Eastern United States is embraced in the eastern maize area. Beginning at the Colorado River and extending down through the Isthmus and the Andean regions to the lower part of Chile, is the area of intensive agriculture in which maize is also the leading food. The interior of the southern continent, centering around the Amazon drainage, is, in the main, a dense tropical forest about whose native inhabitants we have the least knowledge of any. In fact, we cannot certainly characterize the food of the whole area, but inferring the whole from the known parts, we should say that small game and cultivated manioc are the important foods. Finally, the lower part of the continent has certain similarities to the North American caribou area, the chief food animal being the guanaco.
It will be observed that these eight areas can be grouped: three of them being the homes of hunting peoples, three of agriculturists, one of fishers, and one of gatherers of wild seeds.
In the caribou area live two groups of tribes generally recognized as having little in common, the Eskimo and the Canadian Indians. As we shall see later, this view as to their diversity is in a large measure justifiable, but with respect to food they have close similarities. It is customary to characterize the Eskimo as a people living upon sea mammals, particularly the seal; but we must not overlook the fact that their winter clothing is of caribou skin and that the flesh of that animal is an important part of their diet. However, the severe winters of their extreme northern range drive the caribou southward and leave the seal the only recourse during the period of prolonged darkness. Yet whenever the caribou are in reach the Eskimo places his chief dependence upon them. Thus, while our classification should not be permitted to obscure the large part that sea mammals play in the domestic economy of the Eskimo, the caribou is absolutely indispensable to his existence, not so much for food as for winter clothing. Hence, we see that Eskimo culture must be considered as a modified form of caribou culture.