376 TROPICAL NATURE 



tion, and what may be termed male selection, will tend to 

 give them the advantage in the struggle for existence, and 

 thus the fullest plumage and the finest colours will be trans- 

 mitted, and tend to advance in each succeeding generation. 



Theory of Display of Ornaments by Males 



The full and interesting account given by Mr. Darwin of 

 the colours and habits of male and female birds (Descent of 

 Man, chaps, xiii. and xiv.), proves that in most, if not in 

 all cases, the male birds fully display their ornamental plum- 

 age before the females or in rivalry with each other ; but on 

 the essential point of whether the female's choice is deter- 

 mined by minute differences in these ornaments or in their 

 colours, there appears to be an entire absence of evidence. 

 In the section on " Preference for particular Males by the 

 Females," the facts quoted show indifference to colour, except 

 that some colour similar to their own seems to be preferred. 

 But in the case of the hen canary who chose a greenfinch in 

 preference to either chaffinch or goldfinch, gay colours had 

 evidently no preponderating attraction. There is some evi- 

 dence adduced that female birds may, and probably do, 

 choose their mates, but none whatever that the choice is 

 determined by difference of colour ; and no less than three 

 eminent breeders informed Mr. Darwin that they " did not 

 believe that the females prefer certain males on account of 

 the beauty of their plumage." Again, Mr. Darwin himself 

 says : " As a general rule colour appears to have little influ- 

 ence on the pairing of pigeons." The oft-quoted case of Sir 

 R. Heron's pea-hens, which preferred an '"old pied cock" to 

 those normally coloured, is a very unfortunate one, because 

 pied birds are just those that are not favoured in a state of 

 nature, or the breeds of wild animals would become as varied 

 and mottled as our domestic varieties. If such irregular 

 fancies were not rare exceptions, the production of definite 

 colours and patterns by the choice of the female birds, or in 

 any other way, would be impossible. 



There remains, however, to be accounted for, the remark- 

 able fact of the display by the male of each species of its 

 peculiar beauties of plumage and colour a display which Mr. 



