Control of Heredity: Eugenics 287 



conditions, then a real experimental evolution will be possible; 

 if they cannot be so induced but are like the changes taking place 

 in the radium atom we can only look on while the evolutionary 

 processes proceed, selecting here and there a product which 

 nature gives us but being unable to initiate or control these pro- 

 cesses. 



' B. CONTROL OF HUMAN HEREDITY : EUGENICS 



^ 



I. PAST EVOLUTION OF MAN 



There is every evidence that man also, no less than domesti- 

 cated animals, has evolved from a natural or wild state. The 

 most primitive types of men are known only from a few fossil 

 remains, which indicate that these primitive men belonged to dif- 

 ferent species, and some of them even to different genera, from 

 Homo sapiens (Fig. 104). Later stages in the evolution of man 

 are known from many remains, implements and handiwork, as 

 well as from certain primitive races or tribes which have per- 

 sisted to the present time. The grades of culture represented by 

 these extinct or persistent tribes and by modern men are usually 

 classified as savagery, barbarism and civilization. There must 

 have been much greater evolution of human types during pre- 

 historic times than since the beginnings of civilization. The 

 physical, mental and moral changes which took place in men from 

 the earliest stages of savagery down to the beginnings of civili- 

 zation were very great, but they were nevertheless slight com- 

 pared 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 evolutionary changes in man have 

 been very small. Minor changes have occurred and are still going 

 on, as Osborn has shown in his "Cartwright Lectures on Contem- 

 porary Evolution in Man," but the species has remained relatively 

 stable during the historic epoch as compared with the much longer 

 prehistoric period. 



