Page:Popular Science Monthly Volume 9.djvu/368

346 imitation of the movements of the parents when in search of food; judgment as to localities, on the part of the young, and allied circumstances connected with procuring food, come by experience. Watch a restless little creeper, during these chill winter mornings (Certhia familiaris), as it flies from tree to tree, and clambers over and about the rough bark. It seems, indeed, a mere automaton, driven, and not going of its own free-will; but, if we continue our observations but a little longer, we shall find it really a discriminating creature, passing by certain trees that are to us all one with those visited. It is not chance, but a consciousness of the uselessness of search, that determines its flight to some more distant rather than a nearer tree.

As an example of the knowledge gained by young birds through imitation, let us take young woodpeckers. On leaving the nest, they accompany their parents, but are not fed by them. Like the old birds, they immediately commence to climb the trunks and branches of the trees. Having been fed with insects when in the nest, they are already able to recognize their proper food, and devour the visible insects they may discover on the outer surface of the bark. Now, was it the example set by their parents, or the peculiar construction of their bill and feet, that was the cause of their having sought the trees, and climbed over them in the peculiar manner common to their kind? I think, clearly the former. Now, merely clambering over the bark of trees would not enable them to secure sufficient food, and imitation could not extend beyond this point; but here experience comes into play, and the gradual acquirement of the whole routine is easily traced. The bark of trees is nearly always cracked, and in the crevices are more insects than on the surface, and the habit, soon acquired, of search in the cracks of the bark is the one step from searching over the exposed surface to search beneath. Imitation led the ignorant young bird to the thrifty growth of timber, and not the tangled hedge-rows. Experience taught him the accustomed haunts of those insects on which Nature bids him prey. If we go back into the remote past, and recall the ancestral woodpecker, we can with no undue use of the imagination picture to ourselves the first steps that led the good climber to find in the half-decayed bark the nourishing food abounding there; and now let us return to the present, and seek for some variation in the habits of the birds of today. As an instance, the "flicker," or golden-winged woodpecker, leaves the timber-lands, and in loose flocks, often in company with robins, wanders over pasture-fields and meadows in search of food, more especially the crickets, and not under fences do they look for them, but under the dry droppings of the cattle. Here is an instance where accident, it may be, gave origin to, and experience has confirmed into a habit, a decided variation from normal woodpecker life. Now, a young woodpecker leaving its nest June 1st, if dissociated from its kind, would never leave the woodlands, and, seeking the