HUMAN LIFE 



species hard pressed to exist in its native 

 habitat, may release it from the too 

 severe rigors of a destructive climate, 

 or take it beyond the habitat of its 

 most dangerous enemies, or give it the 

 needed space and food for the support 

 of a numerous progeny. Thus, such a 

 single phenomenon as migration might 

 ameliorate any one or more of the sev- 

 eral phases of the struggle for exist- 

 ence. 



Again, the adoption by two widely dis- 

 tinct and perhaps originally antagonistic 

 species of a commensal or symbiotic 

 life, based on the mutual-aid principle- 

 thousands of such cases are familiar to 

 naturalists would ameliorate or abolish 

 the inter-specific struggle between these 

 two species. Even more effective in the 

 modification of the influence due to a bit- 

 ter struggle for existence, is the adoption 

 by a species of a social or communistic 

 mode of existence so far as its own in- 

 dividuals are concerned. This, of course, 

 would largely ameliorate for that species 

 56 



