Ecology Explains a Substantial Amount of Human Cultural Variation Around the Globe.

How strong is the association between ecological conditions and cultural variation? The present work provides a systematic test of associations between nine key ecological variables and 72 cultural variables (including values, personality traits, norms, behaviors, and societal practices and features) across 220 countries. This approach enables us to generate a range of estimates designed to capture the strength of this association. Our results suggest that ecological conditions account for a substantial amount of the cultural variation observed across human groups (R2 from 0.28 to 0.47 and adjusted R2 from 0.05 to 0.28. We also explore the extent to which specific ecological features may be more or less related to cultural variation in general, and the extent to which specific cultural variables may be more or less strongly related to ecology in general. Importantly, our findings hold when controlling for spatial autocorrelation and other confounds, such as variable selection.