Subsistence Practices and the Occupational Histories of the Little Green Valley: A Prehistoric Central Arizona Frontier

The Transitional Zone of central Arizona is a mountainous region dissected by rivers that created barriers and drove movement between prehistoric Hohokam groups to the south and Ancestral Peoples groups to the northeast and northwest. Although never suitable for large-scale agricultural irrigation, this region provided small areas of arable land scattered across rugged terrain rich in wild foods and alboreal resources. Archaeological data recovery related to road improvement projects throughout Arizona Route 260 allowed us to examine paleobotanical and osteofaunal remains of five archaeological sites. We relate changes in diet breadth and anthropogenic land effects modeled and described using the methods of the optimal foraging theory, with modes of use modeled using concepts from the frontier theory. We found that brief intervals of prey suppression and concomitant expansion of diet breadth between low value resources coincide with intervals of prey recovery and diet amplitude contraction between low value resources and more intensive settlement. On the other hand, ranges of prey recovery and diet breadth contraction among low value resources coincide with a reduced population and seasonal, extractive, and short-term occupations.