Page:Popular Science Monthly Volume 30.djvu/627

Rh crocodile, and in return warned it against its enemies, which has been laughed at as fabulous; but, in the light of modern observations, there is nothing incredible in it.

Hunger sometimes causes birds to take to the most unaccustomed foods. When sparrows gather around fresh horse-dung and turn it over with evident relish, it is on account of the undeconiposed oats it contains; but there are real coprophagists or dung-eaters among birds. Some vultures, according to Brehm, live chiefly on human excrement, and one of the handsomest gulls of the far North feeds largely on the droppings of seals and walruses.

There are aberrations of taste among birds as well as among men and other animals, the exact origin of which can be definitely traced out. Tame birds—geese, fowls, and doves, the last of which in particular are strict vegetarians—can, by the "withdrawal of their accustomed grain, be won over to the enjoyment of animal diet till they prefer it, and may finally have their new taste so highly cultivated that they will spurn vegetable food. These changes do not mean much when they are compulsory; but they become very significant when they are wholly voluntary. Our common sparrow has within a few years gained legal, scientific, and even political fame by reason of its change of food-habit; and, amid all the controversy that has raged about its character, it is clear that it has become extremely ravenous and destructive to broods of young song-birds. Yet the sparrow is originally an eater of animal food, living on larvæ, worms, and snails, from which the step is not so very great to the devouring of a little wee, helpless chick; but the perversion of taste which the New Zealand kea (Nester productus) has undergone is of a different character. The nature of its home as well as its organization made it clearly a vegetable feeder, and there was no apparent occasion in its normal state for a bloodthirsty taste or a predatory inclination to arise within it. "With the introduction of sheep-raising in New Zealand the bird's nature seems to have been changed. It learned to feast upon the blood of the slaughtered animals, and, having once tasted blood, it conceived such a relish for it that it was no longer able to satisfy its appetite with the occasional slaughter of a sheep, but began itself to take the initiative by falling upon animals which were suffering from slight wounds and opening the sores to make the blood flow. From this it advanced till it learned to help on the accident and make wounds for itself.

Birds living naturally on flesh are sometimes turned, without any stress of necessity, to become vegetarians. A considerable number of insect-feeders in Southern Europe eat fruits, especially figs, with evident relish, and the habit abides with them not only there, but also in other regions when they pass through them. I once became very indignant in Corfu at seeing an old, lank fellow, with a fowling-piece likewise old and lank, shooting the little singing-birds, among which