Different environmental variables predict body and brain size evolution in Homo

Abstract Increasing body and brain size constitutes a key macro-evolutionary pattern in the hominin lineage, yet mechanisms behind these changes remain debated. Hypothesized drivers include environmental, demographic, social, dietary, technological factors. Here we test influence of environmental factors on evolution genus Homo over last one million years using large fossil dataset combined with global paleoclimatic reconstructions formalized hypotheses tested quantitative statistical framework. We identify temperature as major predictor variation within , accordance Bergmann’s rule. In contrast, net primary productivity environments long-term variability precipitation correlate but explain low amounts observed variation. These associations are likely due to an indirect cognitive abilities extinction probabilities. Most that do not correspond evolution, pointing towards complex scenarios which underlie biological characteristics later .