Like agriculture, civilization was a global phenomenon, showing up independently in seven major locations scattered around the world during the several millennia after 3500 B.C.E. and in a number of other smaller expressions as well (see Map 2.1). In the long run of human history, these civilizations—small breakthroughs to a new way of life—gradually absorbed, overran, or displaced people practicing other ways of living. Over the next 5,000 years, civilization, as a unique kind of human community, gradually encompassed ever-larger numbers of people and extended over ever-larger territories, even as particular civilizations rose, fell, revived, and changed.