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Conical and sabertoothed cats as an exception to craniofacial evolutionary allometry
Davide Tamagnini1,2, Margot Michaud3, Carlo Meloro4
1Department of Biology and Biotechnologies "Charles Darwin", University of Rome "La Sapienza", Zoology Building, Viale dell'Università 32, 00185, Rome, Italy. davide.tamagnini@uniroma1.it.
Scientific Reports
|August 21, 2023
Summary
Craniofacial Evolutionary Allometry (CREA) generally holds true for felids, but extinct saber-toothed cats (Machairodontinae) are a notable exception, likely due to unique adaptations.
Area of Science:
- Evolutionary biology
- Comparative anatomy
- Paleontology
Background:
- Phenotypic diversity is shaped by evolutionary trends over macroevolutionary scales.
- Craniofacial Evolutionary Allometry (CREA) describes a pattern where smaller species have proportionally shorter rostra and larger braincases.
- The validity of CREA in felids, including extinct species, requires further investigation.
Purpose of the Study:
- To assess the validity and strength of CREA in extinct and living felids.
- To investigate the influence of biomechanical constraints, specifically relative canine height, on cranial shape evolution.
- To identify potential exceptions to CREA within the Felidae family.
Main Methods:
- Utilized a phylogenetically broad cranial dataset of felids.
- Employed 3D geometric morphometrics to analyze cranial shape.
- Applied phylogenetic comparative methods to test evolutionary hypotheses.
Main Results:
- CREA is supported at the Felidae family level.
- Living felines largely conform to CREA predictions.
- Extinct big cats, Pantherinae and Machairodontinae, show weak or no conformity to CREA.
Conclusions:
- Machairodontinae represent a significant exception to CREA, likely due to specialized rostral adaptations.
- Extreme features related to biomechanics, evo-devo, and ecology can lead to exceptions to common evolutionary rules.
- Heterochronic changes and variations in evolutionary integration may explain deviations from established patterns.
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