Mimicry in Birds 



pheasant, and suggests that this similarity is 

 useful to the bird. But the resemblance is not 

 very close, and as this cuckoo is not parasitic and 

 has a very strong bill of its own, there seems 

 to be no reason why it should not be able to 

 maintain itself without a disguise. 



Another set of small Eastern cuckoos have 

 barred brown plumage, at any rate when young, 

 which is much like that of young shrikes, and 

 there are a cuckoo (Penthoceryx sonnerati) and 

 a shrike (Lanius tigrinus) which always keep 

 their zebra plumage. As shrikes are fierce little 

 birds and uncommonly hard biters, and also 

 wary and intelligent, the cuckoos may profit by 

 wearing their livery. 



In Madagascar we find shrikes copied by 

 other Passerine birds, much as the orioles 

 resemble the friar-birds. The shrike Xenopiros- 

 tris pollcni is exactly copied by the harmless 

 Bulbul Tylas eduardi, and it is particularly 

 noteworthy that both birds vary in the same 

 way, the breast of each being indifferently white 

 or buff. 



Having considered the cases in which a weaker 

 bird copies a stronger one, we may turn to the 

 "aggressive" mimicry of harmless birds by birds 

 of prey which would be given a wide berth if 

 their real character were known. 



The oldest known case of this kind is that 



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