The vigorous avocations of the chase and war were reflected in fine stature, broad and deep chests, strong and clean limbs, and sound constitution among the Siouan tribesmen and their consorts. The skin was of the usual coppery cast characteristic of the native American; the teeth were strong, indicating and befitting a largely carnivorous diet, little worn by sandy foods, and seldom mutilated; the hands and feet were commonly large and sinewy. The Siouan Indians were among those who impressed white pioneers by the parallel placing of the feet; for, as among other walkers and runners, who rest sitting and lying, the feet assumed the pedestrian attitude of approximate parallelism rather than the standing attitude of divergence forward. The hair was luxuriant, stiff, straight, and more uniformly jet black than that of the southerly stocks; it was worn long by the women and most of the men, though partly clipped or shaved in some tribes by the warriors as well as the worthless dandies, who, according to Catlin, spent more time over their toilets than ever did the grande dame of Paris. The women were beardless and the men more or less nearly so; commonly the men plucked out by the roots the scanty hair springing on their faces, as did both sexes that on other parts of the body. The crania were seldom deformed artificially save through cradle accident, and while varying considerably in capacity and in the ratio of length to width were usually mesocephalic. The facial features were strong, yet in no way distinctly unlike those found among neighboring peoples.
Since the advent of white men the characteristics of the Siouan Indians, like those of other tribes, have been somewhat modified, partly through infusion of Caucasian blood but chiefly through acculturation. With the abandonment of hunting and war and the tardy adoption of a slothful, semidependent agriculture, the frame has lost something of its stalwart vigor; with the adaptation of the white man’s costume and the incomplete assimilation of his hygiene, various weaknesses and disorders have been developed; and through imitation the erstwhile luxuriant hair is cropped, and the beard, made scanty through generations of extirpation, is commonly cultivated. Although the accultural condition of the Siouan survivors ranges from the essentially primitive status of the Asiniboin to the practical civilization of the representatives of several tribes, it is fair to consider the stock in a state of transition from barbarism to civilization; and many of the tribesmen are losing the characteristics of activity and somatic development normal to primitive life, while they have not yet assimilated the activities and acquired the somatic characteristics normal to peaceful sedentary life.
Briefly, certain somatic features of the Siouan Indians, past and present, may be traced to their causes in custom and exercise of function; yet by far the greater number of the features are common to the American people or to all mankind, and are of ill-understood significance. The few features of known cause indicate that special somatic characteristics are determined largely or wholly by industrial and other arts, which are primarily shaped by environment.