11. Colombia or Chibcha: western Colombia with the nearer parts of Central America and northwestern Ecuador. This is in the main a timbered region.
12. Andean or Peruvian: from southern Ecuador to northern Chile and northwestern Argentina. This is distinctively an arid to sub-arid and unforested belt.
13. Patagonia: characteristically an open, semi-arid country.
14. Tropical Forest: the vast Orinoco, Amazon, and La Plata drainages, prevailingly lowland, humid, and containing the greatest forest in the world. Three sub-regions stand out with a certain ethnic differentiation, although the basis of their culture seems to be that of the woodland. They are: the savannahs of the Guiana region; the highlands of eastern Brazil; the Chaco, west of the middle La Plata system. All three of these are open areas or only part timbered.
15. Antillean: the West Indies, including probably the Venezuela coast. This culture was the earliest to perish in the New World. It received the first shock of Caucasian discovery and settlement, and its carriers had no hinterland to which to retreat. It is therefore imperfectly known. Its closest affiliations are with the preceding area. In fact, the Antillean may yet prove only a subdivision of the Tropical Forest culture. In the discussions that follow, it has been omitted, but can in the main be understood as included in what is said of the Tropical Forest area.
175. Diagrammatic Representation of Accumulation and Diffusion of Culture Traits
The outstanding facts regarding these fourteen or fifteen culture-areas can be most vividly presented in a table allotting a column to each area. Roughly, at least, these columns can follow one another in geographical order. In each column, then, there might be entered all the culture traits found in its area. If one culture were twice as rich or complex as another, the double number of entries would pile up twice as high and impress the eye.
Actually, such a procedure is hardly practicable. The number of culture elements is too great. Often too there would be doubt whether a feature should be reckoned as one or several. Metal working comprises smelting, casting, forging, alloying, plating, soldering, and welding. These are distinct techniques. Yet they usually occur together or are all lacking. One tribe practises simple two-ply twining. Another adds three-strand, diagonal, and lattice twining and three-strand braiding, probably as developments of the original two-strand process. As between two adjacent or related basket-making peoples, this difference may be very significant; measured against cloth weaving, it is trivial.
Accordingly, in order to render the data more easily apperceived and conceptualized, only the more fundamental aspects of arts and institutions have been included in the diagram ([Fig. 35]), plus some that perhaps involve intrinsically less significant principles or faculties, but were of particular importance in the life of the peoples following them, such as the tipi or skin tent of the Plains tribes. This means that a necessarily subjective selection of traits has been made in the compilation of the table. But the reader who is not a specialist in the matter will generally be grateful for the elimination; and this elimination has at least been conducted without a conscious bias in any one direction. If anything, it would seem that the selective condensation has operated against the preëminence of the advanced areas. With every possible datum inserted, the peaks in the table would probably overshadow the valleys much more conspicuously.
Accepting the diagram, then, as affording an approximately truthful picture, it is obvious that much the greatest advancement took place in Middle America—the region from Mexico to Peru; and that on the whole the majority of culture traits found in any of the more backward areas are shared with this middle region. These are the traits below the heavy line that steps up and down across the diagram. A minority of traits—those above the heavy line—are local to the several areas. On the basic principle that a trait occurring over a continuous territory may be assumed to have originated but once and to have spread by diffusion, the bulk of the culture of most of the areas must have come into them from outside. On the principle that a people with many established arts is more likely to make a new invention than is a retarded people, the great majority of the diffused elements may therefore be attributed to a Middle American source. In this region, then, lay the focal point, the hive, of American civilization. From it, the tribes of the Lower Amazon and the upper Mississippi equally derived most of the limited culture which they possessed.