Mimicry in Birds 



of the brain-fever bird to the shikra. We can 

 see why it pays this cuckoo to look like the hawk, 

 but there is a very curious little point which makes 

 the fortuitousness of the "mimicry" almost certain. 

 Many hawks have a little tubercle just inside the 

 nostril, and this is reproduced in the brain-fever 

 bird. But setting aside the improbability of a 

 terrified bird stopping to notice whether the 

 object of its fear had tubercles in the nostrils 

 or not — in which case, too, it could not fail to see 

 the different beak — it so happens that the shikra 

 itself does not possess this little nasal prominence! 

 Thus the possession thereof by the cuckoo is 

 a mere chance coincidence, and if this be the 

 case with such a small detail, why may not the 

 resemblance of plumage and form be so likewise ? 

 As a matter of fact, the cuckoos as a family are 

 very prone to show resemblances to birds of prey. 

 For instance, a common Indian non - parasitic 

 ground-cuckoo (Centropus sinensis), whose want 

 of resemblance to a hawk when adult may be 

 judged from its popular name of "crow-pheasant," 

 is usually, when young, barred across with black 

 and white and black and brown, and with its 

 strong curved bill and bright eyes distinctly re- 

 calls a young bird of prey. Here, then, we have 

 the requisites for a case of mimicry. Not all 

 young crow-pheasants have the barred plumage ; 



some are black with brown wings, — simply duller 



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