COLORATION 97 



birds it may affect a slightly larger proportion of species, 

 but the number remains but an insignificant fraction of 

 the whole. In the great majority of species both of birds 

 and of mammals countershading is certainly not a factor 

 of survival value, such as could in any way affect or be 

 affected by natural selection. Even in the comparatively 

 few remaining cases, where it is possible that it has a small 

 effect of solid value in concealing the species, it is very 

 doubtful if it has been produced by natural selection, or in 

 any other way, because of its concealing value; it seems far 

 more probable that it is produced by some such cause as 

 that which makes the under side of most leaves lighter than 

 the upper, and that its trivial influence in increasing the 

 concealing value of the coloration in these few species rep- 

 resents nothing but an accident. 



One reason why the study of the coloration of big game 

 is of prime scientific importance is that it enables us to 

 visualize to ourselves something of the effect which the 

 coloration of small animals has on their prey or their ene- 

 mies. Nobody in his senses regards a cock ostrich as con- 

 cealingly colored; yet it is exactly as concealingly colored 

 as a cock bobolink, or tanager, or magpie, or lark-bunting, 

 or yellow-headed blackbird, or red-winged blackbird, or 

 cow-bunting, or purple grackle, or oyster-catcher, or black 

 and white spur-winged plover, or European blackbird, or 

 black and white chat. An ostrich looms to our eyes pre- 

 cisely as a coot does to the eyes of a mink or a prairie-hen 

 to the eyes of a black- throated ferret; an ordinary antelope 

 appears to the eyes of a hunter from the same angle that 

 a deer appears to a cougar, or a zebra or buffalo to a lion. 



Another thing always to keep in mind is that in nature 



