The effects of early agriculture on native North American populations: Evidence from the teeth and skeleton.

摘要

The advent of agriculture had significant repercussions for most aspects of human life. Determining when and why the switch to agriculture occupied and its effects on human biology is of continuing concern in anthropology. This study examined human populations before, during, and after the transition to agriculture to determine more precisely the timing and speed of change in subsistence patterns and the effect this change had on the population. Diet and health leave many traces in the skeleton: tooth wear and disease are affected by what individuals eat; bones may reflect the diet of an individual through analysis of stable isotope ratios.;The specific aims of this project were (1) to reconstruct the diet of the prehistoric people of Michigan; (2) to determine the level of dependence on maize during different periods and (3) to investigate the relationship of dental disease and wear to increasing dependence on maize. Populations in Michigan relied on maize to varying degrees because this region is at the edge of effective maize agriculture.;Diet in Michigan was reconstructed using archaeology, ethnohistory and stable isotope analysis. Reliance on maize was determined by analyzing carbon stable isotope ratios for individuals from sites before, during and after the adoption of maize. Sites in Michigan were assigned to groups based on the reconstructed diet. For most analyses, sites were designated as either primarily agricultural or hunter-gatherer based on the amount of maize.;All measures of dental disease (caries presence and severity, antemortem tooth loss and abscesses) were worse in the Michigan agricultural group as opposed to the hunter-gatherer group. Caries prevalence was highly correlated with the amount of maize consumed. Dental disease was a sensitive indicator of increased reliance on processed carbohydrates. Dental wear variables were not as sensitive as dental disease to subtle dietary differences. The Michigan agricultural group differed in dental wear in the expected manner from the hunter-gatherer group, although differences were small. Results from stable isotope analysis, dental disease and tooth wear all indicated that maize became an important resource in many regions, although wild resources also remained significant.