The Making of Species 



black-spotted, yellow under-surface may have 

 some protective value in the water. Neither 

 the pike nor the common European water-tortoise 

 will eat this newt. 



Toads are nearly all very inconspicuous ; 

 nevertheless they are well protected by the acrid 

 secretion from the skin glands ; moreover, they 

 are both recognised and avoided by those pre- 

 dacious creatures to whom they are distasteful. 

 Hawks, although as a rule plainly coloured, are 

 certainly recognised by all other birds. It would 

 seem, therefore, that "warning colours," like the 

 similar striking hues of many domestic animals, 

 are incidental attributes. It has been possible 

 for their owners to develop them, because for the 

 most part let alone. 



Eisig, long ago, pointed out that the brightly 

 coloured pigment in the skin of these warningly 

 coloured insects is in certain cases of an excretory 

 nature. Therefore the inference which should be 

 drawn is, as Beddard points out on page 173 of 

 his Animal Colouration, " that the brilliant 

 colours (i.e. the abundant secretion of pigment} 

 have caused the inedibility of the species, rather 

 than that the inedibility has necessitated the 

 production of bright colours as an advertisement" 

 In other words, Neo- Darwinians put the cart 

 before the horse ! 



In some cases these brilliantly coloured insects 

 may be survivals of an age in which there were 



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