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Updated: Jun 28, 2025
A Morphometric and Cellular Analysis Method for the Murine Mandibular Condyle
Published on: January 11, 2018
Revisiting mandibular symphyseal shape in juvenile early hominins and modern humans using a deformation-based
Veronika A Zimmer1, Anna Oettlé2, Jakobus Hoffmann3
1School of Computation, Information and Technology, 9184Technical University of Munich, Boltzmannstraße 3, 85748 Garching, Germany.
Abstract:
The juvenile mandible is important in the investigation of ontogenetic and evolutionary changes among early hominins. We revisit the mandibular symphysis in juvenile specimens of Australopithecus africanus and Paranthropus robustus with two main contributions. First, we employ, for the first time, methods of computational anatomy to model complex symphyseal shape differences. Second, we present new fossil evidence from Kromdraai to improve our knowledge of symphyseal morphology. We describe differences between shapes by landmark-free diffeomorphism needed to align them. We assess which features of the mandibular symphysis best discriminate the juvenile symphysis in these fossil species, relative to the intraspecific variation observed among modern humans. Our approach eliminates potential methodological inconsistencies with traditional approaches (i.e., the need for homologous anatomical landmarks, assumption of linearity). By enabling detailed comparisons of complex shapes in juvenile mandibles, our proposed approach offers new perspectives for more detailed comparisons among Australopithecus, Paranthropus and early Homo.
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