South Asia—the Indian subcontinent and certain adjacent lands and islands—is a vast region with great diversity in its climate, terrain, ecology, and other environmental features. Inevitably, then, it is impossible to set down generalizations that apply to the entire region. But one does hold up: there are no known fossil remains of the early hominids who most certainly are living there at least by about 450,000 B.C. (In fact, stone artifacts dating back as far as some 2,000,000 years have been found in the Pabbi Hills and Riwat in northern Pakistan, but these appear to be isolated instances.) Starting about 450,000 B.C., hominids and then archaic Homo sapiens living in parts of India produce a sequence of stone tools that, with several regional variants, tend to pass through much the same stages (in terms of types and techniques) as in other parts of the world during the Lower, Middle, and Upper Paleolithic periods. At some point, Homo sapiens appears in South Asia, but exactly who these first humans are—where they come from, their physical characteristics, etc.—is as yet unknown. By about 8000 B.C., the stone tools are also associated with rock paintings in caves and rock shelters, yet there are still no known remains of human beings. In the following millennia, communities begin to emerge throughout India, particularly in the northwest that will become Pakistan, and these gradually adopt or develop agriculture, domesticated animals, pottery, and the other elements of what is known as the Neolithic culture. The oldest human fossil remains known in South Asia are dated to about 3000 B.C., and by this time there is emerging in the Indus Valley the network of communities that will constitute the first true civilization of South Asia.
450,000–70,000B.C.: Hominids (presumably Homo erectus) apparently live in parts of the Indian subcontinent, for they leave their stone tools in many sites. During this time, these tools pass through much the same stages—crude hand-held choppers to more diverse and refined tools—as those made by hominids in other parts of the world during this period. Where these hominids came from is not known—possibly from Africa, possibly from the Near East; in any case, by the end of this period, the inhabitants of