408 HEREDITY AND ENVIRONMENT 



fossil remains, which indicate that these primi- 

 tive men belonged to different species, and 

 some of them even to different genera, from 

 Homo sapiens (Fig. 96). Later stages in the 

 evolution of man are known from many re- 

 mains, implements and handiwork, as well as 

 from certain primitive races or tribes which 

 have persisted to the present time. The grades 

 of culture represented by these extinct or per- 

 sistent tribes and by modern men are usually 

 classified as savagery, barbarism and civiliza- 

 tion. There must have been much greater evo- 

 lution of human types during prehistoric times 

 than since the beginnings of civilization. The 

 physical, mental and moral changes which took 

 place in men from the earliest stages of sav- 

 agery down to the beginnings of civilization 

 were very great, but they were nevertheless 

 slight compared with the tremendous changes 

 which must have occurred in those long ages 

 before the ancestors of man actually became 

 men. Within the historic period the evolution- 

 ary changes in man have been very small. 

 Minor changes have occurred and are still go- 

 ing on, as Osborn has shown in his "Cartwright 



