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. 
11. 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.” 
50 
