CHAPTER VI. 



Natural Selection (continued) — The Frequency of Natural Variations in Man — 

 The Influence of Natural Selection on the Mental Side of Man. 



Since natural selection deals with natural variations (for in 

 this process unfavourable variations are weeded out, while 

 favourable variations stand the best chance of survival), it is 

 worth while inquiring how far these occur in the human 

 race. 



It is well known that variations are far more common 

 among domestic animals than their wild congeners. Animals 

 in the wild state become by degrees adapted to their E, which, 

 be it noted, varies but little from generation to generation ; 

 it possesses, namely, the important element of stability, and 

 more or less perfect adaptation to a stable form of E is only 

 a matter of time. When, however, a wild animal is domes- 

 ticated, the E is suddenly altered, and variations appear in 

 abundance. The E now differs in two respects : in the first 

 place it is far more complicated, in the second it is more 

 unstable from generation to generation. In spite of the 

 greater complexity, however, we may safely assert that more 

 or less perfect adaptation would sooner or later occur — the 

 variations becoming less in number and degree — if only the E 

 remained exactly the same during several successive genera- 

 tions. 



We may be sure that variations are not so abundant among 

 savage races as among civilized peoples, because the E is both 

 more simple and more stable, being, in fact, more or less 

 identical during successive generations. How different is the 

 case of civilized peoples ! Not only is their E infinitely more 

 complex, it is also immeasurably more unstable. The com- 

 plexity of the social fabric increases pari passio with the 

 division of labour, each special calling having its own par- 



