Page:Popular Science Monthly Volume 17.djvu/267

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THE RATE OF ANIMAL DEVELOPMENT.
255

"Physicus. I think I have observed that birds learn to fly and acquire the use of their wings by continued efforts in the same manner as a child does that of his limbs.

"Ornither. I can not agree with you. Young birds can not fly as soon as they are hatched, because they have no wing-feathers; but, as soon as these are developed, and even before they are perfectly strong, they use their wings, fly, and quit the nest without any education from their parents."[1]

Very similar assertions are found in a laborious attempt made by the late Professor Whewell[2] to set aside the palpable fact that man, like every other animal, has an instinctive—or we might perhaps better say an hereditary—knowledge of the functions of his voluntary organs.

Said the Professor: "The child learns to distinguish forms and positions by a repeated and incessant use of his hands and eyes; he learns to walk, to run, and to leap by slow and laborious degrees; he distinguishes one man from another and one animal from another only after repeated mistakes. Nor can we conceive this to be otherwise. How should the child know at once what muscles he is to exert that he may stand and not fall, till he has often tried? How should he learn to direct his attention to the differences of different faces and persons till he is roused by some memory, or hope which implies memory? It seems to me as if the sensations could not, without considerable practice, be rightly referred to ideas of space, force, resemblance, and the like. Yet that which thus appears impossible is, in fact, done by animals. The lamb, almost immediately after its birth, follows its mother, accommodating the action of its muscles to the form of the ground. The chick just emerged from the shell picks up a minute insect, directing its beak with the greatest accuracy. Even the human infant seeks the breast and exerts its muscles in sucking almost as soon as it is born."

So, after all, "that which thus appears impossible" is, in fact, done not by "animals" only, but by man also! The concession contained in the last sentence is simply fatal to what has gone before. To be consistent the learned Professor ought by all means to have asserted that an infant learns to suck only "by slow and laborious degrees," and after its sensations have been rightly referred to appropriate "ideas." It would scarcely be a more unwarrantable assumption than those he has indulged in abundantly in the course of his argument.

In the same vein as Davy and Whewell, teleologists and natural theologians, when enlarging upon the marvels of instinct, have seldom failed to "trot out" the colt, the calf, or the lamb, to invite our consideration to the chickens and the "young ducks," and to erect upon the precocity of these creatures—as compared with the tedious devel-

  1. Collected "Works," vol. ix. "Salmonia," p. 105.
  2. "Philosophy of the Inductive Sciences," ii., p. 616.