Starchy diet may have transformed wolves to dogs

Even the most illustrious canine breeds can probably trace their heritage to junkyard dogs.

That’s the conclusion of a new study aimed at finding the genetic changes that transformed wild wolves into domesticated dogs. Dogs can digest carbohydrates better than wolves can, and gaining that ability may have been an important step in taming the animals, evolutionary geneticist Erik Axelsson of Uppsala University in Sweden and his colleagues report online January 23 in Nature. As humans settled into farming communities, wolves may have given up their meat-only diets to scavenge carbohydrate-rich food from garbage dumps. Animals that could best make use of the starchy food may gradually have morphed over generations into man’s best friend.

No one expected genes relating to digestion to be important for dog domestication, says Elaine Ostrander, chief of the National Human Genome Research Institute’s cancer genetics branch and an authority on dog genetics. Researchers previously thought that when wolves became domestic dogs, genes controlling behavior and the immune system must have changed.

The new study focuses on genetic differences between 60 dogs representing 14 breeds and 12 wolves from around the world. Those changes, the researchers reasoned, could identify genes that were important in separating dogs from wolves.