New fossil dates show our ancient cousins disappeared 40,000 years ago. The Neanderthals died out about 10,000 years earlier than previously thought, new fossil dating suggests, adding to evidence that the arrival of modern humans in Europe pushed our ancient Stone Age cousins into extinction. (Read "Last of the Neanderthals" in National Geographic magazine.) Neanderthals' mysterious disappearance from the fossil record has long puzzled scholars who wondered whether the species went extinct on its own or was helped on its way out by Europe's first modern human migrants. "When did the Neanderthals disappear, and why?" says Tom Higham of the...