Fig. 4

Boxplots of predicted prevalence of slow acetylators in populations classified according to subsistence mode and further to ecoregion. Each box extends from the first to the third quartile and displays the median (thick line), and the dispersion of populations’ individual values (filled circles) is shown by dashed lines. (a) Thirty-eight African populations (AFR dataset); (b) same dataset crossed with biome information, i.e., separating populations living in the seasonally dry zones (Sahel, Savanna) from those living in the humid tropical and equatorial zones; (c) same cross-analysis as in (b) but excluding population samples of less than 20 individuals