Even if Fido prefers steak, his ability to digest gruel instead may provide a key clue to dogs’ evolutionary transformation from wolves, according to research published today in the journal Nature.
Scientists who compared the dog’s full gene sequence with that of wolves found about 36 regions that may have been changed during domestication. Among genes affected were three that play a role in how the animals digest starch, the study showed.
The research adds another facet to the debate over how dogs morphed from adversary to ally some 10,000 years or more ago. Tweaks in the starch-digestion genes may be evidence that dogs’ carnivorous ancestors adapted to scavenge for scraps from waste dumps outside the camps of humans who were just settling down to grow crops, said Erik Axelsson, an assistant professor of evolutionary genetics at Sweden’s Uppsala University.
“It must have been crucial for early dogs to be able to thrive on a diet that was a lot more rich in starch,” Axelsson, one of the study’s authors, said in a telephone interview. “It wasn’t so much a question of whether I like to eat this porridge or root or whatever it could have been, but that I need to eat it.”
There are parallels in the changes that occurred in humans themselves as their bodies adapted to better digest the new food source, according to Axelsson. The development of agriculture “may have been the factor that got the domestication process started,” he said.
The researchers used pooled DNA from 12 wolves and 60 dogs from 14 different breeds for the study.