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de verd, de rongc, do violet, do eouleur d'or et d'azur; ct cola precise'ment dana les mCmcs partics ou les plumages dc ces memos oiseaux sont diversific's il'une manierc si bizarre."*
Dcmaillct, it must bo admitted, enters move fully into the details of the operation of "natural selection," in changing the fish into the bird; and it is, perhaps, from this very "naivete" in the exposition of his theory, that its weakness has been made 60 obvious to later zoologists and comparative anatomists. Mr. Darwin rarely shows a fair front to these searching tests; the facts of the manner of transmutation, as they might have presented themselves to his fancy, are not stated with the "abandon" of the old French Philosopher. Vague and general as is the illustration based upon Hearne's remark, it is made still more vague in a later reprint of the volume " On the Origin of Specicc." It now reads, "In North America, the black bear was seen by Hearne swimming for hours with widely opened mouth, thus catching, almost like a whale, insects in the water." (Ed. 18G0, p. 184.)
"Individuals, it is said, of every species, in a state of nature, annually perish," and "the survivors will be, for the most part, those of the strongest constitutions and the best adapted to provide for themselves and offspring, under the circumstances in which they exist." Now, let us test the applicability of this postulate to the gradual mutation of a specific form by some instance in Natural History eminently favorable for the assumed results. In many species, nature has superadded to general health and strength, particular weapons and combative instincts, which, as, e. g., in the deer-tribe, insure to the strongest, to the longest-winded, the largest-antlered, and the sharpest-snagged stags, the choice of the hinds and the chief share in the propagation of the next generation. In such peculiarly gifted species we have the most favorable conditions for testing one of the conclusions drawn by Messrs. Darwin and Wallace from this universally recognized "struggle for the preservation of life and kind." If the offspring, inheriting the advantages of their parents, did in their turn, however slightly and gradually, increase those advantages, and give birth to a still more favored progeny, with repetition of the result to the degree required by " nat
* "Telliamed, ou Entretiens d'un Philosopho Indien avee an Missionniro Kranoois, sur la Diminution do la Mcr," etc.. Svo, Amsterdam, 1708. 'An edition in two volumes of this original and suggestivo work, was printed, witli the life of tho author (Demnillet), at the Hague, in 1755. The passage quoted will be found at p. 166, torn. ii. of this edition.)
ural selection," —then, according to the rate of modification experimentally proved in pigeons, we ought to find evidence of progressive increase in the combative qualities of antlers in those deer that for centuries have been under observation in our parks, and still more so in those that have fought and bred from the earliest historical times in the mountain wilds of Scotland. Tho element of "natural selection," above illustrated, either is, or is not, a law of nature. If it be one, the results should be forthcoming; more especially in those exceptional cases in which nature herself has superadded structures, as it were, expressly to illustrate the consequences of such "general struggle for the life of the individual and the continuance of the race." * The antlers of deer are expressly given to the male, and permitted to him, in fighting trim, only at the combative sexual season; they fall and ore renewed annually; they belong, moreover, to the most plastic and variable parts or appendages of the quadruped. Is it, then, a fact that the fallow-deer propagated under these influences in Windsor Forest, since the reign of William Rufus, now manifest in the superior condition of the antlers, as weapons, that amount and kind of change which the successions of generations under the influence of "natural selection" ought to have produced? Do the crowned antlers of the red deer of the nineteenth century surpass those of the turbaries and submerged forest-lands which date back long before the beginning of our English history? Does the variability of the artificially bred pigeon, or of the cultivated cabbage outweigh, in a philosophical consideration of the origin of species, those obstinate evidences of persistence of specific types and of inherent limitation of change of character, however closely the seat of such characters may be connected with the "best chance of taking care of self and of begetting offspring?" If certain bounds to the variability of specific characters be a law in nature, we then can see why the successive progeny of the best antlereu deer, proved to be best by wager of battle, should never have exceeded the specific limit assigned to such best possible antlers under that law of limitation. If unlimited variability by "natural selection" be a law, we ought to see some degree of its operation in the peculiarly favorable test-instance just quoted.
That the variability of an organism to a certain extent is a constant and certain condition of life we admit, otherwise there
* " Individual males have had, in successive generations, some slight ndvantngo over other males ia their weapons, and have transmitted these advantages to their male offspring."—Darwin, p. 89
would be no distinguishable individuals of a species. The forester, by the operation of this law of variability, is able to distinguish his individual oaks, the shepherd his particular sheep, the teacher his several scholars. This true and proved law of variability is, in fact, the essential condition of individuality itself. We have searched in vain, from Demaillet to Darwin, for the evidence or the proof, that it is only necessary for one individual to vary, be it ever so little, in order to the conclusion that the variability is progressive and unlimited, so as, in the course of generations, to change the species, the genus, the order, or the class. We have no objection to this result of "natural selection" in the abstract; but we desire to have reason for our faith. What we object to is, that science should be compromised through the assumption of its true character by mere hypotheses, the logical consequences of which are of such deep importance.
The powers, aspirations, and missions of man are such as to raise the study of his origin and nature, inevitably and by the very necessity of the case, from the mere physiological to the psychological stage of scientific operations. Every step in the progress of this study has tended to obliterate the technical barriers by which logicians have sought to separate the inquiries relating to the several carts of man's nature. The considerations involved in tho attempt to disclose the origin of the worm are inadequate to the requirements of the higher problem of the origin of man; and it may be that the conditions of that problem are beyond our present powers of acquiring certain knowledge.
To him, indeed, who may deem himself devoid of soul and as the 'brute that perisheth, any speculation, pointing, with the smallest feasibility, to an intelligible notion of the way of coming in of a lower organized species, may be sufficient, and he need concern himself no further about his own relations to a Creator. But when the members of the Royal Institution of Great Britain are taught by their evening lecturer that such a limited or inadequate view and treat„ ment of the great problem exemplifies that application of science to which England owes her greatness, we take leave to remind the managers that it more truly parallels the abuse of science to which a neighboring nation, some seventy years since, owed its temporary degradation. By their fruits may tho promoters of true and false philosophy be known. We gazed with amazement at the audacity of the dispenser of the hour's intellectual amusement, who, availing himself of the technical ignorance of the majority of his auditors, sought to blind them as
to the frail foundations of "natural selection" by such illustrations as the subjoined:
Umax Rhinoceros Tapir Horse
i i r i
Tumbler Bunt Pouter Fantail
I I I I
The above diagrams were set before an intelligent audience by a professor, in whom they naturally repose confidence as to facts specially belonging to his science, as parallel instances of departure from type: the one illustrating the extent and directions in which varieties diverge from a type form, in long course of time, by "natural selection j" the other showing the correlative examples of such divergence, in a short course of time, through human selection. He told them that, in the latter series, the skeleton varied in regard to tho number of vertebra; but did not remark that it was in the variable region of the tail, on which no ornithologist ever depended for a specific character, neither did he state that the i llegcd difference in the number of dorsal vertebnc * was one that is merely simulated by a greater or less extent of the process of anchylosis over a region of the spinal column in which every vertebra; was originally distinct. With regard to the parallel diagram, no allusion was made to such differences in the relative position of the cranial bones as tho following, viz.: that in the palieotherium, as in the tapir, the maxillary bones intervene between and separate the nasal bones from the intermaxillary bones; whilst in the horse, as in the hyrax, the nasal and intermaxillary bones are united as far as their extremities; that, consequently, the external nostril is bounded by four bones in the horse, but by six in its implied progenitor; tha* there is as marked a difference in the conformation of the orbit, which is encircled by the union of the malar with the frontal bone in the horse, but is left widely open or incomplete, by the want of such union in the same two cranial bones of the pahcothere. The advocate of the "natural selection" view exaggerated resemblances and glossed over discrepancies of structure. The resemblance of the Pakeothere to its four hypothetical descendants, in respect of their more generalized or more specialized structures, was flippantly affirmed to be as that of a father to his four sons! t
* Dnrwin, p. 22.
t Professor Huxley's Lectnre "On Species nnd Races aiid their Origin," Friday, February 10th, Nothing was said to give his hearers a notion of the important difference between the horse and palceothere in the structure and implantation of the whole dental Bystem. Yet the horse resembles the elephant in having a long mass of complexly intcrblended dental substances deeply implanted in a large simple socket; whilst the pala?othere differs from both, in having a short mass or crown of differently disposed dental substances implanted by several long fangs in a correspondingly complex socket. To the competent anatomist a score of such anatomical differences would be present to the memory in contrasting the two alleged parallel series of differences from selection natural and human; to which differences in the palo?ontological series nothing comparable inessential value has been pointed out in the varieties of Columba livia. The competent palaeontologist, moreover, would detect the superficial character of the knowledge that would interpose the tapir in any series leading from paltrotherium: he would point to the eocene lophiodon as the true ancestor of the tapir on the derivative hypothesis.
Neither zoology nor physiology as yet, however, possesses a single fact to support the idea that six incisor and two canine teeth, as in the palreothere, could be blended or changed, by progressive transmutation, into the pair of large scalpriform teeth that projects from the fore part of the lower jaw m the hyrax or scriptural coney. The genuine cultivator of science and true representative of the minds on which the glory and freatness of nations depend, would feel ound to illustrate any series of observed varieties of a species by a true parallel. The hoofed mammals which afford this parallel with the diverging series of pigeons, ore the following:—
morphologically but physiologically alike; not merely are the differences of form and structure similar and equivalent, but the
Eowers of procreation are the same. "The ybrids or mongrels from between all the domestic breeds of pigeons are perfectly fertile ; " * so, likewise, are the hybrids or mongrels from between all the domestic breeds of the horse. Now, as this is not the case with the hybrid between any variety of the horse and of the ass, it may be inferred that the physiological distinction would be, at least, as great, or more insuperable, between the horse and the tapir, or the rhinoceros, or the palceotherium. The infertility, or very rare fertility, of the solipedous mule, even when paired with a true horse or ass, and the absolute infertility of such hybrids inter se, are facts so notorious, that the professorial advocate cf ''natural selection" was compelled to admit that his alleged parallel broke down at the physiological test,— the most important element of the comparison.
It is assumed by Mr. Darwin that variations, useful in some way to each being, occur naturally in the course of thousands of generations (p. 80), that such variations are reproduced in the offspring, and, if in harmony with external circumstances, may be heightened in still further modified descendants of the species. The transmission and exaggeration of a variety, step by step, in the generative series, essential to the theory of "natural selection," implies the fertility of the individuals constituting the several steps of the series of transmutation. But numerous instances, familiar to every zoologist, suggest an objection which seems fatal to the theory, since they show extreme peculiarities of structure and instinct in individuals that cannot transmit them, because they are doomed to perpetual sterility.
The most numerous and important members of the hive, which collect the pollen on their peculiarly expanded thighs, and the honey in their peculiarly valvular crop or "honey-bag," and which, in the construction of cells of a shape adapted to contain the greatest possible quantity of honey with least possible consumption of wax, have practically solved a recondite mathematical problem, are the neuters, or females with abortive sexual organs,—'' non-breeding females" of our great physiologist Hunter. From the hypothetical protoplastic progenitor of all animal species, what an enormous scries of i " slight modifications of structure and in[ stinct" must have rolled, snow-ball like, I along the articulate line of departure, to have I accumulated, according to "natural selec! tion," in the Apis mellifica, which in the * Darwin, p. 26.
days of Moses exercised as now their structures and instincts in the " land flowing with milk and honey!"
So also in the family of ants, the neuters or sterile females form, in certain species, two, or even three castes,—soldiers, workers, nurses. In Cryptocerus the workers of one caste " carry a wonderful sort of shield on their heads;" in the Mexican genus, Myrmecocystus, the workers of one caste are ted by the workers of another caste, and have an enormously expanded abdomen where a sort of honey is secreted and stored, which, like domestic cattle they supply to the rest of the community. Mr. Darwin, with one of his usual happy illustrations, compares the workers of the " driver ant" (Anomma), to a " set of workmen building a house, of whom many were five feet four inches high, and many sixteen feet high; but we must suppose that the larger workmen had heads four instead of three times as big as those of the smaller men, and jaws nearly five times as big;" in short, the most grotesque and extravagant scene in a pantomime is realized in the industrial community of a West African ant.
Yet all these instances of exaggerated peculiarities of structure and instinct are manifested in individuals which never could have transmitted them.
No zoologist, perhaps, is better acquainted with these fatal exceptions to his principle of the organization of species by hereditary transmission of variation characters, than Mr. Darwin. He could not, with any pretension to free and candid discussion, pass over the chief instances which have checked the natural disposition of all zoologists to obtain inductively an intelligible idea of the most mysterious phenomena of their science. But the barrier at which Cuvier hesitated, Mr. Darwin rushes through, and thus he disposes of the difficulty:—
"We have even slight differences in the horns of different breeds of cuttle in relation to nn artificially imperfect state of the malo sex; for oxen of certain breeds have longer horns than in other breeds, in comparison with the horns of the bulls or cows of the same breeds. Hence I can see no real difficulty in any character having become correlated with the sterile condition of certain members of insect communities: the difficulty lies in understanding how such correlated modifications of structure could have been slowly accumulated by natural selection.
"1 have such faith in the powers of selection, that I do not doubt that a breed of cattle, always yielding oxen with extraordinarily long horns, could bo slowly formed by carefully watching which individual bulls and cows, when matched, produce oxen with the longest horns; and yet no one ox could ever have propagated its kind. Thus I believe it has been with social insects : a
slight modification of structure, or instinct, correlated with the sterile condition of certain members of the community, has been advantageous to the community: consequently the fertile males and females of the same community flourished, and transmitted to their fertile offspring a tendency to produce sterile members having the same modification."—P. 238.
It is a notorious and constant fact, that the castrate bovine has longer horns than either the perfect male or female. The progressively elongating result in the case of the oxen, about which our theorist does not doubt, has not been proved experimentally. It is capable of proof or disproof. In scientific questions of far less import than the origin of animal species, involving our own, small value, if any, is attached to supposititious cases.
It is, doubtless, by no means necessary that we should sow a seed of the very cauliflower we eat in order to get more cauliflowers; seed of other individuals of the same stock will suffice. So the bee-keeper feels satisfied that the progeny of the impregnated young queen will exercise all the wonderful instincts which result in the production of wax and honey, as effectively as the virgin-sisters of the queen-mother, who were destroyed in the preceding winter. And our readers may well wonder what all this has to do with the explanation of the acquisition of the adaptive structures and instincts of neuter bees, by homoeopathic doses of Lamarckian transmutation, accumulating through a long series of hereditary transmissions? We cannot reply; we can only quote, with no less amazement, our author:—
"This difficulty, though appearing insuperable, is lessened, or, as I believe, disappears, when it is remembered that selection may be applied to the family, as well as to the individual, and may thus gain the desired end. Thus, a well flavored vegetable is cooked, and the individual is destroyed; but the horticulturist sows seed of the samo stock, and confidently expects to get nearly the same variety; breeders of cattle wish the flesh and fat to be well marbled together; the animal has been slaughtered, but the breeder pocs with confidence to the same family."—P. 237.
Now every step in the production of the breed or family of cattle may have been observed and recorded j and many of the incidents of the transmutative journey of the edible variety of cabbage from the wild stock may be similarly known; but this is just the knowledge that we desiderate in regard to the creation of the honey-bee by the way of I' natural selection j" and, instead of satisfying our craving with the mature fruit of inductive research, Mr. Darwin offers us the intellectual husks above quoted, endorsed by his firm belief in their nutritive sufficiency!
To more intelligible propositions in support of his hypothesis, we marginally noted, as we perused them, the difficulties or exceptions which rose in our mind. We have still room for a fiw of these illustrations of the groundwork of "natural selection."
"From looking nt species as only strongly marked and well-defined varieties, I was led to amicipate that tho species of the- larger genera in each country would oftener present varieties, tliau the species of tho smaller genera. To test I the truth of this anticipation I have arranged ! tho plants of twelve countries, and tho coleopterous insects of two districts, into two nearly equal masses, the species of tho larger genora on one side, and thoso of tho smaller genera on tho other 6ide, and it has invariably proved to bo tho caso that a larger proportion of tho species on tho side of the larger genera present varieties, than on the sido of tho smaller genera."—P. 55.
The elephant is, however, a small genus, indeed, one of the smallest in tho sense of the number of species composing it, which arc indeed but two, the Elephas Indicus and Elephas Africanus of Cuvier. But the range of variety in both African and Indian kinds is by no means inconsiderable. Livingstone adds instances in the elephants of the Zambesi, and the terms "Dauntclah," "Mooknah," etc., applied by the Indian and Singhalese entrappers of tho wild proboscidians to tho different varieties that are captured, still more exemplify this tendency to vary in individuals of a "small genus." Another exception to Mr. Darwin's rule as strongly and quickly suggests itself in the genus Pithecus. Naturalists seem unwilling to admit more species than the Bornean Pongo (Pithcm TVu)-mbii, scu Satyrus of Wurmb), mid the smaller orang (P. morio) since established by Owen. But the varieties in regard to the cranial crests, to color, to relative length of arms, appears by a memoir from the pen of the latter naturalist,* to be both numerous and well marked. On tho other hand, the species of tho antelope genus have not hitherto presented any notable varieties to the observation of naturalists; and yet the genus, in respect to the number of these species, is one of the largest in the mammalian class. There may be, of course, a difference in different classes of organisms in this respect. Plants and invertebrates may better exemplify Mr. Darwin's proposition than fishes, reptiles, or quadrupeds. But an hypothesis applied to all living things can only
* "Characters of the skull of the male Pilhecvt morio, with remarks on tho varieties cf Pilhecvt Satyrus," by Professor Owen. Zoological Transactions, vol. iv. p. 163. 1858.
be sustained by laws and rules of a like generality of application.
Mr. Darwin's argument for a common origin of all the varieties of dovecot pigeon, leads him to affirm, " all recent experience shows that it is most difficult to get any wild animal to breed freely under domestication." (P. 24.) But the recent experience at the Zoological Gardens of London tells a different story. Three young individuals, two males and one female, of those most strange exotic quadrupeds, the giraffe, were transported from their African wilderness to tho menagerie in Regent's Park in 1836.' No sooner had they attained the proper age in 1838 than they bred; and there has been no other interval in the repetition of tho act than that which the phenomena of a fifteen months' gestation and seven months' suckling necessarily interpose. "Nine fawns have been produced without any casualty."* A pair of the largest and wildest of antelopes (the Eland, A. Ocas) is transported from the boundless sunny plains of South Africa to the confinement of a park in cloudy and rainy Lancashire; they breed freely there, and become the parents of elands now widely distributed over Great Britain, and promising in another century to be as common in our parks as fallow deer.f What conditions might seem more adverse to health and procrcative power than such as are exemplified by the contrast cf tho den and the pond appropriated to the hippopotamus in tho Jardin des Plantcs, with that noble river where these most uncouth of African wild beasts disported themselves prior to their capture? Before two years elapse after the arrival of tho young male and female, they produce a fine offspring.
Such are the signs of defective information which contribute, almost at each chapter, to check our confidence in the teachings and advocacy of tho hypothesis of "Natural Selection." But, as we have before been led to remark, most of Mr. Darwin's statements elude, by their vagueness and incompleteness, the test of natural history facts.! Thus he says:—
"I think it highly probable that our domestic dogs have "descended from several wild species." It may bo so; but what arc the species here referred to? Are they known, or named, or can they be defined? If so, why are they not indicated, so that the> naturalist might have some means of judging of the degree of probability, or value of the surmise, and of its bearing on the hypothesis?
"Isolation, also," says Mr. Darwin, "is an important element in the process of natu
* Kdinb. Review, January, 1800, p. 179.