SOME EXPERIMENTS ON PROTECTIVE 

 COLORATION 



R. T. YOUNG 



University of North Dakota 



EIGHT TEXT FIGURES AND THREE PLATES 



The theory of protective and aggressive coloration, assuming 

 as it does, the use of such color in protecting its possessors from 

 their enemies, or enabling them to steal unnoticed on their 

 prey, has, as yet, insufficient experimental evidence for its foun- 

 dation, being based largely upon human experiences of taste, 

 sight, and smell, which are by no means a fair criterion of simi- 

 lar senses in lower animals. 



Beddard ('92) in his work on Animal Coloration says, page 

 156: 



The instance shows the pitfalls which surround the path of those 

 who wish to deduce theories from experiments of this kind, which are 

 necessarily made in verj^ great ignorance of bird psychology, or even 

 physiology. 



On page 166 of the same book he says: 



These experiments certainly bring out the fact that the likes and 

 dislikes of insect-eating animals are purely relative. They are further 

 proof of the old saying that one man's meat is another man's poison. 

 . . . . But none of these experiments are thoroughly satisfactory. 

 It is difficult to interpret them and they are often contradictory, for 

 a bird will eat one day what it has refused before. 



Again on page 196 he says: 



It is not reasonable to lay much stress upon the fact of insects possess- 

 ing qualities which are disagreeable to ourselves, for it by no means 

 follows that these same qualities affect the enemies of the insects. In- 

 deed, there is experimental evidence that the reverse is the case. 



There are numerous other difficulties in experiments of this 

 sort, first among which is the fact that they have mostly been 



457 



THE JOURNAL OF EXPERIMENTAL ZOOLOGY, VOL. 20, NO. 4 

 MAY, 1916 



