Mimicry Among Animals 



which we should be otherwise almost sir 

 over as insignificant or unimportant. 



The adaptation of the external colouring of 

 animals to their conditions of life has long been 

 recognized, and has been imputed either to an 

 originally created specific peculiarity, or to the 

 direct action of olimate, soil, or food. Where 

 the former explanation has been accepted, it has 

 completely checked inquiry, since we could n 

 get any further than the fact of the adaptation. 

 There was nothing more to be known about the 

 matter. The second explanation was soon found 

 to be quite inadequate to deal with ail the v 

 phases of the phenomena, and to be contradicted 

 by many well-known facts. For example, wild 

 rabbits are always of gray or brown tints well 

 suited for concealment among grass and fern. 

 But when these rabbits arc domesticated, with- 

 out any change of climate or food, they vary 

 into white or black, and these varieties may be 

 multiplied to any extent, forming white or black 

 races. Exactly the same thing has occurred 

 with pigeons; and in the case of rats and mice, 

 the white variety has not been shown to be at all 

 dependent on alteration of climate, food or other 

 external conditions. In many cases the wings 

 of an insect not only assume the exact tint of the 

 bark or leaf it is accustomed to rest on, but the 

 form and veining of the leaf i »r the exad rugosity 

 of the bark is imitated; and these detailed modi- 

 fications cannot be reasonably imputed to climate 

 or food, since in many cases the species docs not 

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