Today, every significant landmass on earth is occupied by human beings, but it was not always so. A mere half million years ago our species did not exist, and only 100,000 years ago that species was limited to Africa and numbered, some scholars believe, fewer than 10,000 individuals. These ancient ancestors of ours, rather small in stature and not fast on foot, were armed with a very limited technology of stone tools with which to confront the multiple dangers of the natural world. But then, in perhaps the most amazing tale in all of human history, they moved from this very modest and geographically limited role in the scheme of things to a worldwide and increasingly dominant presence. What kinds of societies, technologies, and understandings of the world accompanied, and perhaps facilitated, this globalization of humankind?

The phase of human history during which these initial migrations took place is known to scholars as the Paleolithic era. The word “Paleolithic” literally means the “old stone age,” but it refers more generally to a food-collecting or gathering, hunting, and fishing way of life, before agriculture allowed people to grow food or raise animals deliberately. Paleolithic cultures operated within natural ecosystems, while creatively manipulating the productive capacities of those systems to sustain individual lives and societies. Lasting until roughly 11,000 years ago, and in many places much longer, the Paleolithic era represents over 95 percent of the time that human beings have inhabited the earth, although it accounts for only about 12 percent of the total number of people who have lived on the planet. It was during this time that Homo sapiens colonized the world, making themselves at home in every environmental setting, from the frigid Arctic to the rain forests of Central Africa and Brazil, in mountains, deserts, and plains. It was an amazing achievement, accomplished by no other large species. Accompanying this global migration were slow changes in the technological tool kits of early humankind as well as early attempts to impose meaning on the world through art, ritual, religion, and stories. Although often neglected by historians and history textbooks, this long period of the human experience merits greater attention and is the focus of the initial sections of Chapter 1.