Beyond Bergmann's rule: Global variability in human body composition is associated with annual average precipitation and annual temperature volatility

Objectives Human populations exhibit substantial geographical variability in body size and shape. However, the ecological stresses underlying this morphological variability remain poorly understood. The prevailing evolutionary explanation, “Bergmann's rule” assumes that morphological variability represents an adaptive response to average thermal conditions. We hypothesized that other climate factors—annual average precipitation, a marker of...