Mimicry 



away the pursuers sufficiently far, the female quietly slips 

 up to the nest and then drops in her egg. On the return 

 of the frightened birds, they either fail to notice the 

 addition to the nest, or are indifferent, finding the eggs 

 they left still whole." 



In Australia there is a remarkable case of bird 

 mimicry. The powerful friar-birds, which go about in 

 flocks, and are therefore less likely to meet with mishap 

 than if they lived alone or in pairs, are mimicked by 

 the harmless, solitary orioles, and this is good for the 

 orioles. Hawks hesitate to attack the orioles, for per- 

 chance they might be friar-birds, and the result of such an 

 attack would be unpleasant for the hawk. There are many 

 other examples of weak birds copying strong ones. The 

 fork-tailed cuckoo of India mimics the powerful king- 

 crow ; another Eastern cuckoo, the brain-fever bird, closely 

 resembles the Indian sparrow-hawk ; a bulbul copies a 

 shrike, and in each case the weaker bird benefits by the 

 resemblance, if only to the extent of misleading possible 

 enemies. 



On the other hand, very many birds of prey mimic 

 harmless birds, thereby gaining an easier livelihood than 

 if they appeared in their true colours. Just as the cuckoos 

 commonly mimic more powerful birds, so do many of the 

 hawks mimic harmless ones. An Indian hawk, for ex- 

 ample, closely resembles so typical a sea-bird as the tern. 

 The great skuas, again, though sea-birds, are also birds of 

 prey, and curiously enough some of them mimic eagles. 

 Why should one bird of prey mimic another bird of similar 

 habits ? But we are digressing into questions too abstruse 

 for a book of this nature ; in fact the whole question of 

 mimicry in birds is beset with difficulties. 



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