Fig. 1: Geographic and temporal distribution of samples included in this study.

A The continent of origin for all samples included in this study. Point shape and color indicate sample type, while point size indicates the number of samples. The two points in the lower right corner represent museum specimens for which the geographic origin is uncertain. B Temporal origin of ancient dental calculus samples separated by continent. Samples are indicated by a tick mark across the line for each continent, binned per 200 years. Histograms demonstrate the ages with the highest density of sample counts. The majority of samples from all continents are from ≤ 1000 BP (Before Present).