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Changes in orientation of attritional wear facets with implications for jaw motion in a mixed longitudinal sample of Propithecus edwardsi from Ranomafana National Park, Madagascar.

Publication ,  Journal Article
Blatch, S; Boyer, DM; King, SJ; Bunn, JM; Jernvall, J; Wright, PC
Published in: American journal of physical anthropology
September 2011

In many mammalian species, the progressive wearing down of the teeth that occurs over an individual's lifetime has the potential to change dental function, jaw movements, or even feeding habits. The orientation of phase-I wear facets on molars reveals the direction of jaw movement during the power stroke of mastication. We investigated if and how molar wear facets change with increasing wear and/or age by examining a mixed longitudinal dataset of mandibular tooth molds from wild Propithecus edwardsi (N = 32 individuals, 86 samples). Measurements of the verticality of wear facets were obtained from three-dimensional digital models generated from μCT scans. Results show that verticality decreases over the lifetime of P. edwardsi, a change that implies an increasingly lateral translation of the jaw as the teeth move into occlusion. A more transverse phase-I power stroke supports the hypothesis that these animals chew to maximize longevity and functionality of their teeth, minimizing the "waste" of enamel, while maintaining sharp shearing crests. Results of this study indicate that wear facet verticality is more closely correlated with age than overall amount of tooth wear, measured as area of exposed dentin, suggesting that age-related changes in cranial morphology may be more responsible for adjustments in jaw motion over the lifetimes of Propithecus than wear-related changes inthe shape of occluding teeth. Finally, the rate of decrease in wear facet verticality with age is greater in males than in females suggesting differences in development and/or access to resources between the sexes in this species.

Duke Scholars

Published In

American journal of physical anthropology

DOI

EISSN

1096-8644

ISSN

0002-9483

Publication Date

September 2011

Volume

146

Issue

1

Start / End Page

116 / 133

Related Subject Headings

  • X-Ray Microtomography
  • Tooth Attrition
  • Strepsirhini
  • Statistics, Nonparametric
  • Sex Factors
  • Molar
  • Mastication
  • Male
  • Madagascar
  • Female
 

Citation

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Blatch, S., Boyer, D. M., King, S. J., Bunn, J. M., Jernvall, J., & Wright, P. C. (2011). Changes in orientation of attritional wear facets with implications for jaw motion in a mixed longitudinal sample of Propithecus edwardsi from Ranomafana National Park, Madagascar. American Journal of Physical Anthropology, 146(1), 116–133. https://doi.org/10.1002/ajpa.21565
Blatch, Stephanie, Doug M. Boyer, Stephen J. King, Jonathan M. Bunn, Jukka Jernvall, and Patricia C. Wright. “Changes in orientation of attritional wear facets with implications for jaw motion in a mixed longitudinal sample of Propithecus edwardsi from Ranomafana National Park, Madagascar.American Journal of Physical Anthropology 146, no. 1 (September 2011): 116–33. https://doi.org/10.1002/ajpa.21565.
Blatch S, Boyer DM, King SJ, Bunn JM, Jernvall J, Wright PC. Changes in orientation of attritional wear facets with implications for jaw motion in a mixed longitudinal sample of Propithecus edwardsi from Ranomafana National Park, Madagascar. American journal of physical anthropology. 2011 Sep;146(1):116–33.
Blatch, Stephanie, et al. “Changes in orientation of attritional wear facets with implications for jaw motion in a mixed longitudinal sample of Propithecus edwardsi from Ranomafana National Park, Madagascar.American Journal of Physical Anthropology, vol. 146, no. 1, Sept. 2011, pp. 116–33. Epmc, doi:10.1002/ajpa.21565.
Blatch S, Boyer DM, King SJ, Bunn JM, Jernvall J, Wright PC. Changes in orientation of attritional wear facets with implications for jaw motion in a mixed longitudinal sample of Propithecus edwardsi from Ranomafana National Park, Madagascar. American journal of physical anthropology. 2011 Sep;146(1):116–133.
Journal cover image

Published In

American journal of physical anthropology

DOI

EISSN

1096-8644

ISSN

0002-9483

Publication Date

September 2011

Volume

146

Issue

1

Start / End Page

116 / 133

Related Subject Headings

  • X-Ray Microtomography
  • Tooth Attrition
  • Strepsirhini
  • Statistics, Nonparametric
  • Sex Factors
  • Molar
  • Mastication
  • Male
  • Madagascar
  • Female