SCIENCE AND REVOLUTION 



and their environment, leading to the survival of 

 those which were best equipped for this struggle 

 by superior powers of adaptation to the conditions 

 surrounding them. These produced an offspring 

 well adapted to continue the struggle under the 

 same conditions and in their turn to transmit their 

 qualities to their progeny by means of heredity, 

 while the organisms not well adapted to their 

 conditions of life were eliminated from the line 

 of evolution. 



One of the most significant results of this trans- 

 formist theory was that it wiped out the line of 

 demarcation, not only between the various 

 animal species, but also between animals and 

 plants. In his first work, Darwin had left the 

 question of man's descent open, from considera- 

 tions of expediency. But when Wallace, Huxley, 

 Haeckel, and others showed that " in every vis- 

 ible character, man differs less from the higher 

 apes than these do from the lower members of 

 the same order," Darwin assented and came forth 

 with his " Descent of Man," in which he indicated 

 the evolution of man and the anthropoid apes 

 from a common man-like ancestor. 



Simultaneously with Wallace and Darwin, Her- 

 bert Spencer appeared upon the scene, supple- 

 menting and perfecting their work by a complete 



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