Russel Wallace : Alfred Russell Wallace (sic)
But our expectations have altogether led us astray. The volume is neither more nor less than a reprint of the various papers read before scientific societies, lectures, addresses, and magazine articles contributed by Dr. Cope during the last eighteen years. These numerous essays are extremely varied in character, and usually contain some new facts, original suggestions, and ingenious theories. As individual essays, many of them are of high excellence, and are well worthy of Mr. Cope's great reputation. What we think the reading public will justly complain of is, that no labor whatever has been bestowed upon them in order to fit them for consecutive perusal. Being composed at different times and for different audiences, they are full of repetitions--whole paragraphs, and sometimes whole pages, being printed twice over, as at pp. 10 and 176, and again at 50 and 177; while in another place we find that one-third of a chapter (five pages out of fifteen) is self-quotation. Again, the reader is utterly confused by finding a section of eight pages on Metaphysical Evolution, beginning on p. 148 in the division on "General Evolution;" another section of five pages on "Metaphysics of Evolution," beginning at p. 229, while the last division of the work consists of sixty more pages on "Metaphysical Evolution." Other repetitions, both of argument and illustration, are frequent. Chapter VI is almost the same as parts of Chapter IV, while Chapter III consists of a reporter's abstract, in the third person, of "Remarks" at a meeting of the Academy of Natural Sciences, and contains nothing which is not more fully treated in other chapters. Chapter X, on the other hand, is a verbatim report of an address, with all the little personal references and individualities of speech before an audience, unaltered. Even while misstatements as to fact or theory are made in the earlier papers, they are carefully preserved in the text, and merely corrected in foot-notes.
The manner in which the illustrations serve to give the minimum of information to the general reader is equally annoying. In the chapter on the Relation of Man to the Tertiary Mammalia there are some score of woodcuts of feet, bones, teeth and crania of mammals, but hardly one of them is directly referred to in the text, and no one but an experienced anatomist can discover the points they may be intended to illustrate. The same deficiency is found in Chapters XIV and XV, and though the former chapter is entitled "The Origin of the Specialized Teeth of the Carnivora" there is no reference to some of the most curious features of the tertiary mammals which are figured, such as the enormous elongation of the canine teeth and the downward enlargement of the lower jaw serving to protect them from injury.
It is this collection of incongruous materials, placed before the public without the alteration of a line or the erasure of a superfluous paragraph, which is, nevertheless, put forth as a fitting supplement to Darwin's "Origin of Species," of which work Mr. Cope does not seem to have a very high opinion. We are told, for example, that "the evidence in favor of evolution is abundant, and is cited in fragments by various contemporary writers, foremost among whom both in time and abundance of writings, comes Charles Darwin"; and a little further on we are assured that, "his theory of natural selection is to the plainest understanding incomplete as an explanation of the 'origin' of species." And again: "If, then, some of the people find Mr. Darwin's argument incomplete, or in some points weak, it may be answered, so do the student classes, who, nevertheless, believe it. This is largely because Darwin's facts and thoughts repeat a vast multiplicity of experiences of every student, which are of as much significance as those cited by him, and which only required a courageous officer to marshal them into line, a mighty host conquering and to conquer." These passages occur in the first three pages of the book, and serve as the keynote of the argument. Further on we find our author's position thus stated:
"Wallace and Darwin have propounded as the cause of modification in descent their law of natural selection. This law has been epitomized by Spencer as the 'survival of the fittest.' This neat expression no doubt covers the case, but it leaves the origin of the fittest entirely untouched. Darwin assumes a 'tendency to variation' in nature, and it is plainly necessary to do this, in order that materials for the exercise of a selection should exist. Darwin and Wallace's law is, then, only restrictive, directive, conservative, or destructive of something already created. I propose, then, to seek for the originative laws by which these subjects are furnished--in other words, for the cause of the origin of the fittest."
Here we have it very clearly laid down that there was nothing original in Darwin, that he was only one of a crowd, that his work was weak and imperfect, and that we are to look for Mr. Cope to supply its deficiencies and to crown the edifice. This is evidently supposed to be effected in the present volume, for though we are told in the preface that "the results could be better and more briefly presented in a systematic form, but the author reserves this for a future occasion," he clearly implies that it is all here if we will but take the trouble to disunite it from the mass of literary, scientific and metaphysical débris under which it is buried. We will, therefore, endeavor briefly to indicate what are the main points of Mr. Cope's new philosophy of evolution, and how far it goes beyond the teachings of Darwin himself.
The great points which Mr. Cope lays stress upon as supplementing Darwin's imperfect work are, (1) the existence of a special developmental force which he terms "bathmism" or "growth-force," in order to account for the prevalence of non-adaptive characters in animals--that is, of characters which are of no use to them; (2) the location of the action of this force by effort and use, or by the influence of the environment; and (3) the mechanical causes which have produced the different forms of teeth and feet in the mammalia.
(1.) That there is a "growth-force" in the organic world can hardly be termed a new discovery. Darwin and Herbert Spencer both recognize it and have endeavored to determine some of the laws of its action; but Mr. Cope claims to have discovered what he calls the law of acceleration and retardation, founded on the following fundamental principle--"every change by complication of structure is by addition; every simplification is by subtraction"; and then it is elaborately shown that the "additions" are caused by "acceleration of growth" in certain parts, and the "subtractions" by "retardation of growth," and these terms are thereafter used to explain every difficulty and to account for all structures and organs which it is assumed could not be produced by simple variations accumulated and fixed by natural selection.
It may of course be objected that the difficulty is only removed a step by suggesting a "growth-force" to explain variation, the fundamental cause of the growth-force remaining equally unknown; but waiving this, let us see what is the evidence for the existence of useless characters to the extent claimed, namely that--"perhaps half of all the peculiarities of the parts of animals (and probably of plants) are of no use to their possessors." We look in vain for any evidence except that we do not yet perceive the use of all structures. "It is easier to ask than to answer what advantages the mammalian skeleton possesses over the reptilian that it should have superseded it. What end was served by aborting the coracoid bone, which in reptiles supports the shoulder-joint from behind answering to the ischium of the pelvis? I do not know how to answer this question." Then, after describing the differences in the base of the skull in reptiles and batrachians, it is remarked--"Who can assign any advantage of the one type above the other which can be looked upon as in any way related to the external needs of the animals of these classes"? And of the varied forms of the nautilus and ammonite types of Mollusca we are told "The direct uses of these various forms of septum and coil are simply inexplicable, and that one of them was any 'fitter' to 'survive' than another, by virtue of its usefulness, is for me more than doubtful."
Arguments of this kind are surely extraordinary when we consider how very recently it has been discovered that many structures now equally useless once had their use. Everywhere in living animals, and even in man, are found bones, or bony processes, muscles, blood-vessels, appendages of the intestines and of various other organs, which seem perfectly useless to their possessors, but which, as comparative anatomy shows, are functional in some other animals, and must, therefore, have been usefully developed in some common ancestral form. In other cases the same part or organ has been modified in two or more distinct ways so as to subserve a different purpose from that which it had originally. With these examples before us, and the knowledge that they are being added to almost every year by further research, how rash it is to adduce our inability to see any use in a particular structure as a proof that it originated independently of use; especially when we remember that all the cases adduced by Mr. Cope date back in their origin to early geologic time; that the records of contemporary life are exceedingly fragmentary; that we know only the bony skeleton of a few of the more abundant species of each epoch, and that we are totally ignorant of the conditions under which they lived and the countless peculiarities of organization and habits with which their bony structure may have been correlated. The very possibility of any important divergences of structure having originated altogether apart from utility is almost inconceivable; for, admitting that certain initial forms may have been primarily due to unknown laws of growth, they must from their very beginning have been subject to the law of natural selection, and thus have been inevitably molded by slow gradations into harmonious and useful structures. That there are laws determining growth and to some extent determining organic forms we readily admit. What we deny is that these laws can have ever produced definite structures except under the controlling power of selection. They may have aided in supplying the variations which have enabled new groups to come into existence, but can never have produced important and persistent modifications of structure which were yet altogether useless.
(2.) The next proposition, that the growth-force is located by effort and use is the fundamental principle of Lamarck, and the effects of use have been fully recognized by Darwin. But Mr. Cope strangely overlooked the fact that whatever is initiated by these principles is necessarily subject from the very beginning to the accumulating and preserving power of natural selection. For animals strive after something that is needful, effort implying a want, while they make use of parts or organs which are more or less essential to their well-being. If, then, the effort, by directing the flow of blood or of nervous energy to a particular part, strengthens or enlarges that part, the result will be useful, and, therefore, those individuals will survive in whom the improvement is most manifest. It is conceivable, however, that the effort may be directed to something hurtful--as to the obtaining a poisonous or unwholesome plant for food, in which case natural selection will just as surely weed out and destroy all those individuals in which the abnormal desire leads to the injurious effort. The only cases in which natural selection would be excluded would be those in which the effort and use led to the growth of a part or structure which was absolutely indifferent, and yet of such small size and little importance that the tissues used in building it up were not required anywhere else. It is quite possible, and even probable, that some dermal structures, such as ornamental plumes or appendages, may have thus originated, but it is not credible that important modifications of the skeleton, or of the vascular or digestive system, can be due to such causes, still less that they should have persisted, through countless ages, without ever having acquired either a useful or a hurtful character.
(3.) Mr. Cope makes the further mistake of arguing that if a structure can be shown to be useful in one species or group, the use of the corresponding part in a similar manner in another species would tend to produce a similar structure. He adduces the similar hooked and toothed bills of the falcons and the butcher-birds as showing that the use of the bill in seizing and tearing flesh was the cause of the development of the tooth and hook. But a little consideration will show that there can be no such causal relation; for if the ancestors of the butcher-birds had bills like thrushes, and then took to eating young birds instead of worms, the greater exercise of the bill and head may conceivably have strengthened and thickened those parts, but could have had no tendency to have produced a tooth on the upper mandible. Neither could a change of food in mammals lead, by direct causation, to the various changes in the form and structure of the teeth, except, perhaps, by aborting some which were rarely or never used. If, however, we admit variations, from whatever causes, in the size, form and structure of teeth, then natural selection would inevitably seize upon all favorable variations to adapt them in each case to the kind of food which the various species were obliged to live on.
The most suggestive and interesting of the hypothetical explanations of important changes of structure made by our author is that which regards the modifications of the feet of the hoofed mammals. There are two great divisions of these, the odd and the even toed. In the former there are usually three toes, or the two lateral toes have disappeared and the middle toe alone remains, as in the hoof of the horse and ass. In the latter there is apparently no middle toe but two equal toes forming the cloven hoofs of our deer, sheep and cattle. The suggestion is, that these latter were developed through a long-continued habit of walking in mud or soft ground "which has a tendency to spread the toes equally on each side of the middle line, and this would encourage the equal development of the digits as in the cloven-footed types." But in progression on hard ground "the middle toe will receive the greatest amount of shock from contact with the earth, and there is every reason to believe that shocks, if not excessive, encourage growth in the direction of the force applied. Certain it is that the length of the bones in the feet of the ungulate orders have a direct relation to the dryness of the ground they inhabit and the possibility of speed which their habitat permits them, or necessarily imposes on them."
In this there is probably some truth, but it is all included in the effects of use so powerfully insisted on and so well illustrated by Spencer and Darwin. And it is evident that whatever cumulative effect was ultimately produced was due to the influence of natural selection preserving those modifications only which were on the whole useful. This is proved by the consideration that during this whole process of change throughout successive geological periods the herbivora in question were subject to the attacks of carnivora which, in order to capture them must also have [[p. 336]] frequented the same muddy or hard ground as their prey, and whose feet must, therefore, have been exposed to the very same mechanical actions. Yet no similar modifications of the foot-structures have resulted, the reason clearly being that in their case the use of the claws was required, and therefore natural selection checked any tendency to the production of hoofs. Here we have a striking example of the superior power of natural selection over any mere mechanical causes of variation.
The great question of degeneration, of the relations of man to the tertiary mammalia, of the origin of mammalia and of birds, of consciousness as a factor in evolution, and many others, are discussed in a more or less effective manner in this very unequal volume, which we close with a feeling of regret that its talented author should have done himself the injustice of issuing in its present incomplete form.
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