The Theory of Sexual Selection. 383 



about the same area as the play-house. The flowers 

 are said to be removed when they fade, while fresh 

 ones are gathered to supply their places. Thus the 

 garden is always kept bright with flowers, as well as 

 with the brilliant green of mosses, which are col- 

 lected and distributed in patches, resembling tiny 

 lawns. 



Now these sundry cases alone seem to prove a high 

 degree of the aesthetic sense as occurring among 

 birds ; for, it is needless to say, none of the facts just 

 mentioned can be due to natural selection, seeing that 

 they have no reference to utility, or the preservation 

 of life. But if an aesthetic sense occurs in birds, we 

 should expect, on a priori grounds, that it would 

 probably be exercised with refere'nce to the personal 

 appearance of the sexes. And this expectation is 

 fully realized. For it is an observable fact that in 

 most species of birds where the males are remarkable 

 for the brilliancy of their plumage, not only is this 

 brilliancy most remarkable during the pairing season, 

 but at this season also the male birds take elaborate 

 pains to display their charms before the females. 

 Then it is that the peacock erects his tail to strut 

 round and round the hens, taking care always to 

 present to them a front view, where the coloration is 

 most gorgeous. And the same is true of all other 

 gaily coloured male birds. During the pairing 

 season they actively compete with one another in 

 exhibiting their attractiveness to the females ; and in 

 many cases there are added all sorts of extraordinary 

 antics in the way of dancings and Growings. Again, 

 in the case of all song-birds, the object of the singing 

 is to please the females ; and for this purpose the 



