Identifier: birdlifeguide00chap (find matches)
Title: Bird-life; a guide to the study of our common birds
Year: 1898 (1890s)
Authors: Chapman, Frank M. (Frank Michler), 1864-1945 Seton, Ernest Thompson, 1860-1946
Subjects: Birds -- United States
Publisher: New York, D. Appleton and company
Contributing Library: American Museum of Natural History Library
Digitizing Sponsor: Biodiversity Heritage Library

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which conform to the generallaw of protective coloration. There are, it is true, excep-tions, but every close student of bird-life must be so im-pressed with the dangers to which birds are exposed, thathe can not doubt that the chief object of color is usuallyfor its wearers concealment. The term protective coloration has lately receivedfresh significance through the studies of Mr. Abbott H.Thayer.* Mr. Thayer proves conclusively that protect-ive coloration lies not so much in an animals resem-blance in color to its surroundings as in its gradation ofcolor. Thus he points to the fact that, as a rule, animalsare darker above than below—that is, those parts receiv-ing the most light are darkest, while the parts receiving theleast light are palest. In effect it follows that the darkerupper parts are brightened, while the paler under parts are * See his papers -on The Law which Underlies Protective Colora-tion, in The Auk (New York city), vol. siii, pp. 124-129, 318-320, elevenfigures.
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Plate XII. Pace 101. RUFFED GROUSE. Length, 17-00 inches. Male, neck tufts long, bhxck; upper parts and tail gray or rusty, black and buff; under parts white, black and rusty. Female, similar, but with neck tufts no longer than adjoining feathers. PROTECTIVE COLORATION. 43 darkened, the result being a iniiforni color, with an ap-parent absence of shadow, tending to render the objectinvisible. Mr. Thayer clearly demonstrates his discovery byusing several decoys about the size and shape of a Wood-cocks body. These he places about six inches above theground on wire uprights, or in a row on a horizontal rod.One of these decoys he colors uniformly, above and be-low, to resemble the earth about it, or he may even giveit a fine coating of the earth itself. The upper half ofthe other decoys is treated in exactly the same manner,but their lower half is graded to a pure white on the me-dian line below. At a distance of forty or fifty yardsthe uniformly colored decoy can be plainly seen, butthos

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