More support for the co-evolution theory, as reported in the Washington Post:
… A team of Swedish researchers compared the genomes of wolves and dogs and found that a big difference is dogs’ ability to easily digest starch. On their way from pack-hunting carnivore to fireside companion, dogs learned to desire — or at least live on — wheat, rice, barley, corn and potatoes.
As it turns out, the same thing happened to humans as they came out of the forest, invented agriculture and settled into diets rich in grains.
“I think it is a striking case of co-evolution,” said Erik Axelsson, a geneticist at Uppsala University. “The fact that we shared a similar environment in the last 10,000 years caused a similar adaptation. And the big change in the environment was the development of agriculture.”
The findings, published Wednesday in the journal Nature, support the hypothesis that dogs evolved from wolves who found a new food source in refuse on the outskirts of human settlements. Eventually they came to tolerate human contact and were brought into the household to be guards, workers and companions…
The change is at least partly the consequence of dogs having multiple copies of a gene for amylase, an enzyme made by the pancreas that is involved in the first step of starch digestion. Wolves have two copies; dogs have four to 30.
As it happens, amylase “gene duplication” is also a feature of human evolution. Humans carry more copies of the amylase gene than their primate ancestors…
Of course the ‘paleodiet’ enthusiasts will explain that increased amylase adaptation
causes autism was an unfortunate evolutionary misstep that’s condemned us, and our loyal companion animals, to degenerate into arthritic, wheezing couch potatoes on a rocky road to premature death. But at least we’ll have plenty of company on the journey.