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ON SEXUAL SELECTION AND THE .ESTHETIC 

 SENSE IN BIRDS. 



By H. E. Howard, F.Z.S. 



Peculiarities in the development of the plumage of different 

 birds, together with eccentricities of behaviour during the mating 

 period, which from time to time have come under my notice, 

 have raised doubts in my mind as to the efficiency of sexual 

 selection — in the way in which Mr. Darwin interpreted it — to 

 account for phenomena in the development of plumage, &c, to 

 which it has been applied. Mr. Darwin, in his ' Descent of 

 Man,' has paid much attention to the colours of birds, their 

 plumage, and its display at the pairing season ; and it is on 

 this latter circumstance that he founds his theory, that both the 

 plumage and the colours have been developed by the preference 

 of the females, the more ornamented males becoming the parents 

 of each successive generation. Many cases of the actual display 

 are given, nearly all of which are in reference to species in 

 foreign countries ; those that do refer to this country are on the 

 evidence of one observer, and on species kept in confinement. I 

 therefore propose to give more or less in detail — and it is neces- 

 sary for the purposes of my argument — cases of actual display 

 amongst some of our native species. I feel convinced that, if it 

 were not for the difficulties inseparable from watching a display 

 so quickly executed, some such display as I am about to relate 

 would be found to be inherent in the males, occasionally perhaps 

 in the females, of all species. 



The males then, as I have seen them, have three different 

 ways in which they can display their beauties to the female : they 

 can display the colours of their plumage and any special orna- 

 ments which they possess, they can display their vocal powers, 

 and they can display the beauties of their form ; this latter per- 

 haps needs some explanation. The most perfect development 

 of plumage amongst all birds is reached in the spring, immedi- 



