Timing of Ectocranial Suture Activity in Pan troglodytes as Related to Cranial Volume and Dental Eruption
Article first published online: 14 MAY 2010
Copyright © 2010 Wiley-Liss, Inc.
The Anatomical Record
Volume 293, Issue 8, pages 1289–1296, August 2010
How to Cite
Cray, J., Mooney, M. P. and Siegel, M. I. (2010), Timing of Ectocranial Suture Activity in Pan troglodytes as Related to Cranial Volume and Dental Eruption. Anat Rec, 293: 1289–1296. doi: 10.1002/ar.21167
- Issue published online: 22 JUL 2010
- Article first published online: 14 MAY 2010
- Manuscript Accepted: 10 MAR 2010
- Manuscript Received: 7 SEP 2009
- cranial suture;
- Pan troglodytes;
- cranial volume;
- dental eruption;
Research has shown that Pan and Homo have similar ectocranial suture synostosis patterns possibly because of their phylogenetic relationship. However, unlike human data, it is unclear if the ontogeny of suture activity for Pan exhibits a relationship with the expanding neurocranium or the masticatory apparatus. These relationships were assessed by examining the associations between ectocranial suture status and morphology and cranial volume (as a proxy for neurocranial expansion) and dental development (as an indicator of adulthood and proxy for masticatory influence) in a large sample of Pan troglodytes skulls. One hundred and fifty-five P. troglodytes dry skulls were examined, and data were collected on ectocranial suture closure status, cranial volume, and dental eruption status. Regression models were calculated for suture status by cranial volumes, and Kendall's tau (a nonparametric measure of association) was calculated for suture status by dental eruption status. Results suggest that suture synostosis activity in P. troglodytes exhibits a period of stasis after neurocranial expansion cessation and does not have a strong relationship with brain development (r2 ranged from 0.09 to 0.28), as similarly seen in Homo. Instead, suture synostosis has a stronger relationship with dental development (τ ranged from 0.59 to 0.72), where most osseous activity occurs after full adult dental eruption. This suggests that masticatory forces may influence both ectocranial suture morphology and synostosis more than brain expansion does in Pan, as also similarly noted in Homo. Anat Rec 293:1289–1296, 2010. © 2010 Wiley-Liss, Inc.