^08 TROPICAL NATURE, AND OTHER ESSAYS. 



colours and habits of male and female birds [Descent of 

 Man, Chapters xiii. and xiv.), proves that in most, if 

 not in all cases, the male birds fully display their orna- 

 mental plumage before the females or in rivalry with 

 each other ; but on the essential point of whether the 

 female's choice is determined by minute differences in 

 these ornaments or in their colours, there appears to be 

 an entire absence of evidence. In the section on '^Pre- 

 ference 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 evidence adduced that female birds may, and pro- 

 bably 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 cer- 

 tain males on account of the beauty of their plumage." 

 Again, Mr. Darwin himself says : "As a general rule 

 colour appears to have little influence on the pairing 

 of pigeons." The oft-quoted case of Sir E. 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 produc- 

 tion 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 



