Page:Popular Science Monthly Volume 41.djvu/511

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495
THE PREHENSILE FOOT OF EAST INDIANS.

upon it an argument against the application of the transformist theory to man. Some Darwinians believe that if man used his foot constantly and generally as a prehensile organ, an opposition of the great toe would be gradually evolved in the adaptation of the organ to that function. The preceding study, however, proves that this is not the fact. Among a people who have for centuries commonly used their feet as a prehensile organ no movement of opposition has been produced; while in some persons an adaptation to the new function has been observed, namely, a separation of the great toe and wide and strong lateral movements, but only lateral—a pincers-foot, not a hand-foot. It will be seen, on reflection, that the condition could not be otherwise.

In walking, the weight of the body is borne on the heads of the five metatarsi, but mostly on the head of the first one. If that was not united solidly to the second metatarsus, and could turn around it as is done in the hand, it would give way every time the foot touched the ground, and the foot would want a sufficient internal point of support; walking would still be possible, but it would be hard and laborious—occasional, and not a habitual normal act. It is thus with the monkey, which is supported solely on the outer edge of the foot. Even the anthropoid walks rarely and awkwardly; its foot, adapted to living in the woods, has the opposition movement convenient for climbing easily; it has a foot-hand. The man who, continuing to walk, likewise wants a prehensile foot, can not enjoy this movement, which is incompatible with walking. He satisfies himself with lateral movements between the great toe and the second toe, or a pincers-foot. All this is simply a consequence of the general biological law of the adaptation of the organ to the function.—Translated for The Popular Science Monthly from the Revue Scientifique.

 


 
A curious, secretive proceeding of swans is described in Nature by Jessie Godwin-Austen. The cygnets having been just hatched out, the male bird picked up an empty half egg-shell lying beside the water and carefully carried it to the edge of the water some twenty feet from the nest, filled it with mud, and pushed it into the river, where it sank to the bottom; and then repeated the performance with the other half egg-shell. On returning to the nest the last time, he placed a few sticks across the small track he had made. As no other pieces were seen about the nest, while five cygnets were hatched, it is inferred that the bird had done the same with all the egg-shells.

A paper by Mr. Edward Dobson, in the Australasian Association, on Human Habitations in Prehistoric Times, was devoted to showing that, while rectangular forms prevailed in the early buildings of the East and in North America, the circular form had prevailed throughout Africa (with the exception of the Nile Valley) and through Switzerland and northern Europe, in Lapland and Greenland; and raised an inquiry as to the causes of these facts.