THE BASIC PRINCIPLES OF PROTEC- 

 TIVE COLOURATION IN THE ANIMAL 

 KINGDOM 



By MRS. ARTHUR BELL 



Lovers of art on both sides of the Atlantic have long been 

 familiar with the name of Abbott Thayer, whose fine paintings 

 have won him a very high position amongst his contemporaries. 

 But comparatively few, especially in England, know him as 

 the distinguished naturalist who, in the course of many years' 

 close observation in the forests surrounding his New Hampshire 

 home, has discovered what he considers is the basic principle 

 of protective colouration in the animal kingdom. 



Speculation on this subject has till recently proceeded on 

 four great assumptions. These are : the principle of the Sur- 

 vival of the Fittest or Natural Selection, the principle of Sexual 

 Selection, the principle of Protection by means of Mimicry and 

 the principle of Protection by means of Concealment. That is 

 to say, it has been taken as proved that different colours 

 and hues have been developed in animals by two main pro- 

 cesses, for two main purposes. The first process is the survival 

 of those most able, thanks to peculiarities of colouration, to 

 conceal or disguise themselves, either from their enemies or 

 from their victims and the consequent transmission of these 

 peculiarities to their offspring. Over against this process, how- 

 ever, the followers of Darwin have assumed that another great 

 force was at work, a force making not for but against pro- 

 tective colouration : this is the tendency of females to choose 

 their mates from among the more brilliantly coloured or marked 

 males who compete for them and thus to favour the trans- 

 mission to succeeding generations of peculiarities selected not 

 because they increase the safety but rather the conspicuousness of 

 their possessor. Hence the existence of highly coloured species 

 is accounted for despite the fact that brilliance of colour has 

 been assumed to be the very reverse of a protection to its 

 wearer. So much for the processes by which colouration is 

 developed The purposes which protective colouration serves 



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