How Allometry and Sexual Dimorphism Influence Cortical Bone Morphology at the Mandibular Symphysis in Modern Humans: A Comparative Study Using Elliptic Fourier Descriptors.
- 1UFR des Sciences odontologiques, Université de Bordeaux, Bordeaux, France.
- 2CNRS, Ministère de la Culture, PACEA, UMR 5199, Université de Bordeaux, Pessac, France.
Abstract
Objectives
The modern human mandibular symphysis displays a mental prominence, a unique trait in the human lineage. Beyond this shared pattern, considerable variability in shape and metrics exists. This heterogeneity is thought to result from multiple mechanisms, including biomechanical compensation, allometric and dietary effects, population genetics, or sexual dimorphism. While the influence of these processes on overall mandibular shape is thoroughly documented, limited information exists on their effects on the distribution of mandibular cortical bone. Thus, this study assessed the impact of local and global allometry, sexual dimorphism, and cortical area on the shape and size of the symphyseal cortical bone contours.Methods
We analyzed computed tomography images of 62 modern human mandibles using Elliptic Fourier Descriptors. The effects of the investigated variables on external and internal cortical bone shapes and sizes were tested using a nested multivariate approach and predicted shape reconstructions were used to visualize morphological variation.Results
In this sample, sex, and local allometry had significant effects on mandibular symphyseal shape and sex was the main predictor of local allometry. Cortical area significantly affected the shape and size of the external cortical bone contour and body weight influenced the size of the internal cortical bone contour.Conclusion
Sexual dimorphism, allometric effects, and biomechanical compensation impact the shape and size of the mandibular symphysis. External and internal cortical bone contours respond differently to these effects. Future studies could investigate the influence of other relevant factors on symphyseal shape and size.
Related
- The role of root allometry and root overlap in vegetation pattern formation
- Dimension reduction for characterizing sexual dimorphism in biomechanics of the temporomandibular joint
- Comparison of degree and modified reverse degree descriptors incorporating entropy and graph energy analysis for graphene allotropes
- Descriptors of Two-Dimensional Fuzzy Geometric Objects
- Decoy and disclosure radii of invariant shape descriptors
BibTeX
@article{degabriel2026allometry,
title = {{How Allometry and Sexual Dimorphism Influence Cortical Bone Morphology at the Mandibular Symphysis in Modern Humans: A Comparative Study Using Elliptic Fourier Descriptors.}},
author = {Carla Degabriel and Ana Ribeiro and Anaïs Cavaré and Christine Couture and Pierre-Hadrien Decaup},
journal = {American journal of biological anthropology},
year = {2026},
month = oct,
doi = {10.1002/ajpa.70376},
url = {https://europepmc.org/article/MED/42958926},
note = {CC BY-NC-ND},
}
RIS
TY - JOUR
TI - How Allometry and Sexual Dimorphism Influence Cortical Bone Morphology at the Mandibular Symphysis in Modern Humans: A Comparative Study Using Elliptic Fourier Descriptors.
AU - Carla Degabriel
AU - Ana Ribeiro
AU - Anaïs Cavaré
AU - Christine Couture
AU - Pierre-Hadrien Decaup
PY - 2026
DA - 2026/10/30
JO - American journal of biological anthropology
DO - 10.1002/ajpa.70376
UR - https://europepmc.org/article/MED/42958926
AB - Objectives The modern human mandibular symphysis displays a mental prominence, a unique trait in the human lineage. Beyond this shared pattern, considerable variability in shape and metrics exists. This heterogeneity is thought to result from multiple mechanisms, including biomechanical compensation, allometric and dietary effects, population genetics, or sexual dimorphism. While the influence of these processes on overall mandibular shape is thoroughly documented, limited information exists on their effects on the distribution of mandibular cortical bone. Thus, this study assessed the impact of local and global allometry, sexual dimorphism, and cortical area on the shape and size of the symphyseal cortical bone contours.Methods We analyzed computed tomography images of 62 modern human mandibles using Elliptic Fourier Descriptors. The effects of the investigated variables on external and internal cortical bone shapes and sizes were tested using a nested multivariate approach and predicted shape reconstructions were used to visualize morphological variation.Results In this sample, sex, and local allometry had significant effects on mandibular symphyseal shape and sex was the main predictor of local allometry. Cortical area significantly affected the shape and size of the external cortical bone contour and body weight influenced the size of the internal cortical bone contour.Conclusion Sexual dimorphism, allometric effects, and biomechanical compensation impact the shape and size of the mandibular symphysis. External and internal cortical bone contours respond differently to these effects. Future studies could investigate the influence of other relevant factors on symphyseal shape and size.
SN - 2692-7691
ER -