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Eurasian wild asses in time and space: morphological versus genetic diversity
Eva-Maria Geigl1, Thierry Grange
1Institut Jacques Monod, UMR CNRS Université Paris Diderot, France. geigl.eva-maria@ijm.univ-paris-diderot.fr
Summary
Ancient DNA analysis challenges traditional classification of wild asses (Equidae). Morphological traits alone are unreliable for distinguishing species, revealing significant genetic diversity and plasticity in Equus.
Area of Science:
- Paleontology
- Genetics
- Zoology
Background:
- The taxonomy of Equidae, particularly extinct species, is controversial due to reliance on morphology.
- Understanding the evolutionary history and genetic diversity of extinct wild asses is crucial but challenging.
Purpose of the Study:
- To investigate the phylogeography of wild asses using ancient mitochondrial DNA.
- To reassess the reliability of morphological criteria in equid species classification.
Main Methods:
- Analysis of ancient mitochondrial DNA from fossil equid bone remains.
- Phylogeographic reconstruction across the former geographic range of wild asses.
- Comparison of genetic data with morphological classifications.
Main Results:
- Identified diverse mitochondrial lineages within morphologically similar wild ass populations.
- Revealed genetic similarities between morphologically distinct equid animals.
- Demonstrated significant morphological plasticity among Equus species.
Conclusions:
- Morphological criteria alone are insufficient and can be unreliable for classifying fossil equid species.
- Ancient DNA analysis provides critical insights into equid evolutionary history and diversity.
- Re-evaluation of equid taxonomy integrating genetic and morphological data is necessary.
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