DNA study finds dog has been man's best friend for 33,000 years

The close relationship between humans and dogs began around 33,000 years ago, a recent DNA study has found. Domesticated dogs are most probably descendants of grey wolves that are believed to have made first contact with humans in south-east Asia.

The study, considered to be one of the largest of its kind, involved research into the genomes of 58 members of the canine breed. The study by professor Peter Savolainen of the Royal Institute of Technology, Solna, Sweden, and his colleagues researched grey wolves, Afghan hounds, Siberian huskies and assorted breeds from different parts of the world.

It was found that breeds originating from south-east Asia had a more diverse genetic history. They were also believed to be more closely related to grey wolves. Savolainen said the discovery suggests "an ancient origin of domestic dogs in south-east Asia 33,000 years ago".

He added: "The mild population bottleneck in dogs suggests dog domestication may have been a long process that started from a group of wolves that became loosely associated and scavenged with humans, before experiencing waves of selection for phenotypes (mutations) that gradually favoured stronger bonding with humans, a process called self-domestication."

The study outlines three stages of gradual domestication of dogs over the years. The first stage is believed to have roughly involved pre-domestic scavengers. The second stage consisted of non-breed, domesticated dogs and the final stage involved complete domestication and formation of breeds.

Researchers believe that around 15,000 years ago, dogs began migrating towards Africa and the Middle East, eventually reaching Europe some 10,000 years ago.

Although it is believed that the migration of dogs was a result of human movement, the very first migratory attempt of non-domesticated dogs from south-east Asia is believed to have been set in motion without human influence. Some researchers opine that the first move may have been prompted by environmental or climactic factors, like the threat of glaciers or shortage of food.

Although the study has revealed hitherto unknown facts about the history of dogs and their domestication, researchers believe that more in-depth research needs to be conducted to uncover the complete history of dogs. The study has been published in Cell Research.