People were keeping dogs as pets in North America around 1,000 years earlier than we previously thought. By re-analyzing bones of dogs first dug up in the 1960s, scientists have been able to push back the history of domestic dogs in the New World.
The analysis is part of a new study that is currently available to read as a preprint on bioRxiv, with the full study expected to be released later this year. The team of researchers have re-tested three ancient dog skeletons that were unearthed in what is now Illinois, and while originally these were dated to around 9,500 years old, using new techniques they oldest was found to be at least 10,190 years old, making it the oldest domestic dog remains discovered in the Americas.
What is curious about the dates of these bones – despite the fact that they are a thousand years older than we thought – is simply how young they are when put into the context of the peopling of the Americas.
While the exact origin of the domestic dog is somewhat unclear, the earliest evidence for the first undisputed dog dates to the remains of a 14,200-year-old canine discovered in Germany. This means that in Eurasia, people were taming wolves at least 4,000 years earlier than in the Americas, although there are some contentious fossils that could push this event back even further.
It is thought that humans first moved onto the Beringia land bridge that connected eastern Russia and Alaska some 36,000 years ago, where they became relatively isolated from those left in Siberia and became a distinct group now known as the Ancient Beringians.
They likely lived on this bridge for thousands of years, during which time there was still genetic flow and movement with what is now Russia, until the massive ice sheet that was covering North America opened up and allowed a small band of people to cross over into the Americas. Yet there is apparently no evidence that these ancient Siberian people brought dogs with them to the new world.
Why this was the case is still not known, although it could be a simple bias. These early humans might not have had particularly strong bonds with their working animals, and so may not have buried them limited the chance that they would be preserved for us to find. Or, it could suggest that they were brought over at a later date as other groups migrated from Asia.
[H/T: New Scientist]