The Making of Species 



ment. The hunted creatures are thereby the 

 better able to elude the vigilance of their foes, 

 while those that hunt are in a position to take 

 their quarry by surprise ; so that natural selection 

 has caused them all to assimilate to the hues 

 of their surroundings. Neo-Darwinians point 

 to the fact that some Arctic animals are brown 

 in the summer to match the ground from 

 which the snow has melted, and turn white in 

 winter to assimilate with their snowy background. 

 Naturalists further cite, as evidence in favour of 

 this theory, the case of those creatures which 

 imitate inanimate objects, such as leaves and 

 twigs, and thereby escape the observation of 

 their foes. 



Thus, the great majority of animals are sup- 

 posed to be cryptically coloured, that is to say, 

 coloured so as to be, if not quite invisible, 

 at least very inconspicuous in their natural 

 habitat. 



It is, however, generally admitted that many 

 creatures are not cryptically coloured. Some, 

 indeed, seem to be coloured in such a way as to 

 render them as conspicuous as possible. The 

 Neo-Darwinians declare that there is a reason 

 for this. "If," writes Professor Milnes Marshall 

 (page 133 of his Lectures on the Darwinian 

 Theory], " an animal, belonging to a group liable 

 to be eaten by others, is possessed of a nauseous 

 taste, or if an animal, such as a wasp, is specially 



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