About 74,000 years ago on the island of Sumatra, Indonesia, the largest volcanic event over the last two million years, 5,000 times larger than the Mount St. Helen's eruption in the 1980s, ushered in a worldwide "volcanic winter" that lasted up to ten years followed by a 1,000 year-long cooling of the Earth's surface.While how close humanity got to extinction is unknown, surviving Homo sapiens in Africa were said to have survived by developing new strategies that eventually enabled them to re-expand and populate Asia 60,000 years ago in a single, rapid wave along the Indian Ocean coastline.