Culture change on the eastern margins of the Southern Plain

This study examines cultural variation in the central Washita River basin between A.D. 900 and 1450 and the interaction of social, economic, and environmental factors that led to selection for a sedentary, horticultural/bison hunting adaptation. Selectionist models for the development of agricultural systems have emphasized the process of productive specialization. The identification of early horticultural villages in central Oklahoma provides a data base to compare changes through the Late Prehistoric period and analyze the process of economic specialization in this part of the Southern Plains.;The study focuses on the Paoli phase. Plant and animal remains from these sites provide evidence for intensive cultivation of corn and possibly other native crops along the eastern edge of the prairie plains by about A.D. 1000. Material culture is used to suggest the local evolution of this society from Plains Woodland groups with some changes in artifacts tied to selection of technologies needed for processing or storing crops. Chronometric data as well as artifactual, architectural, and settlement information also reveal the changes that occur through time leading to the typical Plains Village adaptation of the later Washita River phase (A.D. 1250-1450).;The economic specialization associated with the development of corn horticulture resulted in a localization of resource exploitation during the early Paoli phase. Deer and aggregate riverine resources, primarily fish and mussels, provided the major game, and exploitation of lithic resources was confined principally to local gravels. However, through time population growth related to agricultural intensification and changing climatic conditions modified the costs and risks associated with exploitation of various resources resulting in the intensification of bison hunting. Among the factors that influenced this development, the most significant may have been the increasingly dry conditions that arose during the Late Prehistoric period and increased the risks of periodic crop failure. The same drying conditions resulted in the expansion of mixed and short grasses into areas previously dominated by tall grass prairie. The spread of shorter grasses favored by bison led to increases in bison herds on the eastern prairie plains providing villagers with greater access to a high-yield and/or more predictable resource.