Modern horse breeds are the product of some phenomenal mixes of horses from various regions across the globe. Geneticists know this interregional mixing occurred many centuries ago, but how do genes from a horse in Western Europe during the Biblical era become blended with horses residing in Eastern Asia?

Simple answer: The Silk Roads.

“The Silk Roads had been shown to have influenced the genetic structure of humans in eastern Eurasia, so I was curious about how far the Silk Roads played a role in horse movement as well,” said Vera Warmuth, PhD, researcher in the department of zoology at the University of Cambridge in the U.K.

The “Silk Roads” were a 4,000-mile series of connecting trade routes linking the Mediterranean Sea to southeast China starting in about 200 BC. They paved the way for the lucrative Chinese silk trade, but they also opened the door to extensive intercultural and educational exchanges. And, Warmuth said, they opened the door to horse trading