450 V. THE NATURE OF EVOLUTION 



and cancer is also increasing strikingly. 



Overspecialized animals, in general, appear to have become extinct 

 with the unusual development of bodily size. Likewise mankind 

 seems to be bound to become extinct in a near future as did the rep- 

 tiles. However, uncivilized people who can remain small in stature 

 Avith a high resistance to virus diseases owing to the absence of stimu- 

 lating climate in their abode, which inhibits the promotion of civiliza- 

 tion, maj' escape the extinction and will represent the mankind when 

 the civilized are extinct. 



