Parietal bone thickness and vascular diameters in adult modern humans: a survey on cranial remains

Abstract

Cranial bone thickness varies among modern humans, and many factors influencing this variability remain unclear. Growth hormones and physical activity are thought to influence the vault thickness. Considering that both systemic factors and energy supply influence the vascular system, and taking into account the structural and biomechanical interaction between endocranial vessels and vault bones, in this study we evaluate the correlation between vascular and bone diameters. In particular, we tested the relationship between the thickness of the parietal bone (which is characterized, in modern humans, by a complex vascular network) and the lumen size of the middle meningeal and diploic vessels, in adult modern humans. Our results show no patent correlation between the thickness of parietal bone and the size of the main vascular channels. Values and distributions of the branching patterns, as well as anatomical relationships between vessels and bones, are also described in order to provide information concerning the arrangement of the endocranial vascular morphology. This information is relevant in both evolutionary and medical contexts.