Integrating dental microwear and isotopic analyses to understand dietary change in east-central Mississippi

Abstract

Stable isotope and dental microwear analyses are integrated to observe changes in plant food diet in east-central Mississippi. Dental specimens are compared from seven sites in Mississippi and one in Alabama ranging in time from the Archaic to the Protohistoric periods. Microwear analysis of phase II dental facets is performed and pit percentages, scratch length and width, and pit length and width are recorded. Analysis of variance statistical tests were performed between temporally contiguous sites. The results indicate that the size and frequency of microwear features decrease through time until the Protohistoric period where pit feature size and frequencies increase significantly. These results are then compared to stable isotope analysis to test whether the methods yield congruent results and to assess additional dietary changes, specifically the increased importance of nut foods. Carbon isotope analysis indicates differences in dietary maize use between the Mississippian and Protohistoric samples and dental microwear analysis show a significant increase in pit percentages and pit size, microwear features generally associated with hard food mastication. One important question addressed is whether there was a return in the Protohistoric period to naturally available resources, specifically hard foods such as nuts, a pattern observed at sites in Alabama and Arkansas. The use of secondary burials in the later Protohistoric period is examined as a possible cause for this microwear pattern. The study demonstrates the importance of integrating different methods when assessing dietary change, especially when ethnobotanical information is not available.