The Making of Species 
In every work on animal colouration numbers of 
such cases are cited. 
We may grant that in some cases, at any rate, 
the resemblance is of value to its possessor, in 
that it deceives predatory creatures. But it does 
not follow from this that the likeness has origi- 
nated through the action of natural selection. In 
order that there can be selection there must be 
varying degrees of a tolerable resemblance to 
select from. How did the initial similarity 
arise? This is a matter upon which Wallaceians 
are silent. As Poulton truly says, in discussing 
the degree of protection afforded by such re- 
semblances, we tacitly endow animals with senses 
exactly similar to our own. Are we justified in 
so doing? Most certainly not in the case of the 
invertebrate animals, especially as regards the 
arthropods, of which the eyes are constructed 
very differently from those of human beings. 
D. Dewar has often seen a toad shoot out 
its tongue and touch a lighted cigarette end, 
apparently mistaking it for an insect. Similarly, 
he has again and again induced a gecko lizard to 
chase and try to swallow a piece of black cotton, 
one end of which was rolled up into a ball. It is 
only necessary to take hold of the unrolled end 
of the cotton and place the rolled-up end a few 
inches from the lizard, and gradually draw it 
away in order to induce the lizard to attempt to 
seize it. 
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