A new study suggests that humans may have domesticated dogs 27,000 to 40,000 years ago, much earlier than previously believed. The study is based on an analysis of an ancient Siberian jaw fragment and shows that modern dogs diverged from their wolf ancestors 35,000 years ago. The Taimyr wolf, the most recent ancestor of wolves and modern dogs, lived a few thousand years after Neanderthals disappeared and modern humans spread throughout Asia and Europe.