Cranial vault thickness in non-human primates: Allometric and geometric analyses of the vault and its component layers

Total frontal and parietal CVT scales with positive allometry or isometry with measures of size across a combined non-human primate sample, although some variation exists within each infraorder and when diploë thickness alone is compared to measures of size. CVT in this sample correlates weakly with cranial vault shape, but the relationship described here contradicts an earlier hypothesis that long, low vaults should be thicker than higher, globular vaults. This study provides new data on the variation of vault morphology among extant primates that may be used to inform future hypotheses for the cranial vault hypertrophy of H. erectus.