The solitary life of the Orang-utan has already been noted. As regards Gorillas, Dr. Savage states that there is only one adult male attached to each group;[206] and Mr. Reade says expressly that they are not gregarious, though they sometimes seem to assemble in large numbers.[207] Both Mr. Du Chaillu[208] and Herr von Koppenfels[209] assure us likewise that the Gorilla generally lives in pairs or families. The same is the case with the Chimpanzee. “It is seldom,” Dr. Savage says, “that more than one or two nests are seen upon the same tree or in the same neighbourhood; five have been found, but it was an unusual circumstance. They do not live in ‘villages’.... They are more often seen in pairs than in gangs.... As seen here, they cannot be called gregarious.”[210] This statement, confirmed or repeated by Mr. Du Chaillu[211] and Professor Hartmann,[212] is especially interesting, as the Chimpanzee resembles man also in his comparatively slight strength and courage, so that a gregarious life might be supposed to be better suited to this animal. Mr. Spencer, however, has pointed out that not only size, strength, and means of defence, but also the kind and distribution of food and other factors must variously co-operate and conflict to determine how far a gregarious life is beneficial, and how far a solitary life.[213] Considering, then, that, according to Dr. Savage, the Chimpanzees are more numerous in the season when the greatest number of fruits come to maturity,[214] we may almost with certainty infer that the solitary life generally led by this ape is due chiefly to the difficulty it experiences in getting food at other times of the year. Is it not, then, most probable that our fruit-eating human or half-human ancestors, living on the same kind of food, and requiring about the same quantities of it as the man-like apes, were not more gregarious than they? It is likely, too, that subsequently, when man became partly carnivorous, he continued, as a rule, this solitary kind of life, or that gregariousness became his habit only in part. “An animal of a predatory kind,” says Mr. Spencer, “which has prey that can be caught and killed without help, profits by living alone: especially if its prey is much scattered, and is secured by stealthy approach or by lying in ambush. Gregariousness would here be a positive disadvantage. Hence the tendency of large carnivores, and also of small carnivores that have feeble and widely-distributed prey, to lead solitary lives.”[215] It is, indeed, very remarkable that even now there are savage peoples who live rather in separate families than in tribes, and that most of these peoples belong to the very rudest races in the world.[216]