Page:Popular Science Monthly Volume 72.djvu/273

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HE purpose of education among those animals that train their young is adaptation to environment. Man's endeavor is the same, but with the growth of human society and of knowledge his environment has profoundly altered, a fact that education has only partially recognized, and this alteration has made it necessary to reinterpret adaptation. Among the lower animals, nature secures the necessary results mainly through instinct.

Jennings found that paramecia collect around a mass of bacteria, pushing and crowding one another in apparent effort to reach the food, and Binet, in one of those delightful, imaginative flights in which even the scientific mind at times is wont to recreate, would have us believe that most, if not all of the higher intellectual processes, including choice and volition, form part of the mental life of micro-organisms. But we are clearly drawing inferences beyond our right if we assume that action here has any other cause than the necessity which selection has made the conditions of survival. These organisms must do certain things and do them always, under penalty of extinction, and perhaps this is the reason why these same paramecia begin to gather around innutritious substances quite as surely as around nutritious. The attraction which a dilute solution of carbon dioxide has for them would then, as Jennings has suggested, be due to the fact that this product of organic waste is found wherever paramecia assemble; therefore, as they gather more often than otherwise around food and natural selection demands that they lose no chance of finding nutriment, carbon dioxide becomes a blind call to food. Instinct is thus organic behavior originating in the necessity of adaptation and directed in its course through the exigencies of the environment by natural selection. Whitman has observed that our fresh-water salamander, Necturus, reacts to any object quietly introduced into the water, as though it were food. If so small an object as a needle, he says, be brought into contact with the surface of the water, Necturus instantly turns toward it. The reason is that the animal receives exactly the same stimuli from a foreign object that touches or passes through the water as it does from