Washington, October 18 : The world's first known dog was a large, toothy canine that subsisted on a diet of horse, musk ox and reindeer 31,700 years ago, according to a new study.
The remains of the prehistoric dog were excavated at Goyet Cave in Belgium.
This discovery can push back the date for the earliest dog by 17,700 years, as the second oldest known dog, found in Russia, dates to 14,000 years ago.
The researchers say that if Paleolithic dogs still existed as a breed, they would surely win best in show for strength and biting ability.
"The most remarkable difference between these dogs and recent dog breeds is the size of the teeth," Discovery News quoted lead author Mietje Germonpre as saying.
The researchers compare their tooth size more to wolves than dogs.
"In shape, the Paleolithic dogs most resemble the Siberian husky, but in size, however, they were somewhat larger, probably comparable to large shepherd dogs," said Germonpre, a paleontologist at the Royal Belgian Institute of Natural Sciences.
"The Paleolithic dogs had wider and shorter snouts and relatively wider brain cases than fossil and recent wolves," said Germonpre, adding that their skulls were also somewhat smaller than those of wolves.
The researchers revealed that analyses of the animals' bones suggested that they consumed horse, musk ox and reindeer, but not fish or seafood.
Their study also suggests that the Aurignacian people of Europe from the Upper Paleolithic period first domesticated dogs, something that is characterised by fine jewellery and tools that were often decorated with depictions of big game animals.
"I think it is possible that the dogs were used for tracking, hunting, and transport of game. Transport could have been organized using the dogs as pack animals. Furthermore, the dogs could have been kept for their fur or meat, as pets, or as an animal with ritual connotation," said Germonpre.
University of Victoria anthropologist Susan Crockford, however, is not convinced the Aurignacians domesticated dogs.
She instead suspects that dogs might have undergone "self-domestication" from wolves more than once over history, which could explain why the animals appear and then seemingly disappear from the archaeological record.
Germonpre does not dismiss Crockford's theory, and instead describes it as "a very interesting model".
She hopes that more information would be gained in future about the very early canines.
An extensive study on their teeth and jaws is already in the works, she has revealed.
A research article on the discovery has been published in the Journal of Archaeological Science.