The first ancient horses lived in forests 55 million years ago, both in Europe and America. At that time they were the size of dogs.
Horses resembling the ones we know today evolved in North America. From there they spread to Asia and Europe.
This migration happened between one million and 800 000 years ago, according to a new genetic study published in the journal Molecular Ecology.
If the ancient horses hadn’t made their way to Eurasia, there probably wouldn’t be any horses today.
The researchers analysed ancient genetic material. It turns out that horses from Eurasia and North America actually intermingled following the first dispersal.
This connectivity was possible when the ocean level was low, creating a land bridge where the Bering Strait is today. The land bridge connected Siberia and Alaska.
“We found out that the populations of horses travelled across the land bridge when it existed. But not only that, they intermingled as well. They weren’t totally isolated from each other,” says [researcher Peter] Heintzman.
“This finding indicates that North American and Eurasian horses were basically the same species.”
