Abbott H. Thayer

“ All woodsmen know that when one has followed with the eye some bird or arboreal beast, and lost it in the trees, the eye searches every mass of foliage silhouetted against the sky, scarcely counting on discerning the creature's outline, so much as on noting some mass of unbroken dark—dark without any sky-hole through it—sufficiently extensive to contain the animal itself. ”

“ In fine, we find upon certain species of carnivora that we know to be more or less scavengers and catchers of small fry such as require rather to be picked up than stalked or chased, and on others that we suspect of having the same habit, the same sky-picturing patterns that, from the eye-level of their prey, efface the top contours of most other slow walking feeders-on-small-life, in all branches of the animal kingdom. ”

“ The thousands of species of open ocean fish, the bare sand-dwellers and the ocean-air-fliers, all wear only the colors that characterize their backgrounds, often adding for the breeding season bits of the scenery of their nesting place, as in the case of puffins, whose gaudy breeding-season-bill on guard at the mouth of the burrow, obliterates the dark hole itself, and at the same time substitutes a semblance of flowers to complete the deception. ”

“ At the left a butterfly of the same costume is represented passing through a moment of illumination too great to admit of its patterns' still cutting it apart into notes of the background. At the right a butterfly of the same pattern Is going through the reverse experience, being for an instant too much in shadow for its pattern to save It from appearing as one single dark form against the light space beyond. This illustration reminds one how perpetually such vicissitudes must succeed each other in the life of such species. ”

“ We find that the whole subject of animals' coloration has been handled with very loose thinking, as if the old time disrespect of natural history still haunted men's minds and dissuaded them from real study. ”

“ It is certainly the universal experience of American country dwellers that although in their domestic duties they must frequently pass within a few feet of skunks, yet the whole family together scarcely see one a year. Under shrubbery, moonlight, which might be expected to reveal these animals, adds, on the contrary, to the scene hundreds of white patterns, and these often all in motion, so that what was before a comparatively negative form of concealment becomes a most brilliant and positive illusion. ”

“ There seldom pass many minutes without some breeze to set in motion the many more or less white details of the shrubbery, so that the disembodied light patch of this little hunter's coat may move, even within the short visibility-range that we have discovered it to possess, yet by no means commonly attract our attention. ”

“ But their habits preclude the possibility of this, their own changes of position, not to speak of those of the spectator, bringing them, as they fly about, across, often in a single second, the whole gamut of backgrounds, from brightest sky to deepest tree-shadow, and back. And against every one, except the single one which they match, they are clearly visible. ”

“ But a very different fate attends the life of aerial species destined constantly to appear against more or less distant backgrounds which do not share their particular momentary illumination, and which constantly show, now light, when the flying bird or butterfly is dark, and the next instant dark when he is light. ”

“ Perhaps the most highly artificial and strained hypothesis that has been released from duty by the discovery of the use of patterns is the conception that after a million years' experience birds would not inevitably know what part of a butterfly is edible and instinctively seek it, rather than try to eat the tissue-paper pictures of background painted along its wing-borders. ”

“ The skunk, by the way, varies in appearance far more than the mink, ranging from nearly all black to half white, and this is another evidence that his pattern is not for identification. Naturalists' assertion that patterns serve equally both purposes is like two men claiming the same dog. The wise judge puts it to the test as to which man the dog will obey against the commands of the other. If we call animals' costumes the dog, we find that he always obeys Master Concealment, but obeys Master Warning-color only when Master Concealment has commanded the same thing. ”

“ The following pages demonstrate that all diversification of the colors of animals' costumes tends wholly and unmixedly to conceal them. This should set the believers in conspicuous species reflecting that while they are making their records of cases of momentary conspicuousness of individuals of one species or another, they are making no investigation whatever of the possibility that all the while a large number of individuals of this same species are, through some magic of their costume, escaping their sight and making no impression on their minds. ”

“ In Trinidad, one of the keenest of that remarkable able family of born naturalists, the Carrs, told me that he had never seen a bird catch a butterfly, and this has almost or quite been my experience too. In Trinidad, for instance, one may see flycatchers catching slow fliers like beetles, by the hour, any day, but never see them pay the slightest attention to any butterfly whatever. ”

“ The principle of pattern arrangement in these famous "mimetic" groups (shown in Fig. 6) is out and away the predominant one over the whole globe. If this is the case, is it strange that in each most swarmingly populated seat of butterfly life there prove to be a number of species which, living in the very same station, and with seemingly identical habits, have, in obedience to this great pattern-law, practically identical patterns and form? We see in the ocean, for instance, even mammals wearing the shape and color of fishes? ”

“ It is not yet generally perceived that in the scenery about us every spot means to a casual observer one thing, and it follows that two different color-patches, as of the skunk, amidst the million color-patches in sight, tend, especially when more or less eclipsed by vegetation, to mean, not one pied animal, but two different elements of the scene. ”

“ Our identification of familiar objects depends, fundamentally, upon unvaryingness of their appearance. We know the mink just as well by his slim form and sleek dark monochrome as the skunk by his fatter form and bushy black and white. ”

“ He lives in cover, the very kind of cover to which small birds fly from a hawk, and through this he sails and flits in the only conceivable manner, threading its minute alleys with short wing beats, and at times almost seeming to stop and crawl through the narrowest places. ”

“ These two climaxes of visibility, first one and then the other, occur in the flight of a bird or butterfly often at the rate of several a second, while, during the rest of the second, the creature is effaced by passing a background that his costume matches, and by being, as in the case of the butterflies A and B, midway between the extremes, favored by the momentary illumination's being neither too great nor too small. Even in the climaxes of conspicuousness his patterns still perpetually lessen his visibility in direct ratio to their strength. ”

“ Not till naturalists give up collecting records of cases of conspicuousness, and begin to inquire by experiment whether any more procryptic coloration could, under the animal's circumstances, be devised, will they have begun at all the study of this subject. One day's investigation of this kind would greatly astonish them, and they would end by discovering that it is unequivocally the wasp's actions that condemn it to so much visibility, and this in spite of its wearing, as far as they can discover, every available form of concealment-coloration. ”

“ In pursuit of food, or in storing it, they all either go bodily into holes, as bees and wasps into flowers and fruit cavities, or ants into their galleries, and as do the weasel family after burrowing mammals, or like the grubbing species above mentioned, and foxes, stick their heads into holes for similar purposes. In all these cases these rear-armed species have a common need to be so armed, being totally helpless to defend themselves while thus immersed. Of all animal adaptations this stink apparatus was the thing most to be expected in a part of the animal so entirely defenseless. ”

“ Lifelong members of a community, all reacting upon each other in a hundred ways, know each other by innumerable means, all communicating with their subliminal consciousness. To this consciousness, the movements, for instance, of a mink in the bushes, probably announce his identity to all his neighbors, who hear him, just as plainly as if they saw him, and the least glimpse of him would, upon the same principle, be as good as a full view. ”

“ Gadow, who believes that it is shadows flickering over a lizard's back that cause his patterns, ignores the unmistakable fact that lizards, like all other terrestrial species, are colored and patterned to match the ground on which they live, no matter whether there be vegetation over head to cast shadows, or, as on sea-beaches and bare rocks, nothing but air and sunlight. The humidity theory has the same defect. ”

“ In fine to imagine that the forest population, living side by side, in perpetual need of knowing each other, would be in any way helped by badges, is as if some person, newly arrived in a long-established community, supposed, because he could only distinguish its members by prominent superficial marks, the red hair of one, the pock marks of another, etc., that this was how the members themselves knew each other, after lifelong familiarity. ”

“ Those hares and antelopes and deer which, by virtue of a white sky-imitation on their rears, were not too fatally good a target against the night sky for the stalking feline that flushed them, have survived to propagate their race. ”

“ One advantage which patterns do certainly sacrifice in purchasing the above advantages is that, although their Wearer is never seen entire until the background is too dark for his black, or too light for his white, yet it is true that, on the other hand, some note of a pied costume is always to be detected moving when the wearer moves. ”

“ This wonderful universal function of top-white will only begin to have vitality in the minds of students of natural history, when they begin to take the trouble to spend hours, lying flat on the ground, studying terrestrial life from the true point of view. ”

“ Let us dwell a moment upon the significance of this finding of the greatest cryptic coloration in the very midst of the so-called mimetics. First we must remember that all men agree that it is only persecution that can have engendered any form at all of protection. It is, as I have said, inconceivable that any forever preyed-on and picked-from race should not have acquired all possible unpalatability. ”

“ The much insisted upon significance of the superficiality of the resemblances among the "mimetic" groups vanishes upon our discovery of a full blown use, of the most direct and primitive character, for all these colorations. From that moment, these resemblant costumes are seen to be, as I have pointed out, on one basis with the many other resemblances among species of widely different origin that have long enough had the same habits and environment. ”

“ Now let us see whether such stench-gland bearers as hunt in a bolder way wear the white "badges." We find at once that minks, martens and most weasels, though well-armed with the same glands, have no top white, and, instead of hunting along the earth's surface or putting merely their heads into holes for their prey, go boldly under ground and attack such prey as hares and marmots, or fasten upon fowls much larger than they themselves. ”