Climate and Diet in Fremont Prehistory: Economic Variability and Abandonment of Maize Agriculture in the Great Salt Lake Basin

Abstract

Research reported here is based on the stable isotope (δ13C,δ15N) and radiocarbon chemistry of Fremont burials from wetlands lining the eastern shores of the Great Salt Lake (GSL). Bone collagen stable isotope signatures covary with reliance on maize and intake of animal protein, facilitating useful reconstructions of past diet. Among the GSL Fremont, economic strategies vary over time with an initial increase in reliance on maize (A.D. 400–850) followed by a period of marked economic diversity (A.D 850–1150) then a return to reliance on wild foods (after A.D. 1150). During the period of greatest economic diversity, male and female diets vary significantly and male diets are correlated with status differences evidenced by grave goods. There is also a clear temporal correlation between the rapid abandonment of maize agriculture and significant moisture anomalies in regional tree-ring chronologies and pollen profiles. These results are discussed in the context of recent arguments regarding economic diversity, social complexity, and the demise of the Fremont.