CHAPTER XI.
ORIGIN OF THE HUMAN SPECIES.—DIFFERENT HYPOTHESES.
I. The preceding chapter might enable me to dispense with a discussion of the applications which have been made of Darwinism to the history of man. Nevertheless, apart from the curious points in the subject itself, some discussion of it will be necessary, for it will not be devoid of instruction.
Lamarck endeavoured to show how, by means of his theory of habit, it was possible to conceive the direct transmutation of the chimpanzee into man. The Darwinists also agree in connecting man with the apes. Nevertheless none of them point out any of the species at present existing as our immediate ancestor; on this point they differ from their illustrious predecessor. It might be supposed that Vogt had determined this point if we take literally some passages of his Leçons sur l’homme. But the Genevese savant has clearly expressed his theory in his Mémoire sur les Microcéphales. He carries back the point of departure common to the two types to an anterior ancestor. Darwin, Wallace, Filippi, Lubbock, Haeckel, etc., connect man still more closely with the apes. The latter states his conclusions in the following terms:—
“The human race is a branch of the catarrhine group; he was developed in the old world, and sprang from apes of this group, which have long been extinct.”
II. Vogt disagrees with his scientific colleagues in an important point. He admits that different simian stocks may have given rise to different human groups. The populations of the old and the new world would thus be descendants of the different forms which are peculiar to the two continents. On this hypothesis, Australia and Polynesia, where there never have been apes, must necessarily have been peopled by means of migration.
The eminent professor of Geneva, moreover, always confines himself to a somewhat vague statement of his ideas relative to the genealogies which he thinks fit to attribute to the different groups of mankind.
III. Darwin and Haeckel have been bolder. The former has published an important work upon the Descent of Man, and the latter in his History of the Creation of Organised Beings has treated the same subject in detail, and given the genealogical table of our supposed ancestors, starting from the most simple known animals. The master and the disciple agree almost invariably, and it is to Haeckel himself that Darwin refers the reader who is curious to know the human genealogy in detail. Let us glance rapidly at the origin assigned to us by the German naturalist.
Haeckel considers as the first ancestor of all living beings the monera, which are nothing more than the amœbæ as understood by Dujardin. From this initial form man has reached the state in which we now find him, by passing through twenty-one typical transitory forms. In the present state of things our nearest neighbours are the anthropomorphous or tailless catarrhine apes, such as the orang, the gorilla, the chimpanzee, etc. All are sprung from the same stock, from the type of the tailed catarrhine apes, the latter are descended from the prosimiæ, a type which is now represented by the macaucos, the loris, etc. Next come the marsupials, which form the 17th stage of our evolution; further examination is useless.
Although the distance between anthropomorphous apes and man appears to be but small to Haeckel, he has nevertheless thought it necessary to admit the existence of an intermediate stage between ourselves and the most highly developed ape. This purely hypothetical being, of which not the slightest vestige has been found, is supposed to be detached from the tailless catarrhine apes, and to constitute the 21st stage of the modification which has led to the human form, Haeckel calls it the ape-man, or the pithecoid man. He denies him the gift of articulate speech as well as the development of the intelligence and self-consciousness.
Darwin also admits the existence of this link between man and apes. He says nothing as to his intellectual faculties. On the other hand he traces out his physical portrait, basing his remarks upon a certain number of exceptional peculiarities observed in the human species, which he regards as so many phenomena of partial atavism. “The earliest ancestors of man,” he says, “were without doubt once covered with hair; both sexes having beards; their ears were pointed and capable of movement; and their bodies were provided with a tail having the proper muscles. Their limbs and bodies were acted on by many muscles, which now only occasionally reappear in man, but which are still normally present in the quadrumana. The great artery and nerve of the humerus ran through a supracondyloid foramen. At this, or some earlier period, the intestine gave forth a much larger diverticulum or cœcum than that now existing. The foot, judging from the condition of the great toe in the fœtus, was then prehensile, and our progenitors, no doubt, were arboreal in their habits, frequenting some warm forest-clad land; the males were provided with canine teeth which served as formidable weapons.”