Researchers have discovered how Native Americans may have survived the last Ice Age after splitting from their Asian relatives 25,000 years ago.
Academics at Royal Holloway, University of London, and the Universities of Colorado and Utah have analysed fossils which revealed that the ancestors of Native Americans may have set up home in a region between Siberia and Alaska which contained woody plants that they could use to make fires. The discovery breaks new ground as until now no-one had any idea of where the native Americans spent the next 10,000 years before they appeared in Alaska and the rest of the North America.
Professor Scott Elias, from the Department of Geography at Royal Holloway said: "This work fills in a 10,000-year missing link in the story of the peopling of the New World. "
The findings, which are published in the journal Science, reveal that the ancestors of Native Americans may have lived on the Bering Land Bridge, which is now under the waters of the Bering and Chukchi Seas. The land bridge and some adjacent regions were not as dry as the rest of Beringia, and this central part of Beringia was covered in shrub tundra - the dominant vegetation in modern Arctic Alaska. It is dominated by dwarf willow and birch shrubs, mosses and lichens.
Professor Elias explained: "We believe that these ancestors survived on the shrub tundra of the Bering Land Bridge because this was the only region of the Arctic where any woody plants were growing. They needed the wood for fuel to make camp fires in this bitterly cold region of the world. They would have used dwarf shrub wood to get a small fire going, then placed large mammal bones on top of the fire, to ignite the fats inside the bones. Once burning, large leg bones of ice-age mammals would have burned for hours, keeping people alive through Arctic winter nights."
The academics made the discovery after analysing insect and plant fossils extracted from sediment cores taken from the ancient land bridge surface, which lies on the sea floor 50-60 metres below the water's surface.
Explore further: Soil nutrients may limit ability of plants to slow climate change