Dogs are so in tune with humans now that they can tell if their owners are happy or angry. That close relationship that has existed since before they helped early humans take down mammoths. But the exactly how long canines have provided companionship just got a revision: Instead of pinning domestication at about 11,000 to 16,000 years ago, new genetic evidence shows that man’s best friend may have split from wolves 27,000 to 40,000 years ago.
The new date comes from researchers who analyzed a bone found on Siberia’s Taimyr Peninsula, reports Eryn Brown for The Los Angeles Times. The animal lived 35,000 years ago and was a type of ancient wolf, they determined. Brown reports:
Examining the animal's mitochondrial and nuclear DNA and comparing them to genomes of modern wolves and dogs, the team surmised that there must have been a three-way split among the Taimyr, dog and wolf lineages.
That three-way split happened around the same time, and the Taimyr represents the most recent common ancestor of wolfs and dogs. Later, the Taimyr wolf lineage became extinct. The researchers published their findings in Current Biology.
The original date range put dogs’ domestication around the time humans started agriculture, reports Pallab Ghosh for BBC News. He ask a researcher involved in the new study, Love Dalén of the Swedish Museum of Natural History in Stockholm, what the new date means for how the bond between humans and dogs formed.
"One scenario is that wolves started following humans around and domesticated themselves," Dalén told BBC News. "Another is that early humans simply caught wolf cubs and kept them as pets and this gradually led to these wild wolves being domesticated. If this model is correct then dogs were domesticated by hunter gatherers that led a fairly nomadic lifestyle."
Ghosh also spoke to Greger Larsen of Oxford University, who is studying the origin of dogs by analyzing skulls and teeth from around the world. Larsen explained how previous research may have missed this earlier date in dogs’ evolution:
Larsen says that the archaeological evidence is biased towards the later stages of dog evolution because dogs probably didn't start looking like dogs as we know them until relatively recently.
However, he believes the process was a continuous one, so much so that he has banned the use of the words "dog" and "wolf" in his lab.
Further evidence of that muddling remains in modern day Siberian Huskies and Greenland sled dogs. They share a large number of genes with the extinct Taimyr wolves, because that ancient lineage apparently interbred with more domesticated dogs to give rise to those Arctic breeds. The line between wolves and dogs was also blurred throughout the domestication process as animals from the wolf and dog lineages occasionally bred (something they still do today).
Still, despite this mixing with their wild cousins, dogs on the whole remain considerably more domesticated than cats. But most people could have guessed that fact, even without science to back them up.