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A morphological analysis of carnivoran ossicles from Rancho La Brea
Edwin Dickinson1,2, Erin E Elminowski1,3, Deanna Flores1,4,5
1Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina, USA.
Journal of Morphology
|August 30, 2022
Summary
Fossil carnivoran middle ear ossicle morphology was analyzed. Fossil canids and felids closely resemble living relatives, while fossil ursids show significant size differences.
Area of Science:
- Paleontology
- Comparative Anatomy
- Bioacoustics
Background:
- Mammalian middle ear ossicle morphology influences auditory capabilities.
- Fossil carnivoran ossicle data is limited, hindering evolutionary auditory studies.
Purpose of the Study:
- To present the first morphological data for fossil carnivoran ossicles from Rancho La Brea.
- To compare fossil ossicle morphology with extant relatives (felids, canids, ursids).
Main Methods:
- Collected linear measurements from fossil Smilodon fatalis, Panthera atrox, Canis dirus, Arctodus simus ossicles (malleus, incus, stapes).
- Utilized geometric means and principal components analyses for morphological comparisons.
- Contextualized fossil data with extant felid, canid, and ursid samples.
Main Results:
- Fossil canid and felid ossicles are similar in size to extant analogs.
- Arctodus simus ossicles are significantly larger than extant ursids.
- Principal components analyses show close affinities for fossil/extant canids and felids, but greater disparity for ursids.
Conclusions:
- Fossil and extant carnivoran middle ear morphology reveals distinct evolutionary paths, particularly in ursids.
- Further fossil ossicle discoveries are crucial for refining interpretations of auditory variation.
- Preservation of these small fossil elements is vital for understanding mammalian auditory evolution.
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