Page:Popular Science Monthly Volume 75.djvu/554

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550
THE POPULAR SCIENCE MONTHLY

AN ARRAIGNMENT OF THE THEORIES OF MIMICRY AND WARNING COLORS

By ABBOTT H. THAYER

There is every reason to believe that all animals' eyes see upon one principle, an eye being a machine for receiving what we call light vibrations, so that to receive from any object more of these vibrations is to have it look lighter, and to receive from it less of them is to have it look darker.

IN the last few years, naturalists have received from outside their ranks, the first scientific analysis of the use of animal's colors that has ever been made.

They have been shown the effacing power of the universal counter-shading in animals' costumes, and later, they have seen with their own eyes the equally perfect effacing power of the patterns which up to that moment they had believed to be factors of conspicuousness.[1] They have thus been forced to perceive that all their own theories prove to have been built in ignorance. These were made before the world had perceived the universal importance of employing specialists, and even Darwin and Wallace failed to realize that in view of nature's infinity, one study like their own was all that they could hope to be faithful to. The laws of visibility reach, like all others, into infinity, and could not constitute part of the zoologist's field, while in the science of the painter, these laws are the very pith of his study.

The following demonstration of the fallacy of the badge and warning-color theories is not, in the same sense, an attack upon mimicry, although it inevitably calls attention to the fact that the latter can not survive the demise of these other theories. It does not imply that there is no case possible of protective resemblance of one animal by another, but contents itself with bringing forward conclusive evidence that the great mass of what is now called mimicry is nothing of the kind, but is, in every respect, the same common concealing coloration everywhere to be found where there are common habits and environment. This fact escaped naturalists, simply because it lay out of their special field, i. e., in optics rather than in zoology, and once off the track, they have been driven step by step into the erection of a wholly fictitious fabric, where no fabric at all was required.

  1. I have shown, both to the naturalists at Woods Hole, Mass., and in London, the wonderful concealing power of various representative "conspicuous" costumes, from white patterned birds seen against the sky, to the bright red-black-and-yellow coral snake, supposed to be one of the most conspicuous animals in nature.