Horses lived in the Americas for millions of years – new research helps paleontologists understand the fossils we’ve found and those that are missing from the record

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Stephanie Killingsworth, University of Florida and Bruce J. MacFadden, University of Florida

(THE CONVERSATION) Many people assume that horses first came to the Americas when Spanish explorers brought them here about 500 years ago. In fact, recent research has confirmed a European origin for horses associated with humans in the American Southwest and Great Plains.

But those weren’t the first horses in North America. The family Equidae, which includes domesticated varieties of horses and donkeys along with zebras and their kin, is actually native to the Americas. The fossil record reveals horse origins here more than 50 million years ago, as well as their extinction throughout the Americas during the last Ice Age about 10,000 years ago.

We are paleontologistswho focus our research on various types of fossils, including ancient horses. Our most recent work used computer statistics to analyze gaps in the fossil record to...