Ancient DNA discovered by researchers is revealing the history of horse domestication for the first time.
A team of researchers examined the DNA of 29 horse bones, which were found in the Siberian permafrost - dating from 16,000 and 43,000 years ago. They preceded to compare the DNA found in the bones to the DNA from five modern domesticated breeds of horses, according to a news release.
By comparing the genes from ancient horses to the domesticated ones living today researchers were able to learn how exactly the animal helped revolutionize trade, warfare, the movement of people, the transmission of ideas and the development of continent-sized empires (such as the Scythians 2,500 years ago in what is now Iran).
The study was tricky to complete because there are very few wild horses left in the world since most horses today are domesticated. Przewalski's horses from Mongolia are the only surviving wild horse population, descending from a mere 13 individuals. The wild horses are preserved through a massive conservation effort.
Genes from the Przewalski horses were also analyzed in the study as a baseline for the ancient horses.
The genes in the ancient horses allowed the researchers to identify the transformation of specific signatures in the genes over time when they began to be increasingly domesticated.
"This confirms previous findings that wild horses were used to restock the population of domesticated horses during the domestication process," Mikkel Schubert, co-leading author of the study said in the release.
"However, as we sequenced whole genomes, we can estimate how much of the modern horse genome has been contributed through this process. Our estimate suggests that at least 13 percent, and potentially up to as much as 60 percent, of the modern horse genome has been acquired by restocking from the extinct wild population. That we identified the population that contributed to this process demonstrates that it is possible to identify the ancestral genetic sources that ultimately gave rise to our domesticated horses."
