Man m the Light of Evolution 



years the Individuals possessing this peculiarity 

 would become very numerous, and the descend- 

 ants of less favored individuals would be out- 

 numbered, if the number of survivors in the 

 whole species remained constant. So great an 

 advantage would very rarely occur. But it is 

 evident that the very slightest advantage contin- 

 ued from year to year would markedly increase 

 the number of individuals attaining maturity. 

 Any continued change In conditions will favor 

 the survival of descendants of forms whose in- 

 dividual characteristics are best adapted to the 

 new surroundings. In the long run those best 

 adapted to their environment will survive and 

 develop, attain maturity, and hand down their 

 characteristics to the largest number in the next 

 generation. The rest will die at various stages 

 of Immaturity and be prevented from breeding. 

 It is evident that there Is and must be a uni- 

 versal process of natural selection corresponding 

 to the artificial selection of the breeder of domes- 

 tic animals. This process tends to accumulate 

 variations from generation to generation. Its 

 results will probably be far slower and more 

 gradual than the breeder's artificial selection, but 

 for the same reason they may be more sure and 



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