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ANIMAL AND PLANT INTELLIGENCE
HEN I hear a person expatiating on the reasoning powers of the lower animals, as I very often do, I want to tell him of the wonderful reasoning powers of the flies that pester our cow in summer. Those flies have measured the length of the old cow's tail so accurately that they know the precise spot on her body where the tail cannot reach them; on these spots they settle and torment her. Their behavior reveals great powers of calculation and reasoning. By what means they measured the swing of that tail so accurately I do not know. When I come slying up with a switch in my hand, they dart away before I can get in a stroke, because they know I can reach them; they take the measure of my arm and switch on the instant on the fly, as it were. And what shall we say of the mosquito that so quickly finds out the vulnerable parts of one's clothing? If one chances to be wearing low shoes, does she not know at a glance where to strike, though she may never have seen low shoes before?
Now is not that reasoning just as good as much of the reasoning that the public indulges in upon these subjects? Or, take the wit of the old cow herself. Yonder is a very steep hillside, the high, abrupt bank of an old river terrace. Along this bank the cattle have made a series of parallel paths, level as the top of the terrace itself. The paths, I should think, are about four feet apart, just far enough so that the cow walking along one of them can graze at her ease over all the strip of ground that lies between it and the next path. When she comes to the end, she steps up into the path above and repeats the process, and so on till the whole side of the terrace has been grazed over. Does not this show that the cow is very level-headed, that she can meet a difficult problem and solve it as rationally as you or I? Without the paths, how awkward and difficult the grazing would be! Now it is done easily because it is done from level paths; it is done thoroughly because it is done systematically. If you or I were going to search that hillside over daily, should not we adopt similar or identical tactics?
In Idaho I saw that the grazing sheep had terraced the grassy mountain-sides in the same way. Their level paths were visible from afar. How inevitable and free from calculation it all is! The grazing cattle take the easiest way, and this way is horizontally along the face of the hill. To take the
hill by a straight climb or diagonally would be labor, so the animal moves easily along its side, cropping the grass within reach. Then she takes a step or two upward and grazes back the other way, and this process is repeated till a series of level parallel paths are worn in the side of the hill. They are as much a natural result as is the river terrace itself.
The cow has always been a famous engineer in laying out paths; sheep are, too. They take the line of least resistance; they ford the streams at the best places; they cross the mountains in the deep notches; they scale the hills by the easiest grade. Shall we, therefore, credit them with reason?
When I was a bucolic treasury clerk in Washington, the cow of an old Irishwoman near by used to peep through the cracks in my garden fence at my growing corn and cabbage till her mouth watered. Then she saw that a place in the fence yielded to me and let me in, so she tried it; she nudged the gate with her nose until she hit the latch, and the gate swung open by its own weight and let her in. There was an audible crunching of succulent leaves and stalks that soon attracted my attention. I hustled her out, and sent a kick after her that fell short and nearly unjointed my leg. But she was soon back, and she came again and again till I discovered her secret and repaired the latch so that nudging or
butting the gate would not open it. How surely such conduct as this of the cow's evinces reason to most persons! But shall we not rather call it the blind gropings of instinct stimulated into action by the sight and odor of the tender vegetables? Many of the lowest organisms show just as much intelligence about their food as did the old cow. Even the American sundew, according to Mrs. Treat, will move its leaves so that it can seize a fly pinned half an inch from it. The method of the old cow was that of hit and miss, or trial and error. She wanted the corn, and she butted the gate, and as luck would have it, when she hit the latch the gate swung open. But shall we conclude that the beast had any idea of the principle of the gate? Or any idea at all but the sense impression made upon her hunger by the growing vegetables? Animals do not connect cause and effect as we do by thinking the "therefore;" they simply associate one thing with another. Your dog learns to associate your act of taking your hat and cane with a walk, or your gun with the delights of the chase, or with its report, if he is afraid of it, and so on. Without this power of association the birds and beasts, could not get on in life; the continuity of their experience would be broken. It is a rude kind of memory sense memory. A sense impression to-day revives a sense impression of yesterday, or of the day before, and that is about all there is of it.