Adolescent growth halt explains modern human and Neanderthal facial differences

Modern humans' flatter faces, unlike Neanderthals', result from a premature halt in midface growth during adolescence. This difference in growth timing, observed in a Max Planck Institute study of skulls, leads to a more robust, protruding face in Neanderthals and chimpanzees due to prolonged bone development. The study analyzed 128 human, 33 chimpanzee, and 13 Neanderthal skulls, suggesting growth timing, not a single trait, explains facial differences.