human prehistory: weathering the storm
A Not-So-Hospitable Planet
Around 20,000 years ago, the world was suffering through the Last Ice Age. For millennia, temperatures hovered around 15 degrees Fahrenheit below what they are today. Mile thick glaciers covered much of North America, Europe and Asia. Survival was difficult even outside of the ice-covered regions because it was extremely dry. The few areas our ancestors found refuge in are shown on this map in green.
Barriers Separate Human Groups
Against all odds people found ways to survive in severe conditions, moving as far north as Siberia. But groups of humans became separated from one another by barriers of ice and desert, setting the stage for linguistic and cultural differentiation.
Journey to the Americas
The Ice Age not only created barriers; it also created bridges. With so much water locked up in ice, sea levels dropped, exposing land and connecting Siberia and Alaska. A few people in Siberia took advantage of this bridge, moving into present day Alaska and, later, down into other parts North America. Maybe they followed migrating herds of big game. Or maybe they traveled in small boats down the Pacific coast. Or maybe they did both.
In just a short time, humans from a small region of Africa had populated all of the continents except for Antarctica. Some populations around at the beginning of the Ice Age didn't survive. Others made it through, but ended up cut off from all other humans.
New Languages, Cultural Innovations
Scattered around the world, small, isolated populations became linguistically, culturally, and genetically distinct from one another. By 10,000 years ago the ancestors of today's languages were emerging. Cultural innovations during this period would eventually help a few populations expand dramatically over the next several thousand years.