SEXUAL SELECTION- 519 



even from above." °^ The crimson under tail-coverts of 

 some other birds, as with one of the woodpeckers, Picus 

 major, can be seen without any such display. The common 

 pigeon has iridescent feathers on the breast, and every one 

 must have seen how the male inflates his breast while court- 

 ing the female, thus showing them off to the best advantage. 

 One of the beautiful bronze-winged pigeons of Australia 

 {Ocyphaps lophotes) behaves, as described to me by Mr. 

 Weir, very differently: the male, while standing before the 

 female, lowers his head almost to the ground, spreads out 

 •and raises his tail, and half expands his wings. He then 

 alternately and slowly raises and depresses his body, so that 

 the iridescent metallic feathers are all seen at once, and 

 glitter in the sun. 



Sufficient facts have now been given to show with what 

 care male birds display their various charms, and this they 

 do with the utmost skill. "While preening their feathers, 

 they have frequent opportunities for admiring themselves, 

 and of studying how best to exhibit their beauty. But as 

 all the males of the same species display themselves in 

 exactly the same manner, it appears that actions, at first 

 perhaps intentional, have become instinctive. If so, we 

 ought not to accuse birds of conscious vanity; yet when 

 we see a peacock strutting about, with expanded and 

 quivering tail-feathers, he seems the very emblem of pride 

 and vanity. 



The various ornaments possessed by the males are cer- 

 tainly of the highest importance to them, for in some cases 

 they have been acquired at the expense of greatly impeded 

 powers of flight or of running. The African night-jar 

 (Cosmetornis), which during the pairing season has one of^ 

 its primary wing-feathers developed into a streamer of very 

 great length, is thereby much retarded in its flight, although 

 at other times remarkable for its swiftness. The "unwieldy 

 size" of the secondary wing-feathers of the male Argus 



9* "Birds of India," vol. ii. p. 96. 



