The history of our species has occupied roughly the last 250,000 years, conventionally divided into three major phases, based on the kind of technology that was most widely practiced. The enormously long Paleolithic age, with its gathering and hunting way of life, accounts for 95 percent or more of the time that humans have occupied the planet. People utilizing a stone-age Paleolithic technology initially settled every major landmass on the earth and constructed the first human societies (see Chapter 1). Then beginning about 12,000 years ago with the first Agricultural Revolution, the domestication of plants and animals increasingly became the primary means of sustaining human life and societies. In giving rise to agricultural villages and chiefdoms, to pastoral communities depending on their herds of animals, and to state- and city-based civilizations, this agrarian way of life changed virtually everything and fundamentally reshaped human societies and their relationship to the natural order. Finally, around 1750 a quite sudden spurt in the rate of technological change, which we know as the Industrial Revolution, began to take hold. That vast increase in productivity, wealth, and human control over nature once again transformed almost every aspect of human life and gave rise to new kinds of societies that we call “modern.”
Here then, in a single paragraph, is the history of humankind—the Paleolithic era, the agricultural era, and, most recently and briefly, the modern industrial era. Clearly this is a big picture perspective, based on the notion that the human species as a whole has a history that transcends any of its particular and distinctive cultures. That perspective—known variously as planetary, global, or world history—has become increasingly prominent among those who study the past. Why should this be so?