Ontogeny of sphenoidal, occipital, and temporal bone morphology in humans

Abstract

Previous research suggests that the basicranium ossifies early in ontogeny and reflects phylogeny, but the process by which the various basicranial subregions develop is currently unknown. The 3D basicranial landmarks on the sphenoid, temporal, and occipital of 266 subadults and adults in seven populations were collected and compared. The seven populations were found to be significantly different in basicranial morphology in specimens over 5 years old, and those differences significantly reflected their published molecular distances. The differences in morphology significantly reflected genetic distances in childhood, but not adulthood. The occipital bone showed significant differences in morphology in children, and significantly reflected genetic distances; however, this pattern did not continue into adulthood. Temporal bone age categories reflected genetic distances if the Egyptian population was excluded. In sphenoid, the differences among groups were uncorrelated with genetic distances. These results indicate that the morphology of the entire basicranium reflects molecular distances and that this pattern becomes established early in ontogeny. However, the three basicranial regions develop along differing ontogenetic trajectories. Greater landmark density is preferable when using basicranial morphology to reconstruct population history.Grant Funding Source: Midwestern University