Because the composition of bone collagen is affected by diet, paleoanthropologists have used analyses of both trace elements and isotopic ratios in skeletal remains in an attempt to reconstruct patterns of subsistence. In particular, this approach has been employed to study the adoption of maize agriculture among North American Indians. Changes in hypothesized diets have then been correlated with changes in social organization. Because maize has a slightly different ratio of carbon isotopes from most native North American vegetation, paleoanthropologists have used variation in carbon 12/13 ratios as an indicator of the amount of maize in the diet. While, from an empirical perspective, the results appear reasonable, many details of the system are not fully understood. Dr. Margaret Schoeninger's work is directed to filling in the blanks. Dr. Schoeninger will carry out a number of related activities. She will study modern samples of prehistoric strains and determine isotope ratios. She will then subject such samples to burning and other diagenetic factors to see if they affect the ratio. She will also analyze a series of materials recovered from archaeological sites which also contain maize remains. Bone collagen stable isotope ratios will be determined. Maize kernels will then be analyzed for overall isotopic composition, as well as the isotopic composition of individual biochemical components and individual amino acids. This research is important for several reasons. First, it will help to develop techniques which may be used to investigate a number of archaeological situations. Secondly, it will increase our understanding of U.S. prehistory. Finally, because the project includes students, it will assist in the training of young scientists.
