The Making of Species 



the still earlier progenitors of these two species, 

 we should probably see the adults dark-coloured. 

 I infer that this would be the case, from the 

 analogy of many other birds, which are dark 

 whilst young, and when adult are white ; and 

 more especially from the adult of the Ardea 

 gularis, the colours of which are the reverse 

 of those of A. asha, for the young are dark- 

 coloured and the adults white, the young having 

 retained a former state of plumage. It appears, 

 therefore, that the progenitors in their adult con- 

 dition of the A. as ha, the Buphus, and of some 

 allies have undergone, during a long line of 

 descent, the following changes of colour : firstly 

 a dark shade, secondly pure white, and thirdly, 

 owing to another change of fashion (if I may so 

 express myself), their present slaty, reddish or 

 golden-buff tints. These successive changes are 

 intelligible only on the principle of novelty 

 having been admired by the birds for the sake 

 of novelty." 



This reasoning may appear far-fetched and un- 

 convincing. It seems, however, quite likely that 

 the hen may select as her mate the suitor who 

 is conspicuously different from the others, not 

 because she admires novelty, but because his 

 conspicuousness attracts her attention and en- 

 ables her to make up her mind quickly to take 

 him and thus rid herself of the other troublesome 

 admirers, who are all very much alike. 



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