The ancestor of all living horses, donkeys and zebras lived about four million years ago, suggests a new study, pushing back the confirmed age of the horse's progenitor by two million years.
The discovery comes from the genetic analysis of a 700,000-year old horse fossil trapped in the Canadian permafrost. That's hundreds of thousands of years older than any genome ever sequenced before.
Among other insights, the sequence supports the often-debated view that the Przewalski's horse, native to the Mongolian steppes, is the last living population of truly wild horses in the world.
And while the new study offers an intriguing look into the history of horses and how they have changed over millenia, the research also opens up the possibility of getting a much longer view into the evolution of all sorts of species, including people.
"This really shows that you can go much further back in time and do genomics than people previously thought," said Eske Willerslev, an evolutionary geneticist at the University of Copenhagen. "Suddenly, that means that we can potentially go back and do the genome for precursors to Neanderthals. Maybe there's potential for getting the genome of Homo erectus. From a scientific standpoint, this is really great."