The Human Mandible and the Origins of Speech

Figure 8

Chin size (mm²) relative to bicanine breadth (mm) for a mixed-sex sample of adult modern humans from the Tigara (𝑁=57) and El Hesa (𝑁=51) collections. Daegling [14] hypothesized that bicanine breadth would covary positively with chin size as this represented the portion of the anterior corpus loaded in coronal bending due to twisting of the postcanine corpora. Regression is significant at 𝑃=0.04; however, 𝑟²=0.04, indicating that little of the variation in chin size is explicable by variation in bicanine breadth.