Study shows modern horses are genetically quite different from the horses of just a few hundred years ago. Two additional now-extinct lineages of horses were identified; one from the Iberian Peninsula and one from Siberia, both of which still existed 4,000-4,500 years ago.

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Study shows modern horses are genetically quite different from the horses of just a few hundred years ago. Two additional now-extinct lineages of horses were identified; one from the Iberian Peninsula and one from Siberia, both of which still existed 4,000-4,500 years ago.