Page:Popular Science Monthly Volume 79.djvu/24

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20
THE POPULAR SCIENCE MONTHLY

CONCEALING COLORATION[1]
By ABBOTT H. THAYER
MONADNOCK, N. H.

At the last meeting of the American Ornithologists' Union, in Washington, some forty naturalists looked in broad daylight straight at a small stuffed deer that wore from its dorsal line down its sides two white stripes in imitation of those of certain African antelopes. These stripes were in every respect such as Theodore Roosevelt says have no concealing virtue of any kind whatsoever.[2] Yet they so completely concealed this deer in an almost clean-shorn public park that although for each of the forty spectators I pointed straight at the deer only ten yards away, not one of them detected it. The animal was placed just above the eye-level of the spectator, exactly as African antelopes would be above that of the creeping lions or leopards. And, exactly as would commonly be the case with the antelopes, the white stripes absolutely counterfeited the glimpses of the sky-background seen through the thin half leafless bush that intervened. When the white stripes were removed the spectators exclaimed at how clearly one

  1. These wholly unretouched illustrations absolutely demonstrate the wonderful concealing effect of the white patterns that Roosevelt and others say have no concealing effect whatsoever. These play, as Roosevelt truly asserts, little or no part when the wearer is out on the safe open plain, but seem designed for making him the very worst of targets when he tries to dodge the spring of an ambushed lion or leopard, especially at night, just as the night hawk's colors, dark and conspicuous to terrestrial eyes through all his safe aerial hunting, prove to be an unmistakable picture of his background when at last he squats on the bare rock in danger from predatory birds and mammals. No one can study these oryx head pictures without perceiving that, against the ground, the brown (of course countershaded) head is hard to distinguish, while the black and-white one is very conspicuous. On the other hand, when the same two heads are looked at from below, i. e., against the sky, it is the brown one that shows, and the brilliant black-and-white one that is now hard to detect. It is of this black-and-white oryx head that Roosevelt writes: "A curious instance of the lengths to which some protective-coloration theorists go is afforded by the fact that they actually treat these bold markings as obliterative or protective." Colonel Roosevelt, like the rest of the world, seems never to have thought to find out how these patterns look from a lower level, such as lions and leopards necessarily see from, they being under three feet tall, while the oryx and zebra are nearer five. This great oversight invalidates almost all that has ever been written on this subject.
  2. "African Game Trails," Appendix E.