 | Sir Norman Lockyer - 1882 - 720 páginas
...important as corporeal structures for the welfare of each species, under its present conditions of life. Under changed conditions of life, it is at least possible...accumulating variations of instinct to any extent that was profitable. It is thus, I believe, that all the most complex and wonderful instincts have originated."... | |
 | 1898 - 476 páginas
...Bulletin No. 2. Scientific Series No 1. 1898. IN discussing the problem of Instinct, Darwin wrote, "If it can be shown that instincts do vary ever so...accumulating variations of instinct to any extent that was profitable." This sentence might well serve as the text for the charming book before us, and seems... | |
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Under changed conditions of life, it is at least possible that slight modifications of instinct might be profitable to a species; and if it can be shown that instincts do vary ever so little, then I can see no difficulty in natural selection preserving... 
