The human species

by A. de Quatrefages

Here we have another instance of the curious method of reasoning familiar to Darwinists. Microcephalism, idiotcy, and crétinism constitute so many teratological or pathological states. They belong, consequently, to the very numerous groups of facts which have long been studied. If some of these facts can be regarded as phenomena of atavism, why should it be otherwise with the rest? Why attribute to atavism a single character only in crétins and microcephali, and refer the other to teratology and pathology? This is evidently an entirely arbitrary kind of treatment, and as much opposed as possible to the true scientific method.

After the works of teratologists, after the experiments of Geoffroy, so ably resumed and completed by M. Dareste, the part played by pathogenic causes, even by external causes, in arrested development cannot be denied. Now microcephalism is nothing else than arrested development acting on the cranium and its contents. But this is not an isolated case. Other organs and functions in microcephali suffer in the same manner. They have been proved to be always sterile, and certainly sterility is not a phenomenon which can be referred to atavism.

Thus among microcephali a teratogenic cause is clearly proved to have acted on part of the organism, viz., the generative organs. What reason can be alleged for attributing alterations of the cranium and brain to an entirely different cause? By virtue of what principle can two facts be separated, which observation has shown to be so intimately connected with each other? Why should the first be appealed to as an argument and nothing said about the second? Is it not evident that this is an entirely arbitrary kind of procedure, and actuated solely by the requirements of theory?

The general plan of the brain is fundamentally the same in all the mammalia and in man. Upon this point, as upon every other, the resemblance is greatest when the latter is compared with the anthropomorphous apes. When, for some reason or other, his brain is altered and reduced, as in the microcephali, is it at all surprising that fresh resemblances should arise. The contrary would be unintelligible.

This is a fact upon which Vogt has especially insisted, and he has described from this point of view several interesting details which render less general some of the results obtained by M. Gratiolet. But it is a remarkable fact that these new relations are not established with the most highly developed apes, but with the tailed apes of the new world, with the platyrrhini, which are excluded by Haeckel and Darwin from the human ancestral series. Thus, the Darwinian theory itself protests against the comparison between the microcephali and our pretended pithecoid ancestors.

The relations which we are discussing do not, moreover, reach a similarity which would authorise the conclusions of the Genevese savant. The brains of microcephali, though often less voluminous and less convoluted than those of the anthropoid apes, according to Gratiolet, do not become at all similar to them. This proposition is confirmed by the work of Vogt.

The case is the same with the skeleton as with the brain. I will here appeal to an authority, which none of my adversaries can reject, that, namely, of Huxley. After having protested against the statements of those who declare “that the structural differences between man and apes are small and insignificant,” the eminent anatomist adds that “every bone of the gorilla bears a mark by which it can be distinguished from the corresponding human bone, and that, in the present state of creation at least, no intermediary being fills the gap which separates man from the troglodyte.” In the general conclusion of his book, Huxley moreover recognises the fact that the fossil human remains hitherto discovered do not indicate any approach towards the pithecoid form.

VIII. After the formal declarations of a naturalist, whose Darwinian convictions place him beyond all suspicion of partiality, how is it that we continually find the expression simian character employed à propos of the most insignificant modifications of some human type of which no one gives a precise description? It is, to say the least, an abuse of words, against which I have often protested. We have just seen that this expression assumes an anatomical fact which does not exist, and which, consequently, constitutes an error. It has, moreover, the inconvenience of being understood literally by the ignorant, and sometimes of deceiving even educated men, and of giving rise to a belief in imaginary degradations and comparisons.

In fact, man and the rest of the vertebrata are constructed upon the same fundamental plan. Between him and the other members of this group numerous relations exist. Organised beings are not crystals whose forms are mathematically defined; with the former the whole of the body and each part of this whole oscillate between limits whose extent has not yet been fixed, but which is at times considerable. By these very oscillations the customary relations are continually modified, not only between man and the apes, but between man and the rest of the vertebrata. If we compare man to any animal type whatever, if we apply the same method to this comparison, and the same terminology, we shall arrive at singular conclusions. I will quote a single example.

The most important fact in connection with the brain is certainly not its absolute development. It is the relation of this development to that of the rest of the body. The agreement upon this point, when animals are the subject of discussion, is general. It should be the same when the discussion is on man. Undoubtedly upon this ground of relative superiority or inferiority, upon which certain anthropologists so readily take their stand à propos of races or individuals, the relations of which I speak constitute one of the most striking and essential characters.