http://www.theguardian.com/lifeandstyle/2015/may/21/dogs-may-have-lived-with-humans-30000-yearsDomestic dogs may have a pedigree that dates back almost 40,000 years to when modern humans started colonising Europe and Asia, new research has shown. Previous studies suggested that the ancestors of modern-day dogs diverged from wolves no more than 16,000 years ago, after the last ice age. But new evidence – from a small bone found in a remote region of Siberia – indicates that the special relationship between man and dog is much older. Analysis of the 35,000-year-old rib bone fragment from the Taimyr peninsula showed that it belonged to the most recent common ancestor of modern wolves and dogs. DNA from the bone also allowed scientists to “recalibrate” the genetic clock used to estimate rates of evolutionary change. This is based on the rate at which species produce new mutations.
The canine rate turned out to be slower than had previously been thought, pushing back the likely point in time when wolves and dogs diverged. In addition, modern Siberian huskies and Greenland sled dogs were found to share an unusually large number of genes with the ancient Taimyr wolf. Researcher Dr Love Dalen, from the Swedish Museum of Natural History, said: “Dogs may have been domesticated much earlier than is generally believed.” The findings are reported in the journal Current Biology. In their paper, the scientists point out that there have been several reports of dog-like “canids” – the family that includes wolves and domestic dogs – up to 36,000 years old in the fossil record. There was also evidence that domesticated dogs may have accompanied early humans migrating from Asia to North America, possibly as long as 30,000 years ago.
The researchers wrote: “Our results provide direct evidence for a longer timescale for the divergence of the dog and wolf lineages than previously assumed, and thus suggest that dogs may have originated much earlier than commonly accepted … “The initial divergence between the ancestors of dogs and grey wolves would not necessarily have had to coincide with domestication in the sense of selective breeding, since this human-mediated process could have occurred later or over an extended period of time.” Co-author Dr Pontus Skoglund, from Harvard Medical School, said: “The power of DNA can provide direct evidence that a Siberian husky you see walking down the street shares ancestry with a wolf that roamed northern Siberia 35,000 years ago. This wolf lived just a few thousand years after Neanderthals disappeared from Europe and modern humans started populating Europe and Asia.”
