The findings in chimpanzees indicate that both humans and chimpanzees exhibit population-level asymmetries in handedness, though humans show more pronounced lat

The findings in chimpanzees indicate that both humans and chimpanzees exhibit population-level asymmetries in handedness, though humans show more pronounced lateralization (e.g. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3676728 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3676728). I think this suggests that anatomical asymmetries in the brain likely preceded handedness and contributed to the evolution of hemispheric specialization. As brain size increased and corpus callosum connectivity decreased, specialized functions in each hemisphere became more pronounced. Thus, handedness and brain asymmetry likely co-evolved, influenced by both genetic and environmental (including socio-cultural) factors, rather than one directly causing the other.