London: Dogs may have been domesticated by humans about 27,000 to 40,000 years ago, much earlier than previously thought, according to a new analysis of ancient wolf DNA.
Earlier genome-based estimates have suggested that the ancestors of modern-day dogs diverged from wolves no more than 16,000 years ago, after the last Ice Age.
The genome from an ancient specimen, which has been radiocarbon dated to 35,000 years ago, shows that the Taimyr wolf represents the most recent common ancestor of modern wolves and dogs.
“Dogs may have been domesticated much earlier than is generally believed,” said Love Dalen of the Swedish Museum of Natural History.
“The only other explanation is that there was a major divergence between two wolf populations at that time, and one of these populations subsequently gave rise to all modern wolves,” said Dalen.
Dalen considers this second explanation less likely, since it would require that the second wolf population subsequently became extinct in the wild.
“It is [still] possible that a population of wolves remained relatively untamed but tracked human groups to a large degree, for a long time,” said first author of the study Pontus Skoglund of Harvard Medical School and the Broad Institute.
The researchers made these discoveries based on a small piece of bone picked up during an expedition to the Taimyr Peninsula in Siberia.
Initially, they did not realise the bone fragment came from a wolf at all; this was only determined using a genetic test back in the laboratory.
But wolves are common on the Taimyr Peninsula, and the bone could have easily belonged to a modern-day wolf. On a hunch, the researchers decided to radiocarbon date the bone anyway.
It was only then that they realised what they had: a 35,000-year-old bone from an ancient Taimyr wolf.
The DNA evidence also shows that modern-day Siberian Huskies and Greenland sled dogs share an unusually large number of genes with the ancient Taimyr wolf.
“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,” Skoglund said.
To put that in perspective, “this wolf lived just a few thousand years after Neanderthals disappeared from Europe and modern humans started populating Europe and Asia,” Skoglund added.
The research was published in the journal Current Biology.
PTI
