstrated that any
complex organ existed, which could not possibly have been formed by
numerous, successive, slight modifications, my theory would absolutely
break down."[19]
Now the conservation of minute variations in many instances is, of course,
plain and intelligible enough; such, _e.g._, as those which tend to promote
the destructive faculties of beasts of prey on the one hand, or to
facilitate the flight or concealment of the animals pursued on the other;
provided always that these minute beginnings are of such a kind as really
to have a certain efficiency, however small, in favour of the conservation
of the individual possessing them; and also provided that no unfavourable
peculiarity in any other direction accompanies and neutralizes, in the
struggle for life, the minute favourable variation.
But some of the cases which have been brought forward, and which have met
with very general acceptance, seem less satisfactory when carefully
analysed than they at first appear to be. Amongst these we may mention "the
neck of the giraffe."
At first sight it would seem as though a better example in support of
"Natural Selection" could hardly have been chosen. Let the fact of the {25}
occurrence of occasional, severe droughts in the country which that animal
has inhabited be granted. In that case, when the ground vegetation has been
consumed, and the trees alone remain, it is plain that at such times only
those individuals (of what we assume to be the nascent giraffe species)
which were able to reach high up would be preserved, and would become the
parents of the following generation, some individuals of which would, of
course, inherit that high-reaching power which alone preserved their
parents. Only the high-reaching issue of these high-reaching individuals
would again, _cæteris paribus_, be preserved at the next drought, and would
again transmit to their offspring their still loftier stature; and so on,
from period to period, through æons of time, all the individuals tending to
revert to the ancient shorter type of body, being ruthlessly destroyed at
the occurrence of each drought.
(1.) But against this it may be said, in the first place, that the argument
proves too much; for, on this supposition, many species must have tended to
undergo a similar modification, and we ought to have at least several
forms, similar to the giraffe, developed from different Ungulata.[20] A
careful observer of animal life, who has long resided in South Africa,
explored the interior, and lived in the giraffe country, has assured the
Author that the giraffe has powers of locomotion and endurance fully equal
to those possessed by any of the other Ungulata of that continent. It would
seem, therefore, that some of these other Ungulates ought to have developed
in a similar manner as to the neck, under pain of being starved, when the
long neck of the giraffe was in its incipient stage.
To this criticism it has been objected that different kinds of animals are
preserved, in the struggle for life, in very different ways, and even {26}
that "high reaching" may be attained in more modes than one--as, for
example, by the trunk of the elephant. This is, indeed, true, but then none
of the African Ungulata[21] have, nor do they appear ever to have had, any
proboscis whatsoever; nor have they acquired such a development as to allow
them to rise on their hind limbs and graze on trees in a kangaroo-attitude,
nor a power of climbing, nor, as far as known, any other modification
tending to compensate for the comparative shortness of the neck. Again, it
may perhaps be said that leaf-eating forms are exceptional, and that
therefore the struggle to attain high branches would not affect many
Ungulates. But surely, when these severe droughts necessary for the theory
occur, the ground vegetation is supposed to be exhausted; and, indeed, the
giraffe is quite capable of feeding from off the ground. So that, in these
cases, the other Ungulata _must_ have taken to leaf eating or have starved,
and thus must have had any accidental long-necked varieties favoured and
preserved exactly as the long-necked varieties of the giraffe are supposed
to have been favoured and preserved.
The argument as to the different modes of preservation has been very well
put by Mr. Wallace,[22] in reply to the objection that "colour, being
dangerous, should not exist in nature." This objection appears similar to
mine; as I say that a giraffe neck, being needful, there should be many
animals with it, while the objector noticed by Mr. Wallace says, "a dull
colour being needful, all animals should be so coloured." And Mr. Wallace
shows in reply how porcupines, tortoises and mussels, very hard-coated
bombadier beetles, stinging insects and nauseous-tasted caterpillars, can
afford to be brilliant by the various means of active defence or passive
protection they possess, other than obscure colouration. He says "the {27}
attitudes of some insects may also protect them, as the habit of turning up
the tail by the harmless rove-beetles (Staphylinidæ) no doubt leads other
animals, besides children, to the belief that they can sting. The curious
attitude assumed by sphinx caterpillars is probably a safeguard, as well as
the blood-red tentacles which can suddenly be thrown out from the neck by
the caterpillars of all the true swallow-tailed butterflies."
But, because many different kinds of animals can elude the observation or
defy the attack of enemies in a great variety of ways, it by no means
follows that there are any similar number and variety of ways for attaining
vegetable food in a country where all such food, other than the lofty
branches of trees, has been for a time destroyed. In such a country we have
a number of vegetable-feeding Ungulates, all of which present minute
variations as to the length of the neck. If, as Mr. Darwin contends, the
natural selection of these favourable variations has alone lengthened the
neck of the giraffe by preserving it during droughts; similar variations,
in similarly-feeding forms, at the same times, ought similarly to have been
preserved and so lengthened the neck of some other Ungulates by similarly
preserving them during the same droughts.
(2.) It may be also objected, that the power of reaching upwards, acquired
by the lengthening of the neck and legs, must have necessitated a
considerable increase in the entire size and mass of the body (larger bones
requiring stronger and more voluminous muscles and tendons, and these again
necessitating larger nerves, more capacious blood-vessels, &c.), and it is
very problematical whether the disadvantages thence arising would not, in
times of scarcity, more than counterbalance the advantages.
For a considerable increase in the supply of food would be requisite on
account of this increase in size and mass, while at the same time there
would be a certain decrease in strength; for, as Mr. Herbert Spencer {28}
says,[23] "It is demonstrable that the excess of absorbed over expended
nutriment must, other things equal, become less as the size of an animal
becomes greater. In similarly-shaped bodies, the masses vary as the cubes
of the dimensions; whereas the strengths vary as the squares of the
dimensions.".... "Supposing a creature which a year ago was one foot high,
has now become two feet high, while it is unchanged in proportions and
structure--what are the necessary concomitant changes that have taken place
in it? It is eight times as heavy; that is to say, it has to resist eight
times the strain which gravitation puts on its structure; and in producing,
as well as in arresting, every one of its movements, it has to overcome
eight times the inertia. Meanwhile, the muscles and bones have severally
increased their contractile and resisting powers, in proportion to the
areas of their transverse sections; and hence are severally but four times
as strong as they were. Thus, while the creature has doubled in height, and
while its ability to overcome forces has quadrupled, the forces it has to
overcome have grown eight times as great. Hence, to raise its body through
a given space, its muscles have to be contracted with twice the intensity,
at a double cost of matter expended." Again, as to the cost at which
nutriment is distributed through the body, and effete matters removed from
it, "Each increment of growth being added at the periphery of an organism,
the force expended in the transfer of matter must increase in a rapid
progression--a progression more rapid than that of the mass."
There is yet another point. Vast as may have been the time during which the
process of evolution has continued, it is nevertheless not infinite. Yet,
as every kind, on the Darwinian hypothesis, varies slightly but
indefinitely in every organ and every part of every organ, how very
generally must favourable variations as to the length of the neck have {29}
been accompanied by some unfavourable variation in some other part,
neutralizing the action of the favourable one, the latter, moreover, only
taking effect during these periods of drought! How often must not
individuals, favoured by a slightly increased length of neck, have failed
to enjoy the elevated foliage which they had not strength or endurance to
attain; while other individuals, exceptionally robust, could struggle on
yet further till they arrived at vegetation within their reach.
However, allowing this example to pass, many other instances will be found
to present great difficulties.
Let us take the cases of mimicry amongst lepidoptera and other insects. Of
this subject Mr. Wallace has given a most interesting and complete
account,[24] showing in how many and strange instances this superficial
resemblance by one creature to some other quite distinct creature acts as a
safeguard to the first. One or two instances must here suffice. In South
America there is a family of butterflies, termed _Heliconidæ_, which are
very conspicuously coloured and slow in flight, and yet the individuals
abound in prodigious numbers, and take no precautions to conceal
themselves, even when at rest, during the night. Mr. Bates (the author of
the very interesting work "The Naturalist on the River Amazons," and the
discoverer of "Mimicry") found that these conspicuous butterflies had a
very strong and disagreeable odour; so much so that any one handling them
and squeezing them, as a collector must do, has his fingers stained and so
infected by the smell, as to require time and much trouble to remove it.
It is suggested that this unpleasant quality is the cause of the abundance
of the Heliconidæ; Mr. Bates and other observers reporting that they have
never seen them attacked by the birds, reptiles, or insects which prey upon
other lepidoptera.
Now it is a curious fact that very different South American butterflies{30}
put on, as it were, the exact dress of these offensive beauties and mimic
them even in their mode of flight.
In explaining the mode of action of this protecting resemblance Mr. Wallace
observes:[25] "Tropical insectivorous birds very frequently sit on dead
branches of a lofty tree, or on those which overhang forest paths, gazing
intently around, and darting off at intervals to seize an insect at a
considerable distance, with which they generally return to their station to
devour. If a bird began by capturing the slow-flying conspicuous
Heliconidæ, and found them always so disagreeable that it could not eat
them, it would after a very few trials leave off catching them at all; and
their whole appearance, form, colouring, and mode of flight is so peculiar,
that there can be little doubt birds would soon learn to distinguish them
at a long distance, and never waste any time in pursuit of them. Under
these circumstances, it is evident that any other butterfly of a group
which birds were accustomed to devour, would be almost equally well
protected by closely resembling a Heliconia externally, as if it acquired
also the disagreeable odour; always supposing that there were only a few of
them among a great number of Heliconias."
"The approach in colour and form to the Heliconidæ, however, would be at
the first a positive, though perhaps a slight, advantage; for although at
short distances this variety would be easily distinguished and devoured,
yet at a longer distance it might be mistaken for one of the uneatable
group, and so be passed by and gain another day's life, which might in many
cases be sufficient for it to lay a quantity of eggs and leave a numerous
progeny, many of which would inherit the peculiarity which had been the
safeguard of their parent."
[Illustration: LEAF BUTTERFLY IN FLIGHT AND REPOSE.
(_From Mr. Wallace's_ "_Malay Archipelago._")]
As a complete example of mimicry Mr. Wallace refers to a common Indian
butterfly. He says:[26] "But the most wonderful and undoubted case of
protective resemblance in a butterfly, which I have ever seen, is that {31}
of the common Indian _Kallima inachis_, and its Malayan ally, _Kallima
paralekta_. The upper surface of these is very striking and showy, as they
are of a large size, and are adorned with a broad band of rich orange {32}
on a deep bluish ground. The under side is very variable in colour, so that
out of fifty specimens no two can be found exactly alike, but every one of
them will be of some shade of ash, or brown, or ochre, such as are found
among dead, dry, or decaying leaves. The apex of the upper wings is
produced into an acute point, a very common form in the leaves of tropical
shrubs and trees, and the lower wings are also produced into a short narrow
tail. Between these two points runs a dark curved line exactly representing
the midrib of a leaf, and from this radiate on each side a few oblique
lines, which serve to indicate the lateral veins of a leaf. These marks are
more clearly seen on the outer portion of the base of the wings, and on the
inner side towards the middle and apex, and it is very curious to observe
how the usual marginal and transverse striæ of the group are here modified
and strengthened so as to become adapted for an imitation of the venation
of a leaf." ... "But this resemblance, close as it is, would be of little
use if the habits of the insect did not accord with it. If the butterfly
sat upon leaves or upon flowers, or opened its wings so as to expose the
upper surface, or exposed and moved its head and antennæ as many other
butterflies do, its disguise would be of little avail. We might be sure,
however, from the analogy of many other cases, that the habits of the
insect are such as still further to aid its deceptive garb; but we are not
obliged to make any such supposition, since I myself had the good fortune
to observe scores of _Kallima paralekta_, in Sumatra, and to capture many
of them, and can vouch for the accuracy of the following details. These
butterflies frequent dry forests, and fly very swiftly. They were seen to
settle on a flower or a green leaf, but were many times lost sight of in a
bush or tree of dead leaves. On such occasions they were generally searched
for in vain, for while gazing intently at the very spot where one had
disappeared, it would often suddenly dart out, and again vanish twenty or
fifty yards further on. On one or two occasions the insect was detected{33}
reposing, and it could then be seen how completely it assimilates itself to
the surrounding leaves. It sits on a nearly upright twig, the wings fitting
closely back to back, concealing the antennæ and head, which are drawn up
between their bases. The little tails of the hind wing touch the branch,
and form a perfect stalk to the leaf, which is supported in its place by
the claws of the middle pair of feet, which are slender and inconspicuous.
The irregular outline of the wings gives exactly the perspective effect of
a shrivelled leaf. We thus have size, colour, form, markings, and habits,
all combining together to produce a disguise which may be said to be
absolutely perfect; and the protection which it affords is sufficiently
indicated by the abundance of the individuals that possess it."
Beetles also imitate bees and wasps, as do some Lepidoptera; and objects
the most bizarre and unexpected are simulated, such as dung and drops of
dew. Some insects, called bamboo and walking-stick insects, have a most
remarkable resemblance to pieces of bamboo, to twigs and branches. Of these
latter insects Mr. Wallace says:[27] "Some of these are a foot long and as
thick as one's finger, and their whole colouring, form, rugosity, and the
arrangement of the head, legs, and antennæ, are such as to render them
absolutely identical in appearance with dry sticks. They hang loosely about
shrubs in the forest, and have the extraordinary habit of stretching out
their legs unsymmetrically, so as to render the deception more complete."
Now let us suppose that the ancestors of these various animals were all
destitute of the very special protections they at present possess, as on
the Darwinian hypothesis we must do. Let it also be conceded that small
deviations from the antecedent colouring or form would tend to make some of
their ancestors escape destruction by causing them more or less frequently
to be passed over, or mistaken by their persecutors. Yet the deviation {34}
must, as the event has shown, in each case be in some definite direction,
whether it be towards some other animal or plant, or towards some dead or
inorganic matter. But as, according to Mr. Darwin's theory, there is a
constant tendency to indefinite variation, and as the minute incipient
variations will be in _all directions_, they must tend to neutralize each
other, and at first to form such unstable modifications that it is
difficult, if not impossible, to see how such indefinite oscillations of
infinitesimal beginnings can ever build up a sufficiently appreciable
resemblance to a leaf, bamboo, or other object, for "Natural Selection" to
seize upon and perpetuate. This difficulty is augmented when we consider--a
point to be dwelt upon hereafter--how necessary it is that many individuals
should be similarly modified simultaneously. This has been insisted on in
an able article in the _North British Review_ for June 1867, p. 286, and
the consideration of the article has occasioned Mr. Darwin to make an
important modification in his views.[28]
In these cases of mimicry it seems difficult indeed to imagine a reason why
variations tending in an _infinitesimal degree_ in any special direction
should be preserved. All variations would be preserved which tended to
obscure the perception of an animal by its enemies, whatever direction
those variations might take, and the common preservation of conflicting
tendencies would greatly favour their mutual neutralization and
obliteration if we may rely on the many cases recently brought forward by
Mr. Darwin with regard to domestic animals.
[Illustration: THE WALKING-LEAF INSECT.]
Mr. Darwin explains the imitation of some species by others more or less
nearly allied to it, by the common origin of both the mimic and the
mimicked species, and the consequent possession by both (according to the
theory of "Pangenesis") of gemmules tending to reproduce ancestral
characters, which characters the mimic must be assumed first to have {35}
lost and then to have recovered. Mr. Darwin says,[29] "Varieties of one
species frequently mimic distinct species, a fact in perfect harmony with
the foregoing cases, and explicable _only on the theory of descent_." But
this at the best is but a partial and very incomplete explanation. It is
one, moreover, which Mr. Wallace does not accept.[30] It is very
incomplete, because it has no bearing on some of the most striking cases,
and of course Mr. Darwin does not pretend that it has. We should have to go
back far indeed to reach the common ancestor of the mimicking {36}
walking-leaf insect and the real leaf it mimics, or the original progenitor
of both the bamboo insect and the bamboo itself. As these last most
remarkable cases have certainly nothing to do with heredity,[31] it is
unwarrantable to make use of that explanation for other protective
resemblances, seeing that its inapplicability, in certain instances, is so
manifest.
Again, at the other end of the process it is as difficult to account for
the last touches of perfection in the mimicry. Some insects which imitate
leaves extend the imitation even to the very injuries on those leaves made
by the attacks of insects or of fungi. Thus, speaking of one of the
walking-stick insects, Mr. Wallace says:[32] "One of these creatures
obtained by myself in Borneo (_Ceroxylus laceratus_) was covered over with
foliaceous excrescences of a clear olive-green colour, so as exactly to
resemble a stick grown over by a creeping moss or jungermannia. The Dyak
who brought it me assured me it was grown over with moss although alive,
and it was only after a most minute examination that I could convince
myself it was not so." Again, as to the leaf butterfly, he says:[33] "We
come to a still more extraordinary part of the imitation, for we find
representations of leaves in every stage of decay, variously blotched, and
mildewed, and pierced with holes, and in many cases irregularly covered
with powdery black dots, gathered into patches and spots, so closely
resembling the various kinds of minute fungi that grow on dead leaves, that
it is impossible to avoid thinking at first sight that the butterflies
themselves have been attacked by real fungi."
Here imitation has attained a development which seems utterly beyond the
power of the mere "survival of the fittest" to produce. How this double
mimicry can importantly aid in the struggle for life seems puzzling indeed,
but much more so how the first faint beginnings of the imitation of {37}
such injuries in the leaf can be developed in the animal into such a
complete representation of them--_a fortiori_ how simultaneous and similar
first beginnings of imitations of such injuries could ever have been
developed in several individuals, out of utterly indifferent and
indeterminate infinitesimal variations in all conceivable directions.
[Illustration: PLEURONECTIDÆ, WITH THE PECULIARLY PLACED EYE IN DIFFERENT
POSITIONS.
(_From Dr. Traquair's paper in the "Transactions of the Linnean Society,
1865."_)]
Another instance which may be cited is the asymmetrical condition of the
heads of the flat-fishes (Pleuronectidæ), such as the sole, the flounder,
the brill, the turbot, &c. In all these fishes the two eyes, which in the
young are situated as usual one on each side, come to be placed, in the
adult, both on the same side of the head. If this condition had appeared at
once, if in the hypothetically fortunate common ancestor of these fishes an
eye had suddenly become thus transferred, then the perpetuation of such a
transformation by the action of "Natural Selection" is conceivable enough.
Such sudden changes, however, are not those favoured by the Darwinian
theory, and indeed the accidental occurrence of such a spontaneous
transformation is hardly conceivable. But if this is not so, if the transit
was gradual, then how such transit of one eye a minute fraction of the {38}
journey towards the other side of the head could benefit the individual is
indeed far from clear. It seems, even, that such an incipient
transformation must rather have been injurious. Another point with regard
to these flat-fishes is that they appear to be in all probability of recent
origin--_i.e._ geologically speaking. There is, of course, no great stress
to be laid on the mere absence of their remains from the secondary strata,
nevertheless that absence is noteworthy, seeing that existing fish
families, _e.g._ sharks (Squalidæ), have been found abundantly even down so
far as the carboniferous rocks, and traces of them in the Upper Silurian.
Another difficulty seems to be the first formation of the limbs of the
higher animals. The lowest Vertebrata[34] are perfectly limbless, and if,
as most Darwinians would probably assume, the primeval vertebrate creature
was also apodal, how are the preservation and development of the first
rudiments of limbs to be accounted for--such rudiments being, on the
hypothesis in question, infinitesimal and functionless?
In reply to this it has been suggested that a mere flattening of the end of
the body has been useful, such, _e.g._, as we see in sea-snakes,[35] which
may be the rudiment of a tail formed strictly to aid in swimming. Also that
a mere _roughness_ of the skin might be useful to a swimming animal by
holding the water better, that thus minute processes might be selected and
preserved, and that, in the same way, these might be gradually increased
into limbs. But it is, to say the least, very questionable whether a
roughness of the skin, or minute processes, would be useful to a {39}
swimming animal; the motion of which they would as much impede as aid,
unless they were at once capable of a suitable and appropriate action,
which is against the hypothesis. Again, the change from mere indefinite and
accidental processes to two regular pairs of symmetrical limbs, as the
result of merely fortuitous, favouring variations, is a step the
feasibility of which hardly commends itself to the reason, seeing the very
different positions assumed by the ventral fins in different fishes. If the
above suggestion made in opposition to the views here asserted be true,
then the general constancy of position of the limbs of vertebrata may be
considered as due to the position assumed by the primitive rugosities from
which those limbs were generated. Clearly only two pairs of rugosities were
so preserved and developed, and all limbs (on this view) are descendants of
the same two pairs, as all have so similar a fundamental structure. Yet we
find in many fishes the pair of fins, which correspond to the hinder limbs
of other animals, placed so far forwards as to be either on the same level
with, or actually in front of, the normally anterior pair of limbs; and
such fishes are from this circumstance called "thoracic," or "jugular"
fishes respectively, as the weaver fishes and the cod. This is a wonderful
contrast to the fixity of position of vertebrate limbs generally. If then
such a change can have taken place in the comparatively short time occupied
by the evolution of these special fish forms, we might certainly expect
other and far more bizarre structures would (did not some law forbid) have
been developed, from other rugosities, in the manifold exigencies of the
multitudinous organisms which must (on the Darwinian hypothesis) have been
gradually evolved during the enormous period intervening between the first
appearance of vertebrate life and the present day. Yet, with these
exceptions, the position of the limbs is constant from the lower fishes up
to man, there being always an anterior pectoral pair placed in front of a
posterior or pelvic pair when both are present, and in no single {40}
instance are there more than these two pairs.
[Illustration: MOUTH OF A WHALE.]
The development of whalebone (baleen) in the mouth of the whale is another
difficulty. A whale's mouth is furnished with very numerous horny plates,
which hang down from the palate along each side of the mouth. They thus
form two longitudinal series, each plate of which is placed transversely to
the long axis of the body, and all are very close together. On depressing
the lower lip the free outer edges of these plates come into view. Their
inner edges are furnished with numerous coarse hair-like processes,
consisting of some of the constituent fibres of the horny plates--which, as
it were, fray out--and the mouth is thus lined, except below, by a network
of countless fibres formed by the inner edges of the two series of plates.
This network acts as a sort of sieve. When the whale feeds it takes {41}
into its mouth a great gulp of water, which it drives out again through the
intervals of the horny plates of baleen, the fluid thus traversing the
sieve of horny fibres, which retains the minute creatures on which these
marine monsters subsist. Now it is obvious, that if this baleen had once
attained such a size and development as to be at all useful, then its
preservation and augmentation within serviceable limits, would be promoted
by "Natural Selection" alone. But how to obtain the beginning of such
useful development? There are indeed certain animals of exclusively aquatic
habits (the dugong and manatee) which also possess more or less horn on the
palate, and at first sight this might be taken as a mitigation of the
difficulty; but it is not so, and the fact does not help us one step
further along the road: for, in the first place, these latter animals
differ so importantly in structure from whales and porpoises that they form
an altogether distinct order, and cannot be thought to approximate to the
whale's progenitors. They are vegetarians, the whales feed on animals; the
former never have the ribs articulated in the mode in which they are in
some of the latter; the former have pectoral mammæ, and the latter are {42}
provided with two inguinal mammary glands, and have the nostrils enlarged
into blowers, which the former have not. The former thus constitute the
order Sirenia, while the latter belong to the Cetacea. In the second place,
the horny matter on the palates of the dugong and manatee has not, even
initially, that "strainer" action, which is the characteristic function of
the Cetacean "baleen."
[Illustration: FOUR PLATES OF BALEEN SEEN OBLIQUELY FROM WITHIN.]
[Illustration: DUGONG.]
There is another very curious structure, the origin or the disappearance of
which it seems impossible to account for on the hypothesis of minute
indefinite variations. It is that of the mouth of the young kangaroo. In
all mammals, as in ourselves, the air-passage from the lungs opens in the
floor of the mouth behind the tongue, and in front of the opening of the
gullet, so that each particle of food as it is swallowed passes over the
opening, but is prevented from falling into it (and thus causing death from
choking) by the action of a small cartilaginous shield (the epiglottis),
which at the right moment bends back and protects the orifice. Now the
kangaroo is born in such an exceedingly imperfect and undeveloped
condition, that it is quite unable to suck. The mother therefore places the
minute blind and naked young upon the nipple, and then injects milk into it
by means of a special muscular envelope of the mammary gland. Did no
special provision exist, the young one must infallibly be choked by the
intrusion of the milk into the windpipe. But there _is_ a special
provision. The larynx is so elongated that it rises up into the posterior
end of the nasal passage, and is thus enabled to give free entrance to the
air for the lungs, while the milk passes harmlessly on each side of this
elongated larynx, and so safely attains the gullet behind it.
Now, on the Darwinian hypothesis, either all mammals descended from
marsupial progenitors, or else the marsupials, sprung from animals having
in most respects the ordinary mammalian structure. [Page 43]
On the first alternative, how did "Natural Selection" remove this (at least
perfectly innocent and harmless) structure in almost all other mammals,
and, having done so, again reproduce it in precisely those forms which
alone require it, namely, the Cetacea? That such a harmless structure _need
not_ be removed any Darwinian must confess, since a structure exists in
both the crocodiles and gavials, which enables the former to breathe
themselves while drowning the prey which they hold in their mouths. On Mr.
Darwin's hypothesis it could only have been developed where useful,
therefore not in the gavials(!) which feed on fish, but which yet retain,
as we might expect, this, in them superfluous but harmless formation.
On the second alternative, how did the elongated larynx itself arise,
seeing that if its development lagged behind that of the maternal
structure, the young primeval kangaroo must be choked: while without the
injecting power in the mother, it must be starved? The struggle by the sole
action of which such a form was developed must indeed have been severe!
[Illustration: AN ECHINUS, OR SEA-URCHIN
(The spines removed from one-half.)]
The sea-urchins (Echinus) present us also with structures the origin of
which it seems impossible to explain by the action of "Natural {44}
Selection" only. These lowly animals belong to that group of the star-fish
class (Echinodermata), the species of which possess generally spheroidal
bodies, built up of multitudinous calcareous plates, and constitute the
order Echinoidea. They are also popularly known as sea-eggs. Utterly devoid
of limbs, the locomotion of these creatures is effected by means of rows of
small tubular suckers (which protrude through pores in the calcareous
plates) and by moveable spines scattered over the body.
[Illustration: PEDICELLARIÆ. (Immensely enlarged.)]
Besides these spines and suckers there are certain very peculiar
structures, termed "Pedicellariæ." Each of these consists of a long slender
stalk, ending in three short limbs--or rather jaws--the whole supported by
a delicate internal skeleton. The three limbs (or jaws), which start from a
common point at the end of the stalk, are in the constant habit of opening
and closing together again with a snapping action, while the stalk itself
sways about. The utility of these appendages is, even now, problematical.
It may be that they remove from the surface of the animal's body foreign
substances which would be prejudicial to it, and which it cannot otherwise
get rid of. But granting this, what would be the utility of the _first
rudimentary beginnings_ of such structures, and how could such incipient
buddings have ever preserved the life of a single Echinus? It is true that
on Darwinian principles the ancestral form from which the sea-urchin
developed was different, and must not be conceived merely as an Echinus
devoid of pedicellariæ; but this makes the difficulty none the less. It is
equally hard to imagine that the first rudiments of such structures could
have been useful to _any_ animal from which the Echinus might have been{45}
derived. Moreover, not even the _sudden_ development of the snapping action
could have been beneficial without the freely moveable stalk, nor could the
latter have been efficient without the snapping jaws, yet no minute merely
indefinite variations could simultaneously evolve these complex
co-ordinations of structure; to deny this seems to do no less than to
affirm a startling paradox.
Mr. Darwin explains the appearance of some structures, the utility of which
is not apparent, by the existence of certain "laws of correlation." By
these he means that certain parts or organs of the body are so related to
other organs or parts, that when the first are modified by the action of
"Natural Selection," or what not, the second are simultaneously affected,
and increase proportionally or possibly so decrease. Examples of such are
the hair and teeth in the naked Turkish dog, the general deafness of white
cats with blue eyes, the relation between the presence of more or less down
on young birds when first hatched, and the future colour of their
plumage,[36] with many others. But the idea that the modification of any
internal or external part of the body of an Echinus carries with it the
effect of producing elongated, flexible, triradiate, snapping processes,
is, to say the very least, fully as obscure and mysterious as what is here
contended for, viz. the efficient presence of an unknown internal natural
law or laws conditioning the evolution of new specific forms from preceding
ones, modified by the action of surrounding conditions, by "Natural
Selection" and by other controlling influences.
The same difficulty seems to present itself in other examples of
exceptional structure and action. In the same Echinus, as in many allied
forms, and also in some more or less remote ones, a very peculiar mode of
development exists. The adult is not formed from the egg directly, but {46}
the egg gives rise to a creature which swims freely about, feeds, and is
even somewhat complexly organized. Soon a small lump appears on one side of
its stomach; this enlarges, and, having established a communication with
the exterior, envelopes and appropriates the creature's stomach, with which
it swims away and develops into the complete adult form, while the
dispossessed individual perishes.
Again, certain flies present a mode of development equally bizarre, though
quite different. In these flies, the grub is, as usual, produced from the
ovum, but this grub, instead of growing up into the adult in the ordinary
way, undergoes a sort of liquefaction of a great part of its body, while
certain patches of formative tissue, which are attached to the ramifying
air tubes, or tracheæ (and which patches bear the name of "imaginal
disks"), give rise to the legs, wings, eyes, &c., respectively; and these
severally formed parts grow together, and build up the head and body by
their mutual approximation. Such a process is unknown outside the class of
insects, and inside that class it is only known in a few of the two-winged
flies. Now, how "Natural Selection," or any "laws of correlation," can
account for the gradual development of such an exceptional process of
development--so extremely divergent from that of other insects--seems
nothing less than inconceivable. Mr. Darwin himself[37] gives an account of
a very peculiar and abnormal mode of development of a certain beetle, the
sitaris, as described by M. Fabre. This insect, instead of at first
appearing in its grub stage, and then, after a time, putting on the adult
form, is at first active and furnished with six legs, two long antennæ, and
four eyes. Hatched in the nests of bees, it at first attaches itself to one
of the males, and then crawls, when the opportunity offers, upon a female
bee. When the female bee lays her eggs, the young sitaris springs upon them
and devours them. Then, losing its eyes, legs, and antennæ, and {47}
becoming rudimentary, it sinks into an ordinary grub-like form, and feeds
on honey, ultimately undergoing another transformation, re-acquiring its
legs, &c., and emerging a perfect beetle! That such a process should have
arisen by the accumulation of minute accidental variations in structure and
habit, appears to many minds, quite competent to form an opinion on the
subject, absolutely incredible.
It may be objected, perhaps, that these difficulties are _difficulties of
ignorance_--that we cannot explain them because we do not know _enough_ of
the animals. But it is here contended that this is not the case; it is not
that we merely fail to see how Natural Selection acted, but that there is a
positive incompatibility between the cause assigned and the results. It
will be stated shortly what wonderful instances of co-ordination and of
unexpected utility Mr. Darwin has discovered in orchids. The discoveries
are not disputed or undervalued, but the explanation of their _origin_ is
deemed thoroughly unsatisfactory--utterly insufficient to explain the
incipient, infinitesimal beginnings of structures which are of utility only
when they are considerably developed.
Let us consider the mammary gland, or breast. Is it conceivable that the
young of any animal was ever saved from destruction by accidentally sucking
a drop of scarcely nutritious fluid from an accidentally hypertrophied
cutaneous gland of its mother? And even if one was so, what chance was
there of the perpetuation of such a variation? On the hypothesis of Natural
Selection itself, we must assume that up to that time the race had been
well adapted to the surrounding conditions; the temporary and accidental
trial and change of conditions, which caused the so-sucking young one to be
the "fittest to survive" under the supposed circumstances, would soon cease
to act, and then the progeny of the mother, with the accidentally
hypertrophied, sebaceous glands, would have no tendency to survive the {48}
far outnumbering descendants of the normal ancestral form. If, on the other
hand, we assume the change of conditions not to have been temporary but
permanent, and also assume that this permanent change of conditions was
accidentally synchronous with the change of structure, we have a
coincidence of very remote probability indeed. But if, again, we accept the
presence of some harmonizing law simultaneously determining the two
changes, or connecting the second with the first by causation, then, of
course, we remove the accidental character of the coincidence.
Again, how explain the external position of the male sexual glands in
certain mammals? The utility of the modification, when accomplished, is
problematical enough, and no less so the incipient stages of the descent.
As was said in the first chapter, Mr. Darwin explains the brilliant plumage
of the peacock or the humming-bird by the action of sexual selection: the
more and more brilliant males being selected by the females (which are thus
attracted) to become the fathers of the next generation, to which
generation they tend to communicate their own bright nuptial vesture. But
there are peculiarities of colour and of form which it is exceedingly
difficult to account for by any such action. Thus, amongst apes, the female
is notoriously weaker, and is armed with much less powerful canine tusks
than the male. When we consider what is known of the emotional nature of
these animals, and the periodicity of its intensification, it is hardly
credible that a female would often risk life or limb through her admiration
of a trifling shade of colour, or an infinitesimally greater though
irresistibly fascinating degree of wartiness.[38]
{49}
[Illustration: RATTLESNAKE.]
Yet the males of some kinds of ape are adorned with quite exceptionally
brilliant local decoration, and the male orang is provided with remarkable,
projecting, warty lumps of skin upon the cheeks. As we have said, the
weaker female can hardly be supposed to have developed these by persevering
and long-continued selection, nor can they be thought to tend to the
preservation of the individual. On the contrary, the presence of this
enlarged appendage must occasion a slight increase in the need of
nutriment, and in so far must be a detriment, although its detrimental
effect would not be worth speaking of except in relation to "Darwinism,"
according to which, "selection" has acted through unimaginable ages, {50}
and has ever tended to suppress any useless development by the struggle for
life.[39]
[Illustration: COBRA.
(_Copied, by permission, from Sir Andrew Smith's "Reptiles of South
Africa."_)]
In poisonous serpents, also, we have structures which, at all events at
first sight, seem positively hurtful to those reptiles. Such are the rattle
of the rattlesnake, and the expanding neck of the cobra, the former seeming
to warn the ear of the intended victim, as the latter warns the eye. It is
true we cannot perhaps demonstrate that the victims are alarmed and warned,
but, on Darwinian principles, they certainly ought to be so. For the {51}
rashest and most incautious of the animals preyed on would always tend to
fall victims, and the existing individuals being the long-descended progeny
of the timid and cautious, ought to have an inherited tendency to distrust,
amongst other things, both "rattling" and "expanding" snakes. As to any
power of fascination exercised by means of these actions, the most
distinguished naturalists, certainly the most distinguished erpetologists,
entirely deny it, and it is opposed to the careful observations of those
known to us.[40]
The mode of formation of both the eye and the ear of the highest animals is
such that, if it is (as most Darwinians assert processes of development to
be) a record of the actual steps by which such structures were first
evolved in antecedent forms, it almost amounts to a demonstration that
those steps were never produced by "Natural Selection."
The eye is formed by a simultaneous and corresponding ingrowth of one part
and outgrowth of another. The skin in front of the future eye becomes
depressed, the depression increases and assumes the form of a sac, which
changes into the aqueous humour and lens. An outgrowth of brain substance,
on the other hand, forms the retina, while a third process is a lateral
ingrowth of connective tissue, which afterwards changes into the vitreous
humour of the eye.
The internal ear is formed by an involution of the integument, and not by
an outgrowth of the brain. But tissue, in connexion with it, becomes in
part changed, thus forming the auditory nerve, which places the tegumentary
sac in direct communication with the brain itself.
{52}
Now, these complex and simultaneous co-ordinations could never have been
produced by infinitesimal beginnings, since, until so far developed as to
effect the requisite junctions, they are useless. But the eye and ear when
fully developed present conditions which are hopelessly difficult to
reconcile with the mere action of "Natural Selection." The difficulties
with regard to the eye have been well put by Mr. Murphy, especially that of
the concordant result of visual development springing from different
starting-points and continued on by independent roads.
He says,[41] speaking of the beautiful structure of the perfect eye, "The
higher the organization, whether of an entire organism or of a single
organ, the greater is the number of the parts that co-operate, and the more
perfect is their co-operation; and consequently, the more necessity there
is for corresponding variations to take place in all the co-operating parts
at once, and the more useless will be any variation whatever unless it is
accompanied by corresponding variations in the co-operating parts; while it
is obvious that the greater the number of variations which are needed in
order to effect an improvement, the less will be the probability of their
all occurring at once. It is no reply to this to say, what is no doubt
abstractedly true, that whatever is possible becomes probable, if only time
enough be allowed. There are improbabilities so great that the common sense
of mankind treats them as impossibilities. It is not, for instance, in the
strictest sense of the word, impossible that a poem and a mathematical
proposition should be obtained by the process of shaking letters out of a
box; but it is improbable to a degree that cannot be distinguished from
impossibility; and the improbability of obtaining an improvement in an
organ by means of several spontaneous variations, all occurring together,
is an improbability of the same kind. If we suppose that any single
variation occurs on the average once in _m_ times, the probability of {53}
that variation occurring in any individual will be
1/_m_;
and suppose that _x_ variations must concur in order to make an
improvement, then the probability of the necessary variations all occurring
together will be
1/_m_^x.
Now suppose, what I think a moderate proposition, that the value of _m_ is
1,000, and the value of _x_ is 10, then
1/_m_^x = 1/1000^{10} = 1/10^{30}.
A number about ten thousand times as great as the number of waves of light
that have fallen on the earth since historical time began. And it is to be
further observed, that no improvement will give its possessor a _certainty_
of surviving and leaving offspring, but only an _extra chance_, the value
of which it is quite impossible to estimate." This difficulty is, as Mr.
Murphy points out, greatly intensified by the undoubted fact that the
wonderfully complex structure has been arrived at quite independently in
beasts on the one hand and in cuttle-fishes on the other; while creatures
of the insect and crab division present us with a third and quite
separately developed complexity.
As to the ear, it would take up too much space to describe its internal
structure;[42] it must suffice to say that in its interior there is an
immense series of minute rod-like bodies, termed _fibres of Corti_, having
the appearance of a key-board, and each fibre being connected with a
filament of the auditory nerve, these nerves being like strings to be
struck by the keys, _i.e._ by the fibres of Corti. Moreover, this apparatus
is supposed to be a key-board in function as well as in appearance, the{54}
vibration of each one fibre giving rise, it is believed, to the sensation
of one particular tone, and combinations of such vibrations producing
chords. It is by the action of this complex organ then, that all the
wonderful intricacy and beauty of Beethoven and Mozart come, most probably,
to be perceived and appreciated.
Now it can hardly be contended that the preservation of any race of men in
the struggle for life ever depended on such an extreme delicacy and
refinement of the internal ear,--a perfection only exercised in the
enjoyment and appreciation of the most perfect musical performances. How,
then, could either the minute incipient stages, or the final perfecting
touches of this admirable structure, have been brought about by vague,
aimless, and indefinite variations in all conceivable directions of an
organ, suitable to enable the rudest savage to minister to his necessities,
but no more?
Mr. Wallace[43] makes an analogous remark with regard to the organ of voice
in man--the human larynx. He says of singing: "The habits of savages give
no indication of how this faculty could have been developed by Natural
Selection, because it is never required or used by them. The singing of
savages is a more or less monotonous howling, and the females seldom sing
at all. Savages certainly never choose their wives for fine voices, but for
rude health, and strength, and physical beauty. Sexual selection could not
therefore have developed this wonderful power, which only comes into play
among civilized people."
Reverting once more to beauty of form and colour, there is one
manifestation of it for which no one can pretend that sexual selection can
possibly account. The instance referred to is that presented by bivalve
shell-fish.[44] Here we meet with charming tints and elegant forms and
markings of no direct use to their possessors[45] in the struggle for {55}
life, and of no indirect utility as regards sexual selection, for
fertilization takes place by the mere action of currents of water, and the
least beautiful individual has fully as good a chance of becoming a parent
as has the one which is the most favoured in beauty of form and colour.
Again, the peculiar outline and coloration of certain orchids--notably of
our own bee, fly, and spider orchids--seem hardly explicable by any action
of "Natural Selection." Mr. Darwin says very little on this singular
resemblance of flowers to insects, and what he does say seems hardly to be
what an advocate of "Natural Selection" would require. Surely, for minute
accidental indefinite variations to have built up such a striking
resemblance to insects, we ought to find that the preservation of the
plant, or the perpetuation of its race, depends almost constantly on
relations between bees, spiders, and flies respectively and the bee,
spider, and fly orchids.[46] This process must have continued for ages
constantly and perseveringly, and yet what is the fact? Mr. Darwin tells
us, in his work on the Fertilization of Orchids, that neither the spider
nor the fly orchids are much visited by insects, while, with regard to the
bee orchid, he says, "I have never seen an insect visit these flowers." And
he shows how this species is even wonderfully and specially modified to
effect self-fertilization.
In the work just referred to Mr. Darwin gives a series of the most
wonderful and minute contrivances by which the visits of insects are
utilized for the fertilization of orchids,--structures so wonderful {56}
that nothing could well be more so, except the attribution of their origin
to minute, fortuitous, and indefinite variation.
The instances are too numerous and too long to quote, but in his "Origin of
Species"[47] he describes two which must not be passed over. In one
(_Coryanthes_) the orchid has its lower lip enlarged into a bucket, above
which stand two water-secreting horns. These latter replenish the bucket
from which, when half-filled, the water overflows by a spout on one side.
Bees visiting the flower fall into the bucket and crawl out at the spout.
By the peculiar arrangement of the parts of the flower, the first bee which
does so carries away the pollen-mass glued to his back, and then when he
has his next involuntary bath in another flower, as he crawls out the
pollen-mass attached to him comes in contact with the stigma of that second
flower and fertilizes it. In the other example (_Catasetum_), when a bee
gnaws a certain part of the flower, he inevitably touches a long delicate
projection, which Mr. Darwin calls the antenna. "This antenna transmits a
vibration to a certain membrane, which is instantly ruptured; this sets
free a spring by which the pollen-mass is shot forth like an arrow in the
right direction, and adheres by its viscid extremity to the back of the
bee!"
Another difficulty, and one of some importance, is presented by those
communities of ants which have not only a population of sterile females, or
workers, but two distinct and very different castes of such. Mr. Darwin
believes that he has got over this difficulty by having found individuals
intermediate in form and structure[48] between the two working castes;
others may think that we have in this belief of Mr. Darwin, an example {57}
of the unconscious action of volition upon credence. A vast number of
difficulties similar to those which have been mentioned might easily be
cited--those given, however, may suffice.
There remains, however, to be noticed a very important consideration, which
was brought forward in the _North British Review_ for June 1867, p. 286,
namely, the necessity for the simultaneous modification of _many
individuals_. This consideration seems to have escaped Mr. Darwin, for at
p. 104 of his last (fifth) edition of "Natural Selection," he admits, with
great candour, that until reading this article he did not "appreciate how
rarely single variations, whether slight or strongly marked, could be
perpetuated."
The _North British Review_ (speaking of the supposition that a species is
changed by the survival of a few individuals in a century through a similar
and favourable variation) says: "It is very difficult to see how this can
be accomplished, even when the variation is eminently favourable indeed;
and still more difficult when the advantage gained is very slight, as must
generally be the case. The advantage, whatever it may be, is utterly
outbalanced by numerical inferiority. A million creatures are born; ten
thousand survive to produce offspring. One of the million has twice as good
a chance as any other of surviving; but the chances are fifty to one
against the gifted individuals being one of the hundred survivors. No doubt
the chances are twice as great against any one other individual, but this
does not prevent their being enormously in favour of _some_ average
individual. However slight the advantage may be, if it is shared by half
the individuals produced, it will probably be present in at least fifty-one
of the survivors, and in a larger proportion of their offspring; but the
chances are against the preservation of any one 'sport' (_i.e._ sudden,
marked variation) in a numerous tribe. The vague use of an imperfectly
understood doctrine of chance has led Darwinian supporters, first, to
confuse the two cases above distinguished; and, secondly, to imagine {58}
that a very slight balance in favour of some individual sport must lead to
its perpetuation. All that can be said is that in the above example the
favoured sport would be preserved once in fifty times. Let us consider what
will be its influence on the main stock when preserved. It will breed and
have a progeny of say 100; now this progeny will, on the whole, be
intermediate between the average individual and the sport. The odds in
favour of one of this generation of the new breed will be, say one and a
half to one, as compared with the average individual; the odds in their
favour will, therefore, be less than that of their parents; but owing to
their greater number, the chances are that about one and a half of them
would survive. Unless these breed together, a most improbable event, their
progeny would again approach the average individual; there would be 150 of
them, and their superiority would be, say in the ratio of one and a quarter
to one; the probability would now be that nearly two of them would survive,
and have 200 children, with an eighth superiority. Rather more than two of
these would survive; but the superiority would again dwindle, until after a
few generations it would no longer be observed, and would count for no more
in the struggle for life than any of the hundred trifling advantages which
occur in the ordinary organs. An illustration will bring this conception
home. Suppose a white man to have been wrecked on an island inhabited by
negroes, and to have established himself in friendly relations with a
powerful tribe, whose customs he has learnt. Suppose him to possess the
physical strength, energy, and ability of a dominant white race, and let
the food and climate of the island suit his constitution; grant him every
advantage which we can conceive a white to possess over the native; concede
that in the struggle for existence his chance of a long life will be much
superior to that of the native chiefs; yet from all these admissions, there
does not follow the conclusion that, after a limited or unlimited {59}
number of generations, the inhabitants of the island will be white. Our
shipwrecked hero would probably become king; he would kill a great many
blacks in the struggle for existence; he would have a great many wives and
children." ... "In the first generation there will be some dozens of
intelligent young mulattoes, much superior in average intelligence to the
negroes. We might expect the throne for some generations to be occupied by
a more or less yellow king; but can any one believe that the whole island
will gradually acquire a white, or even a yellow, population?"
"Darwin says that in the struggle for life a grain may turn the balance in
favour of a given structure, which will then be preserved. But one of the
weights in the scale of nature is due to the number of a given tribe. Let
there be 7000 A's and 7000 B's, representing two varieties of a given
animal, and let all the B's, in virtue of a slight difference of structure,
have the better chance of life by 1/7000 part. We must allow that there is
a slight probability that the descendants of B will supplant the
descendants of A; but let there be only 7001 A's against 7000 B's at first,
and the chances are once more equal, while if there be 7002 A's to start,
the odds would be laid on the A's. True, they stand a greater chance of
being killed; but then they can better afford to be killed. The grain will
only turn the scales when these are very nicely balanced, and an advantage
in numbers counts for weight, even as an advantage in structure. As the
numbers of the favoured variety diminish, so must its relative advantages
increase, if the chance of its existence is to surpass the chance of its
extinction, until hardly any conceivable advantage would enable the
descendants of a single pair to exterminate the descendants of many
thousands if they and their descendants are supposed to breed freely with
the inferior variety, and so gradually lose their ascendency."
Mr. Darwin himself says of the article quoted: "The justice of these
remarks cannot, I think, be disputed. If, for instance, a bird of some {60}
kind could procure its food more easily by having its beak curved, and if
one were born with its beak strongly curved, and which consequently
flourished, nevertheless there would be a very poor chance of this one
individual perpetuating its kind to the exclusion of the common form." This
admission seems almost to amount to a change of front in the face of the
enemy!
These remarks have been quoted at length because they so greatly intensify
the difficulties brought forward in this chapter. If the most favourable
variations have to contend with such difficulties, what must be thought as
to the chance of preservation of the slightly displaced eye in a sole or of
the incipient development of baleen in a whale?
SUMMARY AND CONCLUSION.
It has been here contended that a certain few facts, out of many which
might have been brought forward, are inconsistent with the origination of
species by "Natural Selection" only or mainly.
Mr. Darwin's theory requires minute, indefinite, fortuitous variations of
all parts in all directions, and he insists that the sole operation of
"Natural Selection" upon such is sufficient to account for the great
majority of organic forms, with their most complicated structures,
intricate mutual adaptations and delicate adjustments.
To this conception has been opposed the difficulties presented by such a
structure as the form of the giraffe, which ought not to have been the
solitary structure it is; also the minute beginnings and the last
refinements of protective mimicry equally difficult or rather impossible to
account for by "Natural Selection." Again the difficulty as to the heads of
flat-fishes has been insisted on, as also the origin, and at the same time
the constancy, of the limbs of the highest animals. Reference has also been
made to the whalebone of whales, and to the impossibility of {61}
understanding its origin through "Natural Selection" only; the same as
regards the infant kangaroo, with its singular deficiency of power
compensated for by maternal structures on the one hand, to which its own
breathing organs bear direct relation on the other. Again, the delicate and
complex pedicellariæ of Echinoderms, with a certain process of development
(through a secondary larva) found in that class, together with certain
other exceptional modes of development, have been brought forward. The
development of colour in certain apes, the hood of the cobra, and the
rattle of the rattlesnake have also been cited. Again, difficulties as to
the process of formation of the eye and ear, and as to the fully developed
condition of those complex organs, as well as of the voice, have been
considered. The beauty of certain shell-fish; the wonderful adaptations of
structure, and variety of form and resemblance, found in orchids; together
with the complex habits and social conditions of certain ants, have been
hastily passed in review. When all these complications are duly weighed and
considered, and when it is borne in mind how necessary it is for the
permanence of a new variety that many individuals in each case should be
simultaneously modified, the cumulative argument seems irresistible.
The Author of this book can say that though by no means disposed originally
to dissent from the theory of "Natural Selection," if only its difficulties
could be solved, he has found each successive year that deeper
consideration and more careful examination have more and more brought home
to him the inadequacy of Mr. Darwin's theory to account for the
preservation and intensification of incipient, specific, and generic
characters. That minute, fortuitous, and indefinite variations could have
brought about such special forms and modifications as have been enumerated
in this chapter, seems to contradict not imagination, but reason. [Page 62]
That either many individuals amongst a species of butterfly should be
simultaneously preserved through a similar accidental and minute variation
in one definite direction, when variations in many other directions would
also preserve; or that one or two so varying should succeed in supplanting
the progeny of thousands of other individuals, and that this should by no
other cause be carried so far as to produce the appearance (as we have
before stated) of spots of fungi, &c.--are alternatives of an improbability
so extreme as to be practically equal to impossibility.
In spite of all the resources of a fertile imagination, the Darwinian, pure
and simple, is reduced to the assertion of a paradox as great as any he
opposes. In the place of a mere assertion of our ignorance as to the way
these phenomena have been produced, he brings forward, as their
explanation, a cause which it is contended in this work is demonstrably
insufficient.
Of course in this matter, as elsewhere throughout nature, we have to do
with the operation of fixed and constant natural laws, and the knowledge of
these may before long be obtained by human patience or human genius; but
there is, it is believed, already enough evidence to show that these as yet
unknown natural laws or law will never be resolved into the action of
"Natural Selection," but will constitute or exemplify a mode and condition
of organic action of which the Darwinian theory takes no account
whatsoever. [Page 63]
* * * * *
CHAPTER III.
THE CO-EXISTENCE OF CLOSELY SIMILAR STRUCTURES OF DIVERSE ORIGIN.
Chances against concordant variations.--Examples of discordant
ones.--Concordant variations not unlikely on a non-Darwinian
evolutionary hypothesis.--Placental and implacental mammals.--Birds and
reptiles.--Independent origins of similar sense organs.--The ear.--The
eye.--Other coincidences.--Causes besides Natural Selection produce
concordant variations in certain geographical regions.--Causes besides
Natural Selection produce concordant variations in certain zoological
and botanical groups.--There are homologous parts not genetically
related.--Harmony in respect of the organic and inorganic
worlds.--Summary and conclusion.
The theory of "Natural Selection" supposes that the varied forms and
structure of animals and plants have been built up merely by indefinite,
fortuitous,[49] minute variations in every part and in all
directions--those variations only being preserved which are directly or
indirectly useful to the individual possessing them, or necessarily
correlated with such useful variations.
[Illustration: WINGBONES OF PTERODACTYLE, BAT, AND BIRD.
(_Copied, by permission, from Mr. Andrew Murray's "Geographical
Distribution of Mammals."_)]
On this theory the chances are almost infinitely great against the
independent, accidental occurrence and preservation of two similar series
of minute variations resulting in the independent development of two
closely similar forms. In all cases, no doubt (on this same theory), _some_
adaptation to habit or need would gradually be evolved, but that {64}
adaptation would surely be arrived at by different roads. The organic world
supplies us with multitudes of examples of similar functional results being
attained by the most diverse means. Thus the body is sustained in the air
by birds and by bats. In the first case it is so sustained by a limb in
which the bones of the hand are excessively reduced, but which is provided
with immense outgrowths from the skin--namely, the feathers of the wing. In
the second case, however, the body is sustained in the air by a limb in
which the bones of the hand are enormously increased in length, and so
sustain a great expanse of naked skin, which is the flying membrane of the
bat's wing. Certain fishes and certain reptiles can also flit and take very
prolonged jumps in the air. The flying-fish, however, takes these by means
of a great elongation of the rays of the pectoral fins--parts which cannot
be said to be of the same nature as the constituents of the wing of either
the bat or the bird. The little lizard, which enjoys the formidable name of
"flying-dragon," flits by means of a structure altogether peculiar--namely,
by the liberation and great elongation of some of the ribs which support a
fold of skin. In the extinct pterodactyles--which were _truly_ flying {65}
reptiles--we meet with an approximation to the structure of the bat, but in
the pterodactyle we have only one finger elongated in each hand: a striking
example of how the very same function may be provided for by a modification
similar in principle, yet surely manifesting the independence of its
origin. When we go to lower animals, we find flight produced by organs, as
the wings of insects, which are not even modified limbs at all; or we find
even the function sometimes subserved by quite artificial means, as in the
aërial spiders, which use their own threads to float with in the air. In
the vegetable kingdom the atmosphere is often made use of for the
scattering of seeds, by their being furnished with special structures of
very different kinds. The diverse modes by which such seeds are dispersed
are well expressed by Mr. Darwin. He says:[50] "Seeds are disseminated {66}
by their minuteness,--by their capsule being converted into a light
balloon-like envelope,--by being embedded in pulp or flesh, formed of the
most diverse parts, and rendered nutritious, as well as conspicuously
coloured, so as to attract and be devoured by birds,--by having hooks and
grapnels of many kinds and serrated awns, so as to adhere to the fur of
quadrupeds,--and by being furnished with wings and plumes, as different in
shape as elegant in structure, so as to be wafted by every breeze."
[Illustration: SKELETON OF THE FLYING-DRAGON.
(Showing the elongated ribs which support the flitting organ.)]
Again, if we consider the poisoning apparatus possessed by different
animals, we find in serpents a perforated--or rather very deeply
channelled--tooth. In wasps and bees the sting is formed of modified parts,
accessory in reproduction. In the scorpion, we have the median terminal
process of the body specially organized. In the spider, we have a specially
constructed antenna; and finally in the centipede a pair of modified
thoracic limbs.
[Illustration: A CENTIPEDE.]
It would be easy to produce a multitude of such instances of similar ends
being attained by dissimilar means, and it is here contended that by "the
action of Natural Selection" _only_ it is so improbable as to be
practically impossible for two exactly similar structures to have ever been
independently developed. It is so because the number of possible {67}
variations is indefinitely great, and it is therefore an indefinitely great
number to one against a similar series of variations occurring and being
similarly preserved in any two independent instances.
The difficulty here asserted applies, however, only to pure Darwinism,
which makes use _only_ of indirect modifications through the survival of
the fittest.
Other theories (for example, that of Mr. Herbert Spencer) admit the
_direct_ action of conditions upon animals and plants--in ways not yet
fully understood--there being conceived to be at the same time a certain
peculiar but limited power of response and adaptation in each animal and
plant so acted on. Such theories have not to contend against the difficulty
proposed, and it is here urged that even very complex extremely similar
structures have again and again been developed quite independently one of
the other, and this because the process has taken place not by merely
haphazard, indefinite variations in all directions, but by the concurrence
of some other and internal natural law or laws co-operating with external
influences and with Natural Selection in the evolution of organic forms.
It must never be forgotten that to admit any such constant operation of any
such unknown natural cause is to deny the purely Darwinian theory, which
relies upon the survival of the fittest by means of minute fortuitous
indefinite variations.
Amongst many other obligations which the Author has to acknowledge to
Professor Huxley, are the pointing out of this very difficulty, and the
calling his attention to the striking resemblance between certain teeth of
the dog and of the thylacine as one instance, and certain ornithic
peculiarities of pterodactyles as another.
Mammals[51] are divisible into one great group, which comprises the {68}
immense majority of kinds termed, from their mode of reproduction,
_placental Mammals_, and into another very much smaller group comprising
the pouched-beasts or marsupials (which are the kangaroos, bandicoots,
phalangers, &c., of Australia), and the true opossums of America, called
_implacental Mammals_. Now the placental mammals are subdivided into
various orders, amongst which are the flesh-eaters (Carnivora, _i.e._ cats,
dogs, otters, weasels, &c.), and the insect-eaters (Insectivora, _i.e._
moles, hedgehogs, shrew-mice, &c.). The marsupial mammals also present a
variety of forms (some of which are carnivorous beasts, whilst others are
insectivorous), so marked that it has been even proposed to divide them
into orders parallel to the orders of placental beasts.
The resemblance, indeed, is so striking as, on Darwinian principles, to
suggest the probability of genetic affinity; and it even led Professor
Huxley, in his Hunterian Lectures, in 1866, to promulgate the notion that a
vast and widely-diffused marsupial fauna may have existed anteriorly to the
development of the ordinary placental, non-pouched beasts, and that the
carnivorous, insectivorous, and herbivorous placentals may have
respectively descended from the carnivorous, insectivorous, and herbivorous
marsupials.
[Illustration: TEETH OF UROTRICHUS AND PERAMELES.]
Amongst other points Professor Huxley called attention to the resemblance
between the anterior molars of the placental dog with those of the
marsupial thylacine. These, indeed, are strikingly similar, but there are
better examples still of this sort of coincidence. Thus it has often {69}
been remarked that the insectivorous marsupials, _e.g. Perameles_,
wonderfully correspond, as to the form of certain of the grinding teeth,
with certain insectivorous placentals, _e.g. Urotrichus_.
Again, the saltatory insectivores of Africa (_Macroscelides_) not only
resemble the kangaroo family (_Macropodidæ_) in their jumping habits and
long hind legs, but also in the structure of their molar teeth, and even
further, as I have elsewhere[52] pointed out, in a certain similarity of
the upper cutting teeth, or incisors.
Now these correspondences are the more striking when we bear in mind that a
similar dentition is often put to very different uses. The food of
different kinds of apes is very different, yet how uniform is their dental
structure! Again, who, looking at the teeth of different kinds of bears,
would ever suspect that one kind was frugivorous, and another a devourer
exclusively of animal food?
The suggestion made by Professor Huxley was therefore one which had much to
recommend it to Darwinians, though it has not met with any notable
acceptance, and though he seems himself to have returned to the older
notion, namely, that the pouched-beasts, or marsupials, are a special
ancient offshoot from the great mammalian class.
But whichever view may be the correct one, we have in either case a number
of forms similarly modified in harmony with surrounding conditions, and
eloquently proclaiming some natural plastic power, other than mere
fortuitous variation with survival of the fittest. If, however, the Reader
thinks that teeth are parts peculiarly qualified for rapid variation (in
which view the Author cannot concur), he is requested to suspend his
judgment till he has considered the question of the independent evolution
of the _highest organs of sense_. If this seems to establish the {70}
existence of some other law than that of "Natural Selection," then the
operation of that other law may surely be also traced in the harmonious
co-ordinations of dental form.
The other difficulty, kindly suggested to me by the learned Professor,
refers to the structure of birds, and of extinct reptiles more or less
related to them.
The class of birds is one which is remarkably uniform in its organization.
So much is this the case, that the best mode of subdividing the class is a
problem of the greatest difficulty. Existing birds, however, present forms
which, though closely resembling in the greater part of their structure,
yet differ importantly the one from the other. One form is exemplified by
the ostrich, rhea, emeu, cassowary, apteryx, dinornis, &c. These are the
_struthious_ birds. All other existing birds belong to the second division,
and are called (from the keel on the breast-bone) _carinate_ birds.
Now birds and reptiles have such and so many points in common, that
Darwinians must regard the former as modified descendants of ancient
reptilian forms. But on Darwinian principles it is impossible that the
class of birds so uniform and homogeneous should have had a double
reptilian origin. If one set of birds sprang from one set of reptiles, and
another set of birds from another set of reptiles, the two sets could
never, by "Natural Selection" only, have grown into such a perfect
similarity. To admit such a phenomenon would be equivalent to abandoning
the theory of "Natural Selection" as the sole origin of species.
Now, until recently it has generally been supposed by evolutionists that
those ancient flying reptiles, the pterodactyles, or forms allied to them,
were the progenitors of the class of birds; and certain parts of their
structure especially support this view. Allusion is here made to the
bladebone (scapula), and the bone which passes down from the shoulder-joint
to the breast-bone (viz. the coracoid). These bones are such remarkable
anticipations of the same parts in ordinary (_i.e._ carinate) birds {71}
that it is hardly possible for a Darwinian not to regard the resemblance as
due to community of origin. This resemblance was carefully pointed out by
Professor Huxley in his "Hunterian Course" for 1867, when attention was
called to the existence in _Dimorphodon macronyx_ of even that small
process which in birds gives attachment to the upper end of the
merrythought. Also Mr. Seeley[53] has shown that in pterodactyles, as in
birds, the optic lobes of the brain were placed low down on each
side--"lateral and depressed." Nevertheless, the view has been put forward
and ably maintained by the same Professor,[54] as also by Professor Cope in
the United States, that the line of descent from reptiles to birds has not
been from ordinary reptiles, through pterodactyle-like forms, to ordinary
birds, but to the struthious ones from certain extinct reptiles termed
Dinosauria; one of the most familiarly known of which is the Iguanodon of
the Wealden formation. In these Dinosauria we find skeletal characters
unlike those of ordinary (_i.e._ carinate) birds, but closely resembling in
certain points the osseous structure of the struthious birds. Thus a
difficulty presents itself as to the explanation of the three following
relationships:--(1) That of the Pterodactyles with carinate birds; (2) that
of the Dinosauria with struthious birds; (3) that of the carinate and
struthious birds with each other.
Either birds must have had two distinct origins whence they grew to their
present conformity, or the very same skeletal, and probably cerebral
characters must have spontaneously and independently arisen. Here is a
dilemma, either horn of which bears a threatening aspect to the exclusive
supporter of "Natural Selection," and between which it seems somewhat {72}
difficult to choose.
It has been suggested to me that this difficulty may be evaded by
considering pterodactyles and carinate birds as independent branches from
one side of an ancient common trunk, while similarly the Dinosauria and
struthious birds are taken to be independent branches from the other side
of the same common trunk; the two kinds of birds resembling each other so
much on account of their later development from that trunk as compared with
the development of the reptilian forms. But to this it may be replied that
the ancient common stock could not have had at one and the same time a
shoulder structure of _both kinds_. It must have been that of the
struthious birds or that of the carinate birds, or something different from
both. If it was that of the struthious birds, how did the pterodactyles and
carinate birds independently arrive at the very same divergent structure?
If it was that of the carinate birds, how did the struthious birds and
Dinosauria independently agree to differ? Finally, if it was something
different from either, how did the carinate birds and pterodactyles take on
independently one special common structure when disagreeing in so many;
while the struthious birds, agreeing in many points with the Dinosauria,
agree yet more with the carinate birds? Indeed by no arrangement of
branches from a stem can the difficulty be evaded.
Professor Huxley seems inclined[55] to cut the Gordian knot by considering
the shoulder structure of the pterodactyle as independently educed, and
having relation to physiology only. This conception is one which harmonizes
completely with the views here advocated, and with those of Mr. Herbert
Spencer, who also calls in direct modification to the aid of "Natural
Selection." That merely minute, indefinite variations in all directions
should unaided have independently built up the shoulder structure of {73}
the pterodactyles and carinate birds, and have laterally depressed their
optic lobes, at a time so far back as the deposition of the Oolite
strata,[56] is a coincidence of the highest improbability; but that an
innate power and evolutionary law, aided by the corrective action of
"Natural Selection," should have furnished like needs with like aids, is
not at all improbable. The difficulty does not tell against the theory of
evolution, but only against the specially Darwinian form of it. Now this
form has never been expressly adopted by Professor Huxley; so far from it,
in his lecture on this subject at the Royal Institution before referred to,
he observes,[57] "I can testify, from personal experience, it is possible
to have a complete faith in the general doctrine of evolution, and yet to
hesitate in accepting the Nebular, or the Uniformitarian, or the Darwinian
hypotheses in all their integrity and fulness."
[Illustration: THE ARCHEOPTERYX (of the Oolite strata).]
It is quite consistent, then, in the Professor to explain the {74}
difficulty as he does; but it would not be similarly so with an absolute
and pure Darwinian.
Yet stronger arguments of an analogous kind are, however, to be derived
from the highest organs of sense. In the most perfectly organized
animals--those namely which, like ourselves, possess a spinal column--the
internal organs of hearing consist of two more or less complex membranous
sacs (containing calcareous particles--otoliths), which are primitively or
permanently lodged in two chambers, one on each side of the cartilaginous
skull. The primitive cartilaginous cranium supports and protects the base
of the brain, and the auditory nerves pass from that brain into the
cartilaginous chambers to reach the auditory sacs. These complex
arrangements of parts could not have been evolved by "Natural Selection,"
_i.e._ by minute accidental variations, except by the action of such
through a vast period of time; nevertheless, it was fully evolved at the
time of the deposition of the upper Silurian rocks.
Cuttle-fishes (_Cephalopoda_) are animals belonging to the molluscous
primary division of the animal kingdom, which division contains animals
formed upon a type of structure utterly remote from that on which the
animals of the higher division provided with a spinal column are
constructed. And indeed no transitional form (tending even to bridge over
the chasm between these two groups) has ever yet been discovered, either
living or in a fossilized condition.[58]
Nevertheless, in the two-gilled Cephalopods (_Dibranchiata_) we find the
brain supported and protected by a cartilaginous cranium. In the base of
this cranium are two cartilaginous chambers. In each chamber is a
membranous sac containing an otolith, and the auditory nerves pass from the
cerebral ganglia into the cartilaginous chambers to reach the auditory
sacs. Moreover, it has been suggested by Professor Owen that {75}
sinuosities between processes projecting from the inner wall of each
chamber "seem to be the first rudiments of those which, in the higher
classes (_i.e._ in animals with a spinal column), are extended in the form
of canals and spiral chambers, within the substance of the dense nidus of
the labyrinth."[59]
[Illustration: CUTTLE-FISH.
A. Ventral aspect. B. Dorsal aspect.]
Here, then, we have a wonderful coincidence indeed; two highly complex
auditory organs, marvellously similar in structure, but which must
nevertheless have been developed in entire and complete independence one of
the other! It would be difficult to calculate the odds against the
independent occurrence and conservation of two such complex series of
merely accidental and minute haphazard variations. And it can never be {76}
maintained that the sense of hearing could not be efficiently subserved
otherwise than by such sacs, in cranial cartilaginous capsules so situated
in relation to the brain, &c.
Our wonder, moreover, may be increased when we recollect that the
two-gilled cephalopods have not yet been found below the lias, where they
at once abound; whereas the four-gilled cephalopods are Silurian forms.
Moreover, the absence is in this case significant in spite of the
imperfection of the geological record, because when we consider how many
individuals of various kinds of four-gilled cephalopods have been found, it
is fair to infer that at the least a certain small percentage of dibranchs
would also have left traces of their presence had they existed. Thus it is
probable that some four-gilled form was the progenitor of the dibranch
cephalopods. Now the four-gilled kinds (judging from the only existing
form, the nautilus) had the auditory organ in a very inferior condition of
development to what we find in the dibranch; thus we have not only evidence
of the independent high development of the organ in the former, but also
evidence pointing towards a certain degree of comparative rapidity in its
development.
Such being the case with regard to the organ of hearing, we have another
yet stronger argument with regard to the organ of sight, as has been well
pointed out by Mr. J. J. Murphy.[60] He calls attention to the fact that
the eye must have been perfected in at least "three distinct lines of
descent," alluding not only to the molluscous division of the animal
kingdom, and the division provided with a spinal column, but also to a
third primary division, namely, that which includes all insects, spiders,
crabs, &c., which are spoken of as Annulosa, and the type of whose
structure is as distinct from that of the molluscous type on the one hand,
as it is from that of the type with a spinal column (_i.e._ the vertebrate
type) on the other.
{77}
In the cuttle-fishes we find an eye even more completely constructed on the
vertebrate type than is the ear. Sclerotic, retina, choroid, vitreous
humour, lens, aqueous humour, all are present. The correspondence is
wonderfully complete, and there can hardly be any hesitation in saying that
for such an exact, prolonged, and correlated series of similar structures
to have been brought about in two independent instances by merely
indefinite and minute accidental variations, is an improbability which
amounts practically to impossibility. Moreover, we have here again the same
imperfection of the four-gilled cephalopod, as compared with the
two-gilled, and therefore (if the latter proceeded from the former) a
similar indication of a certain comparative rapidity of development.
Finally, and this is perhaps one of the most curious circumstances, the
process of formation appears to have been, at least in some respects, the
same in the eyes of these molluscous animals as in the eyes of vertebrates.
For in these latter the cornea is at first perforated, while different
degrees of perforation of the same part are presented by different adult
cuttle-fishes--large in the calamaries, smaller in the octopods, and
reduced to a minute foramen in the true cuttle-fish sepia.
Some may be disposed to object that the conditions requisite for effecting
vision are so rigid that similar results in all cases must be independently
arrived at. But to this objection it may well be replied that Nature
herself has demonstrated that there is no such necessity as to the details
of the process. For in the higher Annulosa, such as the dragon-fly, we meet
with an eye of an unquestionably very high degree of efficiency, but formed
on a type of structure only remotely comparable with that of the fish or
the cephalopod. The last-named animal might have had an eye as efficient as
that of a vertebrate, but formed on a distinct type, instead of being
another edition, as it were, of the very same structure.
In the beginning of this chapter examples have been given of the very {78}
diverse mode in which similar results have in many instances been arrived
at; on the other hand, we have in the fish and the cephalopod not only the
eye, but at one and the same time the ear also similarly evolved, yet with
complete independence.
Thus it is here contended that the similar and complex structures of both
the highest organs of sense, as developed in the vertebrates on the one
hand, and in the mollusks on the other, present us with residuary phenomena
for which "Natural Selection" alone is quite incompetent to account. And
that these same phenomena must therefore be considered as conclusive
evidence for the action of some other natural law or laws conditioning the
simultaneous and independent evolution of these harmonious and concordant
adaptations.
Provided with this evidence, it may be now profitable to enumerate other
correspondences, which are not perhaps in themselves inexplicable by
Natural Selection, but which are more readily to be explained by the action
of the unknown law or laws referred to--which action, as its necessity has
been demonstrated in one case, becomes _a priori_ probable in the others.
[Illustration: SKELETON OF AN ICHTHYOSAURUS.]
Thus the great oceanic Mammalia--the whales--show striking resemblances to
those prodigious, extinct, marine reptiles, the Ichthyosauria, and this not
only in structures readily referable to similarity of habit, but in such
matters as greatly elongated premaxillary bones, together with the
concealment of certain bones of the skull by other cranial bones. [Page 79]
Again, the aërial mammals, the bats, resemble those flying reptiles of the
secondary epoch, the pterodactyles; not only to a certain extent in the
breast-bone and mode of supporting the flying membrane, but also in the
proportions of different parts of the spinal column and the hinder (pelvic)
limbs.
Also bivalve shell-fish (_i.e._ creatures of the mussel, cockle, and oyster
class, which receive their name from the body being protected by a double
shell, one valve of which is placed on each side) have their two shells
united by one or two powerful muscles, which pass directly across from one
shell to the other, and which are termed "adductor muscles" because by
their contraction they bring together the valves and so close the shell.
[Illustration: CYTHERIDEA TOROSA.
[An ostracod (Crustacean), externally like a bivalve shell-fish
(Lamellibranch).]
Now there are certain animals which belong to the crab and lobster class
(Crustacea)--a class constructed on an utterly different type from that on
which the bivalve shell-fish are constructed--which present a very curious
approximation to both the form and, in a certain respect, the structure of
true bivalves. Allusion is here made to certain small Crustacea--certain
phyllopods and ostracods--which have the hard outer coat of their thorax so
modified as to look wonderfully like a bivalve shell, although its {80}
nature and composition are quite different. But this is by no means
all,--not only is there this external resemblance between the thoracic
armour of the crustacean and the bivalve shell, but the two sides of the
ostracod and phyllopod thorax are connected together also by an adductor
muscle!
[Illustration: A POLYZOON WITH BIRD'S-HEAD PROCESSES.]
{81}
The pedicellariæ of the echinus have been already spoken of, and the
difficulty as to their origin from minute, fortuitous, indefinite
variations has been stated. But structures essentially similar (called
avicularia, or "bird's-head processes") are developed from the surface of
the compound masses of certain of the highest of the polyp-like animals
(viz. the Polyzoa or, as they are sometimes called, the Bryozoa).
These compound animals have scattered over the surface of their bodies
minute processes, each of which is like the head of a bird, with an upper
and lower beak, the whole supported on a slender neck. The beak opens and
shuts at intervals, like the jaws of the pedicellariæ of the echinus, and
there is altogether, in general principle, a remarkable similarity between
the structures. Yet the echinus can have, at the best, none but the most
distant genetic relationship with the Polyzoa. We have here again therefore
complex and similar organs of diverse and independent origin.
[Illustration: BIRD'S-HEAD PROCESSES VERY GREATLY ENLARGED.]
In the highest class of animals (the Mammalia) we have almost always a
placental mode of reproduction, _i.e._ the blood of the foetus is placed in
nutritive relation with the blood of the mother by means of vascular
prominences. No trace of such a structure exists in any bird or in any
reptile, and yet it crops out again in certain sharks. There indeed it
might well be supposed to end, but, marvellous as it seems, it reappears in
very lowly creatures; namely, in certain of the ascidians, sometimes called
tunicaries or sea-squirts. [Page 82]
Now, if we were to concede that the ascidians were the common ancestors[61]
of both these sharks and of the higher mammals, we should be little, if
any, nearer to an explanation of the phenomenon by means of "Natural
Selection," for in the sharks in question the vascular prominences are
developed from one foetal structure (the umbilical vesicle), while in the
higher mammals they are developed from quite another part, viz. the
allantois.
[Illustration: Upper Figure--ANTECHINUS MINUTISSIMUS (_implacental_).
Lower Figure--MUS DELICATULUS (_placental_).]
So great, however, is the number of similar, but apparently independent,
structures, that we suffer from a perfect _embarras de richesses_. Thus,
for example, we have the convoluted windpipe of the sloth, reminding us{83}
of the condition of the windpipe in birds; and in another mammal, allied to
the sloth, namely the great ant-eater (Myrmecophaga), we have again an
ornithic character in its horny gizzard-like stomach. In man and the
highest apes the cæcum has a vermiform appendix, as it has also in the
wombat!
Also the similar forms presented by the crowns of the teeth in some seals,
in certain sharks, and in some extinct Cetacea may be referred to; as also
the similarity of the beak in birds, some reptiles, in the tadpole, and
cuttle-fishes. As to entire external form, may be adduced the wonderful
similarity between a true mouse (_Mus delicatulus_) and a small marsupial,
pointed out by Mr. Andrew Murray in his work on the "Geographical
Distribution of Mammals," p. 53, and represented in the frontispiece by
figures copied from Gould's "Mammals of Australia;" but instances enough
for the present purpose have been already quoted.
Additional reasons for believing that similarity of structure is produced
by other causes than merely by "Natural Selection" are furnished by certain
facts of zoological geography, and by a similarity in the mode of variation
being sometimes extended to several species of a genus, or even to widely
different groups; while the restriction and the limitation of such
similarity are often not less remarkable. Thus Mr. Wallace says,[62] as to
local influence: "Larger or smaller districts, or even single islands, give
a special character to the majority of their Papilionidæ. For instance:--1.
The species of the Indian region (Sumatra, Java, and Borneo) are almost
invariably smaller than the allied species inhabiting Celebes and the
Moluccas. 2. The species of New Guinea and Australia are also, though in a
less degree, smaller than the nearest species or varieties of the Moluccas.
3. In the Moluccas themselves the species of Amboyna are the largest. 4.
The species of Celebes equal or even surpass in size those of Amboyna. {84}
5. The species and varieties of Celebes possess a striking character in the
form of the anterior wings, different from that of the allied species and
varieties of all the surrounding islands. 6. Tailed species in India or the
Indian region become tailless as they spread eastward through the
Archipelago. 7. In Amboyna and Ceram the females of several species are
dull-coloured, while in the adjacent islands they are more brilliant."
Again:[63] "In Amboyna and Ceram the female of the large and handsome
_Ornithoptera Helena_ has the large patch on the hind wings constantly of a
pale dull ochre or buff colour; while in the scarcely distinguishable
varieties from the adjacent islands, of Bouru and New Guinea, it is of a
golden yellow, hardly inferior in brilliancy to its colour in the male sex.
The female of _Ornithoptera Priamus_ (inhabiting Amboyna and Ceram
exclusively) is of a pale dusky brown tint, while in all the allied species
the same sex is nearly black, with contracted white markings. As a third
example, the female of _Papilio Ulysses_ has the blue colour obscured by
dull and dusky tints, while in the closely allied species from the
surrounding islands, the females are of almost as brilliant an azure blue
as the males. A parallel case to this is the occurrence, in the small
islands of Goram, Matabello, Ké, and Aru, of several distinct species of
Euploea and Diadema, having broad bands or patches of white, which do not
exist in any of the allied species from the larger islands. These facts
seem to indicate some local influence in modifying colour, as
unintelligible and almost as remarkable as that which has resulted in the
modifications of form previously described."
After endeavouring to explain some of the facts in a way to be noticed
directly, Mr. Wallace adds:[64] "But even the conjectural explanation now
given fails us in the other cases of local modification. Why the species of
the Western Islands should be smaller than those further east; why those of
Amboyna should exceed in size those of Gilolo and New Guinea; why the {85}
tailed species of India should begin to lose that appendage in the islands,
and retain no trace of it on the borders of the Pacific; and why, in three
separate cases, the females of Amboyna species should be less gaily attired
than the corresponding females of the surrounding islands, are questions
which we cannot at present attempt to answer. That they depend, however, on
some general principle is certain, because analogous facts have been
observed in other parts of the world. Mr. Bates informs me that, in three
distinct groups, Papilios, which, on the Upper Amazon, and in most other
parts of South America, have spotless upper wings, obtain pale or white
spots at Pará and on the Lower Amazon, and also that the Æneas group of
Papilios never have tails in the equatorial regions and the Amazon valley,
but gradually acquire tails in many cases as they range towards the
northern or southern tropic. Even in Europe we have somewhat similar facts,
for the species and varieties of butterflies peculiar to the Island of
Sardinia are generally smaller and more deeply coloured than those of the
mainland, and the same has been recently shown to be the case with the
common tortoiseshell butterfly in the Isle of Man; while _Papilio
Hospiton_, peculiar to the former island, has lost the tail, which is a
prominent feature of the closely allied _P. Machaon_.
"Facts of a similar nature to those now brought forward would no doubt be
found to occur in other groups of insects, were local faunas carefully
studied in relation to those of the surrounding countries; and they seem to
indicate that climate and other physical causes have, in some cases, a very
powerful effect in modifying specific form and colour, and thus directly
aid in producing the endless variety of nature."
[Illustration: OUTLINES OF WINGS OF BUTTERFLIES OF CELEBES COMPARED WITH
THOSE OF ALLIED SPECIES ELSEWHERE.
Outer outline, _Papilio gigon_, of Celebes. Inner outline, _P. demolion_,
of Singapore and Java.--2. Outer outline, _P. miletus_, of Celebes. Inner
outline, _P. sarpedon_, India.--3. Outer outline, _Tachyris zarinda_,
Celebes. Inner outline, _T. nero_.]
With regard to butterflies of Celebes belonging to different families, they
present "a peculiarity of outline which distinguishes them at a glance from
those of any other part of the world:"[65] it is that the upper wings {86}
are generally more elongated and the anterior margin more curved. Moreover,
there is, in most instances, near the base an abrupt bend or elbow, which
in some species is very conspicuous. Mr. Wallace endeavours to explain {87}
this phenomenon by the supposed presence at some time of special
persecutors of the modified forms, supporting the opinion by the remark
that small, obscure, very rapidly flying and mimicked kinds have not had
the wing modified. Such an enemy occasioning increased powers of flight, or
rapidity in turning, he adds, "one would naturally suppose to be an
insectivorous bird; but it is a remarkable fact that most of the genera of
fly-catchers of Borneo and Java on the one side, and of the Moluccas on the
other, are almost entirely absent from Celebes. Their place seems to be
supplied by the caterpillar-catchers, of which six or seven species are
known from Celebes, and are very numerous in individuals. We have no
positive evidence that these birds pursue butterflies on the wing, but it
is highly probable that they do so when other food is scarce. Mr. Bates
suggested to me that the larger dragon-flies prey upon butterflies, but I
did not notice that they were more abundant in Celebes than elsewhere."[66]
Now, every opinion or conjecture of Mr. Wallace is worthy of respectful and
attentive consideration, but the explanation suggested and before referred
to hardly seems a satisfactory one. What the past fauna of Celebes may have
been is as yet conjectural. Mr. Wallace tells us that now there is a
remarkable _scarcity_ of fly-catchers, and that their place is supplied by
birds of which it can only be said that it is "highly probable" that they
chase butterflies "when other food is scarce." The quick eye of Mr. Wallace
failed to detect them in the act, as also to note any unusual abundance of
other insectivorous forms, which therefore, considering Mr. Wallace's zeal
and powers of observation, we may conclude do not exist. Moreover, even if
there ever has been an abundance of such, it is by no means certain that
they would have succeeded in producing the conformation in question, for
the effect of this peculiar curvature on flight is by no means clear. We
have here, then, a structure hypothetically explained by an uncertain {88}
property induced by a cause the presence of which is only conjectural.
Surely it is not unreasonable to class this instance with the others before
given, in which a common modification of form or colour coexists with a
certain geographical distribution quite independently of the destructive
agencies of animals. If physical causes connected with locality can
abbreviate or annihilate the tails of certain butterflies, why may not
similar causes produce an elbow-like prominence on the wings of other
butterflies? There are many such instances of simultaneous modification.
Mr. Darwin himself[67] quotes Mr. Gould as believing that birds of the same
species are more brightly coloured under a clear atmosphere, than when
living on islands or near the coast. Mr. Darwin also informs us that
Wollaston is convinced that residence near the sea affects the colour of
insects; and finally, that Moquin-Tandon gives a list of plants which, when
growing near the sea-shore, have their leaves in some degree fleshy, though
not so elsewhere. In his work on "Animals and Plants under
Domestication,"[68] Mr. Darwin refers to M. Costa as having (in _Bull. de
la Soc. Imp. d'Acclimat_. tome viii. p. 351) stated "that young shells
taken from the shores of England and placed in the Mediterranean at once
altered their manner of growth, and formed prominent diverging rays _like
those on the shells of the proper Mediterranean oyster_;" also to Mr.
Meehan, as stating (_Proc. Acad. Nat. Sc. of Philadelphia_, Jan. 28, 1862)
"that twenty-nine kinds of American trees all differ from their nearest
European allies in _a similar manner_, leaves less toothed, buds and seeds
smaller, fewer branchlets," &c. These are striking examples indeed!
But cases of simultaneous and similar modifications abound on all sides.
Even as regards our own species there is a very generally admitted opinion
that a new type has been developed in the United States, and this in about
a couple of centuries only, and in a vast multitude of individuals of {89}
diverse ancestry. The instances here given, however, must suffice, though
more could easily be added.
[Illustration: THE GREAT SHIELDED GRASSHOPPER.]
It may be well now to turn to groups presenting similar variations, not
through, but independently of, geographical distribution, and, as far as we
know, independently of conditions other than some peculiar nature and
tendency (as yet unexplained) common to members of such groups, which
nature and tendency seem to induce them to vary in certain definite lines
or directions which are different in different groups. Thus with regard to
the group of insects, of which the walking leaf is a member, Mr. Wallace
observes:[69] "The _whole family_[70] of the Phasmidæ, or spectres, to
which this insect belongs, is more or less imitative, and a great number of
the species are called 'walking-stick insects,' from their singular {90}
resemblance to twigs and branches."
[Illustration: THE SIX-SHAFTED BIRD OF PARADISE.]
Again, Mr. Wallace[71] tells us of no less than four kinds of orioles,
which birds mimic, more or less, four species of a genus of honey-suckers,
the weak orioles finding their profit in being mistaken by certain birds of
prey for the strong, active, and gregarious honey-suckers. Now, many other
birds would be benefited by similar mimicry, which is none the less
confined, in this part of the world, to the oriole genus. It is true that
the absence of mimicry in other forms may be explained by their possessing
some other (as yet unobserved) means of preservation. But it is
nevertheless remarkable, not so much that one species should mimic, as that
no less than four should do so in different ways and degrees, all these{91}
four belonging to _one and the same genus_.
[Illustration: THE LONG-TAILED BIRD OF PARADISE.]
In other cases, however, there is not even the help of protective action to
account for the phenomenon. Thus we have the wonderful birds of
Paradise,[72] which agree in developing plumage unequalled in beauty, but a
beauty which, as to details, is of different kinds, and produced in
different ways in different species. To develop "beauty and singularity of
plumage" is a character of the group, but not of any one definite kind, to
be explained merely by inheritance.
{92}
[Illustration]
Again, we have the very curious horned flies,[73] which agree indeed in a
common peculiarity, but in one singularly different in detail, in different
species and not known to have any protecting effect.
Amongst plants, also, we meet with the same peculiarity. The great group of
Orchids presents a number of species which offer strange and bizarre {93}
approximations to different animal forms, and which have often the
appearance of cases of mimicry, as it were in an incipient stage.
[Illustration: HORNED FLIES.]
[Illustration: THE MAGNIFICENT BIRD OF PARADISE.]
The number of similar instances which could be brought forward from amongst
animals and plants is very great, but the examples given are, it is {94}
hoped, amply sufficient to point towards the conclusion which other facts
will, it is thought, establish, viz. that there are causes operating (in
the evocation of these harmonious diverging resemblances) other than
"Natural Selection," or heredity, and other even than merely geographical,
climatal, or any simply external conditions.
Many cases have been adduced of striking likenesses between different
animals, not due to inheritance; but this should be the less surprising, in
that the very same individual presents us with likenesses between different
parts of its body (_e.g._, between the several joints of the backbone),
which are certainly not so explicable. This, however, leads to a rather
large subject, which will be spoken of in the eighth chapter of the present
work. Here it will be enough to affirm (leaving the proof of the assertion
till later) that parts are often homologous which have no direct genetic
relationship,--a fact which harmonizes well with the other facts here
given, but which "Natural Selection," pure and simple, seems unable to
explain.
But surely the independent appearance of similar organic forms is what we
might expect, _a priori_, from the independent appearance of similar
inorganic ones. As Mr. G. H. Lewes well observes,[74] "We do not suppose
the carbonates and phosphates found in various parts of the globe--we do
not suppose that the families of alkaloids and salts have any nearer
kinship than that which consists in the similarity of their elements, and
the conditions of their combination. Hence, in organisms, as in salts,
morphological identity may be due to a community of causal connexion,
rather than community of descent.
"Mr. Darwin justly holds it to be incredible that individuals identically
the same should have been produced through Natural Selection from parents
_specifically distinct_, but he will not deny that identical forms may
issue from parents _genetically distinct_, when these parent forms and {95}
the conditions of production are identical. To deny this would be to deny
the law of causation."
Professor Huxley has, however, suggested[75] that such mineral identity may
be explained by applying also to minerals a law of descent; that is, by
considering such similar forms as the descendants of atoms which inhabited
one special part of the primitive nebular cosmos, each considerable space
of which may be supposed to have been under the influence of somewhat
different conditions.
Surely, however, there can be no real parity between the relationship of
existing minerals to nebular atoms, and the relationship of existing
animals and plants to the earliest organisms. In the first place, the
latter have produced others by generative multiplication, which mineral
atoms never did. In the second, existing animals and plants spring from the
living tissues of preceding animals and plants, while existing minerals
spring from the chemical affinity of separate elements. Carbonate of soda
is not formed, by a process of reproduction, from other carbonate of soda,
but directly by the suitable juxtaposition of carbon, oxygen, and sodium.
Instead of approximating animals and minerals in the mode suggested, it may
be that they are to be approximated in quite a contrary fashion; namely, by
attributing to mineral species an internal innate power. For, as we must
attribute to each elementary atom an innate power and tendency to form
(under the requisite external conditions) certain unions with other atoms,
so we may attribute to certain mineral species--as crystals--an innate
power and tendency to exhibit (the proper conditions being supplied) a
definite and symmetrical external form. The distinction between animals and
vegetables on the one hand, and minerals on the other, is that, while in
the organic world close similarity is the result sometimes of inheritance,
sometimes of direct production independently of parental action, in the{96}
inorganic world the latter is the constant and only mode in which such
similarity is produced.
When we come to consider the relations of species to space--in other words,
the geographical distribution of organisms--it will be necessary to return
somewhat to the subject of the independent origin of closely similar forms,
in regard to which some additional remarks will be found towards the end of
the seventh chapter.
In this third chapter an effort has been made to show that while on the
Darwinian theory concordant variations are extremely improbable, yet Nature
presents us with abundant examples of such; the most striking of which are,
perhaps, the higher organs of sense. Also that an important influence is
exercised by conditions connected with geographical distribution, but that
a deeper-seated influence is at work, which is hinted at by those special
tendencies in definite directions, which are the properties of certain
groups. Finally, that these facts, when taken together, afford strong
evidence that "Natural Selection" has not been the exclusive or predominant
cause of the various organic structural peculiarities. This conclusion has
also been re-enforced by the consideration of phenomena presented to us by
the inorganic world. [Page 97]
* * * * *
CHAPTER IV.
MINUTE AND GRADUAL MODIFICATIONS.
There are difficulties as to minute modifications, even if not
fortuitous.--Examples of sudden and considerable modifications of
different kinds.--Professor Owen's view.--Mr. Wallace.--Professor
Huxley.--Objections to sudden
changes.--Labyrinthodont.--Potto.--Cetacea.--As to origin of bird's
wing.--Tendrils of climbing plants.--Animals once supposed to be
connecting links.--Early specialization of
structure.--Macrauchenia.--Glyptodon.--Sabre-toothed
tiger.--Conclusion.
Not only are there good reasons against the acceptance of the exclusive
operation of "Natural Selection" as the one means of specific origination,
but there are difficulties in the way of accounting for such origination by
the sole action of modifications which are infinitesimal and minute,
whether fortuitous or not.
Arguments may yet be advanced in favour of the view that new species have
from time to time manifested themselves with suddenness, and by
modifications appearing at once (as great in degree as are those which
separate _Hipparion_ from _Equus_), the species remaining stable in the
intervals of such modifications: by stable being meant that their
variations only extend for a certain degree in various directions, like
oscillations in a stable equilibrium. This is the conception of Mr.
Galton,[76] who compares the development of species with a many {98}
facetted spheroid tumbling over from one facet, or stable equilibrium, to
another. The existence of internal conditions in animals corresponding with
such facets is denied by pure Darwinians, but it is contended in this work,
though not in this chapter, that something may also be said for their
existence.
The considerations brought forward in the last two chapters, namely, the
difficulties with regard to incipient and closely similar structures
respectively, together with palæontological considerations to be noticed
later, appear to point strongly in the direction of sudden and considerable
changes. This is notably the case as regards the young oysters already
mentioned, which were taken from the shores of England and placed in the
Mediterranean, and at once altered their mode of growth and formed
prominent diverging rays, _like those of the proper Mediterranean oyster_;
as also the twenty-nine kinds of American trees, all differing from their
nearest European allies _similarly_--"leaves less toothed, buds and seeds
smaller, fewer branchlets," &c. To these may be added other facts given by
Mr. Darwin. Thus he says, "that climate, to a certain extent, directly
modifies the form of dogs."[77]
The Rev. R. Everett found that setters at Delhi, though most carefully
paired, yet had young with "nostrils more contracted, noses more pointed,
size inferior, and limbs more slender." Again, cats at Mombas, on the coast
of Africa, have short stiff hairs instead of fur, and a cat at Algoa Bay,
when left only eight weeks at Mombas, "underwent a complete metamorphosis,
having parted with its sandy-coloured fur."[78] The conditions of life seem
to produce a considerable effect on horses, and instances are given by Mr.
Darwin of pony breeds[79] having independently arisen in different parts of
the world, possessing a certain similarity in their physical {99}
conditions. Also changes due to climate may be brought about at once in a
second generation, though no appreciable modification is shown by the
first. Thus "Sir Charles Lyell mentions that some Englishmen, engaged in
conducting the operations of the Real del Monte Company in Mexico, carried
out with them some greyhounds of the best breed to hunt the hares which
abound in that country. It was found that the greyhounds could not support
the fatigues of a long chase in this attenuated atmosphere, and before they
could come up with their prey they lay down gasping for breath; but these
same animals have produced whelps, which have grown up, and are not in the
least degree incommoded by the want of density in the air, but run down the
hares with as much ease as do the fleetest of their race in this
country."[80]
We have here no action of "Natural Selection;" it was not that certain
puppies happened accidentally to be capable of enduring more rarefied air,
and so survived, but the offspring were directly modified by the action of
surrounding conditions. Neither was the change elaborated by minute
modifications in many successive generations, but appeared at once in the
second.
With regard once more to sudden alterations of form, Nathusius is said to
state positively as to pigs,[81] that the result of common experience and
of his experiments was that rich and abundant food, given during youth,
tends by some direct action to make the head broader and shorter. Curious
jaw appendages often characterize Normandy pigs, according to M. Eudes
Deslongchamps. Richardson figures these appendages on the old "Irish
greyhound pig," and they are said by Nathusius to appear occasionally in
all the long-eared races. Mr. Darwin observes,[82] "As no wild pigs are
known to have analogous appendages, we have at present no reason to {100}
suppose that their appearance is due to reversion; and if this be so, we
are forced to admit that somewhat complex, though apparently useless
structures may be suddenly developed without the aid of selection." Again,
"Climate directly affects the thickness of the skin and hair" of
cattle.[83] In the English climate an individual Porto Santo rabbit[84]
recovered the proper colour of its fur in rather less than four years. The
effect of the climate of India on the turkey is considerable. Mr. Blyth[85]
describes it as being much degenerated in size, "utterly incapable of
rising on the wing," of a black colour, and "with long pendulous appendages
over the beak enormously developed." Mr. Darwin again tells us that there
has suddenly appeared in a bed of common broccoli a peculiar variety,
faithfully transmitting its newly acquired and remarkable characters;[86]
also that there have been a rapid transformation and transplantation of
American varieties of maize with a European variety;[87] that certainly
"the Ancon and Manchamp breeds of sheep," and that (all but certainly)
Niata cattle, turnspit and pug dogs, jumper and frizzled fowls, short-faced
tumbler pigeons, hook-billed ducks, &c., and a multitude of vegetable
varieties, have suddenly appeared in nearly the same state as we now see
them.[88] Lastly, Mr. Darwin tells us, that there has been an occasional
development (in five distinct cases) in England of the "japanned" or
"black-shouldered peacock" (_Pavo nigripennis_), a distinct species,
according to Dr. Sclater,[89] yet arising in Sir J. Trevelyan's flock
composed entirely of the common kind, and increasing, "_to the extinction
of the previously existing breed_."[90] Mr. Darwin's only explanation of
the phenomena (on the supposition of the species being distinct) is by{101}
reversion, owing to a supposed ancestral cross. But he candidly admits, "I
have heard of no other such case in the animal or vegetable kingdom." On
the supposition of its being only a variety, he observes, "The case is the
most remarkable ever recorded of the abrupt appearance of a new form, which
so closely resembles a true species, that it has deceived one of the most
experienced of living ornithologists."
As to plants, M. C. Naudin[91] has given the following instances of the
sudden origination of apparently permanent forms. "The first case mentioned
is that of a poppy, which took on a remarkable variation in its fruit--a
crown of secondary capsules being added to the normal central capsule. A
field of such poppies was grown, and M. Göppert, with seed from this field,
obtained still this monstrous form in great quantity. Deformities of ferns
are sometimes sought after by fern-growers. They are now always obtained by
taking spores from the abnormal parts of the monstrous fern; from which
spores ferns presenting the same peculiarities invariably grow.... The most
remarkable case is that observed by Dr. Godron, of Nancy. In 1861 that
botanist observed, amongst a sowing of _Datura tatula_, the fruits of which
are very spinous, a single individual of which the capsule was perfectly
smooth. The seeds taken from this plant all furnished plants having the
character of this individual. The fifth and sixth generations are now
growing without exhibiting the least tendency to revert to the spinous
form. More remarkable still, when crossed with the normal _Datura tatula_,
hybrids were produced, which, in the second generation, reverted to the
original types, as true hybrids do."
There are, then, abundant instances to prove that considerable {102}
modifications may suddenly develop themselves, either due to external
conditions or to obscure internal causes in the organisms which exhibit
them. Moreover, these modifications, from whatever cause arising, are
capable of reproduction--the modified individuals "breeding true."
The question is whether new species have been developed by non-fortuitous
variations which are insignificant and minute, or whether such variations
have been comparatively sudden, and of appreciable size and importance?
Either hypothesis will suit the views here maintained equally well (those
views being opposed only to fortuitous, indefinite variations), but the
latter is the more remote from the Darwinian conception, and yet has much
to be said in its favour.
Professor Owen considers, with regard to specific origination, that natural
history "teaches that the change would be sudden and considerable: it
opposes the idea that species are transmitted by minute and slow
degrees."[92] "An innate tendency to deviate from parental type, operating
through periods of adequate duration," being "the most probable nature, or
way of operation of the secondary law, whereby species have been derived
one from the other."[93]
Now, considering the number of instances adduced of sudden modifications in
domestic animals, it is somewhat startling to meet with Mr. Darwin's
dogmatic assertion that it is "a _false belief_" that natural species have
often originated in the same abrupt manner. The belief _may_ be false, but
it is difficult to see how its falsehood can be positively asserted.
It is demonstrated by Mr. Darwin's careful weighings and measurements,
that, though little used parts in domestic animals get reduced in weight
and somewhat in size, yet that they show no inclination to become truly
"rudimentary structures." Accordingly he asserts[94] that such {103}
rudimentary parts are formed "suddenly, by arrest of development" in
domesticated animals, but in wild animals slowly. The latter assertion,
however, is a _mere assertion_; necessary, perhaps, for the theory of
"Natural Selection," but as yet unproved by facts.
But why should not these changes take place suddenly in a state of nature?
As Mr. Murphy says,[95] "It may be true that we have no evidence of the
origin of wild species in this way. But this is not a case in which
negative evidence proves anything. We have never witnessed the origin of a
wild species by any process whatever; and if a species were to come
suddenly into being in the wild state, as the Ancon Sheep did under
domestication, how could you ascertain the fact? If the first of a
newly-begotten species were found, the fact of its discovery would tell
nothing about its origin. Naturalists would register it as a very rare
species, having been only once met with, but they would have no means of
knowing whether it were the first or the last of its race."
To this Mr. Wallace has replied (in his review of Mr. Murphy's work in
_Nature_[96]), by objecting that sudden changes could very rarely be
useful, because each kind of animal is a nicely balanced and adjusted
whole, any one sudden modification of which would in most cases be hurtful
unless accompanied by other simultaneous and harmonious modifications. If,
however, it is not unlikely that there is an innate tendency to deviate at
certain times, and under certain conditions, it is no more unlikely that
that innate tendency should be an harmonious one, calculated to
simultaneously adjust the various parts of the organism to their new
relations. The objection as to the sudden abortion of rudimentary organs
may be similarly met.
Professor Huxley seems now disposed to accept the, at least {104}
occasional, intervention of sudden and considerable variations. In his
review of Professor Kölliker's[97] criticisms, he himself says,[98] "We
greatly suspect that she" (_i.e._ Nature) "does make considerable jumps in
the way of variation now and then, and that these saltations give rise to
some of the gaps which appear to exist in the series of known forms."
[Illustration: MUCH ENLARGED HORIZONTAL SECTION OF THE TOOTH OF A
LABYRINTHODON.]
In addition to the instances brought forward in the second chapter against
the minute action of Natural Selection, may be mentioned such {105}
structures as the wonderfully folded teeth of the labyrinthodonts. The
marvellously complex structure of these organs is not merely unaccountable
as due to Natural "Selection," but its production by insignificant
increments of complexity is hardly less difficult to comprehend.
Similarly the aborted index of the Potto (_Perodicticus_) is a structure
not likely to have been induced by minute changes; while, as to "Natural
Selection," the reduction of the fore-finger to a mere rudiment is
inexplicable indeed! "How this mutilation can have aided in the struggle
for life, we must confess, baffles our conjectures on the subject; for that
any very appreciable gain to the individual can have resulted from the
slightly lessened degree of required nourishment thence resulting (_i.e._
from the suppression), seems to us to be an almost absurd proposition."[99]
[Illustration: HAND OF THE POTTO (PERODICTICUS), FROM LIFE.]
Again, to anticipate somewhat, the great group of whales (Cetacea) was
fully developed at the deposition of the Eocene strata. On the other hand,
we may pretty safely conclude that these animals were absent as late as the
latest secondary rocks, so that their development could not have been so
very slow, unless geological time is (although we shall presently see there
are grounds to believe it is not) practically infinite. It is quite true
that it is, in general, very unsafe to infer the absence of any animal
forms during a certain geological period, because no remains of them {106}
have as yet been found in the strata then deposited: but in the case of the
Cetacea it is safe to do so; for, as Sir Charles Lyell remarks,[100] they
are animals, the remains of which are singularly likely to have been
preserved had they existed, in the same way that the remains were preserved
of the Ichthyosauri and Plesiosauri, which appear to have represented the
Cetacea during the secondary geological period.
[Illustration: SKELETON OF A PLESIOSAURUS.]
As another example, let us take the origin of wings, such as exist in
birds. Here we find an arm, the bones of the hand of which are atrophied
and reduced in number, as compared with those of most other Vertebrates.
Now, if the wing arose from a terrestrial or subaërial organ, this abortion
of the bones could hardly have been serviceable--hardly have preserved
individuals in the struggle for life. If it arose from an aquatic organ,
like the wing of the penguin, we have then a singular divergence from the
ordinary vertebrate fin-limb. In the ichthyosaurus, in the plesiosaurus, in
the whales, in the porpoises, in the seals, and in others, we have
shortening of the bones, but no reduction in the number either of the
fingers or of their joints, which are, on the contrary, multiplied in
Cetacea and the ichthyosaurus. And even in the turtles we have eight carpal
bones and five digits, while no finger has less than two phalanges. It{107}
is difficult, then, to believe that the Avian limb was developed in any
other way than by a comparatively sudden modification of a marked and
important kind.
[Illustration: SKELETON OF AN ICHTHYOSAURUS.]
How, once more, can we conceive the peculiar actions of the tendrils of
some climbing plants to have been produced by minute modifications? These,
according to Mr. Darwin,[101] oscillate till they touch an object, and then
embrace it. It is stated by that observer, "that a thread weighing no more
than the thirty-second of a grain, if placed on the tendril of the
_Passiflora gracilis_, will cause it to bend; and merely to touch the
tendril with a twig causes it to bend; but if the twig is at once removed,
the tendril soon straightens itself. But the contact of other tendrils of
the plant, or of the falling of drops of rain, do not produce these
effects."[102] But some of the zoological and anatomical discoveries of
late years tend rather to diminish than to augment the evidence in favour
of minute and gradual modification. Thus all naturalists now admit that
certain animals, which were at one time supposed to be connecting links
between groups, belong altogether to one group, and not at all to the
other. For example, the aye-aye[103] (_Chiromys Madagascariensis_). {108}
was till lately considered to be allied to the squirrels, and was often
classed with them in the rodent order, principally on account of its
dentition; at the same time that its affinities to the lemurs and apes were
admitted. The thorough investigation into its anatomy that has now been
made, demonstrates that it has no more essential affinity to rodents than
any other lemurine creature has.
[Illustration: THE AYE-AYE.]
Bats were, by the earliest observers, naturally supposed to have a close
relationship to birds, and cetaceans to fishes. It is almost superfluous to
observe that all now agree that these mammals make not even an approach to
either one or other of the two inferior classes.
{109}
In the same way it has been recently supposed that those extinct flying
saurians, the pterodactyles, had an affinity with birds more marked than
any other known animals. Now, however, as has been said earlier, it is
contended that not only had they no such close affinity, but that other
extinct reptiles had a far closer one.
The _amphibia_ (_i.e._ frogs, toads, and efts) were long considered (and
are so still by some) to be reptiles, showing an affinity to fishes. It now
appears that they form with the latter one great group--the ichthyopsida of
Professor Huxley--which differs widely from reptiles; while its two
component classes (fishes and amphibians) are difficult to separate from
each other in a thoroughly satisfactory manner.
If we admit the hypothesis of gradual and minute modification, the
succession of organisms on this planet must have been a progress from the
more general to the more special, and no doubt this has been the case in
the majority of instances. Yet it cannot be denied that some of the most
recently formed fossils show a structure singularly more generalized than
any exhibited by older forms; while others are more specialized than are
any allied creatures of the existing creation.
A notable example of the former circumstance is offered by macrauchenia--a
hoofed animal, which was at first supposed to be a kind of great llama
(whence its name)--the llama being a ruminant, which, like all the rest,
has two toes to each foot. Now hoofed animals are divisible into two very
distinct series, according as the number of functional toes on each hind
foot is odd or even. And many other characters are found to go with this
obvious one. Even the very earliest Ungulata show this distinction, which
is completely developed and marked even in the Eocene palæotherium and
anoplotherium found in Paris by Cuvier. The former of these has the toes
odd (perissodactyle), the other has them even (artiodactyle).
Now, the macrauchenia, from the first relics of it which were found, {110}
was thought to belong, as has been said, to the even-toed division.
Subsequent discoveries, however, seemed to give it an equal claim to rank
amongst the perissodactyle forms. Others again inclined the balance of
probability towards the artiodactyle. Finally, it appears that this very
recently extinct beast presents a highly generalized type of structure,
uniting in one organic form both artiodactyle and perissodactyle
characters, and that in a manner not similarly found in any other known
creature living, or fossil. At the same time the differentiation of
artiodactyle and perissodactyle forms existed as long ago as in the period
of the Eocene ungulata, and that in a marked degree, as has been before
observed.
Again, no armadillo _now living_ presents nearly so remarkable a speciality
of structure as was possessed by the _extinct_ glyptodon. In that singular
animal the spinal column had most of its joints fused together, forming a
rigid cylindrical rod, a modification, as far as yet known, absolutely
peculiar to it.
[Illustration: DENTITION OF THE SABRE-TOOTHED TIGER (MACHAIRODUS).]
In a similar way the _extinct_ machairodus, or sabre-toothed tiger, is
characterized by a more highly differentiated and specially carnivorous
dentition than is shown by any predacious beast of the _present day_. {111}
The specialization is of this kind. The grinding teeth (or molars) of
beasts are divided into premolars and true molars. The premolars are molars
which have deciduous vertical predecessors (or milk teeth), and any which
are in front of such, _i.e._ between such and the canine tooth. The true
molars are those placed behind the molars having deciduous vertical
predecessors. Now, as a dentition becomes more distinctly carnivorous, so
the hindmost molars and the foremost premolars disappear. In the existing
cats this process is carried so far that in the upper jaw only one true
molar is left on each side. In the machairodus there is no upper true molar
at all, while the premolars are reduced to two, there being only these two
teeth above, on each side, behind the canine.
Now, with regard to these instances of early specialization, as also with
regard to the changed estimate of the degrees of affinity between forms, it
is not pretended for a moment that such facts are irreconcilable with
"Natural Selection." Nevertheless, they point in an opposite direction. Of
course not only is it conceivable that certain antique types arrived at a
high degree of specialization and then disappeared; but it is manifest they
did do so. Still the fact of this early degree of excessive specialization
tells to a certain, however small, extent against a progress through
excessively minute steps, whether fortuitous or not; as also does the
distinctness of forms formerly supposed to constitute connecting links.
For, it must not be forgotten, that if species have manifested themselves
generally by gradual and minute modifications, then the absence, not in one
but in _all cases_, of such connecting links, is a phenomenon which remains
to be accounted for.
It appears then that, apart from fortuitous changes, there are certain
difficulties in the way of accepting extremely minute modifications of any
kind, although these difficulties may not be insuperable. Something, at all
events, is to be said in favour of the opinion that sudden and {112}
appreciable changes have from time to time occurred, however they may have
been induced. Marked _races_ have undoubtedly so arisen (some striking
instances having been here recorded), and it is at least conceivable that
such may be the mode of _specific_ manifestation generally, the possible
conditions as to which will be considered in a later chapter. [Page 113]
* * * * *
CHAPTER V.
AS TO SPECIFIC STABILITY.
What is meant by the phrase "specific stability;" such stability to be
expected _a priori_, or else considerable changes at once.--Rapidly
increasing difficulty of intensifying race characters; alleged causes
of this phenomenon; probably an internal cause co-operates.--A certain
definiteness in variations.--Mr. Darwin admits the principle of
specific stability in certain cases of unequal variability.--The
goose.--The peacock.--The guinea fowl.--Exceptional causes of variation
under domestication.--Alleged tendency to
reversion.--Instances.--Sterility of hybrids.--Prepotency of pollen of
same species, but of different race.--Mortality in young gallinaceous
hybrids.--A bar to intermixture exists
somewhere.--Guinea-pigs.--Summary and conclusion.
As was observed in the preceding chapters, arguments may yet be advanced in
favour of the opinion that species are stable (at least in the intervals of
their comparatively sudden successive manifestations); that the organic
world consists, according to Mr. Galton's before-mentioned conception, of
many facetted spheroids, each of which can repose upon any one facet, but,
when too much disturbed, rolls over till it finds repose in stable
equilibrium upon another and distinct facet. Something, it is here
contended, may be urged, in favour of the existence of such facets--of such
intermitting conditions of stable equilibrium.
A view as to the stability of species, in the intervals of change, has been
well expressed in an able article, before quoted from, as follows:[104]--"A
given animal or plant appears to be contained, as it were, within a {114}
sphere of variation: one individual lies near one portion of the surface;
another individual, of the same species, near another part of the surface;
the average animal at the centre. Any individual may produce descendants
varying in any direction, but is more likely to produce descendants varying
towards the centre of the sphere, and the variations in that direction will
be greater in amount than the variations towards the surface." This might
be taken as the representation of the normal condition of species (_i.e._
during the periods of repose of the several facets of the spheroids), on
that view which, as before said, may yet be defended.
Judging the organic world from the inorganic, we might expect, _a priori_,
that each species of the former, like crystallized species, would have an
approximate limit of form, and even of size, and at the same time that the
organic, like the inorganic forms, would present modifications in
correspondence with surrounding conditions; but that these modifications
would be, not minute and insignificant, but definite and appreciable,
equivalent to the shifting of the spheroid on to another facet for support.
Mr. Murphy says,[105] "Crystalline formation is also dependent in a very
remarkable way on the medium in which it takes place." "Beudant has found
that common salt crystallizing from pure water forms cubes, but if the
water contains a little boracic acid, the angles of the cubes are
truncated. And the Rev. E. Craig has found that carbonate of copper,
crystallizing from a solution containing sulphuric acid, forms hexagonal
tubular prisms; but if a little ammonia is added, the form changes to that
of a long rectangular prism, with secondary planes in the angles. If a
little more ammonia is added, several varieties of rhombic octahedra
appear; if a little nitric acid is added, the rectangular prism appears
again. The changes take place not by the addition of new crystals, but by
changing the growth of the original ones." These, however, may be said{115}
to be the same species, after all; but recent researches by Dr. H.
Charlton-Bastian seem to show that modifications in the conditions may
result in the evolution of forms so diverse as to constitute different
organic species.
Mr. Murphy observes[106] that "it is scarcely possible to doubt that the
various forms of fungi which are characteristic of particular situations
are not really distinct species, but that the same germ will develop into
different forms, according to the soil on which it falls;" but it is
possible to interpret the facts differently, and it may be that these are
the manifestations of really different and distinct species, developed
according to the different and distinct circumstances in which each is
placed. Mr. Murphy quotes Dr. Carpenter[107] to the effect that "No
_Puccinia_ but the _Puccinia rosæ_ is found upon rose bushes, and this is
seen nowhere else; _Omygena exigua_ is said to be never seen but on the
hoof of a dead horse; and _Isaria felina_ has only been observed upon the
dung of cats, deposited in humid and obscure situations." He adds, "We can
scarcely believe that the air is full of the germs of distinct species of
fungi, of which one never vegetates until it falls on the hoof of a dead
horse, and another till it falls on cat's dung in a damp and dark place."
This is true, but it does not quite follow that they are necessarily the
same species if, as Dr. Bastian seems to show, thoroughly different and
distinct organic forms[108] can be evolved one from another by modifying
the conditions. This observer has brought forward arguments and facts from
which it would appear that such definite, sudden, and considerable
transformations may take place in the lowest organisms. If such is really
the case, we might expect, _a priori_, to find in the highest organisms a
tendency (much more impeded and rare in its manifestations) to {116}
similarly appreciable and sudden changes, under certain stimuli; but a
tendency to continued stability, under normal and ordinary conditions. The
proposition that species have, under ordinary circumstances, a definite
limit to their variability, is largely supported by facts brought forward
by the zealous industry of Mr. Darwin himself. It is unquestionable that
the degrees of variation which have been arrived at in domestic animals
have been obtained more or less readily in a moderate amount of time, but
that further development in certain desired directions is in some a matter
of extreme difficulty, and in others appears to be all but, if not quite,
an impossibility. It is also unquestionable that the degree of divergence
which has been attained in one domestic species is no criterion of the
amount of divergence which has been attained in another. It is contended on
the other side that we have no evidence of any limits to variation other
than those imposed by physical conditions, such, _e.g._, as those which
determine the greatest degree of speed possible to any animal (of a given
size) moving over the earth's surface; also it is said that the differences
in degree of change shown by different domestic animals depend in great
measure upon the abundance or scarcity of individuals subjected to man's
selection, together with the varying direction and amount of his attention
in different cases; finally, it is said that the changes found in nature
are within the limits to which the variation of domestic animals
extends,--it being the case that when changes of a certain amount have
occurred to a species under nature, it becomes _another species_, or
sometimes _two or more other species_ by divergent variations, each of
these species being able again to vary and diverge in any useful direction.
But the fact of the rapidly increasing difficulty found in producing by
ever such careful selection, any further extreme in some charge already
carried very far (such as the tail of the "fan-tailed pigeon" or the crop
of the "pouter"), is certainly, so far as it goes, on the side of the {117}
existence of definite limits to variability. It is asserted in reply, that
physiological conditions of health and life may bar any such further
development. Thus, Mr. Wallace says[109] of these developments: "Variation
seems to have reached its limits in these birds. But so it has in nature.
The fantail has not only more tail-feathers than any of the three hundred
and forty existing species of pigeons, but more than any of the eight
thousand known species of birds. There is, of course, some limit to the
number of feathers of which a tail useful for flight can consist, and in
the fantail we have probably reached that limit. Many birds have the
oesophagus or the skin of the neck more or less dilatable, but in no known
bird is it so dilatable as in the pouter pigeon. Here again the possible
limit, compatible with a healthy existence, has probably been reached. In
like manner, the differences in the size and form of the beak in the
various breeds of the domestic pigeon, is greater than that between the
extreme forms of beak in the various genera and sub-families of the whole
pigeon tribe. From these facts, and many others of the same nature, we may
fairly infer, that if rigid selection were applied to any organ, we could
in a comparatively short time produce a much greater amount of change than
that which occurs between species and species in a state of nature, since
the differences which we do produce are often comparable with those which
exist between distinct genera or distinct families."
But in a domestic bird like the fantail where Natural Selection does not
come into play, the tail-feathers could hardly be limited by "utility for
flight," yet two more tail-feathers could certainly exist in a fancy breed
if "utility for flight" were the only obstacle. It seems probable that the
real barrier is an _internal_ one in the nature of the organism, and the
existence of such is just what is contended for in this chapter. As to{118}
the differences between domestic races being greater than those between
species or even genera, that is not enough for the argument. For upon the
theory of "Natural Selection" all birds have a common origin, from which
they diverged by infinitesimal changes, so that we ought to meet with
sufficient changes to warrant the belief that a hornbill could be produced
from a humming-bird, proportionate time being allowed.
But not only does it appear that there are barriers which oppose change in
certain directions, but that there are positive tendencies to development
along certain special lines. In a bird which has been kept and studied like
the pigeon, it is difficult to believe that any remarkable spontaneous
variations would pass unnoticed by breeders, or that they would fail to be
attended to and developed by some one fancier or other. On the hypothesis
of _indefinite_ variability, it is then hard to say why pigeons with bills
like toucans, or with certain feathers lengthened like those of trogans, or
those of birds of paradise, have never been produced. This, however, is a
question which may be settled by experiment. Let a pigeon be bred with a
bill like a toucan's, and with the two middle tail-feathers lengthened like
those of the king bird of paradise, or even let individuals be produced
which exhibit any marked tendency of the kind, and indefinite variability
shall be at once conceded.
As yet all the changes which have taken place in pigeons are of a few
definite kinds only, such as may be well conceived to be compatible with a
species possessed of a certain inherent capacity for considerable yet
definite variation, a capacity for the ready production of certain degrees
of abnormality, which then cannot be further increased.
Mr. Darwin himself has already acquiesced in the proposition here
maintained, inasmuch as he distinctly affirms the existence of a marked
internal barrier to change in certain cases. And if this is admitted in one
case, the _principle_ is conceded, and it immediately becomes probable that
such internal barriers exist in all, although enclosing a much larger {119}
field for variation in some cases than in others. Mr. Darwin abundantly
demonstrates the variability of dogs, horses, fowls, and pigeons, but he
none the less shows clearly the _very small_ extent to which the goose, the
peacock, and the guinea-fowl have varied.[110] Mr. Darwin attempts to
explain this fact as regards the goose by the animal being valued only for
food and feathers, and from no pleasure having been felt in it on other
accounts. He adds, however, at the end the striking remark,[111] which
concedes the whole position, "but the goose seems to have _a singularly
inflexible organization_." This is not the only place in which such
expressions are used. He elsewhere makes use of phrases which quite
harmonize with the conception of a normal specific constancy, but varying
greatly and suddenly at intervals. Thus he speaks[112] of a _whole
organization seeming to have become plastic, and tending to depart from the
parental type_. That different organisms should have different degrees of
variability, is only what might have been expected _a priori_ from the
existence of parallel differences in inorganic species, some of these
having but a single form, and others being polymorphic.
To return to the goose, however, it may be remarked that it is at least as
probable that its fixity of character is the cause of the neglect, as the
reverse. It is by no means unfair to assume that _had_ the goose shown a
tendency to vary similar in degree to the tendency to variation of the fowl
or pigeon, it would have received attention at once on that account.
As to the peacock it is excused on the pleas (1), that the individuals
maintained are so few in number, and (2) that its beauty is so great it can
hardly be improved. But the individuals maintained _have not been too few_
for the independent origin of the black-shouldered form, or for the
supplanting of the commoner one by it. As to any neglect in selection,{120}
it can hardly be imagined that with regard to this bird (kept as it is all
but exclusively for its beauty), any spontaneous beautiful variation in
colour or form would have been neglected. On the contrary, it would have
been seized upon with avidity and preserved with anxious care. Yet apart
from the black-shouldered and white varieties, no tendency to change has
been known to show itself. As to its being too beautiful for improvement,
that is a proposition which can hardly be maintained. Many consider the
Javan bird as much handsomer than the common peacock, and it would be easy
to suggest a score of improvements as regards either species.
The guinea-fowl is excused, as being "no general favourite, and scarcely
more common than the peacock;" but Mr. Darwin himself shows and admits that
it is a noteworthy instance of constancy under very varied conditions.
These instances alone (and there are yet others) seem sufficient to
establish the assertion, that degree of change is different in different
domestic animals. It is, then, somewhat unwarrantable in any Darwinian to
assume that _all_ wild animals have a capacity for change similar to that
existing in _some_ of the domestic ones. It seems more reasonable to assert
the opposite, namely, that if, as Mr. Darwin says, the capacity for change
is different in different domestic animals, it must surely be limited in
those which have it least, and _a fortiori_ limited in wild animals.
Indeed, it cannot be reasonably maintained that wild species certainly vary
as much as do domestic races; it is possible that they may do so, but at
least this has not been yet shown. Indeed, the much greater degree of
variation amongst domestic animals than amongst wild ones is asserted over
and over again by Mr. Darwin, and his assertions are supported by an
overwhelming mass of facts and instances.
Of course, it may be asserted that a tendency to indefinite change exists
in all cases, and that it is only the circumstances and conditions of {121}
life which modify the effects of this tendency to change so as to produce
such different results in different cases. But assertion is not proof, and
this assertion has not been proved. Indeed, it may be equally asserted (and
the statement is more consonant with some of the facts given), that
domestication in certain animals induces and occasions a capacity for
change which is wanting in wild animals--the introduction of new causes
occasioning new effects. For, though a certain degree of variability
(normally, in all probability, only oscillation) exists in all organisms,
yet domestic ones are exposed to new and different causes of variability,
resulting in such striking divergencies as have been observed. Not even in
this latter case, however, is it necessary to believe that the variability
is indefinite, but only that the small oscillations become in certain
instances intensified into large and conspicuous ones. Moreover, it is
possible that some of our domestic animals have been in part chosen and
domesticated through possessing variability in an eminent degree.
That each species exhibits certain oscillations of structure is admitted on
all hands. Mr. Darwin asserts that this is the exhibition of a tendency to
vary which is absolutely indefinite. If this indefinite variability _does_
exist, of course no more need be said. But we have seen that there are
arguments _a priori_ and _a posteriori_ against it, while the occurrence of
variations in certain domestic animals greater in degree than the
differences between many wild species, is no argument in favour of its
existence, until it can be shown that the causes of variability in the one
case are the same as in the other. An argument against it, however, may be
drawn from the fact, that certain animals, though placed under the
influence of those exceptional causes of variation to which domestic
animals are subject, have yet never been known to vary, even in a degree
equal to that in which certain wild kinds have been ascertained to vary.
In addition to this immutability of character in some animals, it is {122}
undeniable, that domestic varieties have little stability, and much
tendency to reversion, whatever be the true explanation of such phenomena.
In controverting the generally received opinion as to "reversion," Mr.
Darwin has shown that it is not all breeds which in a few years revert to
the original form; but he has shown no more. Thus, the feral rabbits of
Porto Santo, Jamaica, and the Falkland Islands, have not yet so reverted in
those several localities.[113] Nevertheless, a Porto Santo rabbit brought
to England reverted in a manner the most striking, recovering the proper
colour of its fur "in rather less than four years."[114] Again, the white
silk fowl, in our climate, "reverts to the ordinary colour of the common
fowl in its skin and bones, due care having been taken to prevent any
cross."[115] This reversion taking place in spite of careful selection, is
very remarkable.
Numerous other instances of reversion are given by Mr. Darwin, both as
regards plants and animals; amongst others, the singular fact of bud
reversion.[116] The curiously recurring development of black sheep, in
spite of the most careful breeding, may also be mentioned, though, perhaps,
reversion has no part in the phenomenon.
These facts seem certainly to tell in favour of limited variability, while
the cases of non-reversion do not contradict it, as it is not contended
that all species have the same tendency to revert, but rather that their
capacities in this respect, as well as for change, are different in
different kinds, so that often reversion may only show itself at the end of
very long periods indeed.
Yet some of the instances given as probable or possible causes of reversion
by Mr. Darwin, can hardly be such. He cites, for example, the occasional
presence of supernumerary digits in man.[117] For this notion, however, he
is not responsible, as he rests his remark on the authority of a {123}
passage published by Professor Owen. Again, he refers[118] to "the greater
frequency of a monster proboscis in the pig than in any other animal." But
with the exception of the peculiar muzzle of the Saiga (or European
antelope), the only known proboscidian Ungulates are the elephants and
tapirs, and to neither of these has the pig any close affinity. It is
rather in the horse than in the pig that we might look for the appearance
of a reversionary proboscis, as both the elephants and the tapirs have the
toes of the hind foot of an odd number. It is true that the elephants are
generally considered to form a group apart from both the odd and the
even-toed Ungulata. But of the two, their affinities with the odd-toed
division are more marked.[119]
Another argument in favour of the, at least intermitting, constancy of
specific forms and of sudden modification, may be drawn from the absence of
minute transitional forms, but this will be considered in the next chapter.
It remains now to notice in favour of specific stability, that the
objection drawn from physiological difference between "species" and "races"
still exists unrefuted.
Mr. Darwin freely admits difficulties regarding the sterility of different
species when crossed, and shows satisfactorily that it could never have
arisen from the action of "Natural Selection." He remarks[120] also: "With
some few exceptions, in the case of plants, domesticated varieties, such as
those of the dog, fowl, pigeon, several fruit trees, and culinary
vegetables, which differ from each other in external characters more than
many species, are perfectly fertile when crossed, or even fertile in {124}
excess, whilst closely allied species are almost invariably in some degree
sterile."
Again, after speaking of "the general law of good being, derived from the
intercrossing of distinct individuals of the same species," and the
evidence that the pollen of a distinct _variety_ or race is prepotent over
a flower's own pollen, adds the very significant remark,[121] "When
distinct _species_ are crossed, the case is directly the reverse, for a
plant's own pollen is almost always prepotent over foreign pollen."
Again he adds:[122] "I believe from observations communicated to me by Mr.
Hewitt, who has had great experience in hybridizing pheasants and fowls,
that the early death of the embryo is a very frequent cause of sterility in
first crosses. Mr. Salter has recently given the results of an examination
of about 500 eggs produced from various crosses between three species of
Gallus and their hybrids. The majority of these eggs had been fertilized,
and in the majority of the fertilized eggs the embryos either had been
partially developed and had then aborted, or had become nearly mature, but
the young chickens had been unable to break through the shell. Of the
chickens which were born, more than four-fifths died within the first few
days, or at latest weeks, 'without any obvious cause, apparently from mere
inability to live,' so that from 500 eggs only twelve chickens were reared.
The early death of hybrid embryos probably occurs in like manner with
plants, at least it is known that hybrids raised from very distinct species
are sometimes weak and dwarfed, and perish at an early age, of which fact
Max Wichura has recently given some striking cases with hybrid willows."
Mr. Darwin objects to the notion that there is any special sterility
imposed to check specific intermixture and change, saying,[123] "To grant
to species the special power of producing hybrids, and then to stop {125}
their further propagation by different degrees of sterility, not strictly
related to the facility of the first union between their parents, seems a
strange arrangement."
But this only amounts to saying that the author himself would not have so
acted had he been the Creator. A "strange arrangement" must be admitted
anyhow, and all who acknowledge teleology at all, must admit that the
strange arrangement was designed. Mr. Darwin says, as to the sterility of
species, that the cause lies exclusively in their sexual constitution; but
all that need be affirmed is that sterility is brought about somehow, and
it is undeniable that "crossing" _is_ checked. All that is contended for is
that there _is_ a bar to the intermixture of _species_, but not of
_breeds_; and if the conditions of the generative products are that bar, it
is enough for the argument, no special kind of barring action being
contended for.
He, however, attempts to account for the modification of the sexual
products of species as compared with those of varieties, by the exposure of
the former to more uniform conditions during longer periods of time than
those to which varieties are exposed, and that as wild animals, when
captured, are often rendered sterile by captivity, so the influence of
union with another species may produce a similar effect. It seems to the
author an unwarrantable assumption that a cross with what, on the Darwinian
theory, can only be a slightly diverging descendant of a common parent,
should produce an effect equal to that of captivity, and consequent change
of habit, as well as considerable modification of food.
No clear case has been given by Mr. Darwin in which mongrel animals,
descended from the same undoubted species, have been persistently infertile
_inter se_; nor any clear case in which hybrids between animals, generally
admitted to be distinct species, have been continuously fertile _inter se_.
It is true that facts are brought forward tending to establish the
probability of the doctrine of Pallas, that species may sometimes be {126}
rendered fertile by domestication. But even if this were true, it would be
no approximation towards proving the converse, _i.e._ that races and
varieties may become sterile when wild. And whatever may be the preference
occasionally shown by certain breeds to mate with their own variety, no
sterility is recorded as resulting from unions with other varieties.
Indeed, Mr. Darwin remarks,[124] "With respect to sterility from the
crossing of domestic races, I know of no well-ascertained case with
animals. This fact (seeing the great difference in structure between some
breeds of pigeons, fowls, pigs, dogs, &c.) is extraordinary when contrasted
with the sterility, of many closely-allied natural species when crossed."
It has been alleged that the domestic and wild guinea-pig do not breed
together, but the specific identity of these forms is very problematical.
Mr. A. D. Bartlett, superintendent of the Zoological Gardens, whose
experience is so great, and observation so quick, believes them to be
decidedly distinct species.
Thus, then, it seems that a certain normal specific stability in species,
accompanied by occasional sudden and considerable modifications, might be
expected _a priori_ from what we know of crystalline inorganic forms and
from what we may anticipate with regard to the lowest organic ones. This
presumption is strengthened by the knowledge of the increasing difficulties
which beset any attempt to indefinitely intensify any race characteristics.
The obstacles to this indefinite intensification, as well as to certain
lines of variation in certain cases, appear to be not only external, but to
depend on internal causes or an internal cause. We have seen that Mr.
Darwin himself implicitly admits the principle of specific stability in
asserting the singular inflexibility of the organization of the goose. We
have also seen that it is not fair to conclude that all wild races can vary
as much as the most variable domestic ones. It has also been shown {127}
that there are grounds for believing in a tendency to reversion generally,
as it is distinctly present in certain instances. Also that specific
stability is confirmed by the physiological obstacles which oppose
themselves to any considerable or continued intermixture of species, while
no such barriers oppose themselves to the blending of varieties. All these
considerations taken together may fairly be considered as strengthening the
belief that specific manifestations are relatively stable. At the same time
the view advocated in this book does not depend upon, and is not identified
with, any such stability. All that the Author contends for is that specific
manifestation takes place along certain lines, and according to law, and
not in an exceedingly minute, indefinite, and fortuitous manner. Finally,
he cannot but feel justified, from all that has been brought forward, in
reiterating the opening assertion of this chapter that something is still
to be said for the view which maintains that species are stable, at least
in the intervals of their comparatively rapid successive {128}
manifestations.
* * * * *
CHAPTER VI.
SPECIES AND TIME.
Two relations of species to time.--No evidence of past existence of
minutely intermediate forms when such might be expected _a
priori_.--Bats, Pterodactyles, Dinosauria, and Birds.--Ichthyosauria,
Chelonia, and Anoura.--Horse ancestry.--Labyrinthodonts and
Trilobites.--Two subdivisions of the second relation of species to
time.--Sir William Thomson's views.---Probable period required for
ultimate specific evolution from primitive ancestral
forms.--Geometrical increase of time required for rapidly multiplying
increase of structural differences.--Proboscis monkey.--Time required
for deposition of strata necessary for Darwinian evolution.--High
organization of Silurian forms of life.--Absence of fossils in oldest
rocks.--Summary and conclusion.
Two considerations present themselves with regard to the necessary relation
of species to time if the theory of "Natural Selection" is valid and
sufficient.
The first is with regard to the evidences of the past existence of
intermediate form, their duration and succession.
The second is with regard to the total amount of time required for the
evolution of all organic forms from a few original ones, and the bearing of
other sciences on this question of time.
As to the first consideration, evidence is as yet against the modification
of species by "Natural Selection" alone, because not only are minutely
transitional forms generally absent, but they are absent in cases where we
might certainly _a priori_ have expected them to be present. [Page 129]
Now it has been said:[125] "If Mr. Darwin's theory be true, the number of
varieties differing one from another a very little must have been
indefinitely great, so great indeed as probably far to exceed the number of
individuals which have existed of any one variety. If this be true, it
would be more probable that no two specimens preserved as fossils should be
of one variety than that we should find a great many specimens collected
from a very few varieties, provided, of course, the chances of preservation
are equal for all individuals." "It is really strange that vast numbers of
perfectly similar specimens should be found, the chances against their
perpetuation as fossils are so great; but it is also very strange that the
specimens should be so exactly alike as they are, if, in fact, they came
and vanished by a gradual change."
Mr. Darwin attempts[126] to show cause why we should believe _a priori_
that intermediate varieties would exist in lesser numbers than the more
extreme forms; but though they would doubtless do so sometimes, it seems
too much to assert that they would do so generally, still less universally.
Now little less than universal and very marked inferiority in numbers would
account for the absence of certain series of minutely intermediate fossil
specimens. The mass of palæontological evidence is indeed overwhelmingly
against minute and gradual modification. It is true that when once an
animal has obtained powers of flight its means of diffusion are
indefinitely increased, and we might expect to find many relics of an
aërial form and few of its antecedent state--with nascent wings just
commencing their suspensory power. Yet had such a slow mode of origin, as
Darwinians contend for, operated exclusively in all cases, it is absolutely
incredible that birds, bats, and pterodactyles should have left the remains
they have, and yet not a single relic be preserved in any one instance{130}
of any of these different forms of wing in their incipient and relatively
imperfect functional condition!
[Illustration: WING-BONES OF PTERODACTYLE, BAT, AND BIRD.]
Whenever the remains of bats have been found they have presented the exact
type of existing forms, and there is as yet no indication of the conditions
of an incipient elevation from the ground.
The pterodactyles, again, though a numerous group, are all true and perfect
pterodactyles, though surely _some_ of the many incipient forms, which on
the Darwinian theory have existed, must have had a good chance of
preservation.
As to birds, the only notable instance in which discoveries recently made
appear to fill up an important hiatus, is the interpretation given by
Professor Huxley[127] to the remains of Dinosaurian reptiles, and which
were noticed in the third chapter of this work. The learned Professor has
(as also has Professor Cope in America) shown that in very important {131}
and significant points the skeletons of the Iguanodon and of its allies
approach very closely to that existing in the ostrich, emeu, rhea, &c. He
has given weighty reasons for thinking that the line of affinity between
birds and reptiles passes to the birds last named from the Dinosauria
rather than from the Pterodactyles, through Archeopteryx-like forms to the
ordinary birds. Finally, he has thrown out the suggestion that the
celebrated footsteps left by some extinct three-toed creatures on the very
ancient sandstone of Connecticut were made, not, as hitherto supposed, by
true birds, but by more or less ornithic reptiles. But even supposing all
that is asserted or inferred on this subject to be fully proved, it would
not approach to a demonstration of specific origin by _minute_
modification. And though it harmonizes well with "Natural Selection," it is
equally consistent with the rapid and sudden development of new specific
forms of life. Indeed, Professor Huxley, with a laudable caution and
moderation too little observed by some Teutonic Darwinians, guarded himself
carefully from any imputation of asserting dogmatically the theory of
"Natural Selection," while upholding fully the doctrine of evolution.
But, after all, it is by no means certain, though very probable, that the
Connecticut footsteps were made by very ornithic reptiles, or extremely
sauroid birds. And it must not be forgotten that a completely carinate[128]
bird (the Archeopteryx) existed at a time, when, as yet, we have no
evidence of some of the Dinosauria having come into being. Moreover, if the
remarkable and minute similarity of the coracoid of a pterodactyle to that
of a bird be merely the result of function and no sign of genetic affinity,
it is not inconceivable that pelvic and leg resemblances of Dinosauria to
birds may be functional likewise, though such an explanation is, of {132}
course, by no means necessary to support the view maintained in this book.
[Illustration: THE ARCHEOPTERYX (OF THE OOLITE STRATA).]
[Illustration: SKELETON OF AN ICHTHYOSAURUS.]
But the number of forms represented by many individuals, yet by _no
transitional ones_, is so great that only two or three can be selected as
examples. Thus those remarkable fossil reptiles, the Ichthyosauria and
Plesiosauria, extended, through the secondary period, probably over the
greater part of the globe. Yet no single transitional form has yet been met
with in spite of the multitudinous individuals preserved. Again, with their
modern representatives the Cetacea, one or two aberrant forms alone {133}
have been found, but no series of transitional ones indicating minutely the
line of descent. This group, the whales, is a very marked one, and it is
curious, on Darwinian principles, that so few instances tending to indicate
its mode of origin should have presented themselves. Here, as in the bats,
we might surely expect that some relics of unquestionably incipient stages
of its development would have been left.
[Illustration: SKELETON OF A PLESIOSAURUS.]
The singular order Chelonia, including the tortoises, turtles, and
terrapins (or fresh-water tortoises), is another instance of an extreme
form without any, as yet known, transitional stages. Another group may be
finally mentioned, viz. the frogs and toads, anourous Batrachians, of which
we have at present no relic of any kind linking them on to the Eft group on
the one hand, or to reptiles on the other.
The only instance in which an approach towards a series of nearly related
forms has been obtained is the existing horse, its predecessor Hipparion
and other extinct forms. But even here there is no proof whatever of
modification by minute and infinitesimal steps; _a fortiori_ no approach to
a proof of modification by "Natural Selection," acting upon indefinite
fortuitous variations. On the contrary, the series is an admirable example
of successive modification in one special direction along one beneficial
line, and the teleologist must here be allowed to consider that one {134}
motive of this modification (among probably an indefinite number of motives
inconceivable to us) was the relationship in which the horse was to stand
to the human inhabitants of this planet. These extinct forms, as Professor
Owen, remarks,[129] "differ from each other in a greater degree than do the
horse, zebra, and ass," which are not only good _zoological_ species as to
form, but are species _physiologically_, _i.e._ they cannot produce a race
of hybrids fertile _inter se_.
As to the mere action of surrounding conditions, the same Professor
remarks:[130] "Any modification affecting the density of the soil might so
far relate to the changes of limb-structure, as that a foot with a pair of
small hoofs dangling by the sides of the large one, like those behind the
cloven hoof of the ox, would cause the foot of Hipparion, _e.g._, and _a
fortiori_ the broader based three-hoofed foot of the Palæothere, to sink
less deeply into swampy soil, and be more easily withdrawn than the more
concentratively simplified and specialized foot of the horse. Rhinoceroses
and zebras, however, tread together the arid plains of Africa in the
present day; and the horse has multiplied in that half of America where two
or more kinds of tapir still exist. That the continents of the Eocene or
Miocene periods were less diversified in respect of swamp and sward, pampas
or desert, than those of the Pliocene period, has no support from
observation or analogy."
Not only, however, do we fail to find any traces of the incipient stages of
numerous very peculiar groups of animals, but it is undeniable that there
are instances which appeared at first to indicate a _gradual transition_,
yet which instances have been shown by further investigation and discovery
not to indicate truly anything of the kind. Thus at one time the remains of
Labyrinthodonts, which up till then had been discovered, seemed to justify
the opinion that as time went on, forms had successively appeared with{135}
more and more complete segmentation and ossification of the backbone, which
in the earliest forms was (as it is in the lowest fishes now) a soft
continuous rod or notochord. Now, however, it is considered probable that
the soft back-boned Labyrinthodont Archegosaurus, was an immature or larval
form,[131] while Labyrinthodonts with completely developed vertebræ have
been found to exist amongst the very earliest forms yet discovered. The
same may be said regarding the eyes of the trilobites, some of the oldest
forms having been found as well furnished in that respect as the very last
of the group which has left its remains accessible to observation.
[Illustration: TRILOBITE.]
Such instances, however, as well as the way in which marked and special
forms (as the Pterodactyles, &c., before referred to) appear at once in and
similarly disappear from the geological record, are of course explicable on
the Darwinian theory, provided a sufficiently enormous amount of past time
be allowed. The alleged extreme, and probably great, imperfection of that
record may indeed be pleaded in excuse. But it _is_ an excuse.[132] {136}
Nor is it possible to deny the _a priori_ probability of the preservation
of at least a few _minutely transitional_ forms in some instances if
_every_ species without exception has arisen exclusively by such minute and
gradual transitions.
It remains, then, to turn to the other considerations with regard to the
relation of species to time: namely (1) as to the total amount of time
allowable by other sciences for organic evolution; and (2) the proportion
existing, on Darwinian principles, between the time anterior to the earlier
fossils, and the time since; as evidenced by the proportion between the
amount of evolutionary change during the latter epoch and that which must
have occurred anteriorly.
Sir William Thomson has lately[133] advanced arguments from three distinct
lines of inquiry, and agreeing in one approximate result. The three lines
of inquiry were--1. The action of the tides upon the earth's rotation. 2.
The probable length of time during which the sun has illuminated this
planet; and 3. The temperature of the interior of the earth. The result
arrived at by these investigations is a conclusion that the existing state
of things on the earth, life on the earth, all geological history showing
continuity of life, must be limited within some such period of past time as
one hundred million years. The first question which suggests itself,
supposing Sir W. Thomson's views to be correct, is, Is this period anything
like enough for the evolution of all organic forms by "Natural Selection"?
The second is, Is this period anything like enough for the deposition of
the strata which must have been deposited if all organic forms have been
evolved by _minute_ steps, according to the Darwinian theory?
In the first place, as to Sir William Thomson's views, the Author of this
book cannot presume to advance any opinion; but the fact that they have not
been refuted, pleads strongly in their favour when we consider how {137}
much they tell against the theory of Mr. Darwin. The last-named author only
remarks that "many of the elements in the calculation are more or less
doubtful,"[134] and Professor Huxley[135] does not attempt to _refute_ Sir
W. Thomson's arguments, but only to show cause for suspense of judgment,
inasmuch as the facts _may be_ capable of other explanations.
Mr. Wallace, on the other hand,[136] seems more disposed to accept them,
and, after considering Sir William's objections and those of Mr. Croll,
puts the probable date of the beginning of the Cambrian deposits[137] at
only twenty-four million years ago. On the other hand, he seems to consider
that specific change has been more rapid than generally supposed, and
exceptionally stable during the last score or so of thousand years.
Now, first, with regard to the time required for the evolution of all
organic forms by merely accidental, minute, and fortuitous variations, the
useful ones of which have been preserved:
Mr. Murphy[138] is distinctly of opinion that there has not been time
enough. He says, "I am inclined to think that geological time is too short
for the evolution of the higher forms of life out of the lower by that
accumulation of imperceptibly slow variations, to which alone Darwin
ascribes the whole process."
"Darwin justly mentions the greyhound as being equal to any natural species
in the perfect co-ordination of its parts, 'all adapted for extreme
fleetness and for running down weak prey.'" "Yet it is an artificial
species (and not _physiologically_ a species _at all_), formed by
long-continued selection under domestication; and there is no reason to
suppose that any of the variations which have been selected to form it have
been other than gradual and almost imperceptible. Suppose that it has {138}
taken five hundred years to form the greyhound out of his wolf-like
ancestor. This is a mere guess, but it gives the order of the magnitude."
Now, if so, "how long would it take to obtain an elephant from a protozoon,
or even from a tadpole-like fish? Ought it not to take much more than a
million times as long?"[139]
Mr. Darwin[140] would compare with the natural origin of a species
"unconscious selection, that is, the preservation of the most useful or
beautiful animals, with no intention of modifying the breed." He adds: "But
by this process of unconscious selection, various breeds have been sensibly
changed in the course of two or three centuries."
"Sensibly changed!" but not formed into "new species." Mr. Darwin, of
course, could not mean that species _generally_ change so rapidly, which
would be strangely at variance with the abundant evidence we have of the
stability of animal forms as represented on Egyptian monuments and as shown
by recent deposits. Indeed, he goes on to say,--"Species, however, probably
change much more slowly, and within the same country only a few change at
the same time. This slowness follows from all the inhabitants of the same
country being already so well adapted to each other, that places in the
polity of nature do not occur until after long intervals, when changes of
some kind in the physical conditions, or through immigration, have
occurred, and individual differences and variations of the right nature, by
which some of the inhabitants might be better fitted to their new places
under altered circumstances, might not at once occur." This is true, and
not only will these changes occur at distant intervals, but it must be
borne in mind that in tracing back an animal to a remote ancestry, we pass
through modifications of such rapidly increasing number and importance that
a geometrical progression can alone indicate the increase of periods {139}
which such profound alterations would require for their evolution through
"Natural Selection" only.
Thus let us take for an example the proboscis monkey of Borneo
(_Semnopithecus nasalis_). According to Mr. Darwin's own opinion, this form
might have been "sensibly changed" in the course of two or three centuries.
According to this, to evolve it as a true and perfect species one thousand
years would be a very moderate period. Let ten thousand years be taken to
represent approximately the period of substantially constant conditions
during which no considerable change would be brought about. Now, if one
thousand years may represent the period required for the evolution of the
species _S. nasalis_, and of the other species of the genus Semnopithecus;
ten times that period should, I think, be allowed for the differentiation
of that genus, the African Cercopithecus and the other genera of the family
Simiidæ--the differences between the genera being certainly more than
tenfold greater than those between the species of the same genus. Again we
may perhaps interpose a period of ten thousand years' comparative repose.
For the differentiation of the families Simiidæ and Cebidæ--so very much
more distinct and different than any two genera of either family--a period
ten times greater should, I believe, be allowed than that required for the
evolution of the subordinate groups. A similarly increasing ratio should be
granted for the successive developments of the difference between the
Lemuroid and the higher forms of primates; for those between the original
primate and other root-forms of placental mammals; for those between
primary placental and implacental mammals, and perhaps also for the
divergence of the most ancient stock of these and of the monotremes, for in
all these cases modifications of structure appear to increase in complexity
in at least that ratio. Finally, a vast period must be granted for the
development of the lowest mammalian type from the primitive stock of the
whole vertebrate sub-kingdom. Supposing this primitive stock to have {140}
arisen directly from a very lowly organized animal indeed (such as a
nematoid worm, or an ascidian, or a jelly-fish), yet it is not easy to
believe that less than two thousand million years would be required for the
totality of animal development by no other means than minute, fortuitous,
occasional, and intermitting variations in all conceivable directions. If
this be even an approximation to the truth, then there seem to be strong
reasons for believing that geological time is not sufficient for such a
process.
The second question is, whether there has been time enough for the
deposition of the strata which must have been deposited, if all organic
forms have been evolved according to the Darwinian theory?
Now this may at first seem a question for geologists only, but, in fact, in
this matter geology must in some respects rather take its time from zoology
than the reverse; for if Mr. Darwin's theory be true, past time down to the
deposition of the Upper Silurian strata can have been but a very small
fraction of that during which strata have been deposited. For when those
Upper Silurian strata were formed, organic evolution had already run a
great part of its course, perhaps the longest, slowest, and most difficult
part of that course.
At that ancient epoch not only were the vertebrate, molluscous, and
arthropod types distinctly and clearly differentiated, but highly developed
forms had been produced in each of these sub-kingdoms. Thus in the
Vertebrata there were fishes not belonging to the lowest but to the very
highest groups which are known to have ever been developed, namely, the
Elasmobranchs (the highly organized sharks and rays) and the Ganoids, a
group now poorly represented, but for which the sturgeon may stand as a
type, and which in many important respects more nearly resemble higher
Vertebrata than do the ordinary or osseous fishes. Fishes in which the
ventral fins are placed in front of the pectoral ones (_i.e._ jugular
fishes) have been generally considered to be comparatively modern forms.
But Professor Huxley has kindly informed me that he has discovered a {141}
jugular fish in the Permian deposits.
Amongst the molluscous animals we have members of the very highest known
class, namely, the Cephalopods, or cuttle-fish class; and amongst
articulated animals we find Trilobites and Eurypterida, which do not belong
to any incipient worm-like group, but are distinctly differentiated
Crustacea of no low form.
[Illustration: CUTTLE-FISH.
A. Ventral aspect. B. Dorsal aspect.]
We have in all these animal types nervous systems differentiated on
distinctly different patterns, fully formed organs of circulation,
digestion, excretion, and generation, complexly constructed eyes and other
sense organs; in fact, all the most elaborate and complete animal
structures built up, and not only once, for in the fishes and mollusca we
have (as described in the third chapter of this work) the coincidence of
the independently developed organs of sense attaining a nearly similar
complexity in two quite distinct forms. If, then, so small an advance {142}
has been made in fishes, molluscs, and arthropods since the Upper Silurian
deposits, it will probably be within the mark to consider that the period
before those deposits (during which all these organs would, on the
Darwinian theory, have slowly built up their different perfections and
complexities) occupied time at least a hundredfold greater.
Now it will be a moderate computation to allow 25,000,000 years for the
deposition of the strata down to and including the Upper Silurian. If,
then, the evolutionary work done during this deposition, only represents a
hundredth part of the sum total, we shall require 2,500,000,000 (two
thousand five hundred million) years for the complete development of the
whole animal kingdom to its present state. Even one quarter of this,
however, would far exceed the time which physics and astronomy seem able to
allow for the completion of the process.
Finally, a difficulty exists as to the reason of the absence of rich
fossiliferous deposits in the oldest strata--if life was then as abundant
and varied as, on the Darwinian theory, it must have been. Mr. Darwin
himself admits[141] "the case at present must remain inexplicable; and may
be truly urged as a valid argument against the views" entertained in his
book.
Thus, then, we find a wonderful (and on Darwinian principles an all but
inexplicable) absence of minutely transitional forms. All the most marked
groups, bats, pterodactyles, chelonians, ichthyosauria, anoura, &c., appear
at once upon the scene. Even the horse, the animal whose pedigree has been
probably best preserved, affords no conclusive evidence of specific origin
by infinitesimal, fortuitous variations; while some forms, as the
labyrinthodonts and trilobites, which seemed to exhibit gradual change, are
shown by further investigation to do nothing of the sort. As regards the
time required for evolution (whether estimated by the probably minimum{143}
period required for organic change or for the deposition of strata which
accompanied that change), reasons have been suggested why it is likely that
the past history of the earth does not supply us with enough. First,
because of the prodigious increase in the importance and number of
differences and modifications which we meet with as we traverse
successively greater and more primary zoological groups; and, secondly,
because of the vast series of strata necessarily deposited if the period
since the Lower Silurian marks but a small fraction of the period of
organic evolution. Finally, the absence or rarity of fossils in the oldest
rocks is a point at present inexplicable, and not to be forgotten or
neglected.
Now all these difficulties are avoided if we admit that new forms of animal
life of all degrees of complexity appear from time to time with comparative
suddenness, being evolved according to laws in part depending on
surrounding conditions, in part internal--similar to the way in which
crystals (and, perhaps from recent researches, the lowest forms of life)
build themselves up according to the internal laws of their component
substance, and in harmony and correspondence with all environing influences
and conditions. [Page 144]
* * * * *
CHAPTER VII.
SPECIES AND SPACE.
The geographical distribution of animals presents difficulties.--These
not insurmountable in themselves; harmonize with other
difficulties.--Fresh-water fishes.--Forms common to Africa and India;
to Africa and South America; to China and Australia; to North America
and China; to New Zealand and South America; to South America and
Tasmania; to South America and Australia.--Pleurodont
lizards.--Insectivorous mammals.--Similarity of European and South
American frogs--Analogy between European salmon and fishes of New
Zealand, &c. An ancient Antarctic continent probable.--Other modes of
accounting for facts of distribution.--Independent origin of closely
similar forms.--Conclusion.
The study of the distribution of animals over the earth's surface presents
us with many facts having certain not unimportant bearings on the question
of specific origin. Amongst these are instances which, at least at first
sight, appear to conflict with the Darwinian theory of "Natural Selection."
It is not, however, here contended that such facts do by any means
constitute by themselves obstacles which cannot be got over. Indeed it
would be difficult to imagine any obstacles of the kind which could not be
surmounted by an indefinite number of terrestrial modifications of
surface--submergences and emergences--junctions and separations of
continents in all directions and combinations of any desired degree of
frequency. All this being supplemented by the intercalation of armies of
enemies, multitudes of ancestors of all kinds, and myriads of connecting
forms, whose _raison d'être_ may be simply their utility or necessity {145}
for the support of the theory of "Natural Selection."
Nevertheless, when brought in merely to supplement and accentuate
considerations and arguments derived from other sources, in that case
difficulties connected with the geographical distribution of animals are
not without significance, and are worthy of mention even though, by
themselves, they constitute but feeble and more or less easily explicable
puzzles which could not alone suffice either to sustain or to defeat any
theory of specific origination.
Many facts as to the present distribution of animal life over the world are
very readily explicable by the hypothesis of slight elevations and
depressions of larger and smaller parts of its surface, but there are
others the existence of which it is much more difficult so to explain.
The distribution either of animals possessing the power of flight, or of
inhabitants of the ocean, is, of course, easily to be accounted for; the
difficulty, if there is really any, must mainly be with strictly
terrestrial animals of moderate or small powers of locomotion and with
inhabitants of fresh water. Mr. Darwin himself observes,[142] "In regard to
fish, I believe that the same species never occur in the fresh waters of
distant continents." Now, the Author is enabled, by the labours and through
the kindness of Dr. Günther, to show that this belief cannot be maintained;
he having been so obliging as to call attention to the following facts with
regard to fish-distribution. These facts show that though only one species
which is absolutely and exclusively an inhabitant of fresh water is as yet
known to be found in distant continents, yet that in several other
instances the same species _is_ found in the fresh water of distant
continents, and that very often the same _genus_ is so distributed.
The genus _Mastacembelus_ belongs to a family of fresh-water Indian {146}
fishes. Eight species of this genus are described by Dr. Günther in his
catalogue.[143] These forms extend from Java and Borneo on the one hand, to
Aleppo on the other. Nevertheless, a new species (_M. cryptacanthus_) has
been described by the same author,[144] which is an inhabitant of the
Camaroon country of _Western_ Africa. He observes, "The occurrence of
Indian forms on the West Coast of Africa, such as _Periophthalmus_,
_Psettus_, _Mastacembelus_, is of the highest interest, and an almost new
fact in our knowledge of the geographical distribution of fishes."
_Ophiocephalus_, again, is a truly Indian genus, there being no less than
twenty-five species,[145] all from the fresh waters of the East Indies. Yet
Dr. Günther informs me that there is a species in the Upper Nile and in
West Africa.
The acanthopterygian family (_Labyrinthici_) contains nine freshwater
genera, and these are distributed between the East Indies and South and
Central Africa.
The Carp fishes (Cyprinoids) are found in India, Africa, and Madagascar,
but there are none in South America.
Thus existing fresh-water fishes point to an immediate connexion between
Africa and India, harmonizing with what we learn from Miocene mammalian
remains.
On the other hand, the Characinidæ (a family of the physostomous fishes)
are found in Africa and South America, and not in India, and even its
component groups are so distributed,--namely, the _Tetragonopterina_[146]
and the _Hydrocyonina_.[147]
Again, we have similar phenomena in that almost exclusively fresh-water
group the Siluroids.
Thus the genera _Clarias_[148] and _Heterobranchus_[149] are found {147}
both in Africa and the East Indies. _Plotosus_ is found in Africa, India,
and Australia, and the species _P. anguillaris_[150] has been brought from
both China and Moreton Bay. Here, therefore, we have the same species in
two distinct geographical regions. It is however a coast fish, which,
though entering rivers, yet lives in the sea.
_Eutropius_[151] is an African genus, but _E. obtusirostris_ comes from
India. On the other hand, _Amiurus_ is a North American form; but one
species, _A. cantonensis_,[152] comes from China.
The genus _Galaxias_[153] has at least one species common to New Zealand
and South America, and one common to South America and Tasmania. In this
genus we thus have an absolutely and completely fresh-water form _of the
very same species_ distributed between different and distinct geographical
regions.
Of the lower fishes, a lamprey, _Mordacia mordax_,[154] is common to South
Australia and Chile; while another form of the same family, namely,
_Geotria chilensis_,[155] is found not only in South America and Australia,
but in New Zealand also. These fishes, however, probably pass part of their
lives in the sea.
We thus certainly have several species which _are_ common to the fresh
waters of distant continents, although it cannot be certainly affirmed that
they are exclusively and entirely fresh-water fishes throughout all their
lives except in the case of _Galaxias_.
Existing forms point to a close union between South America and Africa on
the one hand, and between South America, Australia, Tasmania, and New
Zealand on the other; but these unions were not synchronous any more than
the unions indicated between India and Australia, China and Australia,
China and North America, and India and Africa.
Pleurodont lizards are such as have the teeth attached by their sides {148}
to the inner surface of the jaw, in contradistinction to acrodont lizards,
which have the bases of their teeth anchylosed to the summit of the margin
of the jaw. Now pleurodont iguanian lizards abound in the South American
region; but nowhere else, and are not as yet known to inhabit any part of
the present continent of Africa. Yet pleurodont lizards, strange to say,
are found in Madagascar. This is the more remarkable, inasmuch as we have
no evidence yet of the existence in Madagascar of fresh-water fishes common
to Africa and South America.
[Illustration: INNER SIDE OF LOWER JAW OF PLEURODONT LIZARD.
(Showing the teeth attached to the inner surface of its side.)]
Again, that remarkable island Madagascar is the home of very singular and
special insectivorous beasts of the genera Centetes, Ericulus, and
Echinops; while the only other member of the group to which they belong is
Solenodon, which is a resident in the West Indian Islands, Cuba and Hayti.
The connexion, however, between the West Indies and Madagascar must surely
have been at a time when the great lemurine group was absent; for it is
difficult to understand the spread of such a form as Solenodon, and at the
same time the non-extension of the active lemurs, or their utter
extirpation, in such a congenial locality as the West Indian Archipelago.
The close connexion of South America and Australia is demonstrated (on the
Darwinian theory), not only from the marsupial fauna of both, but also from
the frogs and toads which respectively inhabit those regions. A truly
remarkable similarity and parallelism exist, however, between certain of
the same animals inhabiting South Western America and Europe. Thus Dr.{149}
Günther has described[156] a frog from Chile by the name of cacotus, which
singularly resembles the European bombinator.
[Illustration: SOLENODON.]
Again of the salmons, two genera from South America, New Zealand, and
Australia, are analogous to European salmons.
In addition to this may be mentioned a quotation from Professor Dana, given
by Mr. Darwin,[157] to the effect that "it is certainly a wonderful fact
that New Zealand should have a closer resemblance in its crustacea to Great
Britain, its antipode, than to any other part of the world:" and Mr. Darwin
adds "Sir J. Richardson also speaks of the reappearance on the shores of
New Zealand, Tasmania, &c. of northern forms of fish. Dr. Hooker informs me
that twenty-five species of algæ are common to New Zealand and to {150}
Europe, but have not been found in the intermediate tropical seas."
Many more examples of the kind could easily be brought, but these must
suffice. As to the last-mentioned cases Mr. Darwin explains them by the
influence of the glacial epoch, which he would extend actually across the
equator, and thus account, amongst other things, for the appearance in
Chile of frogs having close genetic relations with European forms. But it
is difficult to understand the persistence and preservation of such
exceptional forms with the extirpation of all the others which probably
accompanied them, if so great a migration of northern kinds had been
occasioned by the glacial epoch.
Mr. Darwin candidly says,[158] "I am far from supposing that all
difficulties in regard to the distribution and affinities of the identical
and allied species, which now live so widely separated in the north and
south, and sometimes on the intermediate mountain-ranges, are removed." ...
"We cannot say why certain species and not others have migrated; why
certain species have been modified and have given rise to new forms, whilst
others have remained unaltered." Again he adds, "Various difficulties also
remain to be solved; for instance, the occurrence, as shown by Dr. Hooker,
of the same plants at points so enormously remote as Kerguelen Land, New
Zealand, and Fuegia; but icebergs, as suggested by Lyell, may have been
concerned in their dispersal. The existence, at these and other distant
points of the southern hemisphere, of species which, though distinct,
belong to genera exclusively confined to the south, is a more remarkable
case. Some of these species are so distinct that we cannot suppose that
there has been time since the commencement of the last glacial period for
their migration and subsequent modification to the necessary degree." Mr.
Darwin goes on to account for these facts by the probable existence of a
rich antarctic flora in a warm period anterior to the last glacial {151}
epoch. There are indeed many reasons for thinking that a southern
continent, rich in living forms, once existed. One such reason is the way
in which struthious birds are, or have been, distributed around the
antarctic region: as the ostrich in Africa, the rhea in South America, the
emeu in Australia, the apteryx, dinornis, &c. in New Zealand, the epiornis
in Madagascar. Still the existence of such a land would not alone explain
the various geographical cross relations which have been given above. It
would not, for example, account for the resemblance between the crustacea
or fishes of New Zealand and of England. It would, however, go far to
explain the identity (specific or generic) between fresh water and other
forms now simultaneously existing in Australia and South America, or in
either or both of these, and New Zealand.
Again, mutations of elevation small and gradual (but frequent and
intermitting), through enormous periods of time--waves, as it were, of land
rolling many times in many directions--might be made to explain many
difficulties as to geographical distribution, and any cases that remained
would probably be capable of explanation, as being isolated but allied
animal forms, now separated indeed, but being merely remnants of extensive
groups which, at an earlier period, were spread over the surface of the
earth. Thus none of the facts here given are any serious difficulty to the
doctrine of "evolution," but it is contended in this book that if other
considerations render it improbable that the manifestation of the
successive forms of life has been brought about by minute, indefinite, and
fortuitous variations, then these facts as to geographical distribution
intensify that improbability, and are so far worthy of attention.
All geographical difficulties of the kind would be evaded if we could
concede the probability of the independent origin, in different localities,
of the same organic forms in animals high in the scale of nature. {152}
Similar causes must produce similar results, and new reasons have been
lately adduced for believing, as regards the _lowest organisms_, that the
same forms can arise and manifest themselves independently. The difficulty
as to higher animals is, however, much greater, as (on the theory of
evolution) one acting force must always be the ancestral history in each
case, and this force must always tend to go on acting in the same groove
and direction in the future as it has in the past. So that it is difficult
to conceive that individuals, the ancestral history of which is very
different, can be acted upon by all influences, external and internal, in
such diverse ways and proportions that the results (unequals being added to
unequals) shall be equal and similar. Still, though highly improbable, this
cannot be said to be impossible; and if there _is_ an innate law of any
kind helping to determine specific evolution, this may more or less, or
entirely, neutralize or even reverse the effect of ancestral habit. Thus,
it is quite conceivable that a pleurodont lizard might have arisen in
Madagascar in perfect independence of the similarly-formed American
lacertilia: just as certain teeth of carnivorous and insectivorous
marsupial animals have been seen most closely to resemble those of
carnivorous and insectivorous placental beasts; just as, again, the paddles
of the Cetacea resemble, in the fact of a multiplication in the number of
the phalanges, the many-jointed feet of extinct marine reptiles, and as the
beak of the cuttle-fish or of the tadpole resembles that of birds. We have
already seen (in Chapter III.) that it is impossible, upon any hypothesis,
to escape admitting the independent origins of closely similar forms, It
may be that they are both more frequent and more important than is
generally thought.
That closely similar structures may arise without a genetic relationship
has been lately well urged by Mr. Ray Lankester.[159] He has brought {153}
this notion forward even as regards the bones of the skull in osseous
fishes and in mammals. He has done so on the ground that the probable
common ancestor of mammals and of osseous fishes was a vertebrate animal of
so low a type that it could not be supposed to have possessed a skull
differentiated into distinct bony elements--even if it was bony at all. If
this was so, then the cranial bones must have had an independent origin in
each class, and in this case we have the most strikingly harmonious and
parallel results from independent actions. For the bones of the skull in an
osseous fish are so closely conformed to those of a mammal, that "both
types of skull exhibit many bones in common," though "in each type some of
these bones acquire special arrangements and very different
magnitudes."[160] And no investigator of homologies doubts that a
considerable number of the bones which form the skull of any osseous fish
are distinctly homologous with the cranial bones of man. The occipital, the
parietal, and frontal, the bones which surround the internal ear, the
vomer, the premaxilla, and the quadrate bones, may be given as examples.
Now, if such close relations of homology can be brought about independently
of any but the most remote genetic affinity, it would be rash to affirm
dogmatically that there is any impossibility in the independent origin of
such forms as centetes and solenodon, or of genetically distinct
batrachians, as similar to each other as are some of the frogs of South
America and of Europe. At the same time such phenomena must at present be
considered as very improbable, from the action of ancestral habit, as
before stated.
We have seen, then, that the geographical distribution of animals presents
difficulties, though not insuperable ones, for the Darwinian hypothesis.
If, however, other reasons against it appear of any weight--if, especially,
there is reason to believe that geological time has not been {154}
sufficient for it, then it will be well to bear in mind the facts here
enumerated. These facts, however, are not opposed to the doctrine of
evolution; and if it could be established that closely similar forms had
really arisen in complete independence one of the other, they would rather
tend to strengthen and to support that theory. [Page 155]
* * * * *
CHAPTER VIII.
HOMOLOGIES.
Animals made-up of parts mutually related in various ways.--What
homology is.--Its various kinds.--Serial homology.--Lateral
homology.--Vertical homology.--Mr. Herbert Spencer's explanations.--An
internal power necessary, as shown by facts of comparative anatomy.--Of
teratology.--M. St. Hilaire.--Professor Burt
Wilder.--Foot-wings.--Facts of pathology.--Mr. James Paget.--Dr.
William Budd.--The existence of such an internal power of individual
development diminishes the improbability of an analogous law of
specific origination.
That concrete whole which is spoken of as "an individual" (such, _e.g._, as
a bird or a lobster) is formed of a more or less complex aggregation of
parts which are actually (from whatever cause or causes) grouped, together
in a harmonious interdependency, and which have a multitude of complex
relations amongst themselves.
The mind detects a certain number of these relations as it contemplates the
various component parts of an individual in one or other direction--as it
follows up different lines of thought. These perceived relations, though
subjective, _as relations_, have nevertheless an objective foundation as
real parts, or conditions of parts, of real wholes; they are, therefore,
true relations, such, _e.g._, as those between the right and left hand,
between the hand and the foot, &c.
The component parts of each concrete whole have also a relation of
resemblance to the parts of other concrete wholes, whether of the same{156}
or of different kinds, as the resemblance between the hands of two men, or
that between the hand of a man and the fore-paw of a cat.
Now, it is here contended that the relationships borne one to another by
various component parts, imply the existence of some innate, internal
condition, conveniently spoken of as a power or tendency, which is quite as
mysterious as is any innate condition, power, or tendency, resulting in the
orderly evolution of successive specific manifestations. These
relationships, as also this developmental power, will doubtless, in a
certain sense, be somewhat further explained as science advances. But the
result will be merely a shifting of the inexplicability a point backwards,
by the intercalation of another step between the action of the internal
condition or power and its external result. In the meantime, even if by
"Natural Selection" we could eliminate the puzzles of the "origin of
species," yet other phenomena, not less remarkable (namely, those noticed
in this chapter), would still remain unexplained and as yet inexplicable.
It is not improbable that, could we arrive at the causes conditioning all
the complex inter-relations between the several parts of one animal, we
should at the same time obtain the key to unlock the secrets of specific
origination.
It is desirable, then, to see what facts there are in animal organization
which point to innate conditions (powers and tendencies), as yet
unexplained, and upon which the theory of "Natural Selection" is unable to
throw any explanatory light.
The facts to be considered are the phenomena of "homology," and especially
of serial, bilateral, and vertical homology.
The word "homology" indicates such a relation between two parts that they
may be said in some sense to be "the same," or at least "of similar
nature." This similarity, however, does not relate to the _use_ to which
parts are put, but only to their relative position with regard to other
parts, or to their mode of origin. There are many kinds of {157}
homology,[161] but it is only necessary to consider the three kinds above
enumerated.
[Illustration: WINGBONES OF PTERODACTYLE, BAT, AND BIRD.]
The term "homologous" may be applied to parts in two individual animals of
different kinds, or to different parts of the same individual. Thus "the
right and left hands," or "joints of the backbone," or "the teeth of the
two jaws," are homologous parts of the same individual. But the arm of a
man, the fore-leg of the horse, the paddle of the whale, and the wing of
the bat and the bird are all also homologous parts, yet of another kind,
_i.e._ they are the same parts existing in animals of different species.
On the other hand, the wing of the humming-bird and the wing of the
humming-bird moth are not homologous at all, or in any sense; for the
resemblance between them consists solely in the use to which they are put,
and is therefore only a relation of _analogy_. There is no relation of
_homology_ between them, because they have no common resemblance as to
their relations to surrounding parts, or as to their mode of origin.
Similarly, there is no homology between the wing of the bat and that {158}
of the flying-dragon, for the latter is formed of certain ribs, and not of
limb bones.
[Illustration: SKELETON OF THE FLYING DRAGON.
(Showing the elongated ribs which support the flitting organ.)]
Homology may be further distinguished into (1) a relationship which, on
evolutionary principles, would be due to descent from a common ancestor, as
the homological relation between the arm-bone of the horse and that of the
ox, or between the singular ankle bones of the two lemurine genera,
cheirogaleus and galago, and which relation has been termed by Mr. Ray
Lankester "homogeny;"[162] and (2) a relationship induced, not
derived--such as exists between parts closely similar in relative position,
but with no genetic affinity, or only a remote one, as the homological
relation between the chambers of the heart of a bat and those of a {159}
bird, or the similar teeth of the thylacine and the dog before spoken of.
For this relationship Mr. Bay Lankester has proposed the term "homoplasy."
[Illustration: TARSAL BONES OF DIFFERENT LEMUROIDS.
(Right tarsus of Galago; left tarsus of Cheirogaleus.)]
[Illustration: A CENTIPEDE.]
"Serial homology" is a relation of resemblance existing between two or more
parts placed in series one behind the other in the same individual.
Examples of such homologues are the ribs, or joints of the backbone of{160}
a horse, or the limbs of a centipede. The latter animal is a striking
example of serial homology. The body (except at its two ends) consists of a
longitudinal series of similar segments. Each segment supports a pair of
limbs, and the appendages of all the segments (except as before) are
completely alike.
[Illustration: SQUILLA.]
A less complete case of serial homology is presented by Crustacea (animals
of the crab class), notably by the squilla and by the common lobster. In
the latter animal we have a six-jointed abdomen (the so-called tail), {161}
in front of which is a large solid mass (the cephalo-thorax), terminated
anteriorly by a jointed process (the rostrum). On the under surface of the
body we find a quantity of moveable appendages. Such are, _e.g._, feelers
(Fig. 9), jaws (Figs. 6, 7, and 8), foot-jaws (Fig. 5), claws and legs
(Figs. 3 and 4), beneath the cephalo-thorax; and flat processes (Fig. 2),
called "swimmerets," beneath the so-called tail or abdomen.
[Illustration: PART OF THE SKELETON OF THE LOBSTER.]
Now, these various appendages are distinct and different enough as we {162}
see them in the adult, but they all appear in the embryo as buds of similar
form and size, and the thoracic limbs at first consist each of two members,
as the swimmerets always do.
This shows what great differences may exist in size, in form, and in
function, between parts which are developmentally the same, for all these
appendages are modifications of one common kind of structure, which becomes
differently modified in different situations; in other words, they are
serial homologues.
The segments of the body, as they follow one behind the other, are also
serially alike, as is plainly seen in the abdomen or tail. In the
cephalo-thorax of the lobster, however, this is disguised. It is therefore
very interesting to find that in the other crustacean before mentioned, the
squilla, the segmentation of the body is more completely preserved, and
even the first three segments, which go to compose the head, remain
permanently distinct.
[Illustration: SPINE OF GALAGO ALLENII.]
Such an obvious and unmistakeable serial repetition of parts does not
obtain in the highest, or backboned animals, the Vertebrata. Thus in man
and other mammals, nothing of the kind is _externally_ visible, and we have
to penetrate to his skeleton to find such a series of homologous parts.
There, indeed, we discover a number of pairs of bones, each pair so
obviously resembling the others, that they all receive a common name--the
ribs. There also (_i.e._ in the skeleton) we find a still more remarkable
series of similar parts, the joints of the spine or backbone (vertebræ),
which are admitted by all to possess a certain community of structure.{163}
It is in their limbs, however, that the Vertebrata present the most obvious
and striking serial homology--almost the only serial homology noticeable
externally.
The facts of serial homology seem hardly to have excited the amount of
interest they certainly merit.
Very many writers, indeed, have occupied themselves with investigations and
speculations as to what portions of the leg and foot answer to what parts
of the arm and hand, a question which has only recently received a more or
less satisfactory solution through the successive concordant efforts of
Professor Humphry,[163] Professor Huxley,[164] the Author of this
work,[165] and Professor Flower.[166] Very few writers, however, have
devoted much time or thought to the question of serial homology in general.
Mr. Herbert Spencer, indeed, in his very interesting "First Principles of
Biology," has given forth ideas on this subject, which are well worthy
careful perusal and consideration, and some of which apply also to the
other kinds of homology mentioned above. He would explain the serial
homologies of such creatures as the lobster and centipede thus: Animals of
a very low grade propagate themselves by spontaneous fission. If certain
creatures found benefit from this process of division remaining incomplete,
such creatures (on the theory of "Natural Selection") would transmit their
selected tendency to such incomplete division to their posterity. In this
way, it is conceivable, that animals might arise in the form of long chains
of similar segments, each of which chains would consist of a number of
imperfectly separated individuals, and be equivalent to a series of
separate individuals belonging to kinds in which the fission was complete.
In other words, Mr. Spencer would explain it as the coalescence of {164}
organisms of a lower degree of aggregation in one longitudinal series,
through survival of the fittest aggregations. This may be so. It is
certainly an ingenious speculation, but facts have not yet been brought
forward which demonstrate it. Had they been so, this kind of serial
homology might be termed "homogenetic."
The other kind of serial repetitions, namely, those of the vertebral
column, are explained by Mr. Spencer as the results of alternate strains
and compressions acting on a primitively homogeneous cylinder. The serial
homology of the fore and hind limbs is explained by the same writer as the
result of a similarity in the influences and conditions to which they are
exposed. Serial homologues so formed might be called, as Mr. Ray Lankester
has proposed, "homoplastic." But there are, it is here contended, abundant
reasons for thinking that the predominant agent in the production of the
homologies of the limbs is an _internal_ force or tendency. And if such a
power can be shown to be necessary in this instance, it may also be
legitimately used to explain such serial homologies as those of the
centipede's segments and of the joints of the backbone. At the same time it
is not, of course, pretended that external conditions do not contribute
their own effects in addition. The presence of this internal power will be
rendered more probable if valid arguments can be brought forward against
the explanations which Mr. Herbert Spencer has offered.
_Lateral homology_ (or bilateral symmetry) is the resemblance between the
right and left sides of an animal, or of part of an animal; as, _e.g._,
between our right hand and our left. It exists more or less at one or other
time of life in all animals, except some very lowly organized creatures. In
the highest animals this symmetry is laid down at the very dawn of life,
the first trace of the future creature being a longitudinal streak--the
embryonic "primitive groove." This kind of homology is explained by Mr.
Spencer as the result of the similar way in which conditions affect {165}
the right and left sides respectively.
[Illustration: VERTEBRÆ OF AXOLOTL.]
_Vertical homology_ (or vertical symmetry) is the resemblance existing
between parts which are placed one above the other beneath. It is much less
general and marked than serial, or lateral homology. Nevertheless, it is
plainly to be seen in the tail region of most fishes, and in the
far-extending dorsal (back) and ventral (belly) fins of such kinds as the
sole and the flounder.
It is also strikingly shown in the bones of the tail of certain efts, as in
_Chioglossa_, where the complexity of the upper (neural) arch is closely
repeated by the inferior one. Again, in _Spelerpes rubra_, where almost
vertically ascending articular processes above are repeated by almost
vertically descending articular processes below. Also in the axolotl, where
there are douple pits, placed side by side, not only superiorly but at the
same time inferiorly.[167]
This kind of homology is also explained by Mr. Spencer as the result of the
similarity of conditions affecting the two parts. Thus he explains the very
general absence of symmetry between the dorsal and ventral surfaces of
animals by the different conditions to which these two surfaces are
respectively exposed, and in the same way he explains the asymmetry of the
flat-fishes (_Pleuronectidæ_), of snails, &c.
Now, first, as regards Mr. Spencer's explanation of animal forms by means
of the influence of external conditions, the following observations may be
made. Abundant instances are brought forward by him of admirable adaptation
of structure to circumstances, but as to the immense majority of these it
is very difficult, if not impossible, to see _how_ external conditions{166}
can have produced, or even tended to have produced them. For example, we
may take the migration of one eye of the sole to the other side of its
head. What is there here either in the darkness, or the friction, or in any
other conceivable external cause, to have produced the first beginning of
such an unprecedented displacement of the eye? Mr. Spencer has beautifully
illustrated that correlation which all must admit to exist between the
forms of organisms and their surrounding external conditions, but by no
means proved that the latter are _the cause_ of the former.
[Illustration: PLEURONECTIDÆ, WITH THE PECULIARLY PLACED EYE IN DIFFERENT
POSITIONS.]
Some internal conditions (or in ordinary language some internal power and
force) must be conceded to living organisms, otherwise incident forces must
act upon them and upon non-living aggregations of matter in the same way
and with similar effects.
If the mere presence of these incident forces produces so ready a response
in animals and plants, it must be that there are, in their case, conditions
disposing and enabling them so to respond, according to the old maxim,
_Quicquid recipitur, recipitur ad modum recipientis_, as the same rays of
light which bleach a piece of silk, blacken nitrate of silver. If,
therefore, we attribute the forms of organisms to the action of {167}
external conditions, _i.e._ of incident forces on their modifiable
structure, we give but a partial account of the matter, removing a step
back, as it were, the action of the internal condition, power, or force
which must be conceived as occasioning such ready modifiability. But indeed
it is not at all easy to see how the influence of the surface of the ground
or any conceivable condition or force can produce the difference which
exists between the ventral and dorsal shields of the carapace of a
tortoise, or by what differences of merely external causes the ovaries of
the two sides of the body can be made equal in a bat and unequal in a bird.
[Illustration: AN ECHINUS, OR SEA-URCHIN.
(The spines removed from one-half.)]
There is, on the other hand, an _a priori_ reason why we should expect to
find that the symmetrical forms of all animals are due to internal causes.
This reason is the fact that the symmetrical forms of minerals are
undoubtedly due to such causes. It is unnecessary here to do more than
allude to the beautiful and complex forms presented by inorganic
structures. With regard to organisms, however, the wonderful Acanthometræ
and the Polycystina may be mentioned as presenting complexities of form
which can hardly be thought to be due to other than _internal_ causes. The
same may be said of the great group of Echinoderms, with their amazing{168}
variety of component parts. If then internal forces can so build up the
most varied structures, they are surely capable of producing the serial,
lateral, and vertical symmetries which higher animal forms exhibit. Mr.
Spencer is the more bound to admit this, inasmuch as in his doctrine of
"physiological units" he maintains that these organic atoms of his have an
innate power of building up and evolving the whole and perfect animal from
which they were in each case derived. To build up and evolve the various
symmetries here spoken of is not one whit more mysterious. Directly to
refute Mr. Spencer's assertion, however, would require the bringing forward
of examples of organisms which are ill-adapted to their positions, and out
of harmony with their surroundings--a difficult task indeed.[168]
Secondly, as regards the last-mentioned author's explanation of such serial
homology as exists in the centipede and its allies, the very groundwork is
open to objection. Multiplication by spontaneous fission seems from some
recent researches to be much less frequent than has been supposed, and more
evidence is required as to the fact of the habitual propagation of _any_
planariæ in this fashion.[169] But even if this were as asserted, {169}
nevertheless it fails to explain the peculiar condition presented by
_Syllis_ and some other annelids, where a new head is formed at intervals
in certain segments of the body. Here there is evidently an innate tendency
to the development at intervals of a complex whole. It is not the budding
out or spontaneous fission of certain segments, but the transformation in a
definite and very peculiar manner of parts which already exist into other
and more complex parts. Again, the processes of development presented by
some of these creatures do not by any means point to an origin through{170}
the linear coalescence of primitively distinct animals by means of
imperfect segmentation. Thus in certain Diptera (two winged flies) the
legs, wings, eyes, &c., are derived from masses of formative tissue (termed
imaginal disks), which by their mutual approximation together build up
parts of the head and body,[170] recalling to mind the development of
Echinoderms.
[Illustration: AN ANNELID DIVIDING SPONTANEOUSLY.
(A new head having been formed towards the hinder end of the body of the
parent.)]
Again, Nicholas Wagner found in certain other Diptera, the Hessian flies,
that the larva gives rise to secondary larvæ within it, which develop and
burst the body of the primary larva. The secondary larvæ give rise,
similarly, to another set within them, and these again to another[171] set.
Again, the fact that in _Tænia echinococcus_ one egg produces numerous
individuals, tends to invalidate the argument that the increase of segments
during development is a relic of specific genesis.
Mr. H. Spencer seems to deny serial homology to the mollusca, but it is
difficult to see why the shell segments of chiton are not such homologues
because the segmentation is superficial. Similarly the external processes
of eolis, doris, &c., are good examples of serial homology, as also are
plainly the successive chambers of the orthoceratidæ. Nor are parts of a
series less serial, because arranged spirally, as in most gasteropods. Mr.
Spencer observes of the molluscous as of the vertebrate animal, "You cannot
cut it into transverse slices, each of which contains a digestive organ, a
respiratory organ, a reproductive organ, &c."[172] But the same may be said
of every single arthropod and annelid if it be meant that all these organs
are not contained in every possible slice. While if it be meant that parts
of all such organs are contained in certain slices, then some of the
mollusca may also be included.
Another objection to Mr. Spencer's speculation is derived from
considerations which have already been stated, as to past time. For if{171}
the annulose animals have been formed by aggregation, we ought to find this
process much less perfect in the oldest form. But a complete development,
such as already obtains in the lobster, &c., was reached by the Eurypterida
and Trilobites of the palæozoic strata; and annelids, probably formed
mainly like those of the present day, abounded during the deposition of the
oldest fossiliferous rocks.
[Illustration: TRILOBITE.]
Thirdly, and lastly, as regards such serial homology as is exemplified by
the backbone of man, there are also several objections to Mr. Spencer's
mechanical explanation.
On the theory of evolution most in favour, the first Vertebrata were
aquatic. Now, as natation is generally effected by repeated and vigorous
lateral flexions of the body, we ought to find the segmentation much more
complete laterally than on the dorsal and ventral aspects of the spinal
column. Nevertheless, in those species which, taken together, constitute a
series of more and more distinctly segmented forms, the segmentation
gradually increases _all round_ the central part of the spinal column.
Mr. Spencer[173] thinks it probable that the sturgeon has retained the
notochordal (that is, the primitive, unsegmented) structure because it{172}
is sluggish. But Dr. Günther informs me that the sluggishness of the common
tope (_Galeus vulgaris_) is much like that of the sturgeon, and yet the
bodies of its vertebræ are distinct and well-ossified. Moreover, the great
salamander of Japan is much more inert and sluggish than either, and yet it
has a well-developed, bony spine.
I can learn nothing of the habits of the sharks _Hexanchus_, _Heptanchus_,
and _Echinorhinus_, but Müller describes them as possessing a persistent
_chorda dorsalis_.[174] It may be they have the habits of the tope, but
other sharks are amongst the very swiftest and most active of fishes.
In the bony pike (_lepidosteus_), the rigidity of the bony scales by which
it is completely enclosed must prevent any excessive flexion of the body,
and yet its vertebral column presents a degree of ossification and
vertebral completeness greater than that found in any other fish whatever.
Mr. Spencer supports his argument by the non-segmentation of the anterior
end of the skeletal axis, _i.e._ by the non-segmentation of the skull. But
in fact the skull _is_ segmented, and, according to the quasi-vertebral
theory of the skull put forward by Professor Huxley,[175] is probably
formed of a number of coalesced segments, of some of which the trabeculæ
cranii and the mandibular and hyoidean arches are indications. What is,
perhaps, most remarkable however is, that the segmentation of the
skull--its separation into the three occipital, parietal, and frontal
elements--is most complete and distinct in the highest class, and this can
have nothing, however remotely, to do with the cause suggested by Mr.
Spencer.
Thus, then, there is something to be said in opposition to both the
aggregational and the mechanical explanations of serial homology. The
explanations suggested are very ingenious, yet repose upon a very {173}
small basis of fact. Not but that the process of vertebral segmentation may
have been sometimes assisted by the mechanical action suggested.
It remains now to consider what are the evidences in support of the
existence of an internal power, by the action of which these homological
manifestations are evolved. It is here contended that there _is_ good
evidence of the existence of some such special internal power, and that not
only from facts of comparative anatomy, but also from those of
teratology[176] and pathology. These facts appear to show, not only that
there are homological internal relations, but that they are so strong and
energetic as to re-assert and re-exhibit themselves in creatures which, on
the Darwinian theory, are the descendants of others in which they were much
less marked. They are, in fact, sometimes even more plain and distinct in
animals of the highest types than in inferior forms, and, moreover, this
deep-seated tendency acts even in diseased and abnormal conditions.
Mr. Darwin recognizes[177] these homological relations, and does "not doubt
that they may be mastered more or less completely by Natural Selection." He
does not, however, give any explanation of these phenomena other than the
imposition on them of the name "laws of correlation;" and indeed he says,
"The nature of the bond of correlation is frequently quite obscure." Now,
it is surely more desirable to make use, if possible, of one conception
than to imagine a number of, to all appearance, separate and independent
"laws of correlation" between different parts of each animal.
[Illustration: THE AARD-VARK (ORYCTEROPUS).]
[Illustration: THE PANGOLIN (MANIS).]
But even some of these alleged laws hardly appear well founded. Thus Mr.
Darwin, in support of such a law of concomitant variation as regards hair
and teeth, brings forward the case of Julia Pastrana,[178] and a man {174}
of the Burmese Court, and adds,[179] "These cases and those of the hairless
dogs forcibly call to mind the fact that the two orders of mammals, namely,
the Edentata and Cetacea, which are the most abnormal in their dermal
covering, are likewise the most abnormal either by deficiency or redundancy
of teeth." The assertion with regard to these orders is certainly true, but
it should be borne in mind at the same time that the armadillos, which are
much more abnormal than are the American anteaters as regards their dermal
covering, in their dentition are less so. The Cape ant-eater, on the other
hand, the Aard-vark (Orycteropus), has teeth formed on a type quite
different from that existing in any other mammal; yet its hairy coat is not
known to exhibit any such strange peculiarity. Again, those remarkable
scaly ant-eaters of the Old World--the pangolins (Manis)--stand alone
amongst mammals as regards their dermal covering; having been classed {175}
with lizards by early naturalists on account of their clothing of scales,
yet their mouth is like that of the hairy ant-eaters of the New World. On
the other hand, the duck-billed platypus of Australia (Ornithorhynchus) is
the only mammal which has teeth formed of horn, yet its furry coat is
normal and ordinary. Again, the Dugong and Manatee are dermally alike, yet
extremely different as regards the structure and number of their teeth. The
porcupine also, in spite of its enormous armature of quills, is furnished
with as good a supply of teeth as are the hairy members of the same family,
but not with a better one; and in spite of the deficiency of teeth in the
hairless dogs, no converse redundancy of teeth has, it is believed, been
remarked in Angora cats and rabbits. To say the least, then, this law {176}
of correlation presents numerous and remarkable exceptions.
[Illustration: DUGONG.]
To return, however, to the subject of homological relations: it is surely
inconceivable that indefinite variation with survival of the fittest can
ever have built up these serial, bilateral, and vertical homologies,
without the action of some special innate power or tendency so to build up,
possessed by the organism itself in each case. By "special tendency" is
meant one the laws and conditions of which are as yet unknown, but which is
analogous to the innate power and tendency possessed by crystals similarly,
to build up certain peculiar and very definite forms.
First, with regard to comparative anatomy. The correspondence between the
thoracic and pelvic limbs is notorious. Professor Gegenbaur has lately
endeavoured[180] to explain this resemblance by the derivation of each limb
from a primitive form of fin. This fin is supposed to have had a marginal
external (radial) series of cartilages, each of which supported a series of
secondary cartilages, starting from the inner (ulnar) side of the distal
part of the supporting marginal piece. The root marginal piece would become
the humerus or femur, as the case might be: the second marginal piece, with
the piece attached to the inner side of the distal end of the root marginal
piece, would together form either the radius and ulna or the tibia and
fibula, and so on.
Now there is little doubt (from _a priori_ considerations) but that the
special differentiation of the limb bones of the higher Vertebrates has
been evolved from anterior conditions existing in some fish-like form or
other. But the particular view advocated by the learned Professor is open
to criticism. Thus, it may be objected against this view, first, that it
takes no account of the radial ossicle which becomes so enormous in the
mole; secondly, that it does not explain the extra series of ossicles {177}
which are formed on the _outer_ (radial or marginal) side of the paddle in
the Ichthyosaurus; and thirdly, and most importantly, that even if this had
been the way in which the limbs had been differentiated, it would not be at
all inconsistent with the possession of an innate power of producing, and
an innate tendency to produce similar and symmetrical homological
resemblances. It would not be so because resemblances of the kind are found
to exist, which, on the Darwinian theory, must be subsequent and secondary,
not primitive and ancestral. Thus we find in animals of the eft kind
(certain amphibians), in which the tarsus is cartilaginous, that the carpus
is cartilaginous likewise. And we shall see in cases of disease and of
malformation what a tendency there is to a similar affection of homologous
parts. In efts, as Professor Gegenbaur himself has pointed out,[181] there
is a striking correspondence between the bones or cartilages supporting the
arm, wrist, and fingers, and those sustaining the leg, ankle, and toes,
with the exception that the toes exceed the fingers in number by one.
[Illustration: SKELETON OF AN ICHTHYOSAURUS.]
[Illustration: A. SKELETON OF ANTERIOR EXTREMITY OF AN EFT.
B. SKELETON OF POSTERIOR EXTREMITY OF THE SAME.]
Yet these animals are far from being the root-forms from which all the
Vertebrata have diverged, as is evidenced from the degree of specialization
which their structure presents. If they have descended from such {178}
primitive forms as Professor Gegenbaur imagines, then they have built up a
secondary serial homology--a repetition of similar modifications--fully as
remarkable as if it were primary. The Plesiosauria--those extinct marine
reptiles of the Secondary period, with long necks, small heads, and
paddle-like limbs--are of yet higher organization than are the efts and
other Amphibia. Nevertheless they present us with a similarity of structure
between the fore and hind limb, which is so great as almost to be {179}
identity. But the Amphibia and Plesiosauria, though not themselves
primitive vertebrate types, may be thought by some to have derived their
limb-structure by direct descent from such. Tortoises, however, must be
admitted to be not only highly differentiated organisms, but to be far
indeed removed from primeval vertebrate structure. Yet certain
tortoises[182] (notably _Chelydra Temminckii_) exhibit such a remarkable
uniformity in fore and hind limb structure (extending even up to the
proximal ends of the humerus and femur) that it is impossible to doubt its
independent development in these forms.
[Illustration: SKELETON OF A PLESIOSAURUS.]
Again in the Potto (Perodicticus) there is an extra bone in the foot,
situated in the transverse ligament enclosing the flexor tendons. It is
noteworthy that in the _hand_ of the same animal a serially homologous
structure should also be developed.[183] In the allied form called the slow
lemur (Nycticebus) we have certain arrangements of the muscles and tendons
of the hand which reproduce in great measure those of the foot and _vice
versâ_.[184] And in the Hyrax another myological resemblance appears.[185]
It is, however, needless to multiply instances which can easily be produced
in large numbers if required.
Secondly, with regard to teratology, it is notorious that similar
abnormalities are often found to co-exist in both the pelvic and thoracic
limbs.
M. Isidore Geoffroy St. Hilaire remarks,[186] "L'anomalie se répète d'un
membre thoracique au membre abdominal du même côté." And he afterwards
quotes from Weitbrecht,[187] who had "observé dans un cas l'absence
simultanée aux deux mains et aux deux pieds, de quelques doigts, de {180}
quelques metacarpiens et metatarsiens, enfin de quelques os du carpe et du
tarse."
[Illustration: LONG FLEXOR MUSCLES AND TENDONS OF THE HAND.
_P.t._ Pronator teres. _F.s._ Flexor sublimis digitorum. _F.p._ Flexor
profundus digitorum. _F.l.p._ Flexor longus pollicis.]
Professor Burt G. Wilder, in his paper on extra digits,[188] has {181}
recorded no less than twenty-four cases where such excess coexisted in both
little fingers; also one case in which the right little finger and little
toe were so affected; six in which it was both the little fingers and both
the little toes; and twenty-two other cases more or less the same, but in
which the details were not accurately to be obtained.
Mr. Darwin cites[189] a remarkable instance of what he is inclined to
regard as the development in the foot of birds of a sort of representation
of the wing-feathers of the hand. He says: "In several distinct breeds of
the pigeon and fowl the legs and the two outer toes are heavily feathered,
so that, in the trumpeter pigeon, they appear like little wings. In the
feather-legged bantam, the 'boots,' or feathers, which grow from the
outside of the leg, and generally from the two outer toes, have, according
to the excellent authority of Mr. Hewitt, been seen to exceed the
wing-feathers in length, and in one case were actually nine and a half
inches in length! As Mr. Blyth has remarked to me, these leg-feathers
resemble the primary wing-feathers, and are totally unlike the fine down
which naturally grows on the legs of some birds, such as grouse and owls.
Hence it may be suspected that excess of food has first given redundancy to
the plumage, and then that the law of homologous variation has led to the
development of feathers on the legs, in a position corresponding with those
on the wing, namely, on the outside of the tarsi and toes. I am
strengthened in this belief by the following curious case of correlation,
which for a long time seemed to me utterly inexplicable,--namely, that in
pigeons of any breed, if the legs are feathered, the two outer toes are
partially connected by skin. These two outer toes correspond with our third
and fourth toes. Now, in the wing of the pigeon, or any other bird, the
first and fifth digits are wholly aborted; the second is rudimentary, and
carries the so-called 'bastard wing;' whilst the third and fourth {182}
digits are completely united and enclosed by skin, together forming the
extremity of the wing. So that in feather-footed pigeons not only does the
exterior surface support a row of long feathers like wing-feathers, but the
very same digits which in the wing are completely united by skin become
partially united by skin in the feet; and thus, by the law of the
correlated variation of homologous parts, we can understand the curious
connexion of feathered legs and membrane between the outer toes."
Irregularities in the circulating system are far from uncommon, and
sometimes illustrate this homological tendency. My friend and colleague Mr.
George G. Gascoyen, assistant surgeon at St. Mary's Hospital, has supplied
me with two instances of symmetrical affections which have come under his
observation.
In the first of these the brachial artery bifurcated almost at its origin,
the two halves re-uniting at the elbow-joint, and then dividing into the
radial and ulnar arteries in the usual manner. In the second case an
aberrant artery was given off from the radial side of the brachial artery,
again almost at its origin. This aberrant artery anastomosed below the
elbow-joint with the radial side of the radial artery. In each of these
cases the right and left sides varied in precisely the same manner.
Thirdly, as to pathology. Mr. James Paget,[190] speaking of symmetrical
diseases, says: "A certain morbid change of structure on one side of the
body is repeated in the exactly corresponding part of the other side." He
then quotes and figures a diseased lion's pelvis from the College of
Surgeons Museum, and says of it: "Multiform as the pattern is in which the
new bone, the product of some disease comparable with a human rheumatism,
is deposited--a pattern more complex and irregular than the spots upon a
map--there is not one spot or line on one side which is not represented, as
exactly as it would be in a mirror, on the other. The likeness has more
than daguerreotype exactness." He goes on to observe: "I need not {183}
describe many examples of such diseases. Any out-patients' room will
furnish abundant instances of exact symmetry in the eruptions of eczema,
lepra, and psoriasis; in the deformities of chronic rheumatism, the
paralyses from lead; in the eruptions excited by iodide of potassium or
copaiba. And any large museum will contain examples of equal symmetry in
syphilitic ulcerations of the skull; in rheumatic and syphilitic deposits
on the tibiæ and other bones; in all the effects of chronic rheumatic
arthritis, whether in the bones, the ligaments, or the cartilages; in the
fatty and earthy deposits in the coats of arteries."[191]
He also considered it to be proved that, "Next to the parts which are
symmetrically placed, none are so nearly identical in composition as those
which are homologous. For example, the backs of the hands and of the feet,
or the palms and soles, are often not only symmetrically, but similarly,
affected with psoriasis. So are the elbows and the knees; and similar
portions of the thighs and the arms may be found affected with ichthyosis.
Sometimes also specimens of fatty and earthy deposits in the arteries
occur, in which exact similarity is shown in the plan, though not in the
degree, with which the disease affects severally the humeral and femoral,
the radial and peroneal, the ulnar and posterior tibial arteries."
Dr. William Budd[192] gives numerous instances of symmetry in disease, both
lateral and serial. Thus, amongst others, we have one case (William
Godfrey), in which the hands and feet were distorted. "The distortion of
the right hand is greater than that of the left, of the right foot greater
than that of the left foot." In another (Elizabeth Alford) lepra affected
the extensor surfaces of the thoracic and pelvic limbs. Again, in the case
of skin disease illustrated in Plate III., "The analogy between the {184}
elbows and knees is clearly expressed in the fact that these were the only
parts affected with the disease."[193]
Professor Burt Wilder,[194] in his paper on "Pathological Polarities,"
strongly supports the philosophical importance of these peculiar relations,
adding arguments in favour of antero-posterior homologies, which it is here
unnecessary to discuss, enough having been said, it is believed, to
thoroughly demonstrate the existence of these deep internal relations which
are named lateral and serial homologies.
What explanation can be offered of these phenomena? To say that they
exhibit a "nutritional relation" brought about by a "balancing of forces"
is merely to give a new denomination to the unexplained fact. The changes
are, _of course_, brought about by a "nutritional" process, and the
symmetry is undoubtedly the result of a "balance of forces," but to say so
is a truism. The question is, what is the cause of this "nutritional
balancing"? It is here contended that it must be due to an internal cause
which at present science is utterly incompetent to explain. It is an
internal property possessed by each living organic whole as well as by each
non-living crystalline mass, and that there is such internal power or
tendency, which may be spoken of as a "polarity," seems to be demonstrated
by the instances above given, which can easily be multiplied indefinitely.
Mr. Herbert Spencer[195] (speaking of the reproduction, by budding, of a
Begonia-leaf) recognizes a power of the kind. He says, "We have, therefore,
no alternative but to say that the living particles composing one of these
fragments have an innate tendency to arrange themselves into the shape of
the organism to which they belong. We must infer that a plant or animal of
any species is made up of special units, in all of which there dwells the
intrinsic aptitude to aggregate into the form of that species; just as{185}
in the atoms of a salt, there dwells the intrinsic aptitude to crystallize
in a particular way. It seems difficult to conceive that this can be so;
but we see that it _is_ so." ... "For this property there is no fit term.
If we accept the word polarity as a name for the force by which inorganic
units are aggregated into a form peculiar to them, we may apply this word
to the analogous force displayed by organic limits."
Dr. Jeffries Wyman,[196] in his paper on the "Symmetry and Homology of
Limbs," has a distinct chapter on the "Analogy between Symmetry and
Polarity," illustrating it by the effects of magnets on "particles in a
polar condition."
Mr. J. J. Murphy, after noticing[197] the power which crystals have to
repair injuries inflicted on them and the modifications they undergo
through the influence of the medium in which they may be formed, goes on to
say:[198] "It needs no proof that in the case of spheres and crystals the
forms and the structures are the effect, and not the cause, of the
formative principles. Attraction, whether gravitative or capillary,
produces the spherical form; the spherical form does not produce
attraction. And crystalline polarities produce crystalline structure and
form; crystalline structure and form do not produce crystalline polarities.
The same is not quite so evident of organic forms, but it is equally true
of them also." ... "It is not conceivable that the microscope should reveal
peculiarities of structure corresponding to peculiarities of habitual
tendency in the embryo, which at its first formation has no structure
whatever;"[199] and he adds that "there is something quite inscrutable and
mysterious" in the formation of a new individual from the germinal {186}
matter of the embryo. In another place[200] he says: "We know that in
crystals, notwithstanding the variability of form within the limits of the
same species, there are definite and very peculiar formative laws, which
cannot possibly depend on anything like organic functions, because crystals
have no such functions; and it ought not to surprise us if there are
similar formative or morphological laws among organisms, which, like the
formative laws of crystallization, cannot be referred to any relation of
form or structure to function. Especially, I think, is this true of the
lowest organisms, many of which show great beauty of form, of a kind that
appears to be altogether due to symmetry of growth; as the beautiful
star-like rayed forms of the _acanthometræ_, which are low animal organisms
not very different from the Foraminifera." Their "definiteness of form does
not appear to be accompanied by any corresponding differentiation of
function between different parts; and, so far as I can see, the beautiful
regularity and symmetry of their radiated forms are altogether due to
unknown laws of symmetry of growth, just like the equally beautiful and
somewhat similar forms of the compound six-rayed, star-shaped crystals of
snow."
Altogether, then, it appears that each organism has an innate tendency to
develop in a symmetrical manner, and that this tendency is controlled and
subordinated by the action of external conditions, and not that this
symmetry is superinduced only _ab externo_. In fact, that each organism has
its own internal and special laws of growth and development.
If, then, it is still necessary to conceive an internal law or "substantial
form," moulding each organic being,[201] and directing its development{187}
as a crystal is built up, only in an indefinitely more complex manner, it
is congruous to imagine the existence of some internal law accounting at
the same time for specific divergence as well as for specific identity.
A principle regulating the successive evolution of different organic forms
is not one whit more mysterious than is the mysterious power by which a
particle of structureless sarcode develops successively into an egg, a
grub, a chrysalis, a butterfly, when all the conditions, cosmical,
physical, chemical, and vital, are supplied, which are the requisite
accompaniments to determine such evolution. [Page 188]
* * * * *
CHAPTER IX.
EVOLUTION AND ETHICS.
The origin of morals an inquiry not foreign to the subject of this
book.--Modern utilitarian view as to that origin.--Mr. Darwin's
speculation as to the origin of the abhorrence of incest.--Cause
assigned by him insufficient.--Care of the aged and infirm opposed by
"Natural Selection;" also self-abnegation and asceticism.--Distinctness
of the ideas "right" and "useful."--Mr. John Stuart
Mill.--Insufficiency of "Natural Selection" to account for the origin
of the distinction between duty and profit.---Distinction of moral acts
into "material" and "formal."--No ground for believing that formal
morality exists in brutes.--Evidence that it does exist in
savages.--Facility with which savages may be misunderstood.--Objections
as to diversity of customs.--Mr. Hutton's review of Mr. Herbert
Spencer.--Anticipatory character of morals.--Sir John Lubbock's
explanation.--Summary and conclusion.
Any inquiry into the origin of the notion of "morality"--the conception of
"right"--may, perhaps, be considered as somewhat remote from the question
of the Genesis of Species; the more so, since Mr. Darwin, at one time,
disclaimed any pretension to explain the origin of the higher psychical
phenomena of man. His disciples, however, were never equally reticent, and
indeed he himself is now not only about to produce a work on man (in which
this question must be considered), but he has distinctly announced the
extension of the application of his theory to the very phenomena in
question. He says:[202] "In the distant future I see open fields for {189}
far more important researches. Psychology will be based on a new
foundation, that of the necessary acquirement of each mental power and
capacity by gradation. Light will be thrown on the origin of man and his
history." It may not be amiss then to glance slightly at the question, so
much disputed, concerning the origin of ethical conceptions and its bearing
on the theory of "Natural Selection."
The followers of Mr. John Stuart Mill, of Mr. Herbert Spencer, and
apparently, also, of Mr. Darwin, assert that in spite of the great
_present_ difference between the ideas "useful" and "right," yet that they
are, nevertheless, one in _origin_, and that that origin consisted
ultimately of pleasurable and painful sensations.
They say that "Natural Selection" has evolved moral conceptions from
perceptions of what was useful, _i.e._ pleasurable, by having through long
ages preserved a predominating number of those individuals who have had a
natural and spontaneous liking for practices and habits of mind useful to
the race, and that the same power has destroyed a predominating number of
those individuals who possessed a marked tendency to contrary practices.
The descendants of individuals so preserved have, they say, come to inherit
such a liking and such useful habits of mind, and that at last (finding
this inherited tendency thus existing in themselves, distinct from their
tendency to conscious self-gratification) they have become apt to regard it
as fundamentally distinct, _innate_, and independent of all experience. In
fact, according to this school, the idea of "right" is only the result of
the gradual accretion of useful predilections which, from time to time,
arose in a series of ancestors naturally selected. In this way, "morality"
is, as it were, the congealed past experience of the race, and "virtue"
becomes no more than a sort of "retrieving," which the thus improved human
animal practises by a perfected and inherited habit, regardless of
self-gratification, just as the brute animal has acquired the habit of
seeking prey and bringing it to his master, instead of devouring it {190}
himself.
Though Mr. Darwin has not as yet expressly advocated this view, yet some
remarks made by him appear to show his disposition to sympathise with it.
Thus, in his work on "Animals and Plants under Domestication,"[203] he
asserts that "the savages of Australia and South America hold the crime of
incest in abhorrence;" but he considers that this abhorrence has probably
arisen by "Natural Selection," the ill effects of close interbreeding
causing the less numerous and less healthy offspring of incestuous unions
to disappear by degrees, in favour of the descendants (greater both in
number and strength) of individuals who naturally, from some cause or
other, as he suggests, preferred to mate with strangers rather than with
close blood-relations; this preference being transmitted and becoming thus
instinctive, or habitual, in remote descendants.
But on Mr. Darwin's own ground, it maybe objected that this notion fails to
account for "abhorrence," and "moral reprobation;" for, as no stream can
rise higher than its source, the original "slight feeling" which was
_useful_ would have been perpetuated, but would never have been augmented
beyond the degree requisite to ensure this beneficial preference, and
therefore would not certainly have become magnified into "abhorrence." It
will not do to assume that the union of males and females, each possessing
the required "slight feeling," must give rise to offspring with an
intensified feeling of the same kind; for, apart from reversion, Mr. Darwin
has called attention to the unexpected modifications which sometimes result
from the union of _similarly_ constituted parents. Thus, for example, he
tells us:[204] "If two top-knotted canaries are matched, the young, instead
of having very fine top-knots, are generally bald." From examples of this
kind, it is fair, on Darwinian principles, to infer that the union of {191}
parents who possessed a similar inherited aversion might result in
phenomena quite other than the augmentation of such aversion, even if the
two aversions should be altogether similar; while, very probably, they
might be so different in their nature as to tend to neutralize each other.
Besides, the union of parents so similarly emotional would be rare indeed
amongst savages, where marriages would be owing to almost anything rather
than to congeniality of mind between the spouses. Mr. Wallace tells
us,[205] that they choose their wives for "rude health and physical
beauty," and this is just what might be naturally supposed. Again, we must
bear in mind the necessity there is that _many individuals_ should be
similarly and simultaneously affected with this aversion from
consanguineous unions; as we have seen in the second chapter, how
infallibly variations presented by only a few individuals, tend to be
eliminated by mere force of numbers. Mr. Darwin indeed would throw back
this aversion, if possible, to a pre-human period; since he speculates as
to whether the gorillas or orang-utans, in effecting their matrimonial
relations, show any tendency to respect the prohibited degrees of
affinity.[206] No tittle of evidence, however, has yet been adduced
pointing in any such direction, though surely if it were of such importance
and efficiency as to result (through the aid of "Natural Selection" alone)
in that "abhorrence" before spoken of, we might expect to be able to detect
unmistakeable evidence of its incipient stages. On the contrary, as regards
the ordinary apes (for with regard to the highest there is no evidence of
the kind) as we see them in confinement, it would be difficult to name any
animals less restricted, by even a generic bar, in the gratification of the
sexual instinct. And although the conditions under which they have been
observed are abnormal, yet these are hardly the animals to present us in a
state of nature, with an extraordinary and exceptional sensitiveness in
such matters. [Page 192]
To take an altogether different case. Care of, and tenderness towards, the
aged and infirm are actions on all hands admitted to be "right;" but it is
difficult to see how such actions could ever have been so useful to a
community as to have been seized on and developed by the exclusive action
of the law of the "survival of the fittest." On the contrary, it seems
probable that on strict utilitarian principles the rigid political economy
of Tierra del Fuego would have been eminently favoured and diffused by the
impartial action of "Natural Selection" alone. By the rigid political
economy referred to, is meant that destruction and utilization of "useless
mouths" which Mr. Darwin himself describes in his highly interesting
"Journal of Researches."[207] He says: "It is certainly true, that when
pressed in winter by hunger, they kill and devour their old women before
they kill their dogs. The boy being asked why they did this, answered,
'Doggies catch otters, old women no.' They often run away into the
mountains, but they are pursued by the men and brought back to the
slaughter-house at their own firesides." Mr. Edward Bartlett, who has
recently returned from the Amazons, reports that at one Indian village
where the cholera made its appearance, the whole population immediately
dispersed into the woods, leaving the sick to perish uncared for and alone.
Now, had the Indians remained, undoubtedly far more would have died; as
doubtless, in Tierra del Fuego, the destruction of the comparatively
useless old women has often been the means of preserving the healthy and
reproductive young. Such acts surely must be greatly favoured by the stern
and unrelenting action of exclusive "Natural Selection."
In the same way that admiration which all feel for acts of self-denial done
for the good of others, and tending even towards the destruction of the
actor, could hardly be accounted for on Darwinian principles alone; for
self-immolators must but rarely leave direct descendants, while the
community they benefit must by their destruction tend, so far, to {193}
morally deteriorate. But devotion to others of the same community is by no
means _all_ that has to be accounted for. Devotion to the whole human race,
and devotion to God--in the form of asceticism--have been and are very
generally recognized as "good;" and the Author contends that it is simply
impossible to conceive that such ideas and sanctions should have been
developed by "Natural Selection" alone, from only that degree of
unselfishness necessary for the preservation of brutally barbarous
communities in the struggle for life. That degree of unselfishness once
attained, further improvement would be checked by the mutual opposition of
diverging moral tendencies and spontaneous variations in all directions.
Added to which, we have the principle of reversion and atavism, tending
powerfully to restore and reproduce that more degraded anterior condition
whence the later and better state painfully emerged.
Very few, however, dispute the complete distinctness, here and now, of the
ideas of "duty" and "interest" whatever may have been the origin of those
ideas. No one pretends that ingratitude may, in any past abyss of time,
have been a virtue, or that it may be such now in Arcturus or the Pleiades.
Indeed, a certain eminent writer of the utilitarian school of ethics has
amusingly and very instructively shown how radically distinct even in his
own mind are the two ideas which he nevertheless endeavours to identify.
Mr. John Stuart Mill, in his examination of "Sir William Hamilton's
Philosophy," says,[208] if "I am informed that the world is ruled by a
being whose attributes are infinite, but what they are we cannot learn, nor
what the principles of his government, except that 'the highest human
morality which we are capable of conceiving' does not sanction them;
convince me of it, and I will bear my fate as I may. But when I am told
that I must believe this, and at the same time call this being by the {194}
names which express and affirm the highest human morality, I say in plain
terms that I will not. Whatever power such a being may have over me, there
is one thing which he shall not do: he shall not compel me to worship him.
I will call no being good, who is not what I mean when I apply that epithet
to my fellow-creatures; and if such a being can sentence me to hell for not
so calling him, to hell I will go."
This is unquestionably an admirable sentiment on the part of Mr. Mill (with
which every absolute moralist will agree), but it contains a complete
refutation of his own position, and is a capital instance[209] of the
vigorous life of moral intuition in one who professes to have eliminated
any fundamental distinction between the "right" and the "expedient." For if
an action is morally good, and to be done, merely in proportion to the
amount of pleasure it secures, and morally bad and to be avoided as tending
to misery, and if it could be _proved_ that by calling God good--whether He
is so or not, in our sense of the term,--we could secure a maximum of
pleasure, and by refusing to do so we should incur endless torment,
clearly, on utilitarian principles, the flattery would be good.
Mr. Mill, of course, must also mean that, in the matter in question, all
men would do well to act with him. Therefore, he must mean that it would be
well for all to accept (on the hypothesis above given) infinite and final
misery for all as the result of the pursuit of happiness as the only end.
It must be recollected that in consenting to worship this unholy God, Mr.
Mill is not asked to do harm to his neighbour, so that his refusal reposes
simply on his perception of the immorality of the requisition. It is also
noteworthy that an omnipotent Deity is supposed incapable of altering Mr.
Mill's mind and moral perceptions.
Mr. Mill's decision is right, but it is difficult indeed to see how, {195}
without the recognition of an "absolute morality," he can justify so utter
and final an abandonment of all utility in favour of a clear and distinct
moral perception.
These two ideas, the "right" and the "useful," being so distinct here and
now, a greater difficulty meets us with regard to their origin from some
common source, than met us before when considering the first beginnings of
certain bodily structures. For the distinction between the "right" and the
"useful" is so fundamental and essential that not only does the idea of
benefit not enter into the idea of duty, but we see that the very fact of
an act _not_ being beneficial to us makes it the more praiseworthy, while
gain tends to diminish the merit of an action. Yet this idea, "right," thus
excluding, as it does, all reference to utility or pleasure, has
nevertheless to be constructed and evolved from utility and pleasure, and
ultimately from pleasurable sensations, if we are to accept pure
Darwinianism: if we are to accept, that is, the evolution of man's
psychical nature and highest powers, by the exclusive action of "Natural
Selection," from such faculties as are possessed by brutes; in other words,
if we are to believe that the conceptions of the highest human morality
arose through minute and fortuitous variations of brutal desires and
appetites in all conceivable directions.
It is here contended, on the other hand, that no conservation of any such
variations could ever have given rise to the faintest beginning of any such
moral perceptions; that by "Natural Selection" alone the maxim _fiat
justitia, ruat coelum_ could never have been excogitated, still less have
found a widespread acceptance; that it is impotent to suggest even an
approach towards an explanation of the _first beginning_ of the idea of
"right." It need hardly be remarked that acts may be distinguished not only
as pleasurable, useful, or beautiful, but also as good in two different
senses: (1) _materially_ moral acts, and (2) acts which are _formally_
moral. The first are acts good in themselves, _as acts_, apart from any
intention of the agent which may or may not have been directed towards{196}
"right." The second are acts which are good not only in themselves, as
acts, but also in the deliberate _intention_ of the agent who recognizes
his actions as being "right." Thus acts may be _materially_ moral or
immoral, in a very high degree, without being in the least _formally_ so.
For example, a person may tend and minister to a sick man with scrupulous
care and exactness, having in view all the time nothing but the future
reception of a good legacy. Another may, in the dark, shoot his own father,
taking him to be an assassin, and so commit what is _materially_ an act of
parricide, though _formally_ it is only an act of self-defence of more or
less culpable rashness. A woman may innocently, because ignorantly, marry a
married man, and so commit a _material_ act of adultery. She may discover
the facts, and persist, and so make her act _formal_ also.
Actions of brutes, such as those of the bee, the ant, or the beaver,
however materially good as regards their relation to the community to which
such animals belong, are absolutely destitute of the most incipient degree
of real, _i.e._ formal "goodness," because unaccompanied by mental acts of
conscious will directed towards the fulfilment of duty. Apology is due for
thus stating so elementary a distinction, but the statement is not
superfluous, for confusion of thought, resulting from confounding together
these very distinct things, is unfortunately far from uncommon.
Thus some Darwinians assert that the germs of morality exist in brutes, and
we have seen that Mr. Darwin himself speculates on the subject as regards
the highest apes. It may safely be affirmed, however, that there is no
trace in brutes of any actions simulating morality which are not explicable
by the fear of punishment, by the hope of pleasure, or by personal
affection. No sign of moral reprobation is given by any brute, and yet had
such existed in germ through Darwinian abysses of past time, some evidence
of its existence must surely have been rendered perceptible through
"survival of the fittest" in other forms besides man, if that {197}
"survival" has alone and exclusively produced it in him.
Abundant examples may, indeed, be brought forward of useful acts which
simulate morality, such as parental care of the young, &c. But did the most
undeviating habits guide all brutes in such matters, were even aged and
infirm members of a community of insects or birds carefully tended by young
which benefited by their experience, such acts would not indicate even the
faintest rudiment of real, _i.e._ formal, morality. "Natural Selection"
would, of course, often lead to the prevalence of acts beneficial to a
community, and to acts _materially_ good; but unless they can be shown to
be _formally_ so, they are not in the least to the point, they do not offer
any explanation of the origin of an altogether new and fundamentally
different motive and conception.
It is interesting, on the other hand, to note Mr. Darwin's statement as to
the existence of a distinct moral feeling, even in, perhaps, the very
lowest and most degraded of all the human races known to us. Thus in the
same "Journal of Researches"[210] before quoted, bearing witness to the
existence of moral reprobation on the part of the Fuegians, he says: "The
nearest approach to religious feeling which I heard of was shown by York
Minster (a Fuegian so named), who, when Mr. Bynoe shot some very young
ducklings as specimens, declared in the most solemn manner, 'Oh, Mr. Bynoe,
much rain, snow, blow much.' This was evidently a retributive punishment
for wasting human food."
Mr. Wallace gives the most interesting testimony, in his "Malay
Archipelago," to the existence of a very distinct, and in some instances
highly developed moral sense in the natives with whom he came in contact.
In one case,[211] a Papuan who had been paid in advance for bird-skins and
who had not been able to fulfil his contract before Mr. Wallace was on{198}
the point of starting, "came running down after us holding up a bird, and
saying with great satisfaction, 'Now I owe you nothing!'" And this though
he could have withheld payment with complete impunity.
Mr. Wallace's observations and opinions on this head seem hardly to meet
with due appreciation in Sir John Lubbock's recent work on Primitive
Man.[212] But considering the acute powers of observation and the industry
of Mr. Wallace, and especially considering the years he passed in familiar
and uninterrupted intercourse with natives, his opinion and testimony
should surely carry with it great weight. He has informed the Author that
he found a strongly marked and widely diffused modesty, in sexual matters,
amongst all the tribes with which he came in contact. In the same way Mr.
Bonwick, in his work on the Tasmanians, testifies to the modesty exhibited
by the naked females of that race, who by the decorum of their postures
gave evidence of the possession in germ of what under circumstances would
become the highest chastity and refinement.
Hasty and incomplete observations and inductions are prejudicial enough to
physical science, but when their effect is to degrade untruthfully our
common humanity, there is an additional motive to regret them. A hurried
visit to a tribe, whose language, traditions and customs are unknown, is
sometimes deemed sufficient for "smart" remarks as to "ape characters,"
&c., which are as untrue as irrelevant. It should not be forgotten how
extremely difficult it is to enter into the ideas and feelings of an alien
race. If in the nineteenth century a French theatrical audience can witness
with acquiescent approval, as a type of English manners and ideas, the
representation of a marquis who sells his wife at Smithfield, &c. &c., it
is surely no wonder if the ideas of a tribe of newly visited savages {199}
should be more or less misunderstood. To enter into such ideas requires
long and familiar intimacy, like that experienced by the explorer of the
Malay Archipelago. From him, and others, we have abundant evidence that
moral ideas exist, at least in germ, in savage races of men, while they
sometimes attain even a highly developed state. No amount of evidence as to
acts of moral depravity is to the point, as the object here aimed at is to
establish that moral intuitions _exist_ in savages, not that their actions
are good.
Objections, however, are sometimes drawn from the different notions as to
the moral value of certain acts, entertained by men of various countries or
of different epochs; also from the difficulty of knowing what particular
actions in certain cases are the right ones, and from the effects which
prejudice, interest, passion, habit, or even, indirectly, physical
conditions, may have upon our moral perceptions. Thus Sir John Lubbock
speaks[213] of certain Feejeeans, who, according to the testimony of Mr.
Hunt,[214] have the custom of piously choking their parents under certain
circumstances, in order to insure their happiness in a future life. Should
any one take such facts as telling _against_ the belief in an absolute
morality, he would show a complete misapprehension of the point in dispute;
for such facts tell in _favour_ of it.
Were it asserted that man possesses a distinct innate power and faculty by
which he is made intuitively aware what acts considered in and by
themselves are right and what wrong,--an infallible and universal internal
code,--the illustration would be to the point. But all that need be
contended for is that the intellect perceives not only truth, but also a
quality of "higher" which ought to be followed, and of "lower" which ought
to be avoided; when two lines of conduct are presented to the will for
choice, the intellect so acting being the conscience.
{200}
This has been well put by Mr. James Martineau in his excellent essay on
Whewell's Morality. He says,[215] "If moral good were a quality resident in
each action, as whiteness in snow, or sweetness in fruits; and if the moral
faculty was our appointed instrument for detecting its presence; many
consequences would ensue which are at variance with fact. The wide range of
differences observable in the ethical judgments of men would not exist; and
even if they did, could no more be reduced and modified by discussion than
constitutional differences of hearing or of vision. And, as the quality of
moral good either must or must not exist in every important operation of
the will, we should discern its presence or absence separately in each; and
even though we never had the conception of more than one insulated action,
we should be able to pronounce upon its character. This, however, we have
plainly no power to do. Every moral judgment is relative, and involves a
comparison of two terms. When we praise what _has been_ done, it is with
the coexistent conception of something _else_ that _might have been_ done;
and when we resolve on a course as right, it is to the exclusion of some
other that is wrong. This fact, that every ethical decision is in truth a
_preference_, an election of one act as higher than another, appears of
fundamental importance in the analysis of the moral sentiments."
From this point of view it is plain how trifling are arguments drawn from
the acts of a savage, since an action highly immoral in us might be one
exceedingly virtuous in him--being the highest presented to his choice in
his degraded intellectual condition and peculiar circumstances.
It need only be contended, then, that there _is_ a perception of "right"
incapable of further analysis; not that there is any infallible internal
guide as to all the complex actions which present themselves for {201}
choice. The _principle_ is given in our nature, the _application_ of the
principle is the result of a thousand educational influences.
It is no wonder, then, that, in complex "cases of conscience," it is
sometimes a matter of exceeding difficulty to determine which of two
courses of action is the less objectionable. This no more invalidates the
truth of moral principles than does the difficulty of a mathematical
problem cast doubt on mathematical principles. Habit, education, and
intellectual gifts facilitate the correct application of both.
Again, if our moral insight is intensified or blunted by our habitual
wishes or, indirectly, by our physical condition, the same may be said of
our perception of the true relations of physical facts one to another. An
eager wish for marriage has led many a man to exaggerate the powers of a
limited income, and a fit of dyspepsia has given an unreasonably gloomy
aspect to more than one balance-sheet.
Considering that moral intuitions have to do with _insensible_ matters,
they cannot be expected to be more clear than the perception of physical
facts. And if the latter perceptions may be influenced by volition, desire,
or health, our moral views may also be expected to be so influenced, and
this in a higher degree because they so often run counter to our desires. A
bottle or two of wine may make a sensible object appear double; what
wonder, then, if our moral perceptions are sometimes warped and distorted
by such powerful agencies as an evil education or an habitual absence of
self-restraint. In neither case does occasional distortion invalidate the
accuracy of normal and habitual perception.
The distinctness here and now of the ideas of "right" and "useful" is
however, as before said, fully conceded by Mr. Herbert Spencer, although he
contends that these conceptions are one in root and origin.
His utilitarian Genesis of Morals, however, has been recently combated{202}
by Mr. Richard Holt Hutton in a paper which appeared in _Macmillan's
Magazine_.[216]
This writer aptly objects an _argumentum ad hominem_, applying to morals
the same argument that has been applied in this work to our sense of
musical harmony, and by Mr. Wallace to the vocal organs of man.
Mr. Herbert Spencer's notions on the subject are thus expressed by himself:
"To make my position fully understood, it seems needful to add that,
corresponding to the fundamental propositions of a developed moral science,
there have been, and still are developing in the race certain fundamental
moral intuitions; and that, though these moral intuitions are the result of
accumulated experiences of utility gradually organized and inherited, they
have come to be quite independent of conscious experience. Just in the same
way that I believe the intuition of space possessed by any living
individual to have arisen from organized and consolidated experiences of
all antecedent individuals, who bequeathed to him their slowly developed
nervous organizations; just as I believe that this intuition, requiring
only to be made definite and complete by personal experiences, has
practically become a form of thought quite independent of experience;--so
do I believe that the experiences of utility, organized and consolidated
through all past generations of the human race, have been producing
corresponding nervous modifications which, by continued transmissions and
accumulation, have become in us certain faculties of moral intuition,
active emotions responding to right and wrong conduct, which have no
apparent basis in the individual experiences of utility. I also hold that,
just as the space intuition responds to the exact demonstrations of
geometry, and has its rough conclusions interpreted and verified by them,
so will moral intuitions respond to the demonstrations of moral science,
and will have their rough conclusions interpreted and verified by them."
{203}
Against this view of Mr. Herbert Spencer, Mr. Hutton objects--"1. That even
as regards Mr. Spencer's illustration from geometrical intuitions, his
process would be totally inadequate, since you could not deduce the
necessary space intuition of which he speaks from any possible
accumulations of familiarity with space relations.... We cannot _inherit_
more than our fathers _had_: no amount of experience of facts, however
universal, can give rise to that particular characteristic of intuitions
and _a priori_ ideas, which compels us to deny the possibility that in any
other world, however otherwise different, our experience (as to space
relations) could be otherwise.
"2. That the case of moral intuitions is very much stronger.
"3. That if Mr. Spencer's theory accounts for anything, it accounts not for
the deepening of a sense of utility and inutility into right and wrong, but
for the drying up of the sense of utility and inutility into mere inherent
tendencies, which would exercise over us not _more_ authority but _less_,
than a rational sense of utilitarian issues.
"4. That Mr. Spencer's theory could not account for the intuitional
sacredness now attached to _individual_ moral rules and principles, without
accounting _a fortiori_ for the general claim of the greatest happiness
principle over us as the final moral intuition---which is conspicuously
contrary to the fact, as not even the utilitarians themselves plead any
instinctive or intuitive sanction for their great principle.
"5. That there is no trace of positive evidence of any single instance of
the transformation of a utilitarian rule of right into an intuition, since
we find no utilitarian principle of the most ancient times which is now an
accepted moral intuition, nor any moral intuition, however sacred, which
has not been promulgated thousands of years ago, and which has not
constantly had to stop the tide of utilitarian _objections_ to its
authority--and this age after age, in our own day quite as much as in days
gone by.... Surely, if anything is remarkable in the history of {204}
morality, it is the _anticipatory_ character, if I may use the expression,
of moral principles--the intensity and absoluteness with which they are
laid down ages before the world has approximated to the ideal thus
asserted."
Sir John Lubbock, in his work on Primitive Man before referred to, abandons
Mr. Spencer's explanation of the genesis of morals while referring to Mr.
Hutton's criticisms on the subject. Sir John proposes to substitute
"deference to authority" instead of "sense of interest" as the origin of
our conception of "duty," saying that what has been found to be beneficial
has been traditionally inculcated on the young, and thus has become to be
dissociated from "interest" in the mind, though the inculcation itself
originally sprung from that source. This, however, when analysed, turns out
to be a distinction without a difference. It is nothing but utilitarianism,
pure and simple, after all. For it can never be intended that authority is
obeyed because of an intuition that it _should be deferred to_, for that
would be to admit the very principle of absolute morality which Sir John
combats. It must be meant, then, that authority is obeyed through fear of
the consequences of disobedience, or through pleasure felt in obeying the
authority which commands. In the latter case we have "pleasure" as the end
and no rudiment of the conception "duty." In the former we have fear of
punishment, which appeals directly to the sense of "utility to the
individual," and no amount of such a sense will produce the least germ of
"ought" which is a conception different _in kind_, and in which the notion
of "punishment" has no place. Thus, Sir John Lubbock's explanation only
concerns a _mode_ in which the sense of "duty" may be stimulated or
appealed to, and makes no approximation to an explanation of its origin.
Could the views of Mr. Herbert Spencer, of Mr. Mill, or of Mr. Darwin on
this subject be maintained, or should they come to be generally accepted,
the consequences would be disastrous indeed! Were it really the case that
virtue was a _mere kind of "retrieving,"_ then certainly we should {205}
have to view with apprehension the spread of intellectual cultivation,
which would lead the human "retrievers" to regard from a new point of view
their fetching and carrying. We should be logically compelled to acquiesce
in the vociferations of some continental utilitarians, who would banish
altogether the senseless words "duty" and "merit;" and then, one important
influence which has aided human progress being withdrawn, we should be
reduced to hope that in this case the maxim _cessante causa cessat ipse
effectus_ might through some incalculable accident fail to apply.
It is true that Mr. Spencer tries to erect a safeguard against such moral
disruption, by asserting that for every immoral act, word, or thought, each
man during this life receives minute and exact retribution, and that thus a
regard for individual self-interest will effectually prevent any moral
catastrophe. But by what means will he enforce the acceptance of a dogma
which is not only incapable of proof, but is opposed to the commonly
received opinion of mankind in all ages? Ancient literature, sacred and
profane, teems with protests against the successful evil-doer, and
certainly, as Mr. Hutton observes,[217] "Honesty must have been associated
by our ancestors with many unhappy as well as many happy consequences, and
we know that in ancient Greece dishonesty was openly and actually
associated with happy consequences.... When the concentrated experience of
previous generations was held, _not_ indeed to justify, but to excuse by
utilitarian considerations, craft, dissimulation, sensuality, selfishness."
This dogma is opposed to the moral consciousness of many as to the events
of their own lives; and the Author, for one, believes that it is absolutely
contrary to fact.
History affords multitudes of instances, but an example may be selected
from one of the most critical periods of modern times. Let it be {206}
granted that Lewis the Sixteenth of France and his queen had all the
defects attributed to them by the most hostile of serious historians; let
all the excuses possible be made for his predecessor, Lewis the Fifteenth,
and also for Madame de Pompadour, can it be pretended that there are
grounds for affirming that the vices of the two former so far exceeded
those of the latter, that their respective fates were plainly and evidently
just? that while the two former died in their beds, after a life of the
most extreme luxury, the others merited to stand forth through coming time
as examples of the most appalling and calamitous tragedy?
This theme, however, is too foreign to the immediate matter in hand to be
further pursued, tempting as it is. But a passing protest against a
superstitious and deluding dogma may stand,--a dogma which may, like any
other dogma, be vehemently asserted and maintained, but which is remarkable
for being destitute, at one and the same time, of both authoritative
sanction and the support of reason and observation.
To return to the bearing of moral conceptions on "Natural Selection," it
seems that, from the reasons given in this chapter, we may safely
affirm--1. That "Natural Selection" could not have produced, from the
sensations of pleasure and pain experienced by brutes, a higher degree of
morality than was useful; therefore it could have produced any amount of
"beneficial habits," but not abhorrence of certain acts as impure and
sinful.
2. That it could not have developed that high esteem for acts of care and
tenderness to the aged and infirm which actually exists, but would rather
have perpetuated certain low social conditions which obtain in some savage
localities.
3. That it could not have evolved from ape sensations the noble virtue of a
Marcus Aurelius, or the loving but manly devotion of a St. Lewis.
4. That, alone, it could not have given rise to the maxim _fiat justitia,
ruat coelum_. [Page 207]
5. That the interval between material and formal morality is one altogether
beyond its power to traverse.
Also, that the anticipatory character of moral principles is a fatal bar to
that explanation of their origin which is offered to us by Mr. Herbert
Spencer. And, finally, that the solution of that origin proposed recently
by Sir John Lubbock is a mere version of simple utilitarianism, appealing
to the pleasure or safety of the individual, and therefore utterly
incapable of solving the riddle it attacks.
Such appearing to be the case as to the power of "Natural Selection," we,
nevertheless, find moral conceptions--_formally_ moral ideas--not only
spread over the civilized world, but manifesting themselves unmistakeably
(in however rudimentary a condition, and however misapplied) amongst the
lowest and most degraded of savages. If from amongst these, individuals can
be brought forward who seem to be destitute of any moral conception,
similar cases also may easily be found in highly civilized communities.
Such cases tell no more against moral intuitions than do cases of
colour-blindness or idiotism tell against sight and reason. We have thus a
most important and conspicuous fact, the existence of which is fatal to the
theory of "Natural Selection," as put forward of late by Mr. Darwin and his
most ardent followers. It must be remarked, however, that whatever force
this fact may have against a belief in the origination of man from brutes
by minute, fortuitous variations, it has no force whatever against the
conception of the orderly evolution and successive manifestation of
specific forms by ordinary natural law--even if we include amongst such the
upright frame, the ready hand and massive brain of man himself. [Page 208]
* * * * *
CHAPTER X.
PANGENESIS.
A provisional hypothesis supplementing "Natural Selection."--Statement
of the hypothesis.--Difficulty as to multitude of gemmules.--As to
certain modes of reproduction.--As to formations without the requisite
gemmules.--Mr. Lewes and Professor Delpino.--Difficulty as to
developmental force of gemmules.--As to their spontaneous
fission.--Pangenesis and Vitalism.--Paradoxical reality.--Pangenesis
scarcely superior to anterior hypotheses.--Buffon.--Owen.--Herbert
Spencer.--"Gemmules" as mysterious as "physiological
units."--Conclusion.
In addition to the theory of "Natural Selection," by which it has been
attempted to account for the origin of species, Mr. Darwin has also put
forward what he modestly terms "a provisional hypothesis" (that of
_Pangenesis_), by which to account for the origin of each and every
individual form.
Now, though the hypothesis of Pangenesis is no necessary part of "Natural
Selection," still any treatise on specific origination would be incomplete
if it did not take into consideration this last speculation of Mr. Darwin.
The hypothesis in question may be stated as follows: That each living
organism is ultimately made up of an almost infinite number of minute
particles, or organic atoms, termed "gemmules," each of which has the power
of reproducing its kind. Moreover, that these particles circulate freely
about the organism which is made up of them, and are derived from all the
parts of all the organs of the less remote ancestors of each such {209}
organism during all the states and stages of such several ancestors'
existence; and therefore of the several states of each of such ancestors'
organs. That such a complete collection of gemmules is aggregated in each
ovum and spermatozoon in most animals, and in each part capable of
reproducing by gemmation (budding) in the lowest animals and in plants.
Therefore in many of such lower organisms such a congeries of ancestral
gemmules must exist in every part of their bodies, since in them every part
is capable of reproducing by gemmation. Mr. Darwin must evidently admit
this, since he says: "It has often been said by naturalists that each cell
of a plant has the actual or potential capacity of reproducing the whole
plant; but it has this power only in virtue of containing gemmules _derived
from every part_."[218]
Moreover, these gemmules are supposed to tend to aggregate themselves, and
to reproduce in certain definite relations to other gemmules. Thus, when
the foot of an eft is cut off, its reproduction is explained by Mr. Darwin
as resulting from the aggregation of those floating gemmules which come
next in order to those of the cut surface, and the successive aggregations
of the other kinds of gemmules which come after in regular order. Also, the
most ordinary processes of repair are similarly accounted for, and the
successive development of similar parts and organs in creatures in which
such complex evolutions occur is explained in the same way, by the
independent action of separate gemmules.
In order that each living creature may be thus furnished, the number of
such gemmules in each must be inconceivably great. Mr. Darwin says:[219]
"In a highly organized and complex animal, the gemmules thrown off from
each different cell or unit throughout the body must be inconceivably
numerous and minute. Each unit of each part, as it changes during
development--and we know that some insects undergo at least twenty {210}
metamorphoses--must throw off its gemmules. All organic beings, moreover,
include many dormant gemmules derived from their grandparents and more
remote progenitors, but not from all their progenitors. These _almost
infinitely numerous_ and minute gemmules must be included in each bud,
ovule, spermatozoon, and pollen grain." We have seen also that in certain
cases a similar multitude of gemmules must be included also in every
considerable part of the whole body of each organism, but where are we to
stop? There must be gemmules not only from every organ, but from every
component part of such organ, from every subdivision of such component
part, and from every cell, thread, or fibre entering into the composition
of such subdivision. Moreover, not only from all these, but from each and
every successive stage of the evolution and development of such
successively more and more elementary parts. At the first glance this new
atomic theory has charms from its apparent simplicity, but the attempt thus
to follow it out into its ultimate limits and extreme consequences seems to
indicate that it is at once insufficient and cumbrous.
Mr. Darwin himself is, of course, fully aware that there must be _some_
limit to this aggregation of gemmules. He says:[220] "Excessively minute
and numerous as they are believed to be, an infinite number derived, during
a long course of modification and descent, from each cell of each
progenitor, could not be supported and nourished by the organism."
But apart from these matters, which will be more fully considered further
on, the hypothesis not only does not appear to account for certain
phenomena which, in order to be a valid theory, it ought to account for;
but it seems absolutely to conflict with patent and notorious facts.
How, for example, does it explain the peculiar reproduction which is {211}
found to take place in certain marine worms--certain annelids?
[Illustration: AN ANNELID DIVIDING SPONTANEOUSLY.
(A new head having been formed towards the hinder end of the body of the
parent.)]
In such creatures we see that, from time to time, one of the segments of
the body gradually becomes modified till it assumes the condition of a
head, and this remarkable phenomenon is repeated again and again, the body
of the worm thus multiplying serially into new individuals which
successively detach themselves from the older portion. The development of
such a mode of reproduction by "Natural Selection" seems not less
inexplicable than does its continued performance through the aid of {212}
"pangenesis." For how can gemmules attach themselves to others to which
they do not normally or generally succeed? Scarcely less difficult to
understand is the process of the stomach-carrying-off mode of metamorphosis
before spoken of as existing in the Echinoderms. Next, as to certain patent
and notorious facts: On the hypothesis of pangenesis, no creature can
develop an organ unless it possesses the component gemmules which serve for
its formation. No creature can possess such gemmules unless it inherits
them from its parents, grandparents, or its less remote ancestors. Now, the
Jews are remarkably scrupulous as to marriage, and rarely contract such a
union with individuals not of their own race. This practice has gone on for
thousands of years, and similarly also for thousands of years the rite of
circumcision has been unfailingly and carefully performed. If then the
hypothesis of pangenesis is well founded, that rite ought to be now
absolutely or nearly superfluous from the necessarily continuous absence of
certain gemmules through so many centuries and so many generations. Yet it
is not at all so, and this fact seems to amount almost to an experimental
demonstration that the hypothesis of pangenesis is an insufficient
explanation of individual evolution.
Two exceedingly good criticisms of Mr. Darwin's hypothesis have appeared.
One of these is by Mr. G. H. Lewes,[221] the other by Professor Delpino of
Florence.[222] The latter gentleman gives a report of an observation made
by him upon a certain plant, which observation adds force to what has just
been said about the Jewish race. He says:[223] "If we examine and compare
the numerous species of the genus _Salvia_, commencing with _Salvia
officinalis_, which may pass as the main state of the genus, and {213}
concluding with _Salvia verticillata_, which may be taken as the most
highly developed form, and as the most distant from the type, we observe a
singular phenomenon. The lower cell of each of the two fertile anthers,
which is much reduced and different from the superior even in _Salvia
officinalis_, is transmuted in other _salviæ_ into an organ (nectarotheca)
having a very different form and function, and finally disappears entirely
in _Salvia verticillata_.
"Now, on one occasion, in a flower belonging to an individual of _Salvia
verticillata_, and only on the left stamen, I observed a perfectly
developed and pollinigerous lower cell, perfectly homologous with that
which is normally developed in _Salvia officinalis_. This case of atavism
is truly singular. According to the theory of Pangenesis, it is necessary
to assume that all the gemmules of this anomalous formation, and therefore
the mother-gemmule of the cell, and the daughter-gemmules of the special
epidermic tissue, and of the very singular subjacent tissue of the
endothecium, have been perpetuated, and transmitted from parent to
offspring in a dormant state, and through a number of generations, such as
startles the imagination, and leads it to refuse its consent to the theory
of Pangenesis, however seductive it may be." This seems a strong
confirmation of what has been here advanced.
The main objection raised against Mr. Darwin's hypothesis is that it
(Pangenesis) requires so many subordinate hypotheses for its support, and
that some of these are not tenable.
Professor Delpino considers[224] that as many as eight of these subordinate
hypotheses are required, namely, that--
"1. The emission of the gemmules takes place, or may take place in all
states of the cell.
"2. The quantity of gemmules emitted from every cell is very great.
"3. The minuteness of the gemmules is extreme.
{214}
"4. The gemmules possess two sorts of affinity, one of which might be
called _propagative_, and the other _germinative_ affinity.
"5. By means of the propagative affinity all the gemmules emitted by all
the cells of the individual flow together and become condensed in the cells
which compose the sexual organs, whether male or female (embryonal vesicle,
cells of the embryo, pollen grains, fovilla, antherozoids, spermatozoids),
and likewise flow together and become condensed in the cells which
constitute the organs of a sexual or agamic reproduction (buds, spores,
bulbilli, portions of the body separated by scission, &c.).
"6. By means of the germinative affinity, every gemmule (except in cases of
anomalies or monstrosities) can be developed only in cells homologous with
the mother-cells of the cell from which they originated. In other words,
the gemmules from any cell can only be developed in unison with the cell
preceding it in due order of succession, and whilst in a nascent state.
"7. Of each kind of gernmule a great number perishes; a great number
remains in a dormant state through many generations in the bodies of
descendants; the remainder germinate and reproduce the mother-cell.
"8. Every gemmule may multiply itself by a process of scission into any
number of equivalent gemmules."
Mr. Darwin has published a short notice in reply to Professor Delpino, in
_Scientific Opinion_ of October 20, 1869, p. 426. In this reply he admits
the justice of Professor Delpino's attack, but objects to the alleged
necessity of the first subordinate hypothesis, namely, that the emission of
gemmules takes place in all states of the cell. But if this is not the
case, then a great part of the utility and distinction of pangenesis is
destroyed, or as Mr. Lewes justly says,[225] "If gemmules produce whole
cells, we have the very power which was pronounced mysterious in larger
organisms."
{215}
Mr. Darwin also does not see the force of the objection to the power of
self-division which must be asserted of the gemmules themselves if
Pangenesis be true. The objection, however, appears to many to be
formidable. To admit the power of spontaneous division and multiplication
in such rudimentary structures, seems a complete contradiction. The
gemmules, by the hypothesis of Pangenesis, are the ultimate organized
components of the body, the absolute organic atoms of which each body is
composed; how then _can_ they be divisible? Any part of a gemmule would be
an impossible (because a _less_ than possible) quantity. If it is divisible
into still smaller organic wholes, as a germ-cell is, it must be made up as
the germ-cell is, of subordinate component atoms, which are then the _true_
gemmules. This process may be repeated _ad infinitum_, unless we get to
true organic atoms, the true gemmules, whatever they may be, and they
necessarily will be incapable of any process of spontaneous fission. It is
remarkable that Mr. Darwin brings forward in support of gemmule fission,
the observation that "Thuret has seen the zoospore of an alga divide
itself, and both halves germinate." Yet on the hypothesis of Pangenesis,
the zoospore of an alga must contain gemmules from all the cells of the
parent algæ, and from all the parts of all their less remote ancestors in
all their stages of existence. What wonder then that such an excessively
complex body should divide and multiply; and what parity is there between
such a body and a gemmule? A steam-engine and a steel-filing might equally
well be compared together.
Professor Delpino makes a further objection which, however, will only be of
weight in the eyes of Vitalists. He says,[226] Pangenesis is not to be
received because "it leads directly to the negation of a specific vital
principle, co-ordinating and regulating all the movements, acts, and
functions of the individuals in which it is incarnated. For Pangenesis of
the individual is a term without meaning. If, in contemplating an {216}
animal of high organization, we regard it purely as an aggregation of
developed gemmules, although these gemmules have been evolved successively
one after the other, and one within the other, notwithstanding they elude
the conception of the _real and true individual_, these problematical and
invisible gemmules must be regarded as so many individuals. Now, that real,
true, living individuals exist in nature, is a truth which is persistently
attested to us by our consciousness. But how, then, can we explain that a
great quantity of dissimilar elements, like the atoms of matter, can unite
to form those perfect unities which we call individuals, if we do not
suppose the existence of a specific principle, proper to the individual but
foreign to the component atoms, which aggregates these said atoms, groups
them into molecules, and then moulds the molecules into cells, the cells
into tissues, the tissues into organs, and the organs into apparatus?"
"But, it may be urged in opposition by the Pangenesists, your vital
principle is an unknown and irresolute _x_. This is true; but, on the other
hand, let us see whether Pangenesis produces a clearer formula, and one
free from unknown elements. The existence of the gemmules is a first
unknown element; the propagative affinity of the gemmules is a second;
their germinative affinity is a third; their multiplication by fission is a
fourth--and what an unknown element!"
"Thus, in Pangenesis, everything proceeds by force of unknown elements, and
we may ask whether it is more logical to prefer a system which assumes a
multitude of unknown elements to a system which assumes only a single one?"
Mr. Darwin appears, by "Natural Selection," to destroy the reality of
species, and by Pangenesis that of the individual. Mr. Lewes observes[227]
of the individual that "This whole is only a subjective conception which
summarizes the parts, and that in point of fact it is the parts which {217}
are reproduced." But the parts are also, from the same point of view,
merely subjective until we come to the absolute organic atoms. These atoms,
on the other hand, are utterly invisible, intangible; indeed, in the words
of Mr. Darwin, inconceivable. Thus, then, it results from the theories in
question, that the organic world is reduced to utter unreality as regards
all that can be perceived by the senses or distinctly imagined by the mind;
while the only reality consists of the invisible, the insensible, the
inconceivable; in other words, nothing is known that really is, and only
the nonexistent can be known. A somewhat paradoxical outcome of the
speculations of those who profess to rely exclusively on the testimony of
sense. "_Les extrêmes se touchent_," and extreme sensationalism shakes
hands with the "das seyn ist das nichts" of Hegel.
Altogether the hypothesis of Pangenesis seems to be little, if at all,
superior to anterior hypotheses of a more or less similar nature.
Apart from the atoms of Democritus, and apart also from the speculations of
mediæval writers, the molecules of Bonnet and of Buffon almost anticipated
the hypothesis of Pangenesis. According to the last-named author,[228]
organic particles from every part of the body assemble in the sexual
secretions, and by their union build up the embryo, each particle taking
its due place, and occupying in the offspring a similar position to that
which it occupied in the parents. In 1849 Professor Owen, in his treatise
on "Parthenogenesis," put forward another conception. According to this,
the cells resulting from the subdivision of the germ-cell preserve their
developmental force, unless employed in building up definite organic
structures. In certain creatures, and in certain parts of other creatures,
germ-cells unused are stored up, and by their agency lost limbs and {218}
other mutilations are repaired. Such unused products of the germ-cell are
also supposed to become located in the generative products.
According to Mr. Herbert Spencer, in his "Principles of Biology," each
living organism consists of certain so-called "physiological units." Each
of these units has an innate power and capacity, by which it tends to build
up and reproduce the entire organism of which it forms a part, unless in
the meantime its force is exhausted by its taking part in the production of
some distinct and definite tissue--a condition somewhat similar to that
conceived by Professor Owen.
Now, at first sight, Mr. Darwin's atomic theory appears to be more simple
than any of the others. It has been objected that while Mr. Spencer's
theory requires the assumption of an innate power and tendency in each
physiological unit, Mr. Darwin's, on the other hand, requires nothing of
the kind, but explains the evolution of each individual by purely
mechanical conceptions. In fact, however, it is not so. Each gemmule,
according to Mr. Darwin, is really the seat of powers, elective affinities,
and special tendencies as marked and mysterious as those possessed by the
physiological unit of Mr. Spencer, with the single exception that the
former has no tendency to build up the whole living, complex organism of
which it forms a part. Some may think this an important distinction, but it
can hardly be so, for Mr. Darwin considers that his gemmule has the innate
power and tendency to build up and transform itself into the whole living,
complex cell of which it forms a part; and the one tendency is, in
principle, fully as difficult to understand, fully as mysterious, as is the
other. The difference is but one of degree, not of kind. Moreover, the one
mystery in the case of the "physiological unit" explains all, while with
regard to the gemmule, as we have seen, it has to be supplemented by other
powers and tendencies, each distinct, and each in itself inexplicable and
profoundly mysterious. [Page 219]
That there should be physiological units possessed of the power attributed
to them, harmonizes with what has recently been put forward by Dr. H.
Charlton Bastian; who maintains that under fit conditions the simplest
organisms develop themselves into relatively large and complex ones. This
is not supposed by him to be due to any inheritance of ancestral gemmules,
but to direct growth and transformation of the most minute and the simplest
organisms, which themselves, by all reason and analogy, owe their existence
to immediate transformation from the inorganic world.
Thus, then, there are grave difficulties in the way of the reception of the
hypothesis of Pangenesis, which moreover, if established, would leave the
evolution of individual organisms, when thoroughly analysed, little if at
all less mysterious or really explicable than it is at present.
As was said at the beginning of this chapter, "Pangenesis" and "Natural
Selection" are quite separable and distinct hypotheses. The fall of one of
these by no means necessarily includes that of the other. Nevertheless, Mr.
Darwin has associated them closely together, and, therefore, the refutation
of Pangenesis may render it advisable for those who have hitherto accepted
"Natural Selection" to reconsider that theory. [Page 220]
* * * * *
CHAPTER XI.
SPECIFIC GENESIS.
Review of the statements and arguments of preceding
chapters.--Cumulative argument against predominant action of "Natural
Selection."--Whether anything positive as well as negative can be
enunciated.--Constancy of laws of nature does not necessarily imply
constancy of specific evolution.--Possible exceptional stability of
existing epoch.--Probability that an internal cause of change
exists.--Innate powers must be conceived as existing somewhere or
other.--Symbolism of molecular action under vibrating
impulses.--Professor Owen's statement.--Statement of the Author's
view.--It avoids the difficulties which oppose "Natural Selection."--It
harmonizes apparently conflicting conceptions.--Summary and conclusion.
Having now severally reviewed the principal biological facts which bear
upon specific manifestation, it remains to sum up the results, and to
endeavour to ascertain what, if anything, can be said _positively_, as well
as negatively, on this deeply interesting question.
In the preceding chapters it has been contended, in the first place, that
no mere survival of the fittest accidental and minute variations can
account for the incipient stages of useful structures, such as, _e.g._, the
heads of flat-fishes, the baleen of whales, vertebrate limbs, the laryngeal
structures of the newborn kangaroo, the pedicellariæ of Echinoderms, or for
many of the facts of mimicry, and especially those last touches of mimetic
perfection, where an insect not only mimics a leaf, but one worm-eaten and
attacked by fungi. [Page 221]
Also, that structures like the hood of the cobra and the rattle of the
rattlesnake seem to require another explanation.
Again, it has been contended that instances of colour, as in some apes; of
beauty, as in some shell-fish; and of utility, as in many orchids, are
examples of conditions which are quite beyond the power of Natural
Selection to originate and develop.
Next, the peculiar mode of origin of the eye (by the simultaneous and
concurrent modification of distinct parts), with the wonderful refinement
of the human ear and voice, have been insisted on; as also, that the
importance of all these facts is intensified through the necessity
(admitted by Mr. Darwin) that many individuals should be similarly and
simultaneously modified in order that slightly favourable variations may
hold their own in the struggle for life, against the overwhelming force and
influence of mere number.
Again, we have considered, in the third chapter, the great improbability
that from minute variations in all directions alone and unaided, save by
the survival of the fittest, closely similar structures should
independently arise; though, on a non-Darwinian evolutionary hypothesis,
their development might be expected _a priori_. We have seen, however, that
there are many instances of wonderfully close similarity which are not due
to genetic affinity; the most notable instance, perhaps, being that brought
forward by Mr. Murphy, namely, the appearance of the same eye-structure in
the vertebrate and molluscous sub-kingdoms. A curious resemblance, though
less in degree, has also been seen to exist between the auditory organs of
fishes and of Cephalopods. Remarkable similarities between certain
placental and implacental mammals, between the bird's-head processes of
Polyzoa and the pedicellariæ of Echinoderms, between Ichthyosauria and
Cetacea, with very many other similar coincidences, have also been pointed
out.
Evidence has also been brought forward to show that similarity is sometimes
directly induced by very obscure conditions, at present quite {222}
inexplicable, _e.g._ by causes immediately connected with geographical
distribution; as in the loss of the tail in certain forms of Lepidoptera
and in simultaneous modifications of colour in others, and in the direct
modification of young English oysters, when transported to the shore of the
Mediterranean.
Again, it has been asserted that certain groups of organic forms seem to
have an innate tendency to remarkable developments of some particular kind,
as beauty and singularity of plumage in the group of birds of paradise.
It has also been contended that there is something to be said in favour of
sudden, as opposed to exceedingly minute and gradual, modifications, even
if the latter are not fortuitous. Cases were brought forward, in Chapter
IV., such as the bivalve just mentioned, twenty-seven kinds of American
trees simultaneously and similarly modified, also the independent
production of pony breeds, and the case of the English greyhounds in
Mexico, the offspring of which produced directly acclimated progeny.
Besides these, the case of the Normandy pigs, of _Datura tatula_, and also
of the black-shouldered peacock, have been spoken of. The teeth of the
labyrinthodon, the hand of the potto, the whalebone of whales, the wings of
birds, the climbing tendrils of some plants, &c. have also been adduced as
instances of structures, the origin and production of which are probably
due rather to considerable modifications than to minute increments.
It has also been shown that certain forms which were once supposed to be
especially transitional and intermediate (as, _e.g._, the aye-aye) are
really by no means so; while the general rule, that the progress of forms
has been "from the more general to the more special," has been shown to
present remarkable exceptions, as, _e.g._, Macrauchenia, the Glyptodon, and
the sabre-toothed tiger (Machairodus).
Next, as to specific stability, it has been seen that there may be a {223}
certain limit to normal variability, and that if changes take place they
may be expected _a priori_ to be marked and considerable ones, from the
facts of the inorganic world, and perhaps also of the lowest forms of the
organic world. It has also been seen that with regard to minute spontaneous
variations in races, there is a rapidly increasing difficulty in
intensifying them, in any one direction, by ever such careful breeding.
Moreover, it has appeared that different species show a tendency to
variability in special directions, and probably in different degrees, and
that at any rate Mr. Darwin himself concedes the existence of an internal
barrier to change when he credits the goose with "a singularly inflexible
organization;" also, that he admits the presence of an _internal_
proclivity to change when he speaks of "a whole organization seeming to
have become plastic, and tending to depart from the parental type."
We have seen also that a marked tendency to reversion does exist, inasmuch
as it sometimes takes place in a striking manner, as exemplified in the
white silk fowl in England, _in spite of_ careful selection in breeding.
Again, we have seen that a tendency exists in nature to eliminate hybrid
races, by whatever means that elimination is effected, while no similar
tendency bars the way to an indefinite blending of varieties. This has also
been enforced by statements as to the prepotency of certain pollen of
identical species, but of distinct races.
To all the preceding considerations have been added others derived from the
relations of species to past time. It has been contended that we have as
yet no evidence of minutely intermediate forms connecting uninterruptedly
together undoubtedly distinct species. That while even "horse ancestry"
fails to supply such a desideratum, in very strongly marked and exceptional
kinds (such as the Ichthyosauria, Chelonia, and Anoura), the absence of
links is very important and significant. For if every species, without{224}
exception, has arisen by minute modifications, it seems incredible that a
small percentage of such transitional forms should not have been preserved.
This, of course, is especially the case as regards the marine Ichthyosauria
and Plesiosauria, of which such numbers of remains have been discovered.
Sir William Thomson's great authority has been seen to oppose itself to
"Natural Selection," by limiting, on astronomical and physical grounds, the
duration of life on this planet to about one hundred million years. This
period, it has been contended, is not nearly enough on the one hand for the
evolution of all organic forms by the exclusive action of mere minute,
fortuitous variations; on the other hand, for the deposition of all the
strata which must have been deposited, if minute fortuitous variation was
the manner of successive specific manifestation.
Again, the geographical distribution of existing animals has been seen to
present difficulties which, though not themselves insurmountable, yet have
a certain weight when taken in conjunction with all the other objections.
The facts of homology, serial, bilateral and vertical, have also been
passed in review. Such facts, it has been contended, are not explicable
without admitting the action of what may most conveniently be spoken of as
an _internal_ power, the existence of which is supported by facts not only
of comparative anatomy but of teratology and pathology also. "Natural
Selection" also has been shown to be impotent to explain these phenomena,
while the existence of such an internal power of homologous evolution
diminishes the _a priori_ improbability of an analogous law of specific
origination.
All these various considerations have been supplemented by an endeavour to
show the utter inadequacy of Mr. Darwin's theory with regard to the higher
psychical phenomena of man (especially the evolution of moral conceptions),
and with regard to the evolution of individual organisms by the action{225}
of Pangenesis. And it was implied that if Mr. Darwin's latter hypothesis
can be shown to be untenable, an antecedent doubt is thus thrown upon his
other conception, namely, the theory of "Natural Selection."
A cumulative argument thus arises against the prevalent action of "Natural
Selection," which, to the mind of the Author, is conclusive. As before
observed, he was not originally disposed to reject Mr. Darwin's fascinating
theory. Reiterate endeavours to solve its difficulties have, however, had
the effect of convincing him that that theory as the one or as the leading
explanation of the successive evolution and manifestation of specific
forms, is untenable. At the same time he admits fully that "Natural
Selection" acts and must act, and that it plays in the organic world a
certain though a secondary and subordinate part.
The one _modus operandi_ yet suggested having been found insufficient, the
question arises, Can another be substituted in its place? If not, can
anything that is positive, and if anything, what, be said as to the
question of specific origination?
Now, in the first place, it is of course axiomatic that the laws which
conditioned the evolution of extinct and of existing species are of as much
efficacy at this moment as at any preceding period, that they _tend_ to the
manifestation of new forms as much now as ever before. It by no means
necessarily follows, however, that this tendency is actually being carried
into effect, and that new species of the higher animals and plants are
actually now produced. They may be so or they may not, according as
existing circumstances favour, or conflict with, the action of those laws.
It is possible that lowly organized creatures may be continually evolved at
the present day, the requisite conditions being more or less easily
supplied. There is, however, no similar evidence at present as to higher
forms; while, as we have seen in Chapter VII., there are _a priori_
considerations which militate against their being similarly evolved. {226}
The presence of wild varieties and the difficulty which often exists in the
determination of species are sometimes adduced as arguments that high forms
are now in process of evolution. These facts, however, do not necessarily
prove more than that some species possess a greater variability than
others, and (what is indeed unquestionable) that species have often been
unduly multiplied by geologists and botanists. It may be, for example, that
Wagner was right, and that all the American monkeys of the genus cebus may
be reduced to a single species or to two.
With regard to the lower organisms, and supposing views recently advanced
to become fully established, there is no reason to think that the forms
said to be evolved were new species, but rather reappearances of definite
kinds which had appeared before and will appear again under the same
conditions. In the same way, with higher forms similar conditions must
educe similar results, but here practically similar conditions can rarely
obtain because of the large part which "descent" and "inheritance" always
play in such highly organized forms.
Still it is conceivable that different combinations at different times may
have occasionally the same outcome just as the multiplications of different
numbers may have severally the same result.
There are reasons, however, for thinking it possible that the human race is
a witness of an exceptionally unchanging and stable condition of things, if
the calculations of Mr. Croll are valid as to how far variations in the
eccentricity in the earth's orbit together with the precession of the
equinoxes have produced changes in climate. Mr. Wallace has pointed
out[229] that the last 60,000 years having been exceptionally unchanging as
regards these conditions, specific evolution may have been {227}
exceptionally rare. It becomes then possible to suppose that for a similar
period stimuli to change in the manifestation of animal forms may have been
exceptionally few and feeble,--that is, if the conditions of the earth's
orbit have been as exceptional as stated. However, even if new species are
actually now being evolved as actively as ever, or if they have been so
quite recently, no conflict thence necessarily arises with the view here
advocated. For it by no means follows that if some examples of new species
have recently been suddenly produced from individuals of antecedent
species, we ought to be able to put our fingers on such cases; as Mr.
Murphy well observes[230] in a passage before quoted, "If a species were to
come suddenly into being in the wild state, as the Ancon sheep did under
domestication, how could we ascertain the fact? If the first of a
newly-born species were found, the fact of its discovery would tell nothing
about its origin. Naturalists would register it as a very rare species,
having been only once met with, but they would have no means of knowing
whether it were the first or the last of its race."
But are there any grounds for thinking that in the genesis of species an
_internal_ force or tendency interferes, co-operates with and controls the
action of external conditions?
It is here contended that there are such grounds, and that though
inheritance, reversion, atavism, Natural Selection, &c., play a part not
unimportant, yet that such an internal power is a great, perhaps the main,
determining agent.
It will, however, be replied that such an entity is no _vera causa_; that
if the conception is accepted, it is no real explanation; and that it is
merely a roundabout way of saying that the facts are as they are, while the
cause remains unknown. To this it may be rejoined that for all who believe
in the existence of the abstraction "force" at all, other than will, {228}
this conception of an internal force must be accepted and located
somewhere--cannot be eliminated altogether; and that therefore it may as
reasonably be accepted in this mode as in any other.
It was urged at the end of the third chapter that it is congruous to credit
mineral species with an internal power or force. By such a power it may be
conceived that crystals not only assume their external symmetry, but even
repair it when injured. Ultimate chemical elements must also be conceived
as possessing an innate tendency to form certain unions, and to cohere in
stable aggregations. This was considered towards the end of Chapter VIII.
Turning to the organic world, even on the hypothesis of Mr. Herbert Spencer
or that of Mr. Darwin, it is impossible to escape the conception of innate
internal forces. With regard to the physiological units of the former, Mr.
Spencer himself, as we have seen, distinctly attributes to them "an
_innate_ tendency" to evolve the parent form from which they sprang. With
regard to the gemmules of Mr. Darwin, we have seen, in Chapter X., with how
many innate powers, tendencies, and capabilities they must each be
severally endowed, to reproduce their kind, to evolve complex organisms or
cells, to exercise germinative affinity, &c.
If then (as was before said at the end of Chapter VIII.) such innate powers
must be attributed to chemical atoms, to mineral species, to gemmules, and
to physiological units, it is only reasonable to attribute such to each
individual organism.
The conception of such internal and latent capabilities is somewhat like
that of Mr. Galton, before mentioned, according to which the organic world
consists of entities, each of which is, as it were, a spheroid with many
facets on its surface, upon one of which it reposes in stable equilibrium.
When by the accumulated action of incident forces this equilibrium is {229}
disturbed, the spheroid is supposed to turn over until it settles on an
adjacent facet once more in stable equilibrium.
The internal tendency of an organism to certain considerable and definite
changes would correspond to the facets on the surface of the spheroid.
It may be objected that we have no knowledge as to how terrestrial,
cosmical and other forces can affect organisms so as to stimulate and
evolve these latent, merely potential forms. But we have had evidence that
such mysterious agencies _do_ affect organisms in ways as yet inexplicable,
in the very remarkable effects of geographical conditions which were
detailed in the third chapter.
It is quite conceivable that the material organic world may be so
constituted that the simultaneous action upon it of all known forces,
mechanical, physical, chemical, magnetic, terrestrial, and cosmical,
together with other as yet unknown forces which probably exist, may result
in changes which are harmonious and symmetrical, just as the internal
nature of vibrating plates causes particles of sand scattered over them to
assume definite and symmetrical figures when made to oscillate in different
ways by the bow of a violin being drawn along their edges. The results of
these combined internal powers and external influences might be represented
under the symbol of complex series of vibrations (analogous to those of
sound or light) forming a most complex harmony or a display of most varied
colours. In such a way the reparation of local injuries might be symbolized
as a filling up and completion of an interrupted rhythm. Thus also
monstrous aberrations from typical structure might correspond to a discord,
and sterility from crossing be compared with the darkness resulting from
the interference of waves of light.
Such symbolism will harmonize with the peculiar reproduction, before
mentioned, of heads in the body of certain annelids, with the facts of
serial homology, as well as those of bilateral and vertical symmetry. {230}
Also, as the atoms of a resonant body may be made to give out sound by the
juxtaposition of a vibrating tuning-fork, so it is conceivable that the
physiological units of a living organism may be so influenced by
surrounding conditions (organic and other) that the accumulation of these
conditions may upset the previous rhythm of such units, producing
modifications in them--a fresh chord in the harmony of nature--a new
species!
But it may be again objected that to say that species arise by the help of
an innate power possessed by organisms is no explanation, but is a
reproduction of the absurdity, _l'opium endormit parcequ'il a une vertu
soporifique_. It is contended, however, that this objection does not apply,
even if it be conceded that there is that force in Molière's ridicule which
is generally attributed to it.[231] Much, however, might be said in
opposition to more than one of that brilliant dramatist's smart
philosophical epigrams, just as to the theological ones of Voltaire, or to
the biological one of that other Frenchman who for a time discredited a
cranial skeletal theory by the phrase "Vertèbre pensante."[232]
In fact, however, it is a real explanation of how a man lives to say that
he lives independently, on his own income, instead of being supported by
his relatives and friends. In the same way, there is fully as real a
distinction between the production of new specific manifestations entirely
_ab externo_, and by the production of the same through an innate force and
tendency, the determination of which into action is occasioned by {231}
external circumstances.
To say that organisms possess this innate power, and that by it new species
are from time to time produced, is by no means a mere assertion that they
_are_ produced, and in an unknown mode. It is the negation of that view
which deems external forces alone sufficient, and at the same time the
assertion of something positive, to be arrived at by the process of
_reductio ad absurdum_.
All physical explanations result ultimately in such conceptions of innate
power, or else in that of will force. The far-famed explanation of the
celestial motions ends in the conception that every particle of matter has
the innate power of attracting every other particle directly as the mass,
and inversely as the square of the distance.
We are logically driven to this positive conception if we do not accept the
view that there is no force but volition, and that all phenomena whatever
are the immediate results of the action of intelligent and self-conscious
will.
We have seen that the notion of sudden changes--saltatory actions in
nature--has received countenance from Professor Huxley.[233] We must
conceive that these jumps are orderly, and according to law, inasmuch as
the whole cosmos is such. Such orderly evolution harmonizes with a
teleology derived, not indeed from external nature directly, but from the
mind of man. On this point, however, more will be said in the next chapter.
But, once more, if new species are not manifested by the action of external
conditions upon minute indefinite individual differences, in what precise
way may we conceive that manifestation to have taken place?
Are new species now evolving, as they have been from time to time evolved?
If so, in what way and by what conceivable means?
{232}
In the first place, they must be produced by natural action in pre-existing
material, or by supernatural action.
For reasons to be given in the next chapter, the second hypothesis need not
be considered.
If, then, new species are and have been evolved from pre-existing material,
must that material have been organic or inorganic?
As before said, additional arguments have lately been brought forward to
show that individual organisms _do_ arise from a basis of _in_-organic
material only. As, however, this at the most appears to be the case, if at
all, only with the lowest and most minute organisms exclusively, the
process cannot be observed, though it may perhaps be fairly inferred.
We may therefore, if for no other reason, dismiss the notion that highly
organized animals and plants can be suddenly or gradually built up by any
combination of physical forces and natural powers acting externally and
internally upon and in merely inorganic material as a base.
But the question is, how have the highest kinds of animals and plants
arisen? It seems impossible that they can have appeared otherwise than by
the agency of antecedent organisms not greatly different from them.
A multitude of facts, ever increasing in number and importance, all point
to such a mode of specific manifestation.
One very good example has been adduced by Professor Flower in the
introductory lecture of his first Hunterian Course.[234] It is the
reduction in size, to a greater or less degree, of the second and third
digits of the foot in Australian marsupials, and this, in spite of the very
different form and function of the foot in different groups of those
animals.
A similarly significant evidence of relationship is afforded by processes
of the zygomatic region of the skull in certain edentates existing and
extinct.
{233}
Again, the relation between existing and recent faunas of the different
regions of the world, and the predominating (though by no means exclusive)
march of organization, from the more general to the more special, point in
the same direction.
Almost all the facts brought forward by the patient industry of Mr. Darwin
in support of his theory of "Natural Selection," are of course available as
evidence in favour of the agency of pre-existing and similar animals in
specific evolution.
Now the new forms must be produced by changes taking place in organisms in,
after or before their birth, either in their embryonic, or towards or in
their adult, condition.
Examples of strange births are sufficiently common, and they may arise
either from direct embryonic modifications or apparently from some obscure
change in the parental action. To the former category belong the hosts of
instances of malformation through arrest of development, and perhaps
generally monstrosities of some sort are the result of such affections of
the embryo. To the second category belong all cases of hybridism, of cross
breed, and in all probability the new varieties and forms, such as the
memorable one of the black-shouldered peacock. In all these cases we do not
have abortions or monstrosities, but more or less harmonious forms often of
great functional activity, endowed with marked viability and generative
prepotency, except in the case of hybrids, when we often find even a more
marked generative impotency.
It seems probable therefore that new species may arise from some
constitutional affection of parental forms--an affection mainly, if not
exclusively, of their generative system. Mr. Darwin has carefully
collected[235] numerous instances to show how excessively sensitive to
various influences this system is. He says:[236] "Sterility is independent
of general health, and is often accompanied by excess of size, or {234}
great luxuriance," and, "No one can tell, till he tries; whether any
particular animal will breed under confinement, or any exotic plant seed
freely under culture." Again, "When a new character arises, whatever its
nature may be, it generally tends to be inherited, at least in a temporary
and sometimes in a most persistent manner."[237] Yet the obscure action of
conditions will alter characters long inherited, as the grandchildren of
Aylesbury ducks, removed to a distant part of England, completely lost
their early habit of incubation, and hatched their eggs at the same time
with the common ducks of the same place.[238]
Mr. Darwin quotes Mr. Bartlett as saying: "It is remarkable that lions
breed more freely in travelling collections than in the zoological gardens;
probably the constant excitement and irritation produced by moving from
place to place, or change of air, may have considerable influence in the
matter."[239]
Mr. Darwin also says: "There is reason to believe that insects are affected
by confinement like the higher animals," and he gives examples.[240]
Again, he gives examples of change of plumage in the linnet, bunting,
oriole, and other birds, and of the temporary modification of the horns of
a male deer during a voyage.[241]
Finally, he adds that these changes cannot be attributed to loss of health
or vigour, "when we reflect how healthy, long-lived, and vigorous many
animals are under captivity, such as parrots, and hawks when used for
hawking, chetahs when used for hunting, and elephants. The reproductive
organs themselves are not diseased; and the diseases from which animals in
menageries usually perish, are not those which in any way affect their
fertility. No domestic animal is more subject to disease than the sheep,
yet it is remarkably prolific.... It would appear that any change in {235}
the habits of life, whatever these habits may be, if great enough, tends to
affect in an inexplicable manner the powers of reproduction."
Such, then, is the singular sensitiveness of the generative system.
As to the means by which that system is affected, we see that a variety of
conditions affect it; but as to the modes in which they act upon it, we
have as yet little if any clue.
We have also seen the singular effects (in tailed Lepidoptera, &c.) of
causes connected with geographical distribution, the mode of action of
which is as yet quite inexplicable; and we have also seen the innate
tendency which there appears to be in certain groups (birds of paradise,
&c.) to develop peculiarities of a special kind.
It is, to say the least, probable that other influences exist, terrestrial
and cosmical, as yet un-noted. The gradually accumulating or diversely
combining actions of all these on highly sensitive structures, which are
themselves possessed of internal responsive powers and tendencies, may well
result in occasional repeated productions of forms harmonious and vigorous,
and differing from the parental forms in proportion to the result of the
combining or conflicting action of all external and internal influences.
If, in the past history of this planet, more causes ever intervened, or
intervened more energetically than at present, we might _a priori_ expect a
richer and more various evolution of forms more radically differing than
any which could be produced under conditions of more perfect equilibrium.
At the same time, if it be true that the last few thousand years have been
a period of remarkable and exceptional uniformity as regards this planet's
astronomical relations, there are then some grounds for thinking that
organic evolution may have been exceptionally depressed during the same
epoch.
Now, as to the fact that sudden changes and sudden developments have {236}
occurred, and as to the probability that such changes are likely to occur,
evidence was given in Chapter IV.
In Chapter V. we also saw that minerals become modified suddenly and
considerably by the action of incident forces--as, _e.g._, the production
of hexagonal tabular crystals of carbonate of copper by sulphuric acid, and
of long rectangular prisms by ammonia, &c.
We have thus a certain antecedent probability that if changes are produced
in specific manifestation through incident forces, these changes will be
sensible and considerable, not minute and infinitesimal.
Consequently, it is probable that new species have appeared from time to
time with comparative suddenness, and that they still continue so to arise
if all the conditions necessary for specific evolution now obtain.
This probability will be increased if the observations of Dr. Bastian are
confirmed by future investigation. According to his report, when the
requisite conditions were supplied, the transformations which appeared to
take place (from very low to higher organisms) were sudden, definite, and
complete.
Therefore, if this is so, there must probably exist in higher forms a
similar tendency to such change. That tendency may indeed be long
suppressed, and ultimately modified by the action of heredity--an action
which would increase in force with the increase in the perfection and
complexity of the organism affected. Still we might expect that such
changes as do take place would be also sudden, definite, and complete.
Moreover, as the same causes produce the same effects, several individual
parent forms must often have been similarly and simultaneously affected.
That they should be so affected--at least that several similarly modified
individuals should simultaneously arise--has been seen to be a generally
necessary circumstance for the permanent duration of such new
modifications.
It is also conceivable that such new forms may be endowed with {237}
excessive constitutional strength and viability, and with generative
prepotency, as was the case with the black-shouldered peacock in Sir J.
Trevelyan's flock. This flock was entirely composed of the common kind, and
yet the new form rapidly developed itself "_to the extinction of the
previously existing breed_."[242]
Indeed, the notion accepted by both Mr. Darwin and Mr. Herbert Spencer, and
which is plainly the fact (namely, that changes of conditions and incident
forces, within limits, augment the viability and fertility of individuals),
harmonizes well with the suggested possibility as to an augmented viability
and prepotency in new organic forms evolved by peculiar consentaneous
actions of conditions and forces, both external and internal.
The remarkable series of changes noted by Dr. Bastian were certainly not
produced by external incident forces _only_, but by these acting on a
peculiar _materia_, having special properties and powers. Therefore, the
changes were induced by the consentaneous action of internal and external
forces.[243] In the same way then, we may expect changes in higher forms to
be evolved by similar united action of internal and external forces.
One other point may here be alluded to. When the remarkable way in which
structure and function simultaneously change, is borne in mind; when those
numerous instances in which nature has supplied similar wants by similar
means, as detailed in Chapter III., are remembered; when also all the
wonderful contrivances of orchids, of mimicry, and the strange complexity
of certain instinctive actions are considered: then the conviction forces
itself on many minds that the organic world is the expression of an
intelligence of some kind. This view has been well advocated by Mr. Joseph
John Murphy, in his recent work so often here referred to.
{238}
This intelligence, however, is evidently not altogether such as ours, or
else has other ends in view than those most obvious to us. For the end is
often attained in singularly roundabout ways, or with a prodigality of
means which seems out of all proportion with the result: not with the
simple action directed to one end which generally marks human activity.
Organic nature then speaks clearly to many minds of the action of an
intelligence resulting, on the whole and in the main, in order, harmony,
and beauty, yet of an intelligence the ways of which are not such as ours.
This view of evolution harmonizes well with Theistic conceptions; not, of
course, that this harmony is brought forward as an argument in its favour
generally, but it will have weight with those who are convinced that Theism
reposes upon solid grounds of reason as _the_ rational view of the
universe. To such it may be observed that, thus conceived, the Divine
action has that slight amount of resemblance to, and that wide amount of
divergence from what human action would be, which might be expected _a
priori_--might be expected, that is, from a Being whose nature and aims are
utterly beyond our power to imagine, however faintly, but whose truth and
goodness are the fountain and source of our own perceptions of such
qualities.
The view of evolution maintained in this work, though arrived at in
complete independence, yet seems to agree in many respects with the views
advocated by Professor Owen in the last volume of his "Anatomy of
Vertebrates," under the term "derivation." He says:[244] "Derivation holds
that every species changes in time, by virtue of inherent tendencies
thereto. 'Natural Selection' holds that no such change can take place
without the influence of altered external circumstances.[245] {239}
'Derivation' sees among the effects of the innate tendency to change
irrespective of altered circumstances, a manifestation of creative power in
the variety and beauty of the results; and, in the ultimate forthcoming of
a being susceptible of appreciating such beauty, evidence of the
pre-ordaining of such relation of power to the appreciation. 'Natural
Selection' acknowledges that if ornament or beauty, in itself, should be a
purpose in creation, it would be absolutely fatal to it as a hypothesis."
"'Natural Selection' sees grandeur in the view of life, with its several
powers, having been originally breathed by the Creator into a few forms or
into one. 'Derivation' sees therein a narrow invocation of a special
miracle and an unworthy limitation of creative power, the grandeur of which
is manifested daily, hourly, in calling into life many forms, by conversion
of physical and chemical into vital modes of force, under as many
diversified conditions of the requisite elements to be so combined."
The view propounded in this work allows, however, a greater and more
important part to the share of external influences, it being believed by
the Author, however, that these external influences equally with the
internal ones are the results of one harmonious action underlying the whole
of nature, organic and inorganic, cosmical, physical, chemical,
terrestrial, vital, and social.
According to this view, an internal law presides over the actions of every
part of every individual, and of every organism as a unit, and of the
entire organic world as a whole. It is believed that this conception of an
internal innate force will ever remain necessary, however much its
subordinate processes and actions may become explicable:
That by such a force, from time to time, new species are manifested by
ordinary generation just as _Pavo nigripennis_ appeared suddenly, these new
forms not being monstrosities but harmonious self-consistent wholes. That
thus, as specific distinctness is manifested by obscure sexual {240}
conditions, so in obscure sexual modifications specific distinctions arise.
That these "jumps" are considerable in comparison with the minute
variations of "Natural Selection"--are in fact sensible steps, such as
discriminate species from species.
That the latent tendency which exists to these sudden evolutions is
determined to action by the stimulus of external conditions.
That "Natural Selection" rigorously destroys monstrosities, and abortive
and feeble attempts at the performance of the evolutionary process.
That "Natural Selection" removes the antecedent species rapidly when the
new one evolved is more in harmony with surrounding conditions.
That "Natural Selection" favours and develops useful variations, though it
is impotent to originate them or to erect the physiological barrier which
seems to exist between species.
By some such conception as this, the difficulties here enumerated, which
beset the theory of "Natural Selection" pure and simple, are to be got
over.
Thus, for example, the difficulties discussed in the first chapter--namely,
those as to the origins and first beginnings of certain structures--are
completely evaded.
Again, as to the independent origin of closely similar structures, such as
the eyes of the Vertebrata and cuttle-fishes, the difficulty is removed if
we may adopt the conception of an innate force similarly directed in each
case, and assisted by favourable external conditions.
Specific stability, limitation to variability, and the facts of reversion,
all harmonize with the view here put forward. The same may be said with
regard to the significant facts of homology, and of organic symmetry; and
our consideration of the hypothesis of Pangenesis in Chapter X., has seemed
to result in a view as to innate powers which accords well with what is
here advocated. [Page 241]
The evolutionary hypothesis here advocated also serves to explain all those
remarkable facts which were stated in the first chapter to be explicable by
the theory of Natural Selection, namely, the relation of existing to recent
faunas and floras; the phenomena of homology and of rudimentary structures;
also the processes gone through in development; and lastly, the wonderful
facts of mimicry.
Finally, the view adopted is the synthesis of many distinct and, at first
sight, conflicting conceptions, each of which contains elements of truth,
and all of which it appears to be able more or less to harmonize.
Thus it has been seen that "Natural Selection" is accepted. It acts and
must act, though alone it does not appear capable of fulfilling the task
assigned to it by Mr. Darwin.
Pangenesis has probably also much truth in it, and has certainly afforded
valuable and pregnant suggestions, but unaided and alone it seems
inadequate to explain the evolution of the individual organism.
Those three conceptions of the organic world which may be spoken of as the
teleological, the typical, and the transmutationist, have often been
regarded as mutually antagonistic and conflicting.
The genesis of species as here conceived, however, accepts, locates, and
harmonizes all the three.
Teleology concerns the ends for which organisms were designed. The
recognition, therefore, that their formation took place by an evolution not
fortuitous, in no way invalidates the acknowledgment of their final causes
if on other grounds there are reasons for believing that such final causes
exist.
Conformity to type, or the creation of species according to certain "divine
ideas," is in no way interfered with by such a process of evolution as is
here advocated. Such "divine ideas" must be accepted or declined upon quite
other grounds than the mode of their realization, and of their
manifestation in the world of sensible phenomena. [Page 242]
Transmutationism (an old name for the evolutionary hypothesis), which was
conceived at one time to be the very antithesis to the two preceding
conceptions, harmonizes well with them if the evolution be conceived to be
orderly and designed. It will in the next chapter be shown to be completely
in harmony with conceptions, upon the acceptance of which "final causes"
and "divine ideal archetypes" alike depend.
Thus then, if the cumulative argument put forward in this book is valid, we
must admit the insufficiency of Natural Selection both on account of the
residuary phenomena it fails to explain, and on account of certain other
phenomena which seem actually to conflict with that theory. We have seen
that though the laws of nature are constant, yet some of the conditions
which determine specific change may be exceptionally absent at the present
epoch of the world's history; also that it is not only possible, but highly
probable, that an internal power or tendency is an important if not the
main agent in evoking the manifestation of new species on the scene of
realized existence, and that in any case, from the facts of homology,
innate internal powers to the full as mysterious must anyhow be accepted,
whether they act in specific origination or not. Besides all this, we have
seen that it is probable that the action of this innate power is
stimulated, evoked, and determined by external conditions, and also that
the same external conditions, in the shape of "Natural Selection," play an
important part in the evolutionary process: and finally, it has been
affirmed that the view here advocated, while it is supported by the facts
on which Darwinism rests, is not open to the objections and difficulties
which oppose themselves to the reception of "Natural Selection," as the
exclusive or even as the main agent in the successive and orderly evolution
of organic forms in the _genesis of species_. [Page 243]
* * * * *
CHAPTER XII.
THEOLOGY AND EVOLUTION.
Prejudiced opinions on the subject.--"Creation" sometimes denied from
prejudice.---The unknowable.--Mr. Herbert Spencer's objections to
theism; to creation.--Meanings of term "creation."--Confusion from not
distinguishing between "primary" and "derivative" creation.--Mr.
Darwin's objections.--Bearing of Christianity on the theory of
evolution.--Supposed opposition, the result of a
misconception.--Theological authority not opposed to evolution.--St.
Augustin.--St. Thomas Aquinas.--Certain consequences of want of
flexibility of mind.--Reason and imagination.--The first cause and
demonstration.--Parallel between Christianity and natural
theology.--What evolution of species is.--Professor Agassiz.--Innate
powers must be recognized.--Bearing of evolution on religious
belief.--Professor Huxley.--Professor Owen.--Mr. Wallace.--Mr.
Darwin.--_A priori_ conception of Divine action.--Origin of
man.--Absolute creation and dogma.--Mr. Wallace's view.--A supernatural
origin for man's body not necessary.--Two orders of being in man.--Two
modes of origin.--Harmony of the physical, hyperphysical, and
supernatural.--Reconciliation of science and religion as regards
evolution.--Conclusion.
The special "Darwinian Theory" and that of an evolutionary process neither
excessively minute nor fortuitous, having now been considered, it is time
to turn to the important question, whether both or either of these
conceptions may have any bearing, and if any, what, upon Christian belief?
Some readers will consider such an inquiry to be a work of supererogation.
Seeing clearly themselves the absurdity of prevalent popular views, and the
shallowness of popular objections, they may be impatient of any discussion,
on the subject. But it is submitted that there are many minds worthy {244}
of the highest esteem and of every consideration, which have regarded the
subject hitherto almost exclusively from one point of view; that there are
some persons who are opposed to the progress (in their own minds or in that
of their children or dependents) of physical scientific truth--the natural
revelation--through a mistaken estimate of its religious bearings, while
there are others who are zealous in its promotion from a precisely similar
error. For the sake of both these then the Author may perhaps be pardoned
for entering slightly on very elementary matters relating to the question,
whether evolution or Darwinism have any, and if any, what, bearing on
theology?
There are at least two classes of men who will certainly assert that they
have a very important and highly significant bearing upon it.
One of these classes consists of persons zealous for religion indeed, but
who identify orthodoxy with their own private interpretation of Scripture
or with narrow opinions in which they have been brought up--opinions
doubtless widely spread, but at the same time destitute of any distinct and
authoritative sanction on the part of the Christian Church.
The other class is made up of men hostile to religion, and who are glad to
make use of any and every argument which they think may possibly be
available against it.
Some individuals within this latter class may not believe in the existence
of God, but may yet abstain from publicly avowing this absence of belief,
contenting themselves with denials of "creation" and "design," though these
denials are really consequences of their attitude of mind respecting the
most important and fundamental of all beliefs.
Without a distinct belief in a personal God it is impossible to have any
religion worthy of the name, and no one can at the same time accept the
Christian religion and deny the dogma of creation. [Page 245]
"I believe in God," "the Creator of Heaven and Earth," the very first
clauses of the Apostles' Creed, formally commit those who accept them to
the assertion of this belief. If, therefore, any theory of physical science
really conflicts with such an authoritative statement, its importance to
Christians is unquestionable.
As, however, "creation" forms a part of "revelation," and as "revelation"
appeals for its acceptance to "reason" which has to prepare a basis for it
by an intelligent acceptance of theism on _purely rational grounds_, it is
necessary to start with a few words as to the reasonableness of belief in
God, which indeed are less superfluous than some readers may perhaps
imagine; "a few words," because this is not the place where the argument
can be drawn out, but only one or two hints given in reply to certain
modern objections.
No better example perhaps can be taken, as a type of these objections, than
a passage in Mr. Herbert Spencer's First Principles.[246] This author
constantly speaks of the "ultimate cause of things" as "the Unknowable," a
term singularly unfortunate, and as Mr. James Martineau has pointed
out,[247] even self-contradictory: for that entity, the knowledge of {246}
the existence of which presses itself ever more and more upon the
cultivated intellect, cannot be the unknown, still less _the unknowable_,
because we certainly know it, in that we know for certain that it exists.
Nay more, to predicate incognoscibility of it, is even a certain knowledge
of the mode of its existence. Mr. H. Spencer says:[248] "The consciousness
of an Inscrutable Power manifested to us through all phenomena has been
growing ever clearer; and must eventually be freed from its imperfections.
The certainty that on the one hand such a Power exists, while on the other
hand its nature transcends intuition, and is beyond imagination, is the
certainty towards which intelligence has from the first been progressing."
One would think then that the familiar and accepted word "the Inscrutable"
(which is in this passage actually employed, and to which no theologian
would object) would be an indefinitely better term than "the unknowable."
The above extract has, however, such a theistic aspect that some readers
may think the opposition here offered superfluous; it may be well,
therefore, to quote two other sentences. In another place he observes,[249]
"Passing over the consideration of credibility, and confining ourselves to
that of conceivability, we see that atheism, pantheism, and theism, when
rigorously analysed, severally prove to be absolutely unthinkable;" and
speaking of "every form of religion," he adds,[250] "The analysis of every
possible hypothesis proves, not simply that no hypothesis is sufficient but
that no hypothesis is even thinkable." The unknowable is admitted to be a
power which cannot be regarded as having sympathy with us, but as one to
which no emotion whatever can be ascribed, and we are expressly {247}
forbidden "by _duty_," to affirm personality of God as much as to deny it
of Him. How such a being can be presented as an object on which to exercise
religious emotion it is difficult indeed to understand.[251] Aspiration,
love, devotion to be poured forth upon what we can never know, upon what we
can never affirm to know, or care for, us, our thoughts or actions, or to
possess the attributes of wisdom and goodness! The worship offered in such
a religion must be, as Professor Huxley says,[252] "for the most part of
the silent sort"--silent not only as to the spoken word, but silent as to
the mental conception also. It will be difficult to distinguish the
follower of this religion from the follower of none, and the man who
declines either to assert or to deny the existence of God, is practically
in the position of an atheist. For theism enjoins the cultivation of
sentiments of love and devotion to God, and the practice of their external
expression. Atheism forbids both, while the simply non-theist abstains in
conformity with the prohibition of the atheist and thus practically sides
with him. Moreover, since man cannot imagine that of which he has no
experience in any way whatever, and since he has experience only of _human_
perfections and of the powers and properties of _inferior_ existences; if
he be required to deny human perfections and to abstain from making use of
such conceptions, he is thereby necessarily reduced to others of an
inferior order. Mr. H. Spencer says,[253] "Those who espouse this {248}
alternative position, make the erroneous assumption that the choice is
between personality and something lower than personality; whereas the
choice is rather between personality and something higher. Is it not just
possible that there is a mode of being as much transcending intelligence
and will, as these transcend mechanical motion?"
"It is true we are totally unable to conceive any such higher mode of
being. But this is not a reason for questioning its existence; it is rather
the reverse." "May we not therefore rightly refrain from assigning to the
'ultimate cause' any attributes whatever, on the ground that such
attributes, derived as they must be from our own natures, are not
elevations but degradations?" The way however to arrive at the object aimed
at (_i.e_. to obtain the best attainable conception of the First Cause) is
not to refrain from _the only conceptions possible to us_, but to seek the
very highest of these, and then declare their utter inadequacy; and this is
precisely the course which has been pursued by theologians. It is to be
regretted that before writing on this matter Mr. Spencer did not more
thoroughly acquaint himself with the ordinary doctrine on the subject. It
is always taught in the Church schools of divinity, that nothing, not even
_existence_, is to be predicated _univocally_ of "God" and "creatures;"
that after exhausting ingenuity to arrive at the loftiest possible
conceptions, we must declare them to be _utterly inadequate_; that, after
all, they are but accommodations to human infirmity; that they are in a
sense objectively false (because of their inadequacy), though subjectively
and very practically true. But the difference between this mode of
treatment and that adopted by Mr. Spencer is wide indeed; for the practical
result of the mode inculcated by the Church is that each one may freely
affirm and act upon the highest human conceptions he can attain of the{249}
power, wisdom, and goodness of God, His watchful care, His loving
providence for every man, at every moment and in every need; for the
Christian knows that the falseness of his conceptions lies only in their
_inadequacy_; he may therefore strengthen and refresh himself, may rejoice
and revel in conceptions of the goodness of God, drawn from the tenderest
human images of fatherly care and love, or he may chasten and abase himself
by consideration of the awful holiness and unapproachable majesty of the
Divinity derived from analogous sources, knowing that no thought of man can
ever be _true enough_, can ever attain the incomprehensible reality, which
nevertheless really _is_ all that can be conceived, _plus_ an inconceivable
infinity beyond.
A good illustration of what is here meant, and of the difference between
the theistic position and Mr. Spencer's, may be supplied by an example he
has himself proposed. Thus,[254] he imagines an intelligent watch
speculating as to its maker, and conceiving of him in terms of watch-being,
and figuring him as furnished with springs, escapements, cogged wheels,
&c., his motions facilitated by oil--in a word, like himself. It is assumed
by Mr. Spencer that this necessary watch conception would be completely
false, and the illustration is made use of to show "the presumption of
theologians"--the absurdity and unreasonableness of those men who figure
the incomprehensible cause of all phenomena as a Being in some way
comparable with man. Now, putting aside for the moment all other
considerations, and accepting the illustration, surely the example
demonstrates rather the unreasonableness of the _objector himself_! It is
true, indeed, that a man is an organism indefinitely more complex and
perfect than any watch; but if the watch could only conceive of its maker
in watch terms, or else in terms altogether inferior, the watch would
plainly be right in speaking of its maker as a, to it, inconceivably {250}
perfect kind of watch, acknowledging at the same time, that this, its
conception of him, was _utterly inadequate_, although the best its inferior
nature allowed it to form. For if, instead of so conceiving of its maker,
it refused to make use of these relative perfections as a makeshift, and so
necessarily thought of him as amorphous metal, or mere oil, or by the help
of any other inferior conception which a watch might be imagined capable of
entertaining, that watch would he wrong indeed. For man can much more
properly be compared with, and has much more affinity to, a perfect watch
in full activity than to a mere piece of metal, or drop of oil. But the
watch is even more in the right still, for its maker, man, virtually _has_
the cogged wheels, springs, escapements, oil, &c., which the watch's
conception has been supposed to attribute to him; inasmuch as all these
parts must have existed as distinct ideas in the human watchmaker's mind
before he could actually construct the clock formed by him. Nor is even
this all, for, by the hypothesis, the watch _thinks_. It must, therefore,
think of its maker as "a thinking being," and in this it is _absolutely and
completely right_.[255] Either, therefore, the hypothesis is _absurd_ or it
actually _demonstrates the very position it was chosen to refute_.
Unquestionably, then, on the mere ground taken by Mr. Herbert Spencer
himself, if we are compelled to think of the First Cause either in human
terms (but with human imperfections abstracted and human perfections
carried to the highest conceivable degree), or, on the other hand, in terms
decidedly inferior, such as those are driven to who think of Him, but
decline to accept as a help the term "personality;" there can be no
question but that the first conception is immeasurably nearer the truth
than the second. Yet the latter is the one put forward and advocated by
that author in spite of its unreasonableness, and in spite also of its{251}
conflicting with the whole moral nature of man and all his noblest
aspirations.
Again, Mr. Herbert Spencer objects to the conception of God as "first
cause," on the ground that "when our symbolic conceptions are such that no
cumulative or indirect processes of thought can enable us to ascertain that
there are corresponding actualities, nor any predictions be made whose
fulfilment can prove this, then they are altogether vicious and illusive,
and in no way distinguishable from pure fictions."[256]
Now, it is quite true that "symbolic conceptions," which are not to be
justified either (1) by presentations of sense, or (2) by intuitions, are
invalid as representations of real truth. Yet the conception of God
referred to _is_ justified by our primary intuitions, and we can assure
ourselves that it _does_ stand for an actuality by comparing it with (1)
our intuitions of free-will and causation, and (2) our intuitions of
morality and responsibility. That we _have_ these intuitions is a point on
which the Author joins issue with Mr. Spencer, and confidently affirms that
they cannot logically be denied without at the same time complete and
absolute scepticism resulting from such denial--scepticism wherein vanishes
any certainty as to the existence both of Mr. Spencer and his critic, and
by which it is equally impossible to have a thought free from doubt, or to
go so far as to affirm the existence of that very doubt or of the doubter
who doubts it.
It may not be amiss here to protest against the intolerable assumption of a
certain school, who are continually talking in lofty terms of "science,"
but who actually speak of primary religious conceptions as "unscientific,"
and habitually employ the word "science," when they should limit it by the
prefix "physical." This is the more amazing as not a few of this school
adopt the idealist philosophy, and affirm that "matter and force" are but
names for certain "modes of consciousness." It might be expected of them at
least to admit that opinions which repose on primary and fundamental {252}
intuitions, are especially and _par excellence_ scientific.
Such are some of the objections to the Christian conception of God. We may
now turn to those which are directed against God as the Creator, _i.e._ as
the absolute originator of the universe, without the employment of any
pre-existing means or material. This is again considered by Mr. Spencer as
a thoroughly illegitimate symbolic conception, as much so as the atheistic
one--the difficulty as to a _self-existent Creator_ being in his opinion
equal to that of a _self-existent universe_. To this it may be replied that
both are of course equally _unimaginable_, but that it is not a question of
facility of conception--not which is easiest to conceive, but which best
accounts for, and accords with, psychological facts; namely, with the
above-mentioned intuitions. It is contended that _we have_ these primary
intuitions, and that with these the conception of a self-existent Creator
is perfectly harmonious. On the other hand, the notion of a self-existent
universe--that there is no real distinction between the finite and the
infinite--that the universe and ourselves are one and the same things with
the infinite and the self-existent; these assertions, in _addition to_
being unimaginable, _contradict_ our primary intuitions.
Mr. Darwin's objections to "Creation" are of quite a different kind, and,
before entering upon them, it will be well to endeavour clearly to
understand what we mean by "Creation," in the various senses in which the
term may be used.
In the strictest and highest sense "Creation" is the absolute origination
of anything by God without pre-existing means or material, and is a
_supernatural_ act.[257]
In the secondary and lower sense, "Creation" is the formation of anything
by God _derivatively_; that is, that the preceding matter has been created
with the potentiality to evolve from it, under suitable conditions, {253}
all the various forms it subsequently assumes. And this power having been
conferred by God in the first instance, and those laws and powers having
been instituted by Him, through the action of which the suitable conditions
are supplied, He is said in this lower sense to create such various
subsequent forms. This is the _natural_ action of God in the physical
world, as distinguished from His direct, or, as it may be here called,
supernatural action.
In yet a third sense, the word "Creation" may be more or less improperly
applied to the construction of any complex formation or state by a
voluntary self-conscious being who makes use of the powers and laws which
God has imposed, as when a man is spoken of as the creator of a museum, or
of "his own fortune," &c. Such action of a created conscious intelligence
is purely natural, but more than physical, and may be conveniently spoken
of as hyperphysical.
We have thus (1) direct or supernatural action; (2) physical action; and
(3) hyperphysical action---the two latter both belonging to the order of
nature.[258] Neither the physical nor the hyperphysical actions, however,
exclude the idea of the Divine concurrence, and with every consistent
theist that idea is necessarily included. Dr. Asa Gray has given expression
to this.[259] He says, "Agreeing that plants and animals were produced by
Omnipotent fiat, does not exclude the idea of natural order and what we
call secondary causes. The record of the fiat--'Let the earth bring forth
grass, the herb yielding seed,' &c., 'let the earth bring forth the living
creature after his kind'--seems even to imply them," and leads to the
conclusion that the various kinds were produced through natural agencies.
{254}
Now, much confusion has arisen from not keeping clearly in view this
distinction between _absolute_ creation and _derivative_ creation. With the
first, physical science has plainly nothing whatever to do, and is impotent
to prove or to refute it. The second is also safe from any attack on the
part of physical science, for it is primarily derived from psychical not
physical phenomena. The greater part of the apparent force possessed by
objectors to creation, like Mr. Darwin, lies in their treating the
assertion of derivative creation as if it was an assertion of absolute
creation, or at least of supernatural action. Thus, he asks whether some of
his opponents believe "that at innumerable periods in the earth's history,
certain elemental atoms have been commanded suddenly to flash into living
tissues."[260] Certain of Mr. Darwin's objections, however, are not
physical, but _metaphysical_, and really attack the dogma of secondary or
derivative creation, though to some perhaps they may appear to be directed
against absolute creation only.
Thus he uses, as an illustration, the conception of a man who builds an
edifice from fragments of rock at the base of a precipice, by selecting for
the construction of the various parts of the building the pieces which are
the most suitable owing to the shape they happen to have broken into.
Afterwards, alluding to this illustration, he says,[261] "The shape of the
fragments of stone at the base of our precipice may be called accidental,
but this is not strictly correct, for the shape of each depends on a long
sequence of events, all obeying natural laws, on the nature of the rock, on
the lines of stratification or cleavage, on the form of the mountain which
depends on its upheaval and subsequent denudation, and lastly, on the storm
and earthquake which threw down the fragments. But in regard to the use to
which the fragments may be put, their shape may strictly be said to be{255}
accidental. And here we are led to face a great difficulty, in alluding to
which I am aware that I am travelling beyond my proper province."
"An omniscient Creator must have foreseen every consequence which results
from the laws imposed by Him; but can it be reasonably maintained that the
Creator intentionally ordered, if we use the words in any ordinary sense,
that certain fragments of rock should assume certain shapes, so that the
builder might erect his edifice? If the various laws which have determined
the shape of each fragment were not predetermined for the builder's sake,
can it with any greater probability be maintained that He specially
ordained, for the sake of the breeder, each of the innumerable variations
in our domestic animals and plants--many of these variations being of no
service to man, and not beneficial, far more often injurious, to the
creatures themselves? Did He ordain that the crop and tail-feathers of the
pigeon should vary, in order that the fancier might make his grotesque
pouter and fantail breeds? Did He cause the frame and mental qualities of
the dog to vary, in order that a breed might be formed of indomitable
ferocity, with jaws fitted to pin down the bull for man's brutal sport?
But, if we give up the principle in one case---if we do not admit that the
variations of the primeval dog were intentionally guided, in order that the
greyhound, for instance, that perfect image of symmetry and vigour, might
be formed,--no shadow of reason can be assigned for the belief that the
variations, alike in nature, and the result of the same general laws, which
have been the groundwork through Natural Selection of the formation of the
most perfectly adapted animals in the world, man included, were
intentionally and specially guided. However much we may wish it, we can
hardly follow Professor Asa Gray in his belief that 'variation has been led
along certain beneficial lines,' like a stream 'along definite and useful
lines of irrigation.'"
"If we assume that each particular variation was from the beginning of{256}
all time pre-ordained, the plasticity of the organization, which leads to
many injurious deviations of structure, as well as that redundant power of
reproduction which inevitably leads to a struggle for existence, and, as a
consequence, to the Natural Selection and survival of the fittest, must
appear to us superfluous laws of nature. On the other hand, an omnipotent
and omniscient Creator ordains everything and foresees everything. Thus we
are brought face to face with a difficulty as insoluble as is that of
freewill and predestination."
Before proceeding to reply to this remarkable passage, it may be well to
remind some readers that belief in the existence of God, in His primary
creation of the universe, and in His derivative creation of all kinds of
being, inorganic and organic, do not repose upon physical phenomena, but,
as has been said, on primary intuitions. To deny or ridicule any of these
beliefs on physical grounds is to commit the fallacy of _ignoratio
elenchi_. It is to commit an absurdity analogous to that of saying a blind
child could not recognize his father because he could not _see_ him,
forgetting that he could _hear_ and _feel_ him. Yet there are some who
appear to find it unreasonable and absurd that men should regard phenomena
in a light not furnished by or deducible from the very phenomena
themselves, although the men so regarding them avow that the light in which
they do view them comes from quite another source. It is as if a man, A,
coming into B's room and finding there a butterfly, should insist that B
had no right to believe that the butterfly had not flown in at the open
window, inasmuch as there was nothing about the room or insect to lead to
any other belief; while B can well sustain his right so to believe, he
having met C, who told him he brought in the chrysalis and, having seen the
insect emerge, took away the skin.
By a similarly narrow and incomplete view the assertion that human
conceptions, such as "the vertebrate idea," &c., are ideas in the mind of
God, is sometimes ridiculed; as if the assertors either on the one {257}
hand pretended to some prodigious acuteness of mind--a far-reaching genius
not possessed by most naturalists--or, on the other hand, as if they
detected in the very phenomena furnishing such special conception evidences
of Divine imaginings. But let the idea of God, according to the highest
conceptions of Christianity, be once accepted, and then it becomes simply a
truism to say that the mind of the Deity contains all that is _good_ and
_positive_ in the mind of man, _plus_, of course, an absolutely
inconceivable infinity beyond. That thus such human conceptions may, nay
must, be asserted to be at the same time ideas in the Divine mind also, as
every real and separate individual that has been, is, or shall be, is
present to the same mind. Nay, more, that such human conceptions are but
faint and obscure adumbrations of corresponding ideas which exist in the
mind of God in perfection and fulness.[262]
The theist, having arrived at his theistic convictions from quite other
sources than a consideration of zoological or botanical phenomena, {258}
returns to the consideration of such phenomena and views them in a theistic
light without of course asserting or implying that such light has been
derived _from them_, or that there is an obligation of reason so to view
them on the part of others who refuse to enter upon or to accept those
other sources whence have been derived the theistic convictions of the
theist.
But Mr. Darwin is not guilty of arguing against metaphysical ideas on
physical grounds only, for he employs very distinctly metaphysical ones;
namely, his conceptions of the nature and attributes of the First Cause.
But what conceptions does he offer us? Nothing but that low
anthropomorphism which, unfortunately, he so often seems to treat as the
necessary result of Theism. It is again the dummy, helpless and deformed,
set up merely for the purpose of being knocked down.
It must once more be insisted on, that though man is indeed compelled to
conceive of God in human terms, and to speak of Him by epithets objectively
false, from their hopeless inadequacy, yet nevertheless the Christian
thinker declares that inadequacy in the strongest manner, and vehemently
rejects from his idea of God all terms distinctly implying infirmity or
limitation.
Now, Mr. Darwin speaks as if all who believe in the Almighty were compelled
to accept as really applicable to the Deity conceptions which affirm limits
and imperfections. Thus he says: "Can it be reasonably maintained that the
Creator intentionally ordered" "that certain fragments of rock should
assume certain shapes, so that the builder might erect his edifice?"
Why, surely every theist must maintain that in the first foundation of the
universe--the primary and absolute creation--God saw and knew every purpose
which every atom and particle of matter should ever subserve in all suns
and systems, and throughout all coming æons of time. It is almost
incredible, but nevertheless it seems necessary to think that the
difficulty thus proposed rests on a sort of notion that amidst the
boundless profusion of nature there is too much for God to superintend;
that the number of objects is too great for an infinite and {259}
_omnipresent_ being to attend singly to each and all in their due
proportions and needs! In the same way Mr. Darwin asks whether God can have
ordered the race variations referred to in the passage last quoted, for the
considerations therein mentioned. To this it may be at once replied that
even man often has _several_ distinct intentions and motives for a _single_
action, and the theist has no difficulty in supposing that, out of an
infinite number of motives, the motive mentioned in each case may have been
an exceedingly subordinate one. The theist, though properly attributing to
God what, for want of a better term, he calls "purpose" and "design," yet
affirms that the limitations of human purposes and motives are by no means
applicable to the Divine "purposes." Out of many, say a thousand million,
reasons for the institution of the laws of the physical universe, some few
are to a certain extent conceivable by us; and amongst these the benefits,
material and moral, accruing from them to men, and to each individual man
in every circumstance of his life, play a certain, perhaps a very
subordinate, part.[263] As Baden Powell observes, "How can we {260}
undertake to affirm, amid all the possibilities of things of which we
confessedly know so little, that a thousand ends and purposes may not be
answered, because we can trace none, or even imagine none, which seem to
our short-sighted faculties to be answered in these particular
arrangements?"[264]
The objection to the bull-dog's ferocity in connexion with "man's brutal
sport" opens up the familiar but vast question of the existence of evil, a
problem the discussion of which would be out of place here. Considering,
however, the very great stress which is laid in the present day on the
subject of animal suffering by so many amiable and excellent people, one or
two remarks on that matter may not be superfluous. To those who accept the
belief in God, the soul and moral responsibility; and recognize the full
results of that acceptance--to such, physical suffering and moral evil are
simply incommensurable. To them the placing of non-moral beings in the same
scale with moral agents will be utterly unendurable. But even considering
physical pain only, all must admit that this depends greatly on the mental
condition of the sufferer. Only during consciousness does it exist, and
only in the most highly-organized men does it reach its acme. The Author
has been assured that lower races of men appear less keenly sensitive to
physical pain than do more cultivated and refined human beings. Thus only
in man can there really be any intense degree of suffering, because only in
him is there that intellectual recollection of past moments and that
anticipation of future ones, which constitute in great part the bitterness
of suffering.[265] The momentary pang, the present pain, which beasts
endure, though real enough, is yet, doubtless, not to be compared as {261}
to its intensity with the suffering which is produced in man through his
high prerogative of self-consciousness.[266]
As to the "beneficial lines" (of Dr. Asa Gray, before referred to), some of
the facts noticed in the preceding chapters seem to point very decidedly in
that direction, but all must admit that the actual existing outcome is far
more "beneficial" than the reverse. The natural universe has resulted in
the development of an unmistakable harmony and beauty, and in a decided
preponderance of good and of happiness over their opposites.
Even if "laws of nature" did appear, on the theistic hypothesis, to be
"superfluous" (which it is by no means intended here to admit), it would be
nothing less than puerile to prefer rejecting the hypothesis to conceiving
that the appearance of superfluity was probably due to human ignorance; and
this especially might be expected from naturalists to whom the
interdependence of nature and the harmony and utility of obscure phenomena
are becoming continually more clear, as, _e.g._, the structure of orchids
to their illustrious expositor.
Having now cleared the ground somewhat, we may turn to the question what
bearing Christian dogma has upon evolution, and whether Christians, as
such, need take up any definite attitude concerning it.
As has been said, it is plain that physical science and "evolution" _can_
have nothing whatever to do with absolute or primary creation. The Rev.
Baden Powell well expresses this, saying: "Science demonstrates incessant
past changes, and dimly points to yet earlier links in a more vast series
of development of material existence; but the idea of a _beginning_, or of
_creation_, in the sense of the original operation of the Divine volition
to constitute nature and matter, is beyond the province of physical {262}
philosophy."[267]
With secondary or derivative creation, physical science is also incapable
of conflict; for the objections drawn by some writers seemingly from
physical science, are, as has been already argued, rather metaphysical than
physical.
Derivative creation is not a supernatural act, but is simply the Divine
action by and through natural laws. To recognize such action in such laws
is a religious mode of regarding phenomena, which a consistent theist must
necessarily accept, and which an atheistic believer must similarly reject.
But this conception, if deemed superfluous by any naturalist, can never be
shown to be _false_ by any investigations concerning natural laws, the
constant action of which it presupposes.
The conflict has arisen through a misunderstanding. Some have supposed that
by "creation" was necessarily meant either primary, that is, absolute
creation, or, at least, some supernatural action; they have therefore
opposed the dogma of "creation" in the imagined interest of physical
science.
Others have supposed that by "evolution" was necessarily meant a denial of
Divine action, a negation of the providence of God. They have therefore
combated the theory of "evolution" in the imagined interest of religion.
It appears plain then that Christian thinkers are perfectly free to accept
the general evolution theory. But are there any theological authorities to
justify this view of the matter?
Now, considering how extremely recent are these biological speculations, it
might hardly be expected _a priori_ that writers of earlier ages should
have given expression to doctrines harmonizing in any degree with such very
modern views,[268] nevertheless such most certainly is the case, and {263}
it would be easy to give numerous examples. It will be better, however,
only to cite one or two authorities of weight. Now, perhaps no writer {264}
of the earlier Christian ages could be quoted whose authority is more
generally recognized than that of St. Augustin. The same may be said of the
mediæval period, for St. Thomas Aquinas; and, since the movement of Luther,
Suarez may be taken as a writer widely venerated as an authority and one
whose orthodoxy has never been questioned.
It must be borne in mind that for a considerable time after even the last
of these writers no one had disputed the generally received view as to the
small age of the world or at least of the kinds of animals and plants
inhabiting it. It becomes therefore much more striking if views formed
under such a condition of opinion are found to harmonize with modern ideas
regarding "Creation" and organic life.
Now St. Augustin insists in a very remarkable manner on the merely
derivative sense in which God's creation of organic forms is to be
understood; that is, that God created them by conferring on the material
world the power to evolve them under suitable conditions. He says in his
book on Genesis:[269] "Terrestria animalia, tanquam ex ultimo elemento
mundi ultima; nihilominus _potentialiter_, quorum numeros tempus postea
visibiliter explicaret."
Again he says:--
"Sicut autem in ipso grano invisibiliter erant omnia simul, quæ per tempora
in arborem surgerent; ita ipse mundus cogitandus est, cum Deus _simul omnia
creavit_, habuisse simul omnia quæ in illo et cum illo facta sunt quando
factus est dies; non solum coelum cum sole et lunâ et sideribus ... ; sed
etiam illa quæ aqua et terra produxit potentialiter atque causaliter,
priusquam per temporum moras ita exorirentur, quomodo nobis jam nota sunt
in eis operibus, quæ Deus usque nunc operatur."[270]
"Omnium quippe rerum quæ corporaliter visibiliterque nascuntur, {265}
occulta quædam semina in istis corporeis mundi hujus elementis
latent."[271]
And again: "Ista quippe originaliter ac primordialiter in quadam textura
elementorum cuncta jam creata sunt; sed acceptis opportunitatibus
prodeunt."[272]
St. Thomas Aquinas, as was said in the first chapter, quotes with approval
the saying of St. Augustin that in the first institution of nature we do
not look for _Miracles_, but for the _laws of Nature_: "In prima
institutione naturæ non quæritur miraculum, sed quid natura rerum habeat,
ut Augustinus dicit."[273]
Again, he quotes with approval St. Augustin's assertion that the kinds were
created only derivatively, "_potentialiter tantum_."[274]
Also he says, "In prima autem rerum institutione fuit principium activum
verbum Dei, quod de materia elementari produxit animalia, vel in actu vel
_virtute_, secundum Aug. lib. 5 de Gen. ad lit. c. 5."[275]
Speaking of "kinds" (in scholastic phraseology "substantial forms") latent
in matter, he says: "Quas quidam posuerunt non incipere per actionem naturæ
sed prius in materia exstitisse, ponentes latitationem formarum. Et hoc
accidit eis ex ignorantia materiæ, quia nesciebant distinguere inter
potentiam et actum. Quia enim formæ præexistunt eas simpliciter
præexistere."[276]
Also Cornelius à Lapide[277] contends that at least certain animals were
not absolutely, but only derivatively created, saying of them, "Non fuerunt
creata formaliter, sed potentialiter."
As to Suarez, it will be enough to refer to Disp. xv., 2, n. 9, p. 508, t.
i. Edition _Vives_, Paris; also Nos. 13--15, and many other references{266}
to the same effect could easily be given, but these may suffice.
It is then evident that ancient and most venerable theological authorities
distinctly assert _derivative_ creation, and thus harmonize with all that
modern science can possibly require.
It may indeed truly be said with Roger Bacon, "The saints never condemned
many an opinion which the moderns think ought to be condemned."[278]
The various extracts given show clearly how far "evolution" is from any
necessary opposition to the most orthodox theology. The same may be said of
spontaneous generation. The most recent form of it, lately advocated by Dr.
H. Charlton Bastian,[279] teaches that matter exists in two different
forms, the crystalline (or statical) and the colloidal (or dynamical)
conditions. It also teaches that colloidal matter, when exposed to certain
conditions, presents the phenomena of life, and that it can be formed from
crystalline matter, and thus that the _prima materia_ of which these are
diverse forms contains potentially all the multitudinous kinds of animal
and vegetable existence. This theory moreover harmonizes well with the
views here advocated, for just as crystalline matter builds itself, under
suitable conditions, along _certain definite lines_, so analogously
colloidal matter has _its definite lines and directions_ of development. It
is not collected in haphazard, accidental aggregations, but evolves
according to its proper laws and special properties.
The perfect orthodoxy of these views is unquestionable. Nothing is plainer
from the venerable writers quoted, as well as from a mass of other {267}
authorities, than that "the supernatural" is not to be looked for or
expected in the sphere of mere nature. For this statement there is a
general _consensus_ of theological authority.
The teaching which the Author has received is, that God is indeed
inscrutable and incomprehensible to us from the infinity of His attributes,
so that our minds can, as it were, only take in, in a most fragmentary and
indistinct manner (as through a glass darkly), dim conceptions of
infinitesimal portions of His inconceivable perfection. In this way the
partial glimpses obtained by us in different modes differ from each other;
not that God is anything but the most perfect unity, but that apparently
conflicting views arise from our inability to apprehend Him, except in this
imperfect manner, _i.e._ by successive slight approximations along
different lines of approach. Sir William Hamilton has said,[280] "Nature
conceals God, and man reveals Him." It is not, according to the teaching
spoken of, exactly thus; but rather that physical nature reveals to us one
side, one aspect of the Deity, while the moral and religious worlds bring
us in contact with another, and at first, to our apprehension, a very
different one. The difference and discrepancy, however, which is at first
felt, is soon seen to proceed not from the reason but from a want of
flexibility in the imagination. This want is far from surprising. Not only
may a man naturally be expected to be an adept in his own art, but at the
same time to show an incapacity for a very different mode of activity.[281]
We rarely find an artist who takes much interest in jurisprudence, or {268}
a prizefighter who is an acute metaphysician. Nay, more than this, a
positive distaste may grow up, which, in the intellectual order, may amount
to a spontaneous and unreasoning disbelief in that which appears to be in
opposition to the more familiar concept, and this at all times. It is often
and truly said, "that past ages were pre-eminently credulous as compared
with our own, yet the difference is not so much in the amount of the
credulity, as in the direction which it takes."[282]
Dr. Newman observes: "Any one study, of whatever kind, exclusively pursued,
deadens in the mind the interest, nay the perception of any other. Thus
Cicero says, that Plato and Demosthenes, Aristotle and Isocrates, might
have respectively excelled in each other's province, but that each was
absorbed in his own. Specimens of this peculiarity occur every day. You can
hardly persuade some men to talk about anything but their own pursuit; they
refer the whole world to their own centre, and measure all matters by their
own rule, like the fisherman in the drama, whose eulogy on his deceased
lord was 'he was so fond of fish.'"[283]
The same author further says:[284] "When anything, which comes before us,
is very unlike what we commonly experience, we consider it on that account
untrue; not because it really shocks our reason as improbable, but because
it startles our imagination as strange. Now, revelation presents to us a
perfectly different aspect of the universe from that presented by the
sciences. The two informations are like the distinct subjects represented
by the lines of the same drawing, which, accordingly as they are read {269}
on their concave or convex side, exhibit to us now a group of trees with
branches and leaves, and now human faces." ... "While then reason and
revelation are consistent in fact, they often are inconsistent in
appearance; and this seeming discordance acts most keenly on the
imagination, and may suddenly expose a man to the temptation, and even
hurry him on to the commission of definite acts of unbelief, in which
reason itself really does not come into exercise at all."[285]
Thus we find in fact just that distinctness between the ideas derived from
physical science on the one hand and from religion on the other, which we
might _a priori_ expect if there exists that distinctness between the
natural and the miraculous which theological authorities lay down.
Assuming, for argument's sake, the truth of Christianity, it evidently has
not been the intention of its Author to make the evidence for it so plain
that its rejection would be the mark of intellectual incapacity. Conviction
is not forced upon men in the way that the knowledge that the government of
England is constitutional, or that Paris is the capital of France, is
forced upon all who choose to inquire into those subjects. The Christian
system is one which puts on the strain, as it were, _every_ faculty of
man's nature, and the intellect is not (any more than we should _a priori_
expect it to be) exempted from taking part in the probationary trial. A
moral element enters into the acceptance of that system.
And so with natural religion--with those ideas of the supernatural, viz.
God, Creation, and Morality, which are anterior to revelation and repose
upon reason. Here again it evidently has not been the intention of the
Creator to make the evidence of His existence so plain that its
non-recognition would be the mark of intellectual incapacity. {270}
Conviction, as to theism, is not forced upon men as is the conviction of
the existence of the sun at noon-day.[286] A moral element enters also
here, and the analogy there is in this respect between Christianity and
theism speaks eloquently of their primary derivation from one common
author.
Thus we might expect that it would be a vain task to seek anywhere in
nature for evidence of Divine action, such that no one could sanely deny
it. God will not allow Himself to be caught at the bottom of any man's
crucible, or yield Himself to the experiments of gross-minded and
irreverent inquirers. The natural, like the supernatural, revelation
appeals to _the whole_ of man's mental nature and not to the _reason
alone_.[287]
None, therefore, need feel disappointed that evidence of the direct action
of the first cause in merely natural phenomena ever eludes our grasp; for
assuredly those same phenomena will ever remain fundamentally inexplicable
by physical science alone.
There being then nothing in either authority or reason which makes
"evolution" repugnant to Christianity, is there anything in the Christian
doctrine of "Creation" which is repugnant to the theory of "evolution"?
Enough has been said as to the distinction between absolute and derivative
"creation." It remains to consider the successive "evolution" (Darwinian
and other) of "specific forms," in a theological light.
As to what "evolution" is, we cannot of course hope to explain it
completely, but it may be enough to define it as the manifestation to the
intellect, by means of sensible impressions, of some ideal entity (power,
principle, nature, or activity) which before that manifestation was in{271}
a latent, unrealized, and merely "potential" state--a state that is capable
of becoming realized, actual, or manifest, the requisite conditions being
supplied.
"Specific forms," kinds or species, are (as was said in the introductory
chapter) "peculiar congeries of characters or attributes, innate powers and
qualities, and a certain nature realized in individuals."
Thus, then, the "evolution of specific forms" means the actual
manifestation of special powers, or natures, which before were latent, in
such a successive manner that there is in some way a genetic relation
between posterior manifestations and those which preceded them.
On the special Darwinian hypothesis the manifestation of these forms is
determined simply by the survival of the fittest of many indefinite
variations.
On the hypothesis here advocated the manifestation is controlled and helped
by such survival, but depends on some unknown internal law or laws which
determine variation at special times and in special directions.
Professor Agassiz objects to the evolution theory, on the ground that
"species, genera, families, &c., exist as thoughts, individuals as
facts,"[288] and he offers the dilemma, "If species do not exist at all, as
the supporters of the transmutation theory maintain, how can they vary? and
if individuals alone exist, how can the differences which may be observed
among them prove the variability of species?"
But the supporter of "evolution" need only maintain that the several
"kinds" become manifested gradually by slight differences among the various
individual embodiments of one specific idea. He might reply to the dilemma
by saying, species do not exist _as species_ in the sense in which they are
said to vary (variation applying only to the concrete embodiments of {272}
the specific idea), and the evolution of species is demonstrated not by
individuals _as individuals_, but as embodiments of different specific
ideas.
Some persons seem to object to the term "creation" being applied to
evolution, because evolution is an "exceedingly slow and gradual process."
Now even if it were demonstrated that such is really the case, it may be
asked, what is "slow and gradual"? The terms are simply relative, and the
evolution of a specific form in ten thousand years would be instantaneous
to a being whose days were as hundreds of millions of years.
There are others again who are inclined absolutely to deny the existence of
species altogether, on the ground that their evolution is so gradual that
if we could see all the stages it would be impossible to say _when_ the
manifestation of the old specific form ceased and that of the new one
began. But surely it is no approach to a reason against the existence of a
thing that we cannot determine the exact moment of its first manifestation.
When watching "dissolving views," who can tell, whilst closely observing
the gradual changes, exactly at what moment a new picture, say St. Mark's,
Venice, can be said to have commenced its manifestation, or have begun to
dominate a preceding representation of "Dotheboys' Hall"? That, however, is
no reason for denying the complete difference between the two pictures and
the ideas they respectively embody.
The notion of a special nature, a peculiar innate power and activity--what
the scholastics called a "substantial form"--will be distasteful to many.
The objection to the notion seems, however, to be a futile one, for it is
absolutely impossible to altogether avoid such a conception and such an
assumption. If we refuse it to the individuals which embody the species, we
must admit it as regards their component parts--nay, even if we accept the
hypothesis of pangenesis, we are nevertheless compelled to attribute to
each gemmule that peculiar power of reproducing its own nature (its own
"substantial form"), with its special activity, and that remarkable {273}
power of annexing itself to certain other well-defined gemmules whose
nature it is also to plant themselves in a certain definite vicinity. So
that in each individual, instead of one such peculiar power and activity
dominating and controlling all the parts, you have an infinity of separate
powers and activities limited to the several minute component gemmules.
It is possible that in some minds, the notion may lurk that such powers are
simpler and easier to understand, because the bodies they affect are so
minute! This absurdity hardly bears stating. We can easily conceive a being
so small, that a gemmule would be to it as large as St. Paul's would be to
us.
Admitting then the existence of species, and of their successive evolution,
is there anything in these ideas hostile to Christian belief?
Writers such as Vogt and Buchner will of course contend that there is; but
naturalists, generally, assume that God acts in and by the various laws of
nature. And this is equivalent to admitting the doctrine of "derivative
creation." With very few exceptions, none deny such Divine concurrence.
Even "design" and "purpose" are recognized as quite compatible with
evolution, and even with the special "nebular" and Darwinian forms of it.
Professor Huxley well says,[289] "It is necessary to remark that there is a
wider teleology, which is not touched by the doctrine of evolution, but is
actually based upon the fundamental proposition of evolution." ... "The
teleological and the mechanical views of nature are not necessarily
mutually exclusive; on the contrary, the more purely a mechanist the
speculator is, the more firmly does he assume a primordial molecular
arrangement, of which all the phenomena of the universe are the
consequences; and the more completely thereby is he at the mercy of the
teleologist, who can always defy him to disprove that this primordial {274}
molecular arrangement was not intended to evolve the phenomena of the
universe."[290]
Professor Owen says, that natural evolution, through secondary causes, "by
means of slow physical and organic operations through long ages, is not the
less clearly recognizable as the act of all adaptive mind, because we have
abandoned the old error of supposing it to be the result[291] of a primary,
direct, and sudden act of creational construction." ... "The succession of
species by continuously operating law, is not necessarily a 'blind
operation.' Such law, however discerned in the properties and successions
of natural objects, intimates, nevertheless, a preconceived progress.
Organisms may be evolved in orderly succession, stage after stage, towards
a foreseen goal, and the broad features of the course may still show the
unmistakable impress of Divine volition."
Mr. Wallace[292] declares that the opponents of evolution present a less
elevated view of the Almighty. He says: "Why should we suppose the machine
too complicated to have been designed by the Creator so complete that it
would necessarily work out harmonious results? The theory of 'continual
interference' is a limitation of the Creator's power. It assumes that He
could not work by pure law in the organic, as He has done in the inorganic
world." Thus, then, there is not only no necessary antagonism between the
general theory of "evolution" and a Divine action, but the compatibility
between the two is recognized by naturalists who cannot be suspected of any
strong theological bias.
{275}
The very same may be said as to the special Darwinian form of the theory of
evolution.
It is true Mr. Darwin writes sometimes as if he thought that his theory
militated against even _derivative creation_.[293] This, however, there is
no doubt, was not really meant; and indeed, in the passage before quoted
and criticised, the possibility of the Divine ordination of each variation
is spoken of as a tenable view. He says ("Origin of Species," p. 569), "I
see no good reason why the views given in this volume should shock the
religious feelings of anyone;" and he speaks of life "having been
originally breathed by the Creator into a few forms or into one," which is
_more_ than the dogma of creation actually requires. We find then that no
_in_compatibility is asserted (by any scientific writers worthy of mention)
between "evolution" and the co-operation of the Divine will; while the same
"evolution" has been shown to be thoroughly acceptable to the most orthodox
theologians who repudiate the intrusion of the supernatural into the domain
of nature. A more complete harmony could scarcely be desired.
But if we may never hope to find, in physical nature, evidence of
supernatural action, what sort of action might we expect to find there,
looking at it from a theistic point of view? Surely an action the results
of which harmonize with man's reason,[294] which is orderly, which {276}
disaccords with the action of blind chance and with the "fortuitous
concourse of atoms" of Democritus; but at the same time an action which, as
to its modes, ever, in parts, and in ultimate analysis, eludes our grasp,
and the modes of which are different from those by which we should have
attempted to accomplish such ends.
Now, this is just what we _do_ find. The harmony, the beauty, and the order
of the physical universe are the themes of continual panegyrics on the part
of naturalists, and Mr. Darwin, as the Duke of Argyll remarks,[295]
"exhausts every form of words and of illustration by which intention or
mental purpose can be described"[296] when speaking of the wonderfully
complex adjustments to secure the fertilization of orchids. Also, we find
co-existing with this harmony a mode of proceeding so different from that
of man as (the direct supernatural action eluding us) to form a
stumbling-block to many in the way of their recognition of Divine action at
all: although nothing can be more inconsistent than to speak of the first
cause as utterly inscrutable and incomprehensible, and at the same time to
expect to find traces of a mode of action exactly similar to our own. It is
surely enough if the results harmonize on the whole and preponderatingly
with the rational, moral, and æsthetic instincts of man.
Mr. J. J. Murphy[297] has brought strongly forward the evidence of
"intelligence" throughout organic nature. He believes "that there is
something in organic progress which mere Natural Selection among
spontaneous variations will not account for," and that "this something is
that organizing intelligence which guides the action of the inorganic
forces, and forms structures which neither Natural Selection nor any other
unintelligent agency could form."
{277}
This intelligence, however, Mr. Murphy considers may be unconscious, a
conception which it is exceedingly difficult to understand, and which to
many minds appears to be little less than a contradiction in terms; the
very first condition of an intelligence being that, if it knows anything,
it should at least know its own existence.
Surely the evidence from physical facts agrees well with the overruling,
concurrent action of God in the order of nature; which is no miraculous
action, but the operation of laws which owe their foundation, institution,
and maintenance to an omniscient Creator of whose intelligence our own is a
feeble adumbration, inasmuch as it is created in the "image and likeness"
of its Maker.
This leads to the final consideration, a difficulty by no means to be
passed over in silence, namely the ORIGIN OF MAN. To the general theory of
Evolution, and to the special Darwinian form of it, no exception, it has
been shown, need be taken on the ground of orthodoxy. But in saying this,
it has not been meant to include the soul of man.
It is a generally received doctrine that the soul of every individual man
is absolutely created in the strict and primary sense of the word, that it
is produced by a direct or supernatural[298] act, and, of course, that by
such an act the soul of the first man was similarly created. It is
therefore important to inquire whether "evolution" conflicts with this
doctrine.
Now the two beliefs are in fact perfectly compatible, and that either on
the hypothesis--1. That man's body was created in a manner different in
kind from that by which the bodies of other animals were created; or 2.
That it was created in a similar manner to theirs.
One of the authors of the Darwinian theory, indeed, contends that even{278}
as regards man's body, an action took place different from that by which
brute forms were evolved. Mr. Wallace[299] considers that "Natural
Selection" alone could not have produced so large a brain in the savage, in
possessing which he is furnished with an organ beyond his needs. Also that
it could not have produced that peculiar distribution of hair, especially
the nakedness of the back, which is common to all races of men, nor the
peculiar construction of the feet and hands. He says,[300] after speaking
of the prehensile foot, common without a single exception to all the apes
and lemurs, "It is difficult to see why the prehensile power should have
been taken away" by the mere operation of Natural Selection. "It must
certainly have been useful in climbing, and the case of the baboons shows
that it is quite compatible with terrestrial locomotion. It may not be
compatible with perfectly easy erect locomotion; but, then, how can we
conceive that early man, _as an animal_, gained anything by purely erect
locomotion? Again, the hand of man contains latent capacities and powers
which are unused by savages, and must have been even less used by
palæolithic man and his still ruder predecessors. It has all the appearance
of an organ prepared for the use of civilized man, and one which was
required to render civilization possible." Again speaking of the "wonderful
power, range, flexibility, and sweetness of the musical sounds producible
by the human larynx," he adds, "The habits of savages give no indication of
how this faculty could have been developed by Natural Selection; because it
is never required or used by them. The singing of savages is a more or less
monotonous howling, and the females seldom sing at all. Savages certainly
never choose their wives for fine voices, but for rude health, and strength
and physical beauty. Sexual selection could not therefore have developed
this wonderful power, which only comes into play among civilized people. It
seems as if the organ had been prepared in anticipation of the future {279}
progress of man, since it contains latent capacities which are useless to
him in his earlier condition. The delicate correlations of structure that
give it such marvellous powers, could not therefore have been acquired by
means of Natural Selection."
[Illustration: FIBRES OF CORTI.]
To this may be added the no less wonderful faculty in the ear of
appreciating delicate musical tones, and the harmony of chords.
It matters not what part of the organ subserves this function, but it has
been supposed that it is ministered to by the fibres _of Corti_.[301] Now
it can hardly be contended that the preservation of any race of men in the
struggle for life could have depended on such an extreme delicacy and
refinement of the internal ear,[302]--a perfection only fully exercised in
the enjoyment and appreciation of the most exquisite musical performances.
Here, surely, we have an instance of an organ preformed, ready beforehand
for such action as could never by itself have been the cause of its
development,--the action having only been subsequent, not anterior. The
Author is not aware what may be the minute structure of the internal ear in
the highest apes, but if (as from analogy is probable) it is much as in
man, then _a fortiori_ we have an instance of _anticipatory_ development of
a most marked and unmistakable kind. And this is not all. There is no {280}
reason to suppose that any animal besides man appreciates musical
_harmony_. It is certain that no other one _produces_ it.
Mr. Wallace also urges objections drawn from the origin of some of man's
mental faculties, such as "the capacity to form ideal conceptions of space
and time, of eternity and infinity--the capacity for intense artistic
feelings of pleasure, in form, colour and composition--and for those
abstract notions of form and number which render geometry and arithmetic
possible," also from the origin of the moral sense.[303]
The validity of these objections is fully conceded by the Author of this
book, but he would push it much further, and contend (as has been now
repeatedly said), that another law, or other laws, than "Natural Selection"
have determined the evolution of _all_ organic forms, and of inorganic
forms also. And it must be contended that Mr. Wallace, in order to be quite
self-consistent, should arrive at the very same conclusion, inasmuch as he
is inclined to trace all phenomena to the action of superhuman WILL. He
says:[304] "If therefore we have traced one force, however minute, to an
origin in our own WILL, while we have no knowledge of any other primary
cause of force, it does not seem an improbable conclusion that all force
may be will-force; and thus, that the whole universe is not merely
dependent on, but actually _is_, the WILL of higher intelligences, or of
one Supreme Intelligence."
If there is really evidence, as Mr. Wallace believes, of the action of an
overruling intelligence in the evolution of the "human form divine;" if we
may go so far as this, then surely an analogous action may well be traced
in the production of the horse, the camel, or the dog, so largely
identified with human wants and requirements. And if from other than
physical considerations we may believe that such action, though
undemonstrable, has been and is; then (reflecting on sensible {281}
phenomena the theistic light derived from psychical facts) we may, in the
language of Mr. Wallace, "see indications of that power in facts which, by
themselves, would not serve to prove its existence."[305]
Mr. Murphy, as has been said before, finds it necessary to accept the
wide-spread action of "intelligence" as the agent by which _all_ organic
forms have been called forth from the inorganic. But all science tends to
unity, and this tendency makes it reasonable to extend to all physical
existences a mode of formation which we may have evidence for in any _one_
of them. It therefore makes it reasonable to extend, if possible, the very
same agency which we find operating in the field of biology, also to the
inorganic world. If on the grounds brought forward the action of
intelligence may be affirmed in the production of man's bodily structure,
it becomes probable _a priori_ that it may also be predicated of the
formative action by which has been produced the animals which minister to
him, and all organic life whatsoever. Nay more, it is then congruous to
expect analogous action in the development of crystalline and colloidal
structures, and in that of all chemical compositions, in geological
evolutions, and the formation not only of this earth, but of the solar
system and whole sidereal universe.
If such really be the direction in which physical science, philosophically
considered, points; if intelligence may thus be seen to preside over the
evolution of each system of worlds and the unfolding of every blade of
grass--this grand result harmonizes indeed with the teachings of faith that
God acts and concurs, in the natural order, with those laws of the material
universe which were not only instituted by His will, but are sustained by
His concurrence; and we are thus enabled to discern in the natural order,
however darkly, the Divine Author of nature--Him in whom "we live, and
move, and have our being."
But if this view is accepted, then it is no longer absolutely {282}
necessary to suppose that any action different in kind took place in the
production of man's body, from that which took place in the production of
the bodies of other animals, and of the whole material universe.
Of course, if it _can_ be demonstrated that that difference which Mr.
Wallace asserts really exists, it is plain that we then have to do with
facts not only harmonizing with religion, but, as it were, preaching and
proclaiming it.
It is not, however, necessary for Christianity that any such view should
prevail. Man, according to the old scholastic definition, is "a rational
animal" (_animal rationale_), and his animality is distinct in nature from
his rationality, though inseparably joined, during life, in one common
personality. This animal body must have had a different source from that of
the spiritual soul which informs it, from the distinctness of the two
orders to which those two existences severally belong.
Scripture seems plainly to indicate this when it says that "God made man
from the dust of the earth, and breathed into his nostrils the breath of
life." This is a plain and direct statement that man's _body_ was _not_
created in the primary and absolute sense of the word, but was evolved from
pre-existing material (symbolized by the term "dust of the earth"), and was
therefore only _derivatively created_, i.e. by the operation of secondary
laws. His _soul_, on the other hand, was created in quite a different way,
not by any pre-existing means, external to God himself, but by the direct
action of the Almighty, symbolized by the term "breathing:" the very form
adopted by Christ, when conferring the _supernatural_ powers and graces of
the Christian dispensation, and a form still daily used in the rites and
ceremonies of the Church.
That the first man should have had this double origin agrees with what we
now experience. For supposing each human soul to be directly and
immediately created, yet each human body is evolved by the ordinary
operation of natural physical laws. [Page 283]
Professor Flower in his Introductory Lecture[306] (p. 20) to his course of
Hunterian Lectures for 1870 well observes: "Whatever man's place may be,
either _in_ or _out_ of nature, whatever hopes, or fears or feelings about
himself or his race he may have, we all of us admit that these are quite
uninfluenced by our knowledge of the fact that each individual man comes
into the world by the ordinary processes of generation, according to the
same laws which apply to the development of all organic beings whatever,
that every part of him which can come under the scrutiny of the anatomist
or naturalist, has been evolved according to these regular laws from a
simple minute ovum, indistinguishable to our senses from that of any of the
inferior animals. If this be so--if man is what he is, notwithstanding the
corporeal mode of origin of the individual man, so he will assuredly be
neither less nor more than man, whatever may be shown regarding the
corporeal origin of the whole race, whether this was from the dust of the
earth, or by the modification of some pre-existing animal form."
Man is indeed compound, in him two distinct orders of being impinge and
mingle; and with this an origin from two concurrent modes of action is
congruous, and might be expected _a priori_. At the same time as the "soul"
is "the form of the body," the former might be expected to modify the
latter into a structure of harmony and beauty standing alone in the organic
world of nature. Also that, with the full perfection and beauty of that
soul, attained by the concurrent action of "Nature" and "Grace," a
character would be formed like nothing else which is visible in this world,
and having a mode of action different, inasmuch as complementary to all
inferior modes of action.
Something of this is evident even to those who approach the subject from
the point of view of physical science only. Thus Mr. Wallace observes,[307]
that on his view man is to be placed "apart, as not only the head and {284}
culminating point of the grand series of organic nature, but as in some
degree _a new and distinct order of being_.[308] From those infinitely
remote ages when the first rudiments of organic life appeared upon the
earth, every plant and every animal has been subject to one great law of
physical change. As the earth has gone through its grand cycles of
geological, climatal, and organic progress, every form of life has been
subject to its irresistible action, and has been continually but
imperceptibly moulded into such new shapes as would preserve their harmony
with the ever-changing universe. No living thing could escape this law of
its being; none (except, perhaps, the simplest and most rudimentary
organisms) could remain unchanged and live amid the universal change around
it."
"At length, however, there came into existence a being in whom that subtle
force we term _mind_, became of greater importance than his mere bodily
structure. Though with a naked and unprotected body, _this_ gave him
clothing against the varying inclemencies of the seasons. Though unable to
compete with the deer in swiftness, or with the wild bull in strength,
_this_ gave him weapons with which to capture or overcome both. Though less
capable than most other animals of living on the herbs and the fruits that
unaided nature supplies, this wonderful faculty taught him to govern and
direct nature to his own benefit, and make her produce food for him when
and where he pleased. From the moment when the first skin was used as a
covering; when the first rude spear was formed to assist in the chase; when
fire was first used to cook his food; when the first seed was sown or shoot
planted, a grand revolution was effected in nature, a revolution which in
all the previous ages of the earth's history had had no parallel, for a
being had arisen who was no longer necessarily subject to change with the
changing universe, a being who was in some degree superior to nature,
inasmuch as he knew how to control and regulate her action, and could {285}
keep himself in harmony with her, not by a change in body, but by an
advance in mind."
"On this view of his special attributes, we may admit 'that he is indeed a
being apart.' Man has not only escaped 'Natural Selection' himself, but he
is actually able to take away some of that power from nature which before
his appearance she universally exercised. We can anticipate the time when
the earth will produce only cultivated plants and domestic animals; when
man's selection shall have supplanted 'Natural Selection;' and when the
ocean will be the only domain in which that power can be exerted."
Baden Powell[309] observes on this subject: "The relation of the animal man
to the intellectual, moral, and spiritual man, resembles that of a crystal
slumbering in its native quarry to the same crystal mounted in the
polarizing apparatus of the philosopher. The difference is not in physical
nature, but in investing that nature with a new and higher application. Its
continuity with the material world remains the same, but a new relation is
developed in it, and it claims kindred with ethereal matter and with
celestial light."
This well expresses the distinction between the merely physical and the
hyperphysical natures of man, and the subsumption of the former into the
latter which dominates it.
The same author in speaking of man's moral and spiritual nature says,[310]
"The assertion in its very nature and essence refers wholly to a DIFFERENT
ORDER OF THINGS, apart from and transcending any material ideas
whatsoever." Again[311] he adds, "In proportion as man's _moral_
superiority is held to consist in attributes _not_ of a _material_ or
corporeal kind or origin, it can signify little how his _physical_ nature
may have originated."
Now physical science, as such, has nothing to do with the soul of man which
is hyperphysical. That such an entity exists, that the correlated {286}
physical forces go through their Protean transformations, have their
persistent ebb and flow outside of the world of WILL and SELF-CONSCIOUS
MORAL BEING, are propositions the proofs of which have no place in this
work. This at least may however be confidently affirmed, that no reach of
physical science in any coming century will ever approach to a
demonstration that countless modes of being, as different from each other
as are the force of gravitation and conscious maternal love, may not
co-exist. Two such modes are made known to us by our natural faculties
only: the physical, which includes the first of these examples; the
hyperphysical, which embraces the other. For those who accept revelation, a
third and a distinct mode of being and of action is also made known,
namely, the direct and immediate or, in the sense here given to the term,
the supernatural. An analogous relationship runs through and connects all
these modes of being and of action. The higher mode in each case employs
and makes use of the lower, the action of which it occasionally suspends or
alters, as gravity is suspended by electro-magnetic action, or the living
energy of an organic being restrains the inter-actions of the chemical
affinities belonging to its various constituents.
Thus conscious will controls and directs the exercise of the vital
functions according to desire, and moral consciousness tends to control
desire in obedience to higher dictates.[312] The action of living {287}
organisms depends upon and subsumes the laws of inorganic matter. Similarly
the actions of animal life depend upon and subsume the laws of organic
matter. In the same way the actions of a self-conscious moral agent, such
as man, depend upon and subsume the laws of animal life. When a part or the
whole series of these natural actions is altered or suspended by the
intervention of action of a still higher order, we have then a "miracle."
In this way we find a perfect harmony in the double nature of man, his
rationality making use of and subsuming his animality; his soul arising
from direct and immediate creation, and his body being formed at first (as
now in each separate individual) by derivative or secondary creation,
through natural laws. By such secondary creation, _i.e._ by natural laws,
for the most part as yet unknown but controlled by "Natural Selection," all
the various kinds of animals and plants have been manifested on this
planet. That Divine action has concurred and concurs in these laws we know
by deductions from our primary intuitions; and physical science, if unable
to demonstrate such action, is at least as impotent to disprove it.
Disjoined from these deductions, the phenomena of the universe present an
aspect devoid of all that appeals to the loftiest aspirations of man, that
which stimulates his efforts after goodness, and presents consolations for
unavoidable shortcomings. Conjoined with these same deductions, all the
harmony of physical nature and the constancy of its laws are preserved
unimpaired, while the reason, the conscience, and the æsthetic instincts
are alike gratified. We have thus a true reconciliation of science and
religion, in which each gains and neither loses, one being complementary to
the other.
Some apology is due to the reader for certain observations and arguments
which have been here advanced, and which have little in the shape of
novelty to recommend them. But after all, novelty can hardly be predicated
of the views here criticised and opposed. Some of these seem almost a {288}
return to the "fortuitous concourse of atoms" of Democritus, and even the
very theory of "Natural Selection" itself--a "survival of the fittest"--was
in part thought out not hundreds but _thousands_ of years ago. Opponents of
Aristotle maintained that by the accidental occurrence of combinations,
organisms have been preserved and perpetuated such as final causes, did
they exist, would have brought about, disadvantageous combinations or
variations being speedily exterminated. "For when the very same
combinations happened to be produced which the law of final causes would
have called into being, those combinations which proved to be advantageous
to the organism were preserved; while those which were not advantageous
perished, and still perished like the minotaurs and sphinxes of
Empedocles."[313]
In conclusion, the Author ventures to hope that this treatise may not be
deemed useless, but have contributed, however slightly, towards clearing
the way for peace and conciliation and for a more ready perception, of the
harmony which exists between those deductions from our primary intuitions
before alluded to, and the teachings of physical science, as far, that is,
as concerns the evolution of organic forms--_the genesis of species_.
The aim has been to support the doctrine that these species have been
evolved by ordinary _natural laws_ (for the most part unknown) controlled
by the _subordinate_ action of "Natural Selection," and at the same time to
remind some that there is and can be absolutely nothing in physical science
which forbids them to regard those natural laws as acting with the Divine
concurrence and in obedience to a creative fiat originally imposed on the
primeval Cosmos, "in the beginning," by its Creator, its Upholder, and its
Lord.
{289}
* * * * *
INDEX.
A.
Aard-Vark, 174.
Absolute creation, 252.
Acanthometræ, 186.
Acrodont teeth, 148.
Acts formally moral, 195.
Acts materially moral, 195.
Adductor muscles, 79.
Agassiz, Professor, 271.
Aged, care of, 192.
Aggregational theory, 163.
Algoa Bay, cat of, 98.
Allantois, 82.
Amazons, butterflies of, 85.
Amazons, cholera in the, 192.
American butterflies, 29.
American maize, 100.
American monkeys, 226.
Amiurus, 147.
Amphibia, 109.
Analogical relations, 157.
Ancon sheep, 100, 103, 227.
Andrew Murray, Mr., 83.
Angora cats, 175.
Animal's sufferings, 260.
Ankle bones, 158.
Annelids undergoing fission, 169, 211.
Annulosa, eye of, 76.
Anoplotherium, 109.
Anteater, 83.
Antechinus, 82.
Antenna, of orchid, 56.
Anthropomorphism, 258.
Ape's sexual characters, 49.
Apostles' Creed, 245.
Appendages of lobster, 161.
Appendages of Normandy pigs, 99.
Appendages of turkey, 100.
Appendix, vermiform, 83.
Appreciation of Mr. Darwin, 10.
Apteryx, 7, 70.
Aqueous humour, 76.
Aquinas, St. Thomas, 17, 263, 265.
Archegosaurus, 135.
Archeopteryx, 73.
Arcturus, 193.
Argyll, Duke of, 14, 276.
Aristotle, 288.
Armadillo, extinct kind, 110.
Arthritis, rheumatic, 183.
Artiodactyle foot, 109.
Asa Gray, Dr., 253, 255, 261.
Asceticism, 193.
Ascidians, placental structure, 81.
Assumptions of Mr. Darwin, 16.
Astronomical objections, 136.
Auditory organ, 74.
Augustin, St., 17, 263, 264.
Aurelius, Marcus, 206.
Avian limb, 106.
Avicularia, 80.
Axolotl, 165.
Aye-Aye, 107.
Aylesbury ducks, 234.
B.
Backbone, 135, 162.
Bacon, Roger, 266.
Baleen, 40.
Bamboo insect, 33.
Bandicoot, 67.
Bartlett, Mr. A. D., 126, 234.
Bartlett, Mr. E., 192.
Basil, St., 17.
Bastian, Dr. H. Charlton, 115, 219, 237, 266.
Bat, wing of, 64.
Bates, Mr., 29, 85, 87.
[Page 290]
Bats, 108.
Beaks, 83.
Beasts, sufferings of, 260.
Beauty of shell-fish, 54.
Bee orchid, 55.
Bird, wings of, 64.
Birds compared with reptiles, 70.
Bird's-head processes, 80.
Birds of Paradise, 90.
Birth of individual and species, 2.
Bivalves, 79.
Black sheep, 122.
Black-shouldered peacock, 100.
Bladebone, 70.
Blood-vessels, 182.
Blyth, Mr., 100, 181.
Bones of skull, 153.
Bonnet, M., 217.
Borwick, Mr., 198.
"Boots" of pigeons, 181.
Breathing, modified power of, 99.
Breeding of lions, 234.
Brill, 37.
Broccoli, variety of, 100.
Bryozoa, 81.
Buchner, Dr., 273.
Budd, Dr. W., 183.
Buffon, 217.
Bull-dog's instinct, 260.
Burt, Prof. Wilder, 180, 184.
Butterflies, 29.
Butterflies, Amazonian, 85.
Butterflies, American, 29.
Butterflies of Indian region, 83.
Butterflies, tails of, 85.
Butterfly, Leaf, 31.
C.
Cacotus, 149.
Cæcum, 83.
Calamaries, 77.
Cambrian deposits, 137.
Cape ant-eater, 174.
Care of aged, 192.
Carinate birds, 70.
Carnivora, 68.
Carnivorous dentition, 110.
Carp fishes, 146.
Carpal bones, 106, 178.
Carpenter, Dr., 115.
Carpus, 177, 178.
Cases of conscience, 201.
Cassowary, 70.
Catasetum, 56.
Causes of spread of Darwinism, 10.
Cebus, 226.
Celebes, butterflies of, 85.
Centetes, 148.
Centipede, 66, 159.
Cephalopoda, 74.
Ceroxylus laceratus, 36.
Cetacea, 42, 83, 105, 108, 174.
Chances against few individuals, 57.
Characinidæ, 146.
Cheirogaleus, 158.
Chetahs, 234.
Chickens, mortality of hybrids, 124.
Chioglossa, 165.
Chiromys, 107.
Cholera, 192.
Choroid, 76.
Chronic rheumatism, 183.
Circumcision, 212.
Clarias, 146.
Climate, effects of, 98.
Climbing plants, 107.
Clock-thinking illustration, 249.
Cobra, 50.
Cockle, 79.
Cod, 39.
Colloidal matter, 266.
Conceptions, symbolic, 251.
Connecticut footsteps, 131.
Connecting links, supposed, 107.
Conscience, cases of, 201.
Conscientious Papuan, 197.
Cope, Professor, 71, 130.
Coracoid, of birds and reptiles, 70.
Cornea, 77.
Cornelius à Lapide, 265.
Correlation, laws of, 173.
Corti, fibres of, 53, 279.
Coryanthes, 56.
Costa, M., 88.
Cranial segments, 172.
Creation, 245, 252.
Creator, 15, 252.
Creed, Apostles', 245.
Crocodile, 43.
Croll, Mr., 137.
Crustacea, 79, 160.
Cryptacanthus, 146.
Crystalline matter, 266.
Crystals of snow, 186.
Cuttle-fishes, 74, 75.
Cuvier, 109.
Cyprinoids, 146.
Cytheridea, 79.
[Page 291]
D.
Dana, Professor, 149.
Darwin, Mr. Charles, 2, 10, 12, 14-21, 23, 27, 34, 35, 43, 45, 47, 48,
55-57, 59, 65, 88, 94, 98-100, 107, 118-126, 129, 138, 142, 145, 149,
150, 181, 188-190, 196, 208, 209, 214-216, 218, 223, 233, 234, 252,
254, 258, 259, 275, 276.
Datura tatula, 101.
Delhi, days at, 98.
Delpino, Signor, 212, 213, 215.
Democritus, 217, 275, 288.
Density of air for breathing, 99.
Dentition, carnivorous, 110.
Derivation, 238.
Derivative creation, 252, 282.
Design, 259.
Devotion, 193.
Dibranchiata, 74.
Difficulties of problem of specific origin, 1.
Digits, supernumerary, 122, 181.
Digits, turtle's, 106.
Dimorphodon, 71.
Dinornis, 70.
Dinosauria, 71.
Diseased pelvis, 182.
Dissemination of seeds, 65.
Doris, 170.
Dotheboys' Hall, 272.
Dragon, the flying, 64, 158.
Dragon-fly, 77.
Droughts, 25.
Duck-billed platypus, 175.
Dugong, 41, 175.
Duke of Argyll, 14, 276.
Dyspepsia, 201.
E.
Ear, 74.
Ear, formation of, 51.
Early specialization, 111.
Echinodermata, 44.
Echinoidea, 44.
Echinops, 148.
Echinorhinus, 172.
Echinus, 43.
Economy, Fuegian political, 192.
Eczema, 183.
Edentata, 174.
Egyptian monuments, 138.
Elasmobranchs, 140.
Elbow and knee affections, 183.
Empedocles, 288.
Eocene ungulata, 110.
Eolis, 170.
Equus, 97.
Ericulus, 148.
Ethics, 188.
Eudes Deslongchamps, 99.
Eurypterida, 141, 171.
Eutropius, 147.
Everett, Rev. R., 98.
Evolution requires geometrical increase of time, 139.
Eye, 76.
Eye, formation of, 51.
Eye of trilobites, 135.
F.
Fabre, M., 46.
Feather-legged breeds, 181.
Feejeans, 199.
Fertilization of orchids, 55.
"Fiat justitia, ruat coelum," 195.
Fibres of Corti, 53, 279.
Final misery, 194.
Finger of Potto, 105.
Fish, flying, 64.
Fishes, fresh-water, 145.
Fishes, thoracic and jugular, 39, 140.
Fixity of position of limbs, 39.
Flat-fishes, 37, 166.
Flexibility of bodily organization, degrees of, 119.
Flexibility of mind, 267.
Flies, horned, 93.
Flight of spiders, 65.
Flounder, 37.
Flower, Professor, 163, 232, 283.
Fly, orchid, 55.
Flying-dragon, 64, 158.
Flying fish, 64.
Foetal teeth of whales, 7.
Food, effects on pigs, 99.
Footsteps of Connecticut, 131.
Foraminifera, 186.
Formally moral acts, 195.
Formation of eye and ear, 51.
Forms, substantial, 186, 272.
Four-gilled Cephalopods, 76.
Fowls, white silk, 122.
French theatrical audience, 198.
Fresh-water fishes, 145.
Frogs, Chilian and European, 149.
Fuego, Terra del, 192.
[Page 292]
G.
Galago, 158.
Galaxias, 147.
Galeus vulgaris, 172.
Galton, Mr. F., 97, 113, 228.
Gascoyen, Mr., 182.
Gavials, 43.
Gegenbaur, Prof., 176-178.
Gemmules, 208.
Generative system, its sensitiveness, 235.
Genesis of morals, 201.
Geographical distribution, 144.
Geographical distribution explained by Natural Selection, 6.
Geometrical increments of time, 139.
Geotria, 147.
Giraffe, neck of, 24.
Gizzard-like stomach, 83.
Glacial epoch, 150.
Glyptodon, 110.
Godron, Dr., 101.
Goose, its inflexibility, 119.
Göppert, Mr., 101.
Gould, Mr., 88.
Grasshopper, Great Shielded, 89.
Gray, Dr. Asa, 253, 255, 261.
Great Ant-eater, 83.
Great Salamander, 172.
Great Shielded Grasshopper, 89.
Greyhounds in Mexico, 99.
Greyhounds, time for evolution of, 138.
Guinea-fowl, 120.
Guinea-pig, 126.
Günther, Dr., 145, 146, 172.
H.
Hairless Dogs, 174, 175.
Hamilton, Sir Wm., 267.
Harmony, musical, 54, 279.
Heart in birds and reptiles, 158.
Hegel, 217.
Heliconidæ, 29.
Hell, 194.
Heptanchus, 172.
Herbert Spencer, Mr., 20, 28, 67, 72, 163-166, 168, 170-172, 184, 187,
202, 203, 205, 218, 228, 245, 246, 248, 251.
Hessian flies, 170.
Heterobranchus, 146.
Hewitt, Mr., 124, 181.
Hexanchus, 172.
Hipparion, 97, 134.
Homogeny, 158.
Homology, bilateral or lateral, 156, 164.
Homology, meaning of term, 7, 156.
Homology, serial, 159.
Homology, vertical, 165.
Homoplasy, 159.
Honey-suckers, 90.
Hood of cobra, 50.
Hook-billed ducks, 100.
Hooker, Dr., 150.
Horned flies, 93.
Horny plates, 40, 42.
Horny stomach, 83.
Human larynx, 54, 278.
Humphry, Professor, 163.
Hutton, Mr. R. Holt, 202, 203.
Huxley, Professor, 67-69, 71, 72, 95, 103, 109, 130, 131, 137, 141, 163,
172, 173, 231, 247, 273.
Hybrids, mortality of, 124.
Hydrocyonina, 146.
Hyperphysical action, 253.
Hyrax, 179.
I.
Ichthyopsida, 109.
Ichthyosaurus, 78, 106, 132, 177.
Ichthyosis, 183.
Iguanodon, 71.
Illegitimate symbolic conceptions, 251.
Illustration by clock-thinking, 249.
Imaginal disks, 46, 170.
Implacental mammals, 67, 68.
Independent origins, 152.
Indian butterfly, 30.
Indian region's butterflies, 83.
Indians and cholera, 192.
Individual, meaning of word, 2.
Infirm, care of, 192.
Influence, local, 83.
Insect, walking-leaf, 35.
Insects, walking-stick and bamboo, 33.
Insectivora, 68.
Insectivorous mammals, 148.
Insectivorous teeth, 68.
Instinct of bull-dog, 260.
Intermediate forms, 128.
Intuitions, primary, 251.
Irregularities in blood-vessels, 182.
Isaria felina, 115.
[Page 293]
J.
Japanned Peacock, 100.
Jews, 212.
Joints of backbone, 157, 162.
Jugular fishes, 39, 141.
Julia Pastrana, 174.
K.
Kallima inachis, 31.
Kallima paralekta, 31.
Kangaroo, 42, 67.
Kowalewsky, 81.
Knee and elbow affections, 183.
Kölliker, Professor, 104.
L.
Labyrinthici, 146.
Labyrinthodon, 104, 134.
Lamarck, 3.
Lankester, Mr. Ray, 152, 158.
Larynx of kangaroo, 42.
Larynx of man, 54, 278.
Lateral homology, 164.
Laws of correlation, 173.
Leaf butterfly, 31.
Legitimate symbolic conceptions, 251.
Lens, 76.
Lepidosteus, 172.
Lepra, 183.
Lewes, Mr. G. H., 94, 212, 214, 216.
Lewis, St., 206.
Lewis XV., 206.
Lewis XVI., 206.
Limb genesis, 176.
Limb muscles, 180.
Limbs, fixity of position of, 39.
Limbs of lobster, 161.
Links, supposed connecting, 107.
Lions, breeding, 234.
Lions, diseased pelvis, 182.
Llama, 109.
Local influences, 83.
Lobster, 160.
Long-tailed bird of Paradise, 91.
Lubbock, Sir John, 193, 204.
Lyell Sir, Charles, on dogs, 99, 106.
M.
Machairodus, 110.
Macrauchenia, 109.
Macropodidæ, 69.
Macroscelides, 68.
Madagascar, 148, 152.
Magnificent Bird of Paradise, 93.
Maize, American, 100.
Mammals, 67.
Mammary gland of kangaroo, 42.
Mammary gland, origin of, 47.
Man, origin of, 277.
Man reveals God, 267.
Man, voice of, 54.
Manatee, 41, 175.
Manchamp breed of sheep, 100.
Manis, 175.
Man's larynx, 54.
Many simultaneous modifications, 57.
Marcus Aurelius, 206.
Martineau, Mr. James, 200, 245.
Mastacembelus, 145.
Materially moral acts, 195.
Matter, crystalline and colloidal, 266.
Meaning of word "individual," 2.
Meaning of word "species," 2.
Mechanical theory of spine, 164.
Mediterranean oyster, 88, 98.
Meehan, Mr., 88.
Mexico, dogs in, 99.
Mill, John Stuart, 15, 189, 193, 194.
Mimicry, 8, 29.
Miracle, 287.
Molars, 111.
Mole, 176.
Molière, 230.
Mombas, cats at, 98.
Monkeys, American, 226.
Monster proboscis, 123.
Moral acts, 195.
Mordacia, 147.
Murphy, Mr. J. J., 52, 53, 76, 103, 114, 115, 137, 185, 221, 276, 281.
Murray, Mr. Andrew, 83.
Mus delicatulus, 82.
Muscles of limbs, 180.
Mussel, 79.
Myrmecophaga, 83.
N.
Nasalis, Semnopithecus, 139.
Nathusius, 99.
Natural Selection, shortly stated, 5.
Naudin, M. C., 101.
Nautilus, 76.
Nebular evolution, 273.
Neck of giraffe, 24.
Newman, the Rev. Dr., 260, 268, 270, 286.
[Page 294]
New Zealand crustacea, 149.
New Zealand fishes, 147.
Niata cattle, 100.
Nile fishes, 146.
Normandy pig, 99.
North American fish, 147
Nycticebus, 179.
O.
Object of book, 5.
Objections from astronomy, 136.
Octopods, 77.
Offensive remarks of Prof. Vogt, 13.
Old, care of the, 192.
Old Fuegian women, 192.
Omygena exigua, 115.
Ophiocephalus, 146.
Optic lobes of pterodactyls, 71.
Orchids, 92.
Orchids, Bee, &c., 55.
Organ of hearing, 74.
Organ of sight, 76.
Organic polarities, 185.
Origin of man, 277.
Orioles, 90.
Ornithoptera, 84.
Ornithorhynchus, 175.
Orthoceratidæ, 170.
Orycteropus, 174.
Ostracods, 79.
Ostrich, 70.
Otoliths, 74.
Outlines of butterflies' wings, 86.
Owen, Professor, 74, 102, 123, 217, 238, 274.
Oyster of Mediterranean, 88, 98.
Oysters, 79.
P.
Paget, Mr. J., 182.
Palæotherium, 109.
Pallas, 125.
Pangenesis, 19, 208.
Pangolin, 175.
Papilio Hospiton, 85.
Papilio Machaon, 85.
Papilio Ulysses, 84.
Papilionidæ, 83.
Papuan morals, 197, 198.
Parthenogenesis, 217.
Passiflora gracilis, 107.
Pastrana, Julia, 174.
Pathological polarities, 184.
Pavo nigripennis, 100.
Peacock, black shouldered, 100.
Peacock, inflexibility of, 119.
Pedicellariæ, 44.
Pelvis, diseased, 182.
Pendulous appendages of turkey, 100.
Perameles, 68.
Periophthalmus, 146.
Perissodactyle ungulates, 109.
Permian, jugular fish, 141.
Perodicticus, 105, 179.
Phalangers, 67.
Phasmidæ, 89.
Phyllopods, 79.
Physical actions, 253.
"Physiological units," 168, 218.
Pigeons' "boots," 181.
Placental mammals, 67.
Placental reproduction, 81.
Plants, tendrils of, 107.
Plates of baleen, 40.
Platypus, 175.
Pleiades, 193.
Plesiosaurus, 106, 133, 178.
Pleurodont dentition, 148.
Pleuronectidæ, 37, 166.
Plotosus, 147.
Poisoning apparatus, 66.
Poisonous serpents, 50.
Polarities, organic, 184, 185.
Political economy, Fuegian, 192.
Polyzoa, 80, 81.
Pompadour, Madame de, 206.
Poppy, variety of, 101.
Porcupine, 175.
Porto Santo rabbit, 100, 122.
Potto, 105, 179.
Pouched beasts, 67.
Powell, the Rev. Baden, 259, 261, 285.
Premolars, 111.
Prepotency, 124.
Primary intuitions, 251.
Primitive man, 204.
Problem of origin of kinds, 1.
Proboscis monkey, 139.
Proboscis of ungulates, 123.
Processes, bird's-head, 80.
Psettus, 146.
Psoriasis, 183.
Pterodactyles, compared with birds, 70.
Pterodactyles, wing of, 64.
Puccinia, 115.
Purpose, 259.
[Page 295]
Q.
Quasi-vertebral theory of skull, 172.
R.
Rabbit of Porto Santo, 100, 122.
Radial ossicle, 176.
Rarefied air, effect on dogs, 99.
Rattlesnake, 49, 50.
Red bird of Paradise, 92.
Relations, analogical, 157.
Relations, homological, 156.
Reptiles compared with birds, 70.
Retina, 76.
Retrieving, virtue a kind of, 189, 205.
Reversion, cases of, 122.
Rhea, 70.
Ribs of Cetacea and Sirenia, 41.
Ribs of flying-dragon, 64, 158.
Richardson's figures of pigs, 99.
Roger Bacon, 266.
Rudimentary structures, 7, 102.
S.
Sabre-toothed tiger, 110.
St. Augustin, 17, 263-265.
St. Basil, 17.
St. Hilaire, M., 179.
St. Thomas Aquinas, 17, 263, 265.
Salamander, great, 172.
Salter, Mr., 124.
Salvia officinalis, 213.
Salvia verticillata, 213.
Scapula of birds and reptiles, 70.
Schreber, 13.
Sclerotic, 76.
Scorpion, sting of, 66.
Seals, 83.
Sea squirts, 81.
Seeds, dissemination of, 65.
Seeley, Mr., on pterodactyles, 71.
Segmentation of skull, 172.
Segmentation of spine, 171.
Segments, similar, 160.
Self-existence, 252.
Semnopithecus, 139.
Sense, organ of, 51, 69, 74, 76.
Sensitiveness of generative system, 235.
Sepia, 77.
Serpents, poisonous, 50.
Sexual characters of apes, 49.
Sexual selection, 48.
Sharks, 83.
Shell-fish, beauty of, 54.
Shells of oysters, 88, 98.
Shielded grasshopper, 89.
Silurian strata, 140, 142.
Simultaneous modifications, 57.
Sirenia, 42
Sir John Lubbock, 198, 204.
Sir William Thomson, 136.
Sitaris, 46.
Six-shafted bird of Paradise, 90.
Skull bones, 153.
Skull segments, 172.
Sloth, windpipe of, 82.
Smithfield, wife-selling in, 198.
Snow, crystals of, 186.
Sole, 37.
Solenodon, 148.
Species, meaning of word, 2.
Spelerpes, 165.
Spencer, see Herbert Spencer.
Spider orchid, 55.
Spiders, flight of, 65.
Spine of Glyptodon, 110.
Spine, segmentation of, 172.
Squalidæ, 38.
Squilla, 160.
Sterility of hybrids, 125.
Stings, 66.
Straining action of baleen, 41.
Struthious birds, 70, 151.
Sturgeon, 171.
Suarez, 18, 263.
Substantial forms, 186, 272.
Sufferings of beasts, 260.
Supernatural action, 252.
Supernatural action not to be looked for in nature, 15.
Supernumerary digits, 122, 181.
Syllis, 169, 211.
Symbolic conceptions, 251.
Symmetrical diseases, 182.
Syphilitic deposits, 183.
T.
Tadpole's beak, 83.
Tails of butterflies, 85.
Tapir, 123, 134.
Tarsal bones, 159, 198.
Teeth of Cetacea, 83.
Teeth of Insectivora, 68.
Teeth of kangaroo and Macroscelides, 69.
Teeth of seals, 83.
Teeth of sharks, 83.
[Page 296]
Teleology and evolution compatible, 273.
Tendrils of climbing plants, 107.
Tenia echinococcus, 170.
Teratology, 173.
Tetragonopterina, 146.
Thomson, Sir William, 136.
Thoracic fishes, 39.
Thorax of crustaceans, 79.
Thylacine, 67.
Tierra del Fuego, 192.
Tiger, sabre-toothed, 110.
Time required for evolution, 128.
Tope, 172.
Trabeculæ cranii, 172.
Transitional forms, 128.
Transmutationism, 242.
Trevelyan, Sir J. Peacock, 100.
Trilobites, 135, 141, 171.
Tunicaries, 81.
Turbot, 37.
Turkey, effects of climate on, 100.
Turkish dog, 45.
Two-gilled cephalopods, 76.
Type, conformity to, 241.
U.
Umbilical vesicle, 82.
Ungulata, 25, 109.
Ungulata eocene, 110.
Units, physiological, 168, 218.
Unknowable, the, 245.
Upper Silurian strata, 140, 142.
Urotrichus, 68.
V.
Variability, different degrees of, 119.
Vermiform appendix, 83.
Vertebræ of skull, 172.
Vertebral column, 162, 171.
Vertebrate limbs, 38, 163.
Vertical homology, 165.
Vesicle, umbilical, 82.
"Vestiges of Creation," 3.
View here advocated, 5.
Vitreous humour, 76.
Vogt, Professor, 12, 273.
Voice of man, 54.
Voltaire, 230.
W.
Wagner, J. A., 13.
Wagner, Nicholas, 170.
Walking leaf, 35.
Walking-stick insect, 33.
Wallace, Mr. Alfred, 2, 10, 26, 29, 30, 32, 35, 36, 54, 83, 84, 87, 89,
90, 103, 117, 191, 197, 226, 274, 281-283.
Weaver fishes, 39.
Weitbrecht, 179.
Whale, foetal teeth of, 7.
Whale, mouth of, 40.
Whalebone, 40.
Whales, 78.
White silk fowls, 122.
Wife selling, 198.
Wild animals, their variability, 120.
Wilder, Professor Burt, 180, 184.
Windpipe, 82.
Wings of bats, birds, and pterodactyles, 64, 130.
Wings of birds, origin of, 106.
Wings of butterflies, outline of, 86.
Wings of flying-dragon, 64, 158.
Wings of humming-bird, 157.
Wings of humming-bird hawk moth, 157.
Wings of insects, 65.
Wombat, 83.
Women, old Fuegian, 192.
Worms undergoing fission, 169, 211.
Wyman, Dr. Jeffries, 185.
Y.
York Minster, a Fuegian, 197.
Z.
Zebras, 134.
Zoological Gardens, Superintendent of, 126.
R. CLAY, SONS, AND TAYLOR, PRINTERS, LONDON.
* * * * *
Notes
[1] In the last edition of the "Origin of Species" (1869) Mr. Darwin
himself admits that "Natural Selection" has not been the exclusive means of
modification, though he still contends it has been the most important one.
[2] See Mr. Wallace's recent work, entitled "Contributions to the Theory of
Natural Selection," where, at p. 302, it is very well and shortly stated.
[3] "Natural Selection" is happily so termed by Mr. Herbert Spencer in his
"Principles of Biology."
[4] Biology is the science of life. It contains zoology, or the science of
animals, and botany, or that of plants.
[5] For very interesting examples, see Mr. Wallace's "Malay Archipelago."
[6] See Müller's work, "Für Darwin," lately translated into English by Mr.
Dallas. Mr. Wallace also predicts the discovery, in Madagascar, of a
hawk-moth with an enormously long proboscis, and he does this on account of
the discovery there of an orchid with a nectary from ten to fourteen inches
in length. See _Quarterly Journal of Science_, October 1867, and "Natural
Selection," p. 275.
[7] "Lectures on Man," translated by the Anthropological Society, 1864, p.
229.
[8] Ibid. p. 378.
[9] See Fifth Edition, 1869, p. 579.
[10] _The Rambler_, March 1860, vol. xii. p. 372.
[11] "In primâ institutione naturæ non quæritur miraculum, sed quid natura
rerum habeat, ut Augustinus dicit, lib. ii. sup. Gen. ad lit. c. l." (St.
Thomas, Sum. I^æ. lxvii. 4, ad 3.)
[12] "Hexaem." Hom. ix. p. 81.
[13] Suarez, Metaphysica. Edition Vivés. Paris, 1868. Vol. I. Disputatio
xv. § 2.
[14] "Pangenesis" is the name of the new theory proposed by Mr. Darwin, in
order to account for various obscure physiological facts, such, _e.g._, as
the occasional reproduction, by individuals, of parts which they have lost;
the appearance in offspring of parental, and sometimes of remote ancestral,
characters, &c. It accounts for these phenomena by supposing that every
creature possesses countless indefinitely-minute organic atoms, termed
"gemmules," which atoms are supposed to be generated in every part of every
organ, to be in constant circulation about the body, and to have the power
of reproduction. Moreover, atoms from every part are supposed to be stored
in the generative products.
[15] "Animals and Plants under Domestication," vol. ii. p. 192.
[16] "Animals and Plants under Domestication," vol. ii. p. 414.
[17] "Origin of Species," 5th edit., 1869, p. 110.
[18] Ibid. p. 111.
[19] Ibid. p. 227.
[20] The order _Ungulata_ contains the hoofed beasts; that is, all oxen,
deer, antelopes, sheep, goats, camels, hogs, the hippopotamus, the
different kinds of rhinoceros, the tapirs, horses, asses, zebras, quaggas,
&c.
[21] The elephants of Africa and India, with their extinct allies,
constitute the order _Proboscidea_, and do not belong to the Ungulata.
[22] See "Natural Selection," pp. 60-75.
[23] "Principles of Biology," vol. i. p. 122.
[24] See "Natural Selection," chap. iii. p. 45.
[25] Loc. cit. p. 80.
[26] Ibid. p. 59.
[27] Loc. cit. p. 64.
[28] "Origin of Species," 5th edit. p. 104.
[29] "Animals and Plants under Domestication," vol. ii. p. 351.
[30] Loc. cit. pp. 109, 110.
[31] Heredity is the term used to denote the tendency which there is in
offspring to reproduce parental features.
[32] Loc. cit. p. 64.
[33] Loc. cit. p. 60.
[34] The term "Vertebrata" denotes that large group of animals which are
characterized by the possession of a spinal column, commonly known as the
"backbone." Such animals are ourselves, together with all beasts, birds,
reptiles, frogs, toads, and efts, and also fishes.
[35] It is hardly necessary to observe that these "sea-snakes" have no
relation to the often-talked-of "sea-serpent." They are small, venomous
reptiles, which abound in the Indian seas.
[36] "Origin of Species," 5th edit., 1869, p. 179.
[37] "Origin of Species," 5th edit., p. 532.
[38] Mr. A. D. Bartlett, of the Zoological Society, informs me that at
these periods female apes admit with perfect readiness the access of any
males of different species. To be sure this is in confinement; but the fact
is, I think, quite conclusive against any such sexual selection in a state
of nature as would account for the local coloration referred to.
[39] Mr. Darwin, in the last (fifth) edition of "Natural Selection," 1869,
p. 102, admits that all sexual differences are not to be attributed to the
agency of sexual selection, mentioning the wattle of carrier pigeons, tuft
of turkey-cock, &c. These characters, however, seem less inexplicable by
sexual selection than those given in the text.
[40] I am again indebted to the kindness of Mr. A. D. Bartlett, amongst
others. That gentleman informs me that, so far from any mental emotion
being produced in rabbits by the presence and movements of snakes, that he
has actually seen a male and female rabbit satisfy the sexual instinct in
that presence, a rabbit being seized by a snake when _in coitu_.
[41] "Habit and Intelligence," vol. i. p. 319.
[42] The reader may consult Huxley's "Lessons in Elementary Physiology," p.
204.
[43] "Natural Selection," p. 350.
[44] Bivalve shell-fish are creatures belonging to the oyster, scallop, and
cockle group, _i.e._ to the class Lamellibranchiata.
[45] The attempt has been made to explain these facts as owing to "manner
and symmetry of growth, and to colour being incidental on the chemical
nature of the constituents of the shell." But surely beauty depends on some
such matters in _all_ cases!
[46] It has been suggested in opposition to what is here said, that there
is no real resemblance, but that the likeness is "_fanciful!_" The denial,
however, of the fact of a resemblance which has struck so many observers,
reminds one of the French philosopher's estimate of facts hostile to his
theory--"Tant pis pour les faits!"
[47] Fifth Edition, p. 236.
[48] Mr. Smith, of the Entomological department of the British Museum, has
kindly informed me that the individuals intermediate in structure are very
few in number--not more than five per cent.--compared with the number of
distinctly differentiated individuals. Besides, in the Brazilian kinds
these intermediate forms are wanting.
[49] By accidental variations Mr. Darwin does not, of course, mean to imply
variations really due to "chance," but to utterly indeterminate
antecedents.
[50] "Origin of Species," 5th edition, p. 235.
[51] _I.e._ warm-blooded animals which suckle their young, such as apes,
bats, hoofed beasts, lions, dogs, bears, weasels, rats, squirrels,
armadillos, sloths, whales, porpoises, kangaroos, opossums, &c.
[52] "Journal of Anatomy and Physiology" (1868), vol. ii. p. 139.
[53] See "Ann. and Mag. of Nat. Hist." for August 1870, p. 140.
[54] See "Proceedings of the Royal Institution," vol. v. part iv. p. 278:
Report of a Lecture delivered February 7, 1868. Also "Quarterly Journal of
the Geological Society," February 1870: "Contributions to the Anatomy and
Taxonomy of the Dinosauria."
[55] "Proceedings of Geological Society," November 1869, p. 38.
[56] The archeopteryx of the oolite has the true carinate shoulder
structure.
[57] "Proceedings of the Royal Institution," vol. v. p. 279.
[58] This remark is made without prejudice to possible affinities in the
direction of the Ascidians,--an affinity which, if real, would be
irrelevant to the question here discussed.
[59] "Lectures on the Comp. Anat. of the Invertebrate Animals," 2nd edit.
1855, p. 619; and Todd's "Cyclopædia of Anatomy," vol. i. p. 554.
[60] See "Habit and Intelligence," vol. i. p. 321.
[61] A view recently propounded by Kowalewsky.
[62] "Natural Selection," p. 167.
[63] "Natural Selection," p. 173.
[64] Ibid. p. 177.
[65] "Malay Archipelago," vol. i. p. 439.
[66] "Natural Selection," p. 177.
[67] "Origin of Species," 5th edition, p. 166.
[68] Vol. ii. p. 280.
[69] See "Natural Selection," p. 64.
[70] The italics are not Mr. Wallace's.
[71] "Malay Archipelago," vol. ii. p. 150; and "Natural Selection," p. 104.
[72] See "Malay Archipelago," vol. ii. chap. xxxviii.
[73] Loc. cit. p. 314.
[74] _Fortnightly Review_, New Series, vol. iii (April 1868), p. 372.
[75] "Lay Sermons," p. 339.
[76] "Hereditary Genius, an Inquiry into its Laws," &c. By Francis Galton,
F.R.S. (London: Macmillan.)
[77] "Animals and Plants under Domestication," vol. i. p. 37.
[78] Ibid. p. 47.
[79] Ibid. p. 52.
[80] Carpenter's "Comparative Physiology," p. 987, quoted by Mr. J. J.
Murphy, "Habit and Intelligence," vol. i. p. 171.
[81] "Animals and Plants under Domestication," vol. i. p. 72.
[82] Ibid. p. 76.
[83] "Animals and Plants under Domestication," vol. i. p. 71.
[84] Ibid. p. 114.
[85] Quoted, Ibid. p. 274.
[86] Ibid. p. 324.
[87] Ibid. p. 322.
[88] Ibid. vol. ii. p. 414.
[89] Proc. Zool. Soc. of London, April 24, 1860.
[90] "Animals and Plants under Domestication," vol. i. p. 291.
[91] Extracted by J. J. Murphy, vol. i. p. 197, from the _Quarterly Journal
of Science_, of October 1867, p. 527.
[92] "Anatomy of Vertebrates," vol. iii. p. 795.
[93] Ibid. p. 807.
[94] "Animals and Plants under Domestication," vol. ii. p. 318.
[95] "Habit and Intelligence," vol. i. p. 344.
[96] See Dec. 2, 1869, vol. i. p. 132.
[97] "Über die Darwin'sche Schöpfungstheorie:" ein Vortrag, von Kölliker;
Leipzig, 1864.
[98] See "Lay Sermons," p. 342.
[99] "Anatomy of the Lemuroidea." By James Murie, M.D., and St. George
Mivart. Trans. Zool. Soc., March 1866, p. 91.
[100] "Principles of Geology," last edition, vol. i. p. 163.
[101] _Quarterly Journal of Science_, April 1866, pp. 257-8.
[102] "Habit and Intelligence," vol. i. p. 178.
[103] This animal belongs to the order Primates, which includes man, the
apes, and the lemurs. The lemurs are the lower kinds of the order, and
differ much from the apes. They have their head-quarters in the Island of
Madagascar. The aye-aye is a lemur, but it differs singularly from all its
congeners, and still more from all apes. In its dentition it strongly
approximates to the rodent (rat, squirrel, and guinea-pig) order, as it has
two cutting teeth above, and two below, growing from permanent pulps, and
in the adult condition has no canines.
[104] _North British Review_, New Series, vol. vii., March 1867, p. 282.
[105] "Habit and Intelligence," vol. i. p. 75.
[106] "Habit and Intelligence," vol. i. p. 202.
[107] "Comparative Physiology," p. 214, note.
[108] See _Nature_, June and July 1870, Nos. 35, 36, and 37, pp. 170, 193,
and 219.
[109] "Natural Selection," p. 293.
[110] "Animals and Plants under Domestication," vol. i. pp. 289-295.
[111] "Origin of Species," 5th edition, 1869, p. 45.
[112] Ibid. p. 13.
[113] "Animals and Plants under Domestication," vol. i. p. 115.
[114] Ibid. vol. i. p. 114.
[115] Ibid. vol. i. p. 243.
[116] Ibid. vol. ii. p. 361.
[117] Ibid. vol. ii. p. 16.
[118] "Animals and Plants under Domestication," vol. ii. p. 57.
[119] This has been shown by my late friend, Mr. H. N. Turner, jun., in an
excellent paper by him in the "Proceedings of the Zoological Society for
1849," p. 147. The untimely death, through a dissecting wound, of this most
promising young naturalist, was a very great loss to zoological science.
[120] "Animals and Plants under Domestication," vol. ii. p. 189.
[121] "Origin of Species," 5th edition, 1839, p. 115.
[122] Ibid. p. 322.
[123] Ibid. p. 314.
[124] "Animals and Plants under Domestication," vol. ii. p. 104.
[125] _North British Review_, New Series, vol. vii., March 1867, p. 317.
[126] "Origin of Species," 5th edition, 1869, p. 212.
[127] See also the _Popular Science Review_ for July 1868.
[128] A bird with a keeled breast-bone, such as almost all existing birds
possess.
[129] "Anatomy of Vertebrates," vol. iii. p. 792.
[130] Ibid. p. 793.
[131] As a tadpole is the _larval form_ of a frog.
[132] As Professor Huxley, with his characteristic candour, fully admitted
in his lecture on the Dinosauria before referred to.
[133] "Transactions of the Geological Society of Glasgow," vol. iii.
[134] "Origin of Species," 5th edition, p. 354.
[135] See his address to the Geological Society, on February 19, 1869.
[136] See _Nature_, vol. i. p. 399, February 17, 1870.
[137] Ibid. vol. i. p. 454.
[138] "Habit and Intelligence," vol. i. p. 344.
[139] "Habit and Intelligence," vol. i. p. 345.
[140] "Origin of Species," 5th edition, p. 353.
[141] "Origin of Species," 5th edition, p. 381.
[142] "Origin of Species," 5th edition, 1869, p. 463.
[143] See his Catalogue of Acanthopterygian Fishes in the British Museum,
vol. iii. p. 540.
[144] Proc. Zool. Soc. 1867, p. 102, and Ann. Mag. of Nat. Hist. vol. xx.
p. 110.
[145] See Catalogue, vol. iii. p. 469.
[146] Ibid. vol. v. p. 311.
[147] Ibid. p. 345.
[148] Ibid. p. 13.
[149] Ibid. p. 21.
[150] See Catalogue, vol. v. p. 24.
[151] Ibid. p. 52.
[152] Ibid. p. 109.
[153] Ibid. vol. vi. 208.
[154] Ibid. vol. viii. p. 507.
[155] Ibid. p. 509.
[156] Proc. Zool. Soc. 1868, p. 482
[157] "Origin of Species," 5th edition, 1869, p. 454.
[158] "Origin of Species," 5th edition, p. 459.
[159] See Ann. and Mag. of Nat. Hist., July 1870, p. 37.
[160] Professor Huxley's Lectures on the Elements of Comp. Anat. p. 184.
[161] For an enumeration of the more obvious homological relationships see
Ann. and Mag. of Nat. Hist. for August 1870, p. 118.
[162] See Ann. and Mag, of Nat. Hist., July 1870.
[163] Treatise on the Human Skeleton, 1858.
[164] Hunterian Lectures for 1864.
[165] Linnæan Transactions, vol. xxv. p. 395, 1866.
[166] Hunterian Lectures for 1870, and Journal of Anat. for May 1870.
[167] See a Paper on the "Axial Skeleton of the Urodela," in Proc. Zool.
Soc. 1870, p. 266.
[168] Just as Button's superfluous lament over the unfortunate organization
of the sloth has been shown, by the increase of our knowledge, to have been
uncalled for and absurd, so other supposed instances of non-adaptation
will, no doubt, similarly disappear. Mr. Darwin, in his "Origin of
Species," 5th edition, p. 220, speaks of a woodpecker (_Colaptes
campestris_) as having an organization quite at variance with its habits,
and as never climbing a tree, though possessed of the special arboreal
structure of other woodpeckers. It now appears, however, from the
observations of Mr. W. H. Hudson, C.M.Z.S., that its habits are in harmony
with its structure. See Mr. Hudson's third letter to the Zoological
Society, published in the Proceedings of that Society for March 24, 1870,
p. 159.
[169] Dr. Cobbold has informed the Author that he has never observed a
planaria divide spontaneously, and he is sceptical as to that process
taking place at all. Dr. H. Charlton Bastian has also stated that, in spite
of much observation, he has never seen the process in _vorticella_.
[170] Professor Huxley's Hunterian Lecture, March 16, 1868.
[171] Ibid. March 18.
[172] "Principles of Biology," vol. ii. p. 105.
[173] "Principles of Biology," vol. ii. p. 203.
[174] Quoted by H. Stannius in his "Handbuch der Anatomie der
Wirbelthiere," Zweite Auflage, Erstes Buch, § 7, p. 17.
[175] In his last Hunterian Course of Lectures, 1869.
[176] "The Science of Abnormal Forms."
[177] "Animals and Plants under Domestication," vol. ii. p. 322; and
"Origin of Species," 5th edition, 1869, p. 178.
[178] A remarkable woman exhibited in London a few years ago.
[179] "Animals and Plants under Domestication," vol. ii. p. 328.
[180] "Ueber das Gliedmaassenskelet der Enaliosaurier, Jenaischen
Zeitschrift," Bd. v. Heft 3, Taf. xiii.
[181] In his work on the Carpus and Tarsus.
[182] An excellent specimen displaying this resemblance is preserved in the
Museum of the Royal College of Surgeons.
[183] Phil. Trans. 1867, p. 353.
[184] Proc. Zool. Soc. 1865, p. 255.
[185] Ibid. p. 351.
[186] "Hist. Générale des Anomalies," t. i. p. 228. Bruxelles, 1837.
[187] Nov. Comment. Petrop. t. ix. p. 269.
[188] Read on June 2, 1868, before the Massachusetts Medical Society. See
vol. ii. No. 3.
[189] "Animals and Plants under Domestication," vol. ii. p. 322.
[190] "Lectures on Surgical Pathology," 1853, vol. i. p. 18.
[191] "Lectures on Surgical Pathology," 1853, vol. i. p. 22.
[192] See "Medico-Chirurgical Transactions," vol. xxv. (or vii. of 2nd
series), 1842, p. 100, Pl. III.
[193] Med.-Chirurg. Trans, vol. xxv. (or vii. of 2nd series), 1842, p. 122.
[194] See _Boston Medical and Surgical Journal_ for April 5, 1866, vol.
lxxiv. p. 189.
[195] "Principles of Biology," vol. i. p. 180.
[196] See the "Proceedings of the Boston Society of Natural History," vol.
xi. June 5, 1867.
[197] "Habit and Intelligence," vol. i. p. 75.
[198] Ibid. p. 112.
[199] Ibid. p. 170.
[200] "Habit and Intelligence," vol. i. p. 229.
[201] It is hardly necessary to say that the Author does not mean that
there is, in addition to a real objective crystal, another real, objective
separate thing beside it, namely the "force" directing it. All that is
meant is that the action of the crystal in crystallizing must be _ideally_
separated from the crystal itself, not that it is _really_ separate.
[202] "Origin of Species," 5th edition, 1869, p. 577.
[203] Vol. ii. p. 122.
[204] "Animals and Plants under Domestication," vol. i p. 295.
[205] "Natural Selection," p. 350.
[206] "Animals and Plants under Domestication," vol. ii.
[207] See 2nd edition, vol. i. p. 214.
[208] Page 103.
[209] I have not the merit of having noticed this inconsistency; it was
pointed out to me by my friend the Rev. W. W. Roberts.
[210] Vol. i. p. 215.
[211] "Malay Archipelago," vol. ii. p. 365.
[212] "The Origin of Civilization and the Primitive Condition of Man," p.
261. Longmans, 1870.
[213] "Primitive Man," p. 248.
[214] "Fiji and the Fijians," vol. i. p. 183.
[215] "Essays," Second Series, vol. ii. p. 13.
[216] See No. 117, July 1869, p. 272.
[217] _Macmillan's Magazine_, No. 117, July 1869.
[218] "Animals and Plants under Domestication," vol. ii. p. 403.
[219] Ibid. p. 366.
[220] "Animals and Plants under Domestication," vol. ii. p. 402.
[221] See _Fortnightly Review_, New Series, vol. iii. April 1868, p. 352.
[222] This appeared in the _Rivista Contemporanea Nazionale Italiana_, and
was translated and given to the English public in _Scientific Opinion_ for
September 29, October 6, and October 13, 1869, pp. 365, 391, and 407.
[223] See _Scientific Opinion_, of October 13, 1869, p. 407.
[224] See _Scientific Opinion_ of September 29, 1869, p. 366.
[225] _Fortnightly Review_, New Series, vol. iii. April 1868, p. 508.
[226] _Scientific Opinion_, of October 13, 1869, p. 408.
[227] _Fortnightly Review_, New Series, vol. iii. April 1868, p. 509.
[228] "Histoire Naturelle, générale et particulière," tome ii. 1749, p.
327. "Ces liqueurs séminales sont toutes deux un extrait de toutes les
parties du corps," &c.
[229] See _Nature_, March 3, 1870, p. 454. Mr. Wallace says (referring to
Mr. Croll's paper in the _Phil. Mag._), "As we are now, and have been for
60,000 years, in a period of low eccentricity, _the rate of change of
species during that time may be no measure of the rate that has generally
obtained in past geological epochs_."
[230] "Habit and Intelligence," vol. i. p. 344.
[231] If anyone were to contend that beside the opium there existed a real
distinct objective entity, "its soporific virtue," he would be open to
ridicule indeed. But the constitution of our minds is such that we cannot
but distinguish ideally a thing from its even essential attributes and
qualities. The joke is sufficiently amusing, however, regarded as the
solemn enunciation of a mere truism.
[232] Noticed by Professor Owen in his "Archetype," p. 76. Recently it has
been attempted to discredit Darwinism in France by speaking of it as "_de
la science mousseuse!_"
[233] "Lay Sermons," p. 342.
[234] Introductory Lecture of February 14, 1870, pp. 24-30, Figs. 1-4.
(Churchill and Sons.)
[235] See especially "Animals and Plants under Domestication," vol. ii.
chap. xviii.
[236] "Origin of Species," 5th edition, pp. 323, 324.
[237] "Animals and Plants under Domestication," vol. ii. p. 2.
[238] Ibid. p. 25.
[239] Ibid. p. 151.
[240] Ibid. p. 157.
[241] Ibid. p. 158.
[242] "Animals and Plants under Domestication," vol. i. p. 291.
[243] Though hardly necessary, it may be well to remark that the views here
advocated in no way depend upon the truth of the doctrine of Spontaneous
Generation.
[244] Vol. iii. p. 808.
[245] This is hardly an exact representation of Mr. Darwin's view. On his
theory, if a favourable variation happens to arise (the external
circumstances remaining the same), it will yet be preserved.
[246] See 2nd edition, p. 113.
[247] "Essays, Philosophical and Theological," Trübner and Co., First
Series, 1866, p. 190. "Every relative disability may be read two ways. A
disqualification in the nature of thought for knowing _x_ is, from the
other side, a disqualification in the nature of _x_ from being known. To
say then that the First Cause is wholly removed from our apprehension is
not simply a disclaimer of faculty on our part: it is a charge of inability
against the First Cause too. The dictum about it is this: 'It is a Being
that may exist out of knowledge, but that is precluded from entering within
the sphere of knowledge.' We are told in one breath that this Being must be
in every sense 'perfect, complete, total--including in itself all power,
and transcending all law' (p. 38); and in another that this perfect and
omnipotent One is totally incapable of revealing any one of an infinite
store of attributes. Need we point out the contradictions which this
position involves? If you abide by it, you deny the Absolute and Infinite
in the very act of affirming it, for, in debarring the First Cause from
self-revelation, you impose a limit on its nature. And in the very act of
declaring the First Cause incognizable, you do not permit it to remain
unknown. For that only is unknown, of which you can neither affirm nor deny
any predicate; here you deny the power of self-disclosure to the
'Absolute,' of which therefore something is known;--viz., that nothing can
be known!"
[248] Loc. cit. p. 108.
[249] Loc. cit. p. 43.
[250] Loc. cit. p. 46.
[251] Mr. J. Martineau, in his "Essays," vol. i. p. 211, observes, "Mr.
Spencer's conditions of pious worship are hard to satisfy; there must be
between the Divine and human no communion of thought, relations of
conscience, or approach of affection." ... "But you cannot constitute a
religion out of mystery alone, any more than out of knowledge alone; nor
can you measure the relation of doctrines to humility and piety by the mere
amount of conscious darkness which they leave. All worship, being directed
to what is _above_ us and transcends our comprehension, stands in presence
of a mystery. But not all that stands before a mystery is worship."
[252] "Lay Sermons," p. 20.
[253] Loc. cit. p. 109.
[254] Loc. cit. p. 111.
[255] In this criticism on Mr. Herbert Spencer, the Author finds he has
been anticipated by Mr. James Martineau. (See "Essays," vol. i. p. 208.)
[256] Loc. cit. p. 29.
[257] The Author means by this, that it is _directly_ and _immediately_ the
act of God, the word "supernatural" being used in a sense convenient for
the purposes of this work, and not in its ordinary theological sense.
[258] The phrase "order of nature" is not here used in its theological
sense as distinguished from the "order of grace," but as a term, here
convenient, to denote actions not due to direct and immediate Divine
intervention.
[259] "A Free Examination of Darwin's Treatise," p. 29, reprinted from the
_Atlantic Monthly_ for July, August, and October, 1860.
[260] "Origin of Species," 5th edition, p. 571.
[261] "Animals and Plants under Domestication," vol. ii. p. 431.
[262] The Rev. Baden Powell says, "All sciences approach perfection as they
approach to a unity of first principles,--in all cases recurring to or
tending towards certain high elementary conceptions which are the
representatives of the unity of the great archetypal ideas according to
which the whole system is arranged. Inductive conceptions, very partially
and imperfectly realized and apprehended by human intellect, are the
exponents in our minds of these great principles in nature."
"All science is but the partial reflexion in the _reason of man_, of the
great all-pervading _reason of the universe_. And thus the _unity_ of
science is the reflexion of the _unity_ of nature, and of the _unity_ of
that supreme reason and intelligence which pervades and rules over nature,
and from whence all reason and all science is derived." (Unity of Worlds,
Essay i., § ii.; Unity of Sciences, pp. 79 and 81.) Also he quotes from
Oersted's "Soul in Nature" (pp. 12, 16, 18, 87, 92, and 377). "If the laws
of reason did not exist in nature, we should vainly attempt to force them
upon her: if the laws of nature did not exist in our reason, we should not
be able to comprehend them." ... "We find an agreement between our reason
and works which our reason did not produce." ... "All existence is a
dominion of reason." "The laws of nature are laws of reason, and altogether
form an endless unity of reason; ... one and the same throughout the
universe."
[263] In the same way Mr. Lewes, in criticising the Duke of Argyll's "Reign
of Law" (_Fortnightly Review_, July 1867, p. 100), asks whether we should
consider that man wise who spilt a gallon of wine in order to fill a
wineglass? But, because we should not do so, it by no means follows that we
can argue from such an action to the action of God in the visible universe.
For the man's object, in the case supposed, is simply to fill the
wine-glass, and the wine spilt is so much loss. With God it may be entirely
different in both respects. All these objections are fully met by the
principle thus laid down by St. Thomas Aquinas: "Quod si aliqua causa
particularis deficiat a suo effectu, hoc est propter aliquam causam
particularem impediantem quæ continetur sub ordine causæ universalis. Unde
effectus ordinem causæ universalis nullo modo potest exire." ... "Sicut
indigestio contingit præter ordinem virtutis nutritivæ ex aliquo
impedimento, puta ex grossitie cibi, quam necesse est reducere in aliam
causam, et sic usque ad causam primam universalem. Cum igitur Deus sit
prima causa universalis non unius generi tantum, sed universaliter totius
entis, impossibile est quod aliquid contingat præter ordinem divinæ
gubernationis; sed ex hoc ipso quod aliquid ex unâ parte videtur exire ab
ordine divinæ providentiæ, quo consideratur secundam aliquam particularem
causam, necesse est quod in eundem ordinem relabatur secundum aliam
causam."--_Sum. Theol_. p. i. q. 19, a. 6, and q. 103, a. 7.
[264] "Unity of Worlds," Essay ii., § ii., p. 260.
[265] See the exceedingly good passage on this subject by the Rev. Dr.
Newman, in his "Discourses for Mixed Congregations," 1850, p. 345.
[266] See Mr. G. H. Lewes's "Sea-Side Studies," for some excellent remarks,
beginning at p. 329, as to the small susceptibility of certain animals to
pain.
[267] "Philosophy of Creation," Essay iii., § iv., p. 480.
[268] It seems almost strange that modern English thought should so long
hold aloof from familiar communion with Christian writers of other ages and
countries. It is rarely indeed that acquaintance is shown with such
authors, though a bright example to the contrary was set by Sir William
Hamilton. Sir Charles Lyell (in his "Principles of Geology," 7th edition,
p. 35) speaks with approval of the early Italian geologists. Of Vallisneri
he says, "I return with pleasure to the geologists of Italy who preceded,
as has been already shown, the naturalists of other countries in their
investigations into the ancient history of the earth, and who still
maintained a decided pre-eminence. They refuted and ridiculed the
physico-theological systems of Burnet, Whiston, and Woodward; while
Vallisneri, in his comments on the Woodwardian theory, remarked how much
the interests of religion, as well as of those of sound philosophy, had
suffered by perpetually mixing up the sacred writings with questions of
physical science." Again, he quotes the Carmelite friar Generelli, who,
illustrating Moro before the Academy of Cremona in 1749, strongly opposed
those who would introduce the supernatural into the domain of nature. "I
hold in utter abomination, most learned Academicians! those systems which
are built with their foundations in the air, and cannot be propped up
without a miracle, and I undertake, with the assistance of Moro, to explain
to you how these marine monsters were transported into the mountains by
natural causes."
Sir Charles Lyell notices with exemplary impartiality the spirit of
intolerance on both sides. How in France, Buffon, on the one hand, was
influenced by the theological faculty of the Sorbonne to recant his theory
of the earth, and how Voltaire, on the other, allowed his prejudices to get
the better, if not of his judgment, certainly of his expression of it.
Thinking that fossil remains of shells, &c., were evidence in favour of
orthodox views, Voltaire, Sir Charles Lyell (Principles, p. 56) tells us,
"endeavoured to inculcate scepticism as to the real nature of such shells,
and to recall from contempt the exploded dogma of the sixteenth century,
that they were sports of nature. He also pretended that vegetable
impressions were not those of real plants." ... "He would sometimes, in
defiance of all consistency, shift his ground when addressing the vulgar;
and, admitting the true nature of the shells collected in the Alps and
other places, pretend that they were Eastern species, which had fallen from
the hats of pilgrims coming from Syria. The numerous essays written by him
on geological subjects were all calculated to strengthen prejudices, partly
because he was ignorant of the real state of the science, and partly from
his bad faith." As to the harmony between many early Church writers of
great authority and modern views as regards certain matters of geology, see
"Geology and Revelation," by the Rev. Gerald Molloy, D.D., London, 1870.
[269] "De Genesi ad Litt.," lib. v., cap. v., No. 14 in Ben. Edition, voi.
iii. p. 186.
[270] Lib. cit., cap. xxii., No. 44.
[271] Lib. cit., "De Trinitate," lib. iii., cap. viii, No. 14.
[272] Lib. cit., cap. ix., No. 16.
[273] St. Thomas, Summa, i., quest. 67, art. 4, ad 3.
[274] Primæ Partis, vol. ii., quest. 74, art. 2.
[275] Lib. cit., quest. 71, art. 1.
[276] Lib. cit., quest. 45, art. 8.
[277] _Vide_ In Genesim Comment, cap. i.
[278] Roger Bacon, Opus tertium, c. ix. p. 27, quoted in the _Rambler_ for
1859, vol. xii. p. 375.
[279] See _Nature_, June and July, 1870. Those who, like Professors Huxley
and Tyndall, do not accept his conclusions, none the less agree with him in
principle, though they limit the evolution of the organic world from the
inorganic to a very remote period of the world's history. (See Professor
Huxley's address to the British Association at Liverpool, 1870, p. 17.)
[280] "Lectures on Metaphysics and Logic," vol. i. Lecture ii., p. 40.
[281] In the same way that an undue cultivation of any one kind of
knowledge is prejudicial to philosophy. Mr. James Martineau well observes,
"Nothing is more common than to see maxims, which are unexceptionable as
the assumptions of particular sciences, coerced into the service of a
universal philosophy, and so turned into instruments of mischief and
distortion. That "we can know nothing but phenomena,"--that "causation is
simply constant priority,"--that "men are governed invariably by their
interests," are examples of rules allowable as dominant hypotheses in
physics or political economy, but exercising a desolating tyranny when
thrust on to the throne of universal empire. He who seizes upon these and
similar maxims, and carries them in triumph on his banner, may boast of his
escape from the uncertainties of metaphysics, but is himself all the while
the unconscious victim of their very vulgarest deception." ("Essays,"
Second Series, _A Plea for Philosophical Studies_, p. 421.)
[282] Lecky's "History of Rationalism," vol. i. p. 73.
[283] "Lectures on University Subjects," by J. H. Newman, D.D., p. 322.
[284] Loc. cit. p. 324.
[285] Thus Professor Tyndall, in the _Pall Mall Gazette_ of June 15, 1868,
speaking of physical science, observes, "The _logical feebleness_ of
science is not sufficiently borne in mind. It keeps down the weed of
superstition, not by logic, but by slowly rendering the mental soil unfit
for its cultivation."
[286] By this it is not, of course, meant to deny that the existence of God
can be demonstrated so as to demand the assent of the intellect taken, so
to speak, by itself.
[287] See some excellent remarks in the Rev. Dr. Newman's Parochial
Sermons--the new edition (1869), vol. i. p. 211.
[288] _American Journal of Science_, July 1860, p. 143, quoted in Dr. Asa
Gray's pamphlet, p. 47.
[289] See _The Academy_ for October 1869, No. 1, p. 13.
[290] Professor Huxley goes on to say that the mechanist may, in turn,
demand of the teleologist how the latter knows it was so intended. To this
it may be replied he knows it as a necessary truth of reason deduced from
his own primary intuitions, which intuitions cannot be questioned without
_absolute_ scepticism.
[291] The Professor doubtless means the _direct_ and _immediate_ result.
(See Trans. Zool. Soc. vol. v. p. 90.)
[292] "Natural Selection," p. 280.
[293] Dr. Asa Gray, _e.g._, has thus understood Mr. Darwin. The Doctor says
in his pamphlet, p. 38, "Mr. Darwin uses expressions which imply that the
natural forms which surround us, because they have a history or natural
sequence, could have been only generally, but not particularly designed,--a
view at once superficial and contradictory; whereas his true line should
be, that his hypothesis concerns the _order_ and not the _cause_, the _how_
and not the _why_ of the phenomena, and so leaves the question of design
just where it was before."
[294] "All science is but the partial reflexion in the _reason of man_, of
the great all-pervading _reason of the universe_. And the _unity_ of
science is the reflexion of the _unity_ of nature and of the _unity_ of
that supreme reason and intelligence which pervades and rules over nature,
and from whence all reason and all science is derived." (Rev. Baden Powell,
"Unity of the Sciences," Essay i. § ii. p. 81.)
[295] "The Reign of Law," p. 40.
[296] Though Mr. Darwin's epithets denoting design are metaphorical, his
admiration of the result is unequivocal, nay, enthusiastic!
[297] See "Habit and Intelligence," vol. i. p. 348.
[298] The term, as before said, not being used in its ordinary theological
sense, but to denote an immediate Divine action as distinguished from God's
action through the powers conferred on the physical universe.
[299] See "Natural Selection," pp. 332 to 360.
[300] Loc. cit., p. 349.
[301] See Professor Huxley's "Lessons in Elementary Physiology," p. 218.
[302] It may be objected, perhaps, that excessive delicacy of the ear might
have been produced by having to guard against the approach of enemies, some
savages being remarkable for their keenness of hearing at great distances.
But the perceptions of _intensity_ and _quality_ of sound are very
different. Some persons who have an extremely acute ear for delicate
sounds, and who are fond of music, have yet an incapacity for detecting
whether an instrument is slightly out of tune.
[303] Loc. cit., pp. 351, 352.
[304] Loc. cit., p. 368.
[305] Loc. cit., p. 350.
[306] Published by John Churchill.
[307] Natural Selection, p. 324.
[308] The italics are not Mr. Wallace's.
[309] "Unity of Worlds," Essay ii. § ii. p. 247.
[310] Ibid. Essay i. § ii. p. 76.
[311] Ibid. Essay iii. § iv. p. 466.
[312] A good exposition of how an inferior action has to yield to one
higher is given by Dr. Newman in his "Lectures on University Subjects," p.
372. "What is true in one science, is dictated to us indeed according to
that science, but not according to another science, or in another
department.
"What is certain in the military art, has force in the military art, but
not in statesmanship; and if statesmanship be a higher department of action
than war, and enjoins the contrary, it has no force on our reception and
obedience at all. And so what is true in medical science, might in all
cases be carried out, _were_ man a mere animal or brute without a soul; but
since he is a rational, responsible being, a thing may be ever so true in
medicine, yet may be unlawful in fact, in consequence of the _higher_ law
of morals and religion coming to some different conclusion."
[313] Quoted from the _Rambler_ of March 1860, p. 364: [Greek: "Hopou men
oun hapanta sunebê, hôsper kain ei heneka tou egineto, tauta men esôthê apo
tou automatou sustanta epitêdeiôs hosa de mê houtôs apôleto kai apollutai,
kathapeo Empedoklês legei ta bougenê kai androprôra.]"--ARIST. _Phys._ ii.
c. 8.
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