Saturday, 7 March 2015

PROFESSOR OWEN ON THE ORIGIN OF SPECIES.

Palæontology ; or, a Systematic Summary of Extinct Animals and their Geological Relations By Richard Owen, F.R.S., &c, &c. Edinburgh: Black.

   A SUMMARY of the present state of knowledge in regard to an important branch of natural science, coming from the pen of its greatest living authority, can require no fiat of contemporary criticism to secure the attention of the students of science, and that of the much larger number who desire, with the least possible trouble, to keep themselves informed as to its main results. The latter class are especially indebted to Professor Owen for having consented to condense and compress into a single volume his vast store of knowledge, and the fruits of the assiduous application of his powerful intellect, to widening the range of our acquaintance with the inhabitants of the earth during the past epochs of geological time. The student may, perhaps, regret that, for the attainment of that object, the author has found it necessary to compress important branches of his subject within such narrow limits, that not more than ninety pages are devoted to all the classes of invertebrate animals; but this merely amounts to the wish that he had written a complete treatise instead of a summary. It may perhaps, be surmised that our great comparative anatomist reserves for the termination of his scientific labours the completion of a new Animal Kingdom,? wherein the constantly increasing results of discovery and study in enlarging and completing the edifice constructed by his illustrious predecessor maybe finally reduced to order and shape by the living successor of George Cuvier.     

Be this as it may, the present volume will be read as well by the many who are content to accept with submission the dicta of the master as by the few who are not afraid to question his judgment upon particular points. The portions of the work that will most excite the interest of readers are naturally those in which the need of abridgment has been least felt by the writer and he has allowed himself to develops with some completeness the facts and reasonings that have given to our knowledge of the structure and habits of many extinct animals—known only by portions of their bony skeleton—a character of certainty scarcely inferior to that of our acquaintance with the species that are kept in zoological gardens. The parts of the volume devoted to the Reptiles and Mammalia contain many pages that cannot fail to interest deeply the most cursory reader who has learned enough of the glossary of comparative anatomy to understand the terms used to distinguish the several parts of the skeleton ; but those parts of the work which contain a mere summary of the author's views are unavoidably dry reading to those who have not already a pretty full acquaintance with the subject.

Quite irrespective of the solid matter that gives a permanent value the the present work there is an additional consideration that will attract many readers. The controversy excited by the appearance of Darwin's remarkable work on the "Origin of Species" has passed beyond the bounds of the study and lecture-room into the drawing-room and the public street. Those who have been persuaded by the argument and the skill with which Mr. Darwin presented his theory, or who have been simply led a way by the novelty of his views, and those who shrink from them with aversion, because of the dangerous consequences towards which they seem to point, have equally sought for confirmation of their own opinions in the judgments of the few who are really competent to form an independent judgment on the subject.

The few pages towards the close of his volume in which Professor Owen refers to the various hypotheses relating to the origin of species have, doubtless, been read with eagerness by very many who have not attempted to digest the entire work. Whether because a fuller discussion would have unduly swelled the dimensions of his book, or because the subject threatened to lead towards personal controversy—undesirable in such a work—the oracle is unusually reserved, and scarcely anything is said that might not have been inferred from its former utterances. Enough, indeed, there is to show the direction towards which the writer's opinions tend, but it seems as though he had imposed upon himself the rule which, as he says elsewhere, nature follows in her teachings —they are whispered rather than outspoken. It is plain that he does not believe that the last hypothesis, any more than its predecessors, has solved the mystery of the ultimate problem of zoology ; but it is equally evident that he does not regard as satisfactory the opinion that the first formation of each new species is due to a separate and intermittent exertion of the will of the Creator, and that he looks forward to the future discovery of a secondary law by which the appearance of new forms of animated nature has been regulated. 

Those who may have been disappointed in their desire for a fuller statement of the opinions of so eminent an authority on the chief scientific controversy of the day had not to wait very long for the satisfaction of their curiosity. In the Edinburgh Review of last month there is an article which certainly cannot be charged with any undue reticence, either in criticising the works of others or in expressing the views of the anonymous writer. We will not attempt to decide whether he has sat at the feet, or stood in the very shoes, of the author of Palæontology, but it is perfectly clear that the reviewer has done no more than develope and expand the ideas which are implicitly contained in the last few pages of the work, whose publication very shortly preceded that of the Review. He has used the same arguments and the same materials; and we may therefore not unfairly conclude that he represents the deliberate opinions of the eminent Professor, leaving those who are curious in such inquiries to investigate for themselves the question of identity. 

There is no denying that, with those who regulate their opinions by the judgment of others, the decided opposition of the foremost living comparative anatomist will go far to neutralise the advantage which the new theory has obtained by the adhesion of several scarcely less distinguished names. The small number of those who—not sufficiently conspicuous to have become parties in the controversy—are striving with due patience and caution to form an independent judgment upon the subject of this deeply interesting discussion, may probably differ in their estimate of the real importance of the attack to which the theory of natural selection is subjected by the Edinburgh reviewer. It seems beyond question that neither Mr. Darwin nor some of the other writers engaged have sufficiently taken account of that great reserve of undiscovered truth which biology, even more than other branches of science, has hitherto kept concealed from the student of nature. Forgetting how much still remains for future discovery and speculation, they have argued as if these were no option between acceptance of natural selection as the one preponderating, if not exclusive, agency by which new forms of organised life have appeared on our earth, and the utter denial of any secondary law of the creation of species. It is pretty certain that, if Professor Owen had not hitherto thought it unwise to give definite expression to the ideas which he has froth time to time hinted at, neither Mr. Darwin nor any other competent naturalist would have overlooked his opinions or failed to give them the consideration to which they are necessarily entitled. He has deliberately refrained from the enunciation of any hypothesis ; perhaps he has not allowed himself even to form any clear conception of the relation which the phenomena of vegetative repetition—of relation to, and progressive departure from, an archetype—of parthenogenesis—may bear to each other in that ultimate theory of the Origin of Species of which Palæontology gives foreboding, but which is more distinctly presaged by the Edinburgh reviewer. No one surely will blame the prudent reserve that has restrained Professor Owen—as it has restrained many of the greatest scientific inquirers—from advancing a single step upon the uncertain ground of speculation, and kept them rigidly confined to the firm footway of inductive reasoning; but neither can we agree with the reviewer who would proscribe every attempt to strike out a new path, and who denies that such attempts have contributed to the progress of science. The field to be occupied is so vast and the obstacles to progress so numerous that Science can find suitable service for all who enrol themselves under her banner. She admits recruits of the most opposite faculties and tempers—nay, more true it is, that she cannot well dispense with them. If Wellington had been once led away by the spirit of adventure, he never would have carried the British arms from Torres Vedras to the Bidassoa, nor achieved the day of Waterloo ; if Victor Emmanuel had not thrown himself amongst the Austrian bayonets at Palestro, he would probably not now rule over Florence, Parma, Modena, and Bolonga, and certainly not hold his present place in the esteem and the affections of his countrymen. Not to name other branches of science, we may fairly ask whether geology, or which palæontology is the chief handmaid and guide, would ever have attained to its present comparatively mature condition if its founders had rigidly abstained from every hypothesis that was not sustainable by complete inductive demonstration? Did the Wernerian and Huttonian theories contribute in no degree to our knowledge of the earth's past history ? Have not the speculations of Agassiz and Charpentier helped to lead us to a far more complete knowledge of its condition during the period immediately preceding the present order of things? The progress of science has indeed been cumbered by the accumulation of vast piles of worthless speculation—worthless, not because it went beyond the limits of demonstration, but because it did not start from the basis of truth and nature. The man whose genius or fortune enables him to discern a link in the mechanism of nature hitherto overlooked is almost certain to be dazzled by the light bf his own discovery, and to overestimate the extent and the efficacy of its operations. Such has been the case in each of the instances above cited—it is the tribute which even superior minds pay to the common infirmity of our nature—and in our opinion it has been the case with Mr. Darwin.

Natural selection will, we are persuaded, be henceforward recognised as a vera causa which has operated both in modifying those that have ceased to be fully adapted to the surrounding conditions of existence; but we are equally persuaded that, taken by itself, it is inadequate to explain the entire past history of vital phenomena as developed in our planet. If we endeavour to apply the hypothesis in its absolute form, and to trace the derivation of all organised beings from a single original, we are met, amongst a host of minor difficulties, by that most startling one—the utter disappearance of whole tribes and classes of animals and plants that must have once existed if the chain of organised life were in truth a continuous one, yet have left no relics in the contemporaneous formations. Defective as the geological record may be, every class and almost every order of existing aquatic animals is represented by fossils extracted from the Silurian strata. If the Palæozoic fishes descended from a common ancestor with their contemporary Crustaceans and Cephalopods, where are the remains of those classes and orders that must have intervened in the line of descent? The longer the genealogy, the greater the probability of finding some of the family records.

It may be supposed that some such difficulty as this induced Mr. Darwin to hesitate at carrying out his theory to its utmost length, and to lean to the supposition that the beginnings of organised existence may have been, not a single one, but four or five primitive types of animals, and an equal number of plants. The consequences of this modification of the theory have scarcely been sufficiently noticed either by hostile or by friendly critics. No competent zoologist has studied the organisation of the cuttle-fish without being struck by the analogies presented by the structure of that singular animal with each one of the great divisions of the animal kingdom. The tribe to which it belongs made its appearance comparatively late in the world's history. Let us suppose, in accordance with Mr; Darwin's theory, that this most highly organised of mollusks had been gradually improved by natural selection from a low primitive type. Whence are derived the analogies that connect this descendant of the original mollusk with the offspring of the first radiate, the first articulate, and the first vertebrate animal ?  Do they not give distinct intimation of the presence of another law of structure, another vera causa regulating the forms of the animated world, besides that natural selection whose agency Mr. Darwin has been the first clearly to bring to light? Is it not more philosophical to search patiently for the true nature of the cause that lies behind, recognised, though not seen, when we use the word "analogy", as applicable to the relations of all organised beings, than to disregard the obvious indications of its presence, and fill up the broad chasm of our ignorance by assumptions that may be admitted to be within the range of bare possibility, but which are certainly not sustained by the only available evidence ?

Many of those who may be disposed to agree more nearly with the opinions of the Edinburgh reviewer than with those of Mr. Darwin, will nevertheless regret some passages wherein the former writer seems to have been led, in the ardour of controversy, to forget somewhat of the mutual respect which all earnest seekers for truth owe each other. Independently of the amply sufficient evidence given by his own assertion of the fact, there appears nothing improbable in Mr. Darwin's statement that his ideas as to the origin of species were first suggested by reflection on the relation between the present and the past inhabitants of South America. The prolonged existence of certain peculiar types of structure amongst animals specifically, and even generically distinct, inhabiting a geographically isolated region, is a fact which, so far as it goes, points towards the supposition that such animals might have been derived from a common ancestor. In another portion of the same review the writer attacks in vehement terms another distinguished contemporary, on account of a lecture delivered at the Royal Institution, for the purpose of explaining and illustrating Mr. Darwin's views. Professor Huxley has not always treated received opinions and established reputations with much tenderness ; but we are bound to say that the lecture in question did not appear to many of the hearers to deserve the censures with which it has been visited by the reviewer, who, if he had been present, would scarcely have regarded the parallel drawn between the series of varieties produced by selection, and the supposed relation existing between four existing genera of ungulate quadrupeds, as one adopted and defended by the lecturer, instead of being simply an illustration of the theory he was seeking to explain. The reviewer suggests a parallel between the varieties of the horse and those of the pigeon. It may be more applicable and more true than that given at the Royal Institution, but it would be no illustration of the Darwinian theory. That theory rests on the assumption, that if a sufficient lapse of time and other favourable conditions be allowed, the progeny of a common ancestor may be modified through natural selection until they differ as widely us the horse, the tapir, the rhinoceros, and the hyrax. It is quite true that the tapir is more nearly allied to the extinct Lophiodon than to the Palæotherium; but if we are not greatly mistaken, the freshwater beds of Languedoc that have yielded the remains of Lophioden are of miocene age, while the more ancient Palæotherium comes from the upper eocene of France and England. It is at least possible that Mr. Darwin may regard the newer quadruped as the modified descendant of the older one, and the existing tapirs as modern representatives of the same branch of the family.

With the charge of heterodoxy, which is rather freely urged against the reviewer's opponents, we prefer not to meddle. The writer must know that similar charges have been launched in succession against all those whose labours have most contributed to establish geology on its present basis. Sedgwick, Buckland, Lyell, and Owen have each in turn been denounced as subverters of established religious truth. Men of science at least should be sparing in the use of such arms. It is their part to maintain the doctrine that physical truth, attained by the legitimate use of observation and reasoning, cannot possibly contradict the teachings of true religion. Those who believe that the testimony of nature, as pronounced in the geologic record, is opposed to the new theory, may be content to try the issue upon that ground alone. To appeal to an external authority seems to imply a doubt of the soundness of their own case.

 Empire 16 July 1860,

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