America Under Ice: Who Walked Beside the Mammoths?

Twenty-one thousand years ago, three kilometers of ice sat where Chicago stands, and south of it people walked beside mammoths. Here is the evidence that proves it — scratches in Central Park, peat under the Bering Sea, footprints at White Sands. Two ice sheets the size of a continent, a sea level one hundred and twenty meters lower than today, and a grassland called the mammoth steppe running from Spain to the Yukon. Horses and camels were American animals before they vanished, and the rock record, ancient DNA and dated footprints show when the first people arrived. The ice drew the map of North America we live on, and the ground around Hudson Bay is still rising. Which piece of evidence convinced you most — the striations in Central Park, the tundra peat on the Bering seabed, or the White Sands footprints? Subscribe for more deep time documentaries. Chapters: 0:00 Ice over Chicago and New York 2:08 How the Laurentide Ice Sheet grew 3:31 Glacial scratches in Central Park 5:28 When the sea fell 120 meters 7:44 Tundra peat beneath the Bering Sea 9:13 The mammoth steppe, Spain to the Yukon 10:55 The horse is an American animal 12:44 George McJunkin and the Folsom bison 14:02 Clovis points and the Clovis First rule 15:52 Monte Verde in southern Chile 17:36 The kelp highway along the Pacific coast 19:15 Footprints in the Lake Otero mud 21:32 Dating seeds, pollen and quartz grains 23:10 What ancient genomes remember 25:05 Who walked at White Sands? 26:27 The ice dam above Lake Missoula 28:23 Bretz and the flood nobody believed 30:52 Thirty-five lost groups of giants 32:44 The last mammoths of St. Paul Island 34:09 Hudson Bay is still rising 35:31 The map the ice drew #IceAge #Documentary #Mammoth #Beringia Archive sources: • https://commons.wikimedia.org/wiki/Fi... (Ryan Chan, CC BY 3.0) • https://commons.wikimedia.org/wiki/Fi... (skinduptruk, CC BY 3.0) • https://commons.wikimedia.org/wiki/Fi... (MrAyrit, CC BY 3.0) • https://commons.wikimedia.org/wiki/Fi... (Sherp ET, CC BY 3.0) • https://commons.wikimedia.org/wiki/Fi... (Sander van Schie - De Verfilmer, CC BY 3.0) • https://commons.wikimedia.org/wiki/Fi... (r00t burn, CC BY 3.0) • https://commons.wikimedia.org/wiki/Fi... (Nature In 4K By: Paul King, CC BY 3.0)