458 RECAPITULATION. 



theory. How strange it is that a bird, under the form of a 

 woodpecker, should prey on insects on the ground; that 

 upland geese, which rarely or never swim, should possess 

 webbed feet ; that a thrush-like bird should dive and feed on 

 sub-aquatic insects ; and that a petrel should have the habits 

 and structure fitting it for the life of an auk ! and so in 

 endless other cases. But on the view of each species con- 

 stantly trying to increase in number, with natural selection 

 always ready to adapt the slowly varying descendants of 

 each to any unoccupied or ill-occupied place in nature, these 

 facts cease to be strange, or might even have been 

 anticipated. 



We can to a certain extent understand how it is that 

 there is so much beauty throughout nature ; for this may be 

 largely attributed to the agency of selection. That beauty, 

 according to our sense of it, is not universal, must be 

 admitted by every one who will look at some venomous 

 snakes, at some fishes, and at certain hideous bats with a 

 distorted resemblance to the human face. Sexual selection 

 has given the most brilliant colors, elegant patterns, and 

 other ornaments to the males, and sometimes to both sexes, 

 of many birds, butterflies, and other animals. With bird* 

 it has often rendered the voice of the male musical to the 

 female, as well as to our ears. Flowers and fruit have been 

 rendered conspicuous by brilliant colors in contrast with the 

 green foliage, in order that the flowers may be easily seen, 

 visited and fertilized by insects, and the seeds disseminated 

 by birds. How it comes that certain colors, sounds, and 

 forms should give pleasure to man and the lower animals, 

 that is, how the sense of beauty in its simplest form was 

 first acquired, we do not know any more than how certain 

 odors and flavors were first rendered agreeable. 



As natural selection acts by competition, it adapts and 

 improves the inhabitants of each country only in relation 

 to their co-inhabitants ; so that we need feel no surprise at 

 the species of any one country, although on the ordinary 

 view supposed to have been created and specially adapted 

 for that country, being beaten and supplanted by the 

 naturalized productions from another land. Nor ought we 

 to marvel if all the contrivances in nature be not, as far as 

 we can judge, absolutely perfect, as in the case even of the 

 human eye ; or if some of them be abhorrent to our ideas of 

 fitness. We need not marvel at the sting of the bee, when 

 used against an enemy, causing the bee's own death; at 



