352 



A HISTORY OF BIRDS 



body so as to bring the trunk to a nearly vertical position, and 

 the neck is brought into a line with this when the head is bent 

 down, the beak resting among the neck feathers. The long 

 pendant occipital crest is then raised and spread out fan-wise 

 across the head, while the secondary quill feathers are thrust 

 forwards, and the belly feathers are set on end. Simultane- 

 ously the bird struts up and down with a peculiar mincing gait 

 as though swollen with importance and intending to make the 

 most of his charms. No other bird, so far as I am aware, 



III. 35. — The Sun-Bittern in Display 



displays after this fashion. Some of the Cranes may do so, 

 but the fact has not been recorded. 



How then stands the sexual selection theory at the present 

 day, at any rate as applied to birds ? 



The evidence seems to suggest that the evolution of re- 

 splendent plumage is not to be attributed to the effect of the 

 selective action of the female, — -to the choice, by the female, of 

 the most effectively coloured among her suitors. This develop- 

 ment of colour, or of decorative plumage of any kind, of second- 

 ary sexual characters in short, must be regarded, apparently, as 



