Out of Africa
Nearly two hundred thousand years ago, modern humans, Homo sapiens, first emerged in the savannas of Africa. At that time, they were not the only human species on Earth; several other human species were scattered across different parts of the globe. In Europe, there were the robustly built Homo neanderthalensis, or Neanderthals. Meanwhile, the mysterious Denisovans lived in the caves of Central Asia, and in Southeast Asia, the diminutive Homo floresiensis survived. The great human family thus consisted of several different species. When Homo sapiens began their journey northward and eastward out of Africa, they encountered these other humans. In the icy caves of Europe, they met the Neanderthals—strong and physically powerful, but fewer in number. In the mountainous valleys of Central Asia, the sapiens confronted the Denisovans. This is not just a story of competition or conflict—it is also a story of remarkable mixing. Modern genetic research has revealed that encounters between these...