New radiocarbon dates on American mastodon (Mammut americanum) fossils in Alaska and Yukon (eastern Beringia) suggest this species suffered local extinction tens of millennia before either human colonization – the earliest estimate of which is between 13,000 and 14,000 years ago – or the onset of climate changes at the end of the Ice Age about 10,000 years ago, when it was among 70 species of mammals to disappear in North America. Some...
