The Making of Species 



small variations upon which to work. In such 

 circumstances the mills of natural selection may 

 grind surely, but they must grind very slowly. 



1 1. We must bear in mind that the struggle for 

 existence is most severe among young animals, 

 among creatures that are not fully developed. 

 Nature pays no attention to potentialities. The 

 weak go to the wall in the conflict, even though, 

 if allowed time, they might develop into prodigies 

 of strength. 



Moreover, and this is an important point, death 

 in the case of young creatures overtakes broods 

 and families rather than individuals. 



The above-cited objections to the theory that 

 species have originated by the action of natural 

 selection on minute variations, are mostly of a 

 general nature ; let us now notice briefly a few 

 more concrete objections. We shall not devote 

 much space to these in the present chapter, since 

 we shall be continually confronted with them 

 when dealing with the subject of animal colouring. 



12. Natural selection, as we shall see, fails to 

 account for the origin of what is known as pro- 

 tective mimicry. Some insects look like inanimate 

 objects, others resemble other insects which are 

 believed or known to be unpalatable. Those 

 creatures displaying this resemblance to other 

 objects or creatures, and deriving profit therefrom, 

 are said to " mimic " the objects or creatures 

 they copy. They are also called " Mimics." 



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