MIMICRY IN BIRDS 



Every student of the theory of natural selection 

 is familiar with the wonderful cases in which 

 some defenceless insect closely copies in its 

 appearance a quite unrelated form, which for 

 some reason or other — objectionable taste or 

 exceptional means of defence — appears to be 

 more immune from attack than the majority ; 

 but the cases of this "mimicry," as it is called, 

 among birds are not so well known, and it is 

 worth while here to review them in order to 

 be able to gain an idea as to how these remark- 

 able resemblances came about, in the case of 

 birds at all events. 



The best-known instance of mimicry in birds, 

 and the one most usually quoted, is the resem- 

 blance between certain orioles and friar-birds 

 in the islands of the Australian region. Friar- 

 birds are large honey-suckers, forming the genus 

 Tropidorhynchus of ornithologists. They are not 

 attractive in appearance, being of a dull snuffy- 

 brown colour, with some bare blackish skin about 

 the eyes. They are, however, unusually well 

 able to look after themselves. Being as big as 

 blackbirds, with sharp, curved beaks, and very 



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