330 CHANGES IN THE HABITS OF BIRDS. 



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insect-food, with which they feed their young. They 

 build upon the ground in the grass, and their nests are 

 exposed in great numbers by the scythe of the mower, if 

 he begins haymaking early in the season. 



These birds, as well as robins, before America was set- 

 tled by the Europeans, and when the greater part of the 

 country was a wilderness, must have been comparatively 

 few. Though the bobolink consumes great quantities of 

 rice after the young are fledged and the whole family have 

 departed, it is not the rice-fields which have made its 

 species more numerous, but the increased abundance of 

 insect food in the North, where they breed, an increase 

 consequent upon the increased amount of tillage. The 

 robins are dependent entirely upon insect food, and must 

 have multiplied in greater proportion than the bobolinks. 

 There are probably thousands of both species at the pres- 

 ent day to as many hundreds that existed at the dis- 

 covery of America. Many other small birds, such as the 

 song-sparrow and the linnet, have increased nearly in 

 the same ratio with the progress of agriculture and the 

 settlement of the country. 



Domestication blunts the original instincts of animals 

 and renders birds partially indifferent to colors. It 

 changes their plumage as well as their instincts. In pro- 

 portion to the length of time any species has been domes- 

 ticated, it is unsafe to depend on the correctness of our 

 observation of their instincts with respect to colors. All 

 the gallinaceous birds, except the common hen, lay spec- 

 kled eggs. It is probable that during the thousands of 

 ages since the latter was domesticated her eggs have lost 

 their original marking and have become white. As great 

 a change has happened in their plumage, while the more 

 recently domesticated birds, like the turkey and guinea- 

 hen, retain more nearly their original markings. After 

 domestication birds no longer require to be protected from 



