Page:Popular Science Monthly Volume 48.djvu/781

Rh considered was, How far is it likely that the individual experiences of parents are transmitted to offspring? In discussing this question Prof. Morgan gave the results of some recent experiments by himself and his students. A chick of a common fowl, hatched in an incubator, was secluded from parental care, and found to be destitute of knowledge that water is good to drink. The little creature would wade in water, and only when it pecked its toes, and so incidentally thrust its bill in the water, did it fill its mouth and turn up its head in the familiar thirst-quenching attitude. Prof. Morgan inferred that it is only by imitating its mother or in imitating another chick that drinking is usually learned. Hence, as a chick is not left to its own ignorance in the matter, natural selection has never had a chance to eliminate birds through their not knowing how to drink. From the fact that the instinct to drink is not transmitted in perfection, Prof. Morgan argues that it is not the inheritance of experience acquired during the individual life, but the natural selection of favorable variations, that determines survival. However, in the case of the megapode of the Philippine Islands, which is hatched in a mound of vegetable matter without parental care, it must be that the chick is born with perfect instinct as to drinking.

Prof. Morgan found his chicks born with an instinct to peck—at no matter what beads, pinheads were as enticing as grain. One experiment or two at most with a nauseous caterpillar proved enough for careful avoidance thereafter. Young bullfinches left to themselves were observed to pull primroses to pieces in an utterly random fashion; but some thirty trials taught them their work perfectly, so that they came as expertly as adult birds at the drop of sweet dew within the flower. Their intelligence did not create a new activity, but selected from a number of indeterminate acts the one act which was both useful and pleasant, the impulse, and the impulse only, being instinctive.

A London bird fancier, in a large way of business, was quoted by Prof. Morgan as finding that young linnets and thrushes brought up among various other birds, nevertheless sang true; young bullfinches, in the same circumstances, imitated their neighbors. A student of Prof. Morgan's secluded a young bullfinch from all opportunity of observing nests: its first nest was true in form, but not true in material, although the usual material could have been chosen by it; its second nest was true in both form and material. A cat taught by Prof. Morgan to retrieve did not transmit the talent to its family. There are on record three cases of dogs and one of a cat which did transmit to their offspring the capacity to "beg."

Prof. Morgan is to continue experiments the prime interest of which is in denoting that natural history has entered upon a new stage. Instead of merely repeating old observations of birds and beasts, instead of gathering their nests, eggs, and skins as thousands have done before, the naturalist, young or old, can easily carry forward experiments intended to throw light on unsettled questions of profound interest. He can observe how a bird varies its song or the building of its nest under circumstances which exclude the possibility of imitation. He can note the degree of domestication, very great in the case of the quail, possible with easily secured specimens of wild birds. He can ascertain whether "begging" or pointing taught a dog, and unknown before