EVOLUTION 195 



Man's Place in Nature. — Although we know that man is 

 separated mentally by a wide gap from all other animals, in our 

 study of physiology we must ask where we are to place man. If we 

 attempt to classify man, we see at once he must be placed with 

 the vertebrate animals because of his possession of a vertebral 

 column. Evidently, too, he is a mammal, because the young are 

 nourished by milk secreted by the mother and because his body 

 has at least a partial covering of hair. Anatomically we find that 

 we must place man with the apelike mammals, because of these 

 numerous points of structural likeness. The group of mammals 

 which includes the monkeys, apes, and man we call the primates. 



Although anatomically there is a greater difference between 

 the lowest type of monkey and the highest type of ape than there 

 is between the highest type of ape and the lowest savage, yet there 

 is an immense mental gap between monkey and man. 



Instincts. — Mammals are considered the highest of vertebrate 

 animals, not only because of their complicated structure, but be- 

 cause their instincts are so well developed. Monkeys certainly 

 seem to have many of the mental attributes of man. 



Professor Thorndike of Columbia University sums up their habits 

 of learning as follows : — 



" In their method of learning, although monkeys do not reach the 

 human stage of a rich life of ideas, yet they carry the animal method of 

 learning, by the selection of impulses and association of them with differ- 

 ent sense-impressions, to a point beyond that reached by any other of 

 the lower animals. In this, too, they resemble man ; for he differs from 

 the lower animals not only in the possession of a new sort of intelligence, 

 but also in the tremendous extension of that sort which he has in common 

 with them. A fish learns slowly a few simple habits. Man learns quickly 

 an infinitude of habits that may be highly complex. Dogs and cats learn 

 more than the fish, while monkeys learn more than the3^ In the number 

 of things he learns, the complex habits he can form, the variety of lines 

 along which he can learn them, and in their permanence when once formed, 

 the monkey justifies his inclusion with man in a separate mental genus." 



Evolution of Man. — Undoubtedly there once lived upon the 

 earth races of men who were much lower in their mental organiza- 

 tion than the present inhabitants. If we follow the early history 



