THE USES OF COLOUR 21 



4. Warning colours 



When an animal possesses an unpleasant attribute, 

 it is often to its advantage to advertise the fact as 

 publicly as possible. In this way it escapes a great 

 deal of experimental ' tasting.' The conspicuous 

 patterns and strongly contrasted colours which serve 

 as the signal of danger or inedibility are known as 

 Warning Colours. In other cases such colours or 

 markings enable individuals of the same species easily 

 to follow those in front to a place of safety, or assist 

 them in keeping together when safety depends upon 

 numbers. 



It is these Warning Colours which are nearly 

 always the objects of Protective Mimicry, and it will 

 therefore be convenient to describe the former before 

 the latter. 



5. Colours produced by Courtship 



Finally, in the highest animals, the vertebrata and 

 many of the most specialised invertebrate groups, we 

 have some evidence for the existence of an aesthetic 

 sense. Darwin believed that this sense was brought 

 into play in courtship, and that colours and patterns 

 have been gradually modified by the preference of the 

 females for the most beautiful males ; he believed that 

 such Sexual Selection accounts for many of the most 

 beautiful features possessed by animals, viz. those 

 which are especially displayed during courtship. 



