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A BI-MONTHLY MAGAZINE 

 DEVOTED TO THE STUDY AND PROTECTION OF BIRDS 



Official Organ of the Audubon Societies 



Vol. Ill November — December, 1901 No. 6 



Recognition Marks of Birds 



BY ERNEST SETON-THOMPSON 



Illustrated by the Author 



IN general the markings of animals are believed to be either protective 

 or directive; that is, designed either to hide the animal, or else 

 to distinguish it and make it conspicuous or ornamental. 



In the bird world we have man}- illustrations of both kinds of colora- 

 tion in the same individual, for man^' species are protectively colored while 

 sitting and directively while flying. Or, to put it in . another way, the 

 colors of the upper parts show chiefly when the bird is perching, and 

 these are protective; the colors of the lower parts and expanded wings 

 are directive, and are seen chiefly in flying. All birds with ample wings 

 and habits of displaying them, bear on them distinctive markings; for 

 example: Hawks, Owls, Plovers, Gulls, etc. All bird students will recall 

 the pretty way in which most of the Plovers let the world know who 

 they are. As soon as they alight, they stand for a moment with both 

 wings raised straight up to display the beautiful pattern on the wing 

 linings; a pattern that is quite different in each kind and that is like 

 the national flag of the species, for it lets friend and foe alike know 

 what species is displaying it. 



On the other hand, birds like the Hummingbird, whose wings move 

 too rapidly for observation, are without color pattern on the under side. 

 These markings, no matter which category they belong to, are put on 

 the bird first of all to be of service to its own kind. That is certain, 

 as certain as the main truth of evolution ; for, as Darwin long ago 

 stated, if it can be shown that any species has acquired anything that 

 is of use only to some other species, then the theory of evolution by 

 natural selection must fall to the ground. 



But this does not say that an acquired characteristic may not also be 

 of use to another species. Thus the directive and recognition marks of 

 the Hawks and Owls as illustrated on my plate are, of course, first to 



