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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