Old Dogs Teach a New Lesson About Canine Origins

摘要

The story of dogs began thousands of years ago, when gray wolves began sidling out of the shadows and into the company of humans. There's little argument about that scenario-but plenty about when and where it took place, with the leading theories suggesting dogs were domesticated either in the Middle East or in East Asia. A study on page 871 draws on a new source of evidence, DNA from the fossils of ancient dogs and wolves, and comes to a third conclusion: Dogs originated in Europe, from a now-extinct branch of gray wolves. The dogfight goes on. Based on the new study, "you will be hard-pressed to come up with a narrative about how dogs were not domesticated in Europe," says Greger Larson, an evolutionary biologist at the University of Durham in the United Kingdom. But some fans of the East Asia theory argue that the DNA examined, from cell organelles called mitochondria, cannot tell the whole story and that the analysis may be skewed because the ancient samples are primarily from Europe. "Critical observers will need more than mitochondrial DNA to be convinced," says Stephen O'Brien, a geneticist at St. Petersburg State University in Russia, who says he is in neither dog origin camp.