(a) African, (b) East Asian, and (c) European clusters identified by SGA. The 51 population samples within HGDP were analyzed to identify homogeneous clusters using SGA applied to continental samples. Analysis was performed separately for each continent using SpectralGEM. Population labels were ignored in the analysis. The display is organized to emphasize when a population or group of populations falls into a common cluster. Groups of populations that fall into a common cluster are often from a common region; see Supplementary Figures 1 and 2.
