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 secretzon of pigment) 
have caused the inedzbelty of the specres, rather 
than that the wnedibehty 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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