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Title: Allometry and advancing age significantly structure craniofacial variation in adult female baboons
Abstract

Primate craniofacial growth is traditionally assumed to cease upon maturation or at least be negligible, whereas bony remodeling is typically associated with advanced adult age and, in particular, tooth loss. Therefore, size and shape of the craniofacial skeleton of young and middle‐aged adults should be stable. However, research on both modern and historic human samples suggests that portions of theCFSexhibit age‐related changes in mature individuals, both related to and independent of tooth loss. These results demonstrate that the age‐category ‘adult’ is heterogeneous, containing individuals demonstrating post‐maturational age‐related variation, but the topic remains understudied outside of humans and in the cranial vault and base. Our research quantifies variation in a sample of captive adult female baboons (= 97) in an effort to understand how advancing age alters the matureCFS. Craniometric landmarks and sliding semilandmarks were collected fromcomputed tomography (CT)scans of adult baboons aged 7–32 years old. To determine whether craniofacial morphology is sensitive to aging mechanisms and whether any such effects are differentially distributed throughout the cranium, geometric morphometric techniques were employed to compare the shapes of various cranial regions among individuals of increasing age. Unexpectedly, the biggest form differences were observed between young and middle‐aged adults, rather than between adults with full dentitions and those with some degree of tooth loss. Shape variation was greatest in masticatory and nuchal musculature attachment areas. Our results indicate that thecraniofacial skeletonchanges form during adulthood in baboons, raising interesting questions about the molecular and biological mechanisms governing these changes.

 
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NSF-PAR ID:
10101640
Author(s) / Creator(s):
 ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
Journal of Anatomy
Volume:
235
Issue:
2
ISSN:
0021-8782
Page Range / eLocation ID:
p. 217-232
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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