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Updated: Jun 17, 2026
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Primer Extension Capture: Targeted Sequence Retrieval from Heavily Degraded DNA Sources
Published on: September 3, 2009
Revising the recent evolutionary history of equids using ancient DNA
Ludovic Orlando1, Jessica L Metcalf, Maria T Alberdi
1Institut de Génomique Fonctionnelle de Lyon, Université de Lyon 1, Ecole Normale Supérieure de Lyon, and Institut National de la Recherche Agronomique, Centre National de la Recherche Scientifique, 69364 Lyon Cédex 07, France. ludovic.orlando@ens-lyon.fr
Summary
Ancient DNA analysis of fossil horses (Equidae) reveals unexpected evolutionary relationships and necessitates revisions in equid taxonomy. This study uncovers new species and clarifies the status of extinct zebras.
Area of Science:
- Paleontology
- Molecular Evolution
- Genomics
Background:
- The family Equidae, crucial for studying macroevolution, has an extensive fossil record but unresolved phylogenetic relationships and taxonomy.
- Recent ancient DNA studies on extinct equids indicate a need for significant taxonomic and phylogenetic revisions.
Purpose of the Study:
- To investigate equid evolutionary history and taxonomy using ancient DNA (aDNA) from fossil specimens.
- To resolve phylogenetic uncertainties and identify new species within the Equidae family.
Main Methods:
- Analysis of 87-688 bp of mitochondrial aDNA from 22 ancient equid specimens across four continents.
- Phylogenetic analyses to reconstruct evolutionary relationships.
Main Results:
- Phylogenetic analyses support major revisions to recent equid evolutionary history.
- Discovery of two new equid species, including a South American hippidion.
- The extinct Cape zebra (Equus capensis) is nested within modern plain zebras, alongside the quagga.
- Revised extinction timings for two hemione-related equid groups.
Conclusions:
- Ancient DNA analysis is crucial for resolving equid taxonomy and evolutionary history.
- A rapid DNA barcoding approach is proposed for evaluating Late Pleistocene equid species described solely on morphology.
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