Carious lesions as evidence for different adaptation strategies during the middle-late Holocene in the Gansu region, northwest China

The natural environment of the Gansu-Qinghai region in northwest China exhibits spatial variation, resulting in distinct adaptive strategies among populations in different geographical areas. In this study, we analyzed the diachronic trend and regional variations in caries prevalence among 10 different middle and late-Holocene groups by examining dental caries data to explore the correlation between different adaptation strategies and caries frequency. Frequency data was used to compare dental caries between populations, and the Chi-square test was employed to detect statistical differences. A multidisciplinary approach was employed to investigate the relationship between these changes and the adaptive strategies adopted by the populations in this region. The result shows that there was a gradual increase in caries prevalence over time in eastern Gansu, which corresponded with development of millet farming and social hierarchy. In the Hexi Corridor, caries prevalence exhibited fluctuations attributable to climate variability, human migration, and regime change. The research proposes that changes in adaptive strategies due to various social and environmental factors are reflected in human teeth, while also presenting a novel endeavor of aggregating a large, multisite bioarchaeological dataset in order to investigate the interactions between Holocene populations and palaeoenvironments in northwest China.