Survival of the Fittest. 439 



inhabitants of a country are struggling together with nicely- 

 balanced forces, extremely-slight modifications in the 

 structure or habits of one species would often give it an 

 advantage over others ; and still further modifications, so 

 long as the species continued under the same conditions of 

 life and profited by similar means of subsistence and defence, 

 would often still further augment the advantage. No coun- 

 try can be mentioned whose native inhabitants are now so 

 perfectly adapted to each other and to their environment that 

 none could be better adapted and improved, for in all coun- 

 tries the natives have been so far conquered by naturalized 

 productions as to have allowed them to take firm possession 

 of the land. And as foreigners have thus in every country 

 beaten some of the natives, it may be safely concluded that 

 the latter might have been modified with profit so as to have 

 better resisted the intruders. 



A man by his methodical and unconscious means of 

 selection can produce and has produced great results. 

 What may not Natural Selection effect? Man can only 

 operate on external and visible characters, but nature cares 

 nothing for appearances, except in so far as they are bene- 

 ficial to any being. ' She can act on every internal organ, 

 on every shade of constitutional difference and, in fine, on 

 the entire machinery of life. Man selects exclusively for 

 his own advantage, but nature solely for that of the being 

 she tends, and under her judicious selection the slightest 

 difference of structure or constitution may well turn the 

 nicely-balanced scale in the Struggle for Existence, and thus 

 be preserved. As fleeting as are the wishes and efforts of 

 man, and as short as is his earthly career, so poor, therefore, 

 must be the results which he accomplishes when compared 

 with those accumulated by nature during whole geological 

 periods. Is it a wonder, then, that her productions should 

 be far truer in character than man's, and that they should be 

 infinitely better adapted to the most complex conditions of 

 life and should bear the stamp of far higher workmanship ? 



