Humans and dogs have lived side by side for times immemorial. However, the domesticated creatures that stay with us under one roof are far different from their ancestral wolves. Besides their shapes and sizes, they have a lot of differences in their DNA too, for instance, their ability to digest a wide range of foods.

New genetic evidence now hints that dogs have been enjoying human food scraps ever since they were domesticated. Scientists are of the view that dogs in the form of ancestral wolves were living with humans for over 15,000 years and scavenged food scraps from hunters, possibly sprucing up the bones following the kills. Modern dogs, on the other hand, have the ability to digest starch more efficiently compared to wolves, which are purely carnivores.

Researchers from Romania, France, Sweden and Russia studied the DNA from the bones and teeth of 13 ancient dogs found across Asia and Europe, dating back to almost 15,000 years. The team found a common gene in all the samples that showed the ability of the dog to digest starch products.

This goes back to the time when hunters adopted agriculture too. Dr Morgane Ollivier from France-based ENS de Lyon, said that the samples obtained were associated to agricultural development in the early days of farming. It's a great illustration of parallel evolution of the human race, he told BBC News.

Scientists are now trying to find out the way dogs became tamed from wolves. Some say that ancient hunters used wolves as companions during hunting as guards and eventually trained them while others are of the view that domestication began later, when wolves started stealing leftover foods and began living with humans.

The study, published in the journal Royal Society of Open Science, adds weight to the view that dogs were domesticated when they moved into human settlements to steal food and eventually developed the ability to live on a human diet.