146 STUDIES IN THE EVOLUTION OF ANIMALS 



similar contrasts. The peculiarity of its contrasted coloration, the 

 writer says, is regarded as belonging to the class of so-called 

 * warning colours.' Mr. Poulton observes that such warning colours 

 would seem ' to benefit the would-be enemies rather than the con- 

 spicuous forms themselves But the conspicuous animal is 



greatly benefited by its warning colours. If it resembled its 

 surroundings, like the members of the other class, it would be 

 liable to a great deal of accidental or experimental tasting, and 

 there would be nothing about it to impress the memory of an 

 enemy, and thus to prevent the continual destruction of individuals. 

 The object of warning colours is to assist the education of enemies, 

 enabling them to easily learn and remember the animals which are 

 to be avoided.' 



There cannot be much doubt that an animal possessed of such 

 a coloration and character, and also of such ' nauseous and irritat- 

 ing artillery/ as has been described, would be avoided, when its 

 means of defence had become known. But we cannot in any way 

 admit that it is its * stinking secretion ' which has caused this ' con- 

 trast of coloration.' The animal itself no doubt has learnt that it 

 is not attacked, and this accounts for its ' indifference to the pres- 

 ence of other creatures ' which is said to be ( one of the most striking 

 characteristics of this animal and its congeners.' Therefore the 

 contrast of coloration between the white upper surface and crown, 

 and the black under surface and face, must be attributable to some 

 other cause. 



When the plan of coloration of this White-backed Skunk became 

 once established by hereditary influences, it began to change like 

 everything else, unless it were maintained by natural selection, 

 through the action of the surroundings, as has happened in the 

 case of the Leopards ; and this change we see, further on, in a 

 brother Skunk. 



