DOMESTICATED BIRDS 187 



brought to the service of man, has been permitted to return 

 to its ancestral wild life. 



The most striking and by far the most interesting quality 

 exhibited by our birds is found in their sympathetic motive. 

 In this spiritual quality, so far as it relates to their own kind, 

 the feathered creatures are clearly in advance of all other spe- 

 cies, including even man. A single fact, one of great gener- 

 ality, will serve to make this statement clear. Among the 

 birds we find the only cases of true marriage which are known 

 in the animal kingdom. In the greater number of the species 

 the union is for a season, but among many it is for life. In 

 the case of certain varieties of paroquets, the union is so 

 indissoluble that, according to common report, a report which 

 seems much better verified than the most of those concerning 

 the habits of animals, neither member of the pair will survive 

 the death of the other. Man, with all his striving towards 

 a better social state, has, as a whole, not yet attained to the 

 enduring affection for the mate which is evinced by the greater 

 part of the birds. 



In this same connection, we may note that the aesthetic 

 appreciation among the birds appears to have attained a far 

 higher level than it has won in any other creatures. There 

 can be little doubt that the exquisitely beautiful plumage, the 

 unparalleled shapeliness of form and grace of carriage, as well 

 as the melodies which are uttered by so many species, all owe 

 their development to a process of sexual selection which has 

 led the discerning females to prefer the more ornamental of 

 the males who sought them as partners. If any one will 

 examine the exquisite shapes and gradations of color which 

 are exhibited in the tail of the peacock, or of the lyre-bird, or 

 even the coloration of the game-cock, he may perhaps imagine 



