Dogs Evolved by Eating Our Waste

There may be a reason that your dog somehow--inevitably--manages to get into your trash and drag it around the house. New research of the dog genome has linked widespread dog domestication to the emergence of agriculture--and our trash.

The study, published in the journal Nature, revealed that humans didn't first bring dogs to settlements. More than likely, 12,000 years ago we attracted the animals with our heaps of garbage. The research examined dog DNA, noting that it revealed numerous genes associated in starch metabolism, compared with wolves. The study seems to agree with the theory that the domesticated dog emerged from wolves that were able to scavenge and digest the food waste of early farmers.

Erik Axelsson and his colleagues examined the DNA of more than 50 modern dogs. The breeds of the dogs ranged from the cocker spaniel to the German shepherd, giving the scientists a broad range to work with. They then compared the genetic information with those of 12 wolves.  

In order to find differences, they scanned the DNA sequences of the wolves and dogs. Locations of major difference between the canids would likely contain genes that were important in the rise of the domestic dog. Overall, the team found 36 regions, carrying a little over a hundred genes. The two major functional categories, though, were genes involved in brain development and starch metabolism.

While the difference in brain activity is certainly crucial to the modern dog, it's the ability to metabolize starch that really creates our favorite canine companion. It allowed ancient dogs to scavenge discarded wheat, and brought them closer to humans. The next time you see your dog rooting through the trash, don't punish him--just accept that it's part of his nature.