Ectocranial suture fusion in primates: as related to cranial volume and dental eruption

Background Timing of calvarial suture fusion is important in primate ontogeny. Ages at death are difficult to assess especially for museum collections. Methods 1550 skulls of Hominoid, Hylobatidae, Macaca and Papio were observed for fusion. Calvarial expansion (early) and dental eruption (late) were utilized as indicators of ontogeny. Homogeneity of slopes and ANOVA were used to determine differences in timing of fusion. Results For calvarial growth the great apes all showed small levels of calvarial suture remodeling prior to full calvarial expansion. For dental eruption, Homo and Macaca share a common pattern of fusion in late adulthood. The other species show early remodeling. Papio was observed to have distinct patterns for suture fusion progression. Conclusions Thus, suture fusion progression although influenced by evolutionary changes in the robusticity of the craniofacial skeleton can be modeled by the phylogeny among this group. Overall, Homo appears to have a distinct pattern of delayed suture fusion progression.