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Updated: Jul 15, 2026
07:26
Systematic Assessment of Mammalian Skull Specimens for Dental and Temporomandibular Joint Pathology
Published on: August 22, 2022
Convergence and remarkably consistent constraint in the evolution of carnivore skull shape
1School of Biological, Earth, and Environmental Sciences, The University of New South Wales, Sydney, Australia. s.wroe@unsw.edu.au
Summary
Convergent evolution is supported by skull shape similarities in marsupials and placentals, revealing adaptive evolution despite differing evolutionary constraints influencing cranial shape.
Area of Science:
- Evolutionary biology
- Comparative anatomy
- Paleontology
Background:
- Phenotypic similarities between marsupials and placentals are often cited as examples of convergent evolution.
- Adaptive evolution is considered a key driver of morphological and ecological diversity.
Purpose of the Study:
- To compare skull shape in carnivoran placentals and nonherbivorous marsupials using three-dimensional (3-D) geometric morphometrics.
- To investigate convergence across a broader range of feeding ecologies, including extinct taxa and non-dasyuromorphian marsupials.
Main Methods:
- Utilized a three-dimensional (3-D) geometric morphometric approach to analyze skull shape.
- Compared skull morphology, feeding behavior, and bite force across diverse marsupial and placental carnivoran samples.
Main Results:
- Found support for the adaptive paradigm, with correlations between skull morphology, feeding behavior, and bite force.
- Skull shape was a better predictor of feeding ecology in marsupials than in placentals.
- Identified consistent but differing evolutionary constraints on cranial shape in both groups, correlating with brain size and bite force.
Conclusions:
- Skull shape evolution in marsupials and placentals is influenced by both adaptive pressures and distinct evolutionary constraints.
- These constraints, related to brain size and bite force, are maintained across various feeding categories and morphologies.
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