The human species

by A. de Quatrefages

It is different with the theories which favour gradual transmutation. They deal with all these important questions, and give a more or less plausible solution of them. They start from a certain number of principles whose consequences more or less explain the whole question and many of its details. In a word, they constitute genuine doctrines and it is but natural that they should have gained a certain number of adherents.

Unfortunately these theories all have the same radical fault. They agree with a certain number of important facts, connected essentially with the morphology of beings; but they are in direct contradiction with the fundamental phenomena of general physiology, which are no less general or fixed than the former. This contradiction is not evident at first sight. This is the reason why these doctrines have influenced not only the public at large, but even men of the highest intellect, whose sole error consists in their having allowed themselves to consider one side of the question only.

All these theories have been consolidated into the doctrine which rightly bears the name of Darwin. At the hands of this illustrious naturalist, the hypothesis of gradual transmutation has assumed a force and appearance of truth which it never possessed before. Doubtless, long before Darwin, Lamarck had formulated his law of heredity and his law of development of organs, to which the English naturalist has added nothing; M. Naudin had compared natural selection to artificial selection; Etienne Geoffroy St.-Hilaire had promulgated the principle of the balance of organs; Serres and Agassiz had recognized in embryogenic phenomena the representation of the genesis of beings. But by taking as a starting point the struggle for existence; by explaining in this manner selection; by fixing the results of heredity; by replacing the pre-established laws of Lamarck by the laws of divergence, continuity, permanent characters and of finite heredity; by giving by these means an explanation of the adaptation of beings to all the conditions of existence, the expansive power of some, the localisation of others, the successive modifications of all, under the dominion of the laws of compensation, economy and of correlation of increase; by applying these facts to the past, present and future of animate creation, Darwin has formed a complete and systematic theory, the whole, and often the details, of which it is impossible not to admire.

I understand the fascination exercised by this profound and ingenious conception, which is supported by immense knowledge, and ennobled by his loyal honesty. I should doubtless have yielded as so many others have done, if I had not long understood that all questions of this kind depend especially upon physiology. Now, my attention once aroused, I found no difficulty in recognising the point at which the eminent author quits the ground of reality and enters upon that of inadmissible hypothesis.

I have thought it right to publish my criticisms upon the theory of transmutation, and upon Darwinism in particular. I was authorised to do so by the numerous attacks which have often been made, in no measured terms, against what I consider to be the truth, and against every opponent of the new theory. But while refuting theories I have always respected the authors and done justice to their work. I have quoted the good as well as the bad, and have always held aloof from the ardent and lamentable polemics raised by transmutation.

I have had great pleasure, when occasion has offered, in defending the splendid researches made by Darwin in the natural sciences. For this very reason, and at the risk of being considered narrow minded, enslaved to prejudices and unable to leave an old groove, etc., etc., I consider myself entitled to attack Darwinism, if I employ none but the weapons of science.

III. There are some points in Darwinism which are perfectly unassailable. We may consider as the most important the struggle for existence, and selection which is the result of it. It is not the first time, certainly, that the former has been established, and the important part it has to play in the general harmony of the world has at least been partly comprehended. I will here only recall to the mind of my readers the fables of La Fontaine. But no one had insisted, as Darwin has done, upon the enormous disproportion which exists between the number of births and the number of living individuals; no one had investigated, as he has, the general causes of death or of survival which produce the final result. By pointing out the fact that each species tends to increase in number in geometrical progression, which is proved by the number of offspring to which a single mother can give birth during the whole course of her life, the English naturalist makes it easy to comprehend the intensity of the struggles, direct or indirect, which are undergone by animals and plants against one another and the surrounding world. It is, most certainly, entirely owing to this struggle for existence, that the whole world, in a few years, is not overrun by some species, or the rivers and ocean filled in the same manner.

It is no less evident to me that the survivors cannot always owe their preservation to a combination of happy chances. Among the immense majority the victory can only be due to certain special advantages, which are not enjoyed by those who succumb. The result of this struggle for existence is, then, the destruction of all the inferior individuals, and the preservation of those individuals only which possess some kind of superiority. This is what Darwin calls Natural Selection.