Communication in The Americas and their Influence

The Americas were first settled from Asia by successive waves of migrants who crossed the Bering Sea from Siberia to Alaska during the last Ice Age using a land bridge, the frozen sea, and possibly open boats. Estimates as to when this began range from twenty thousand to one hundred thousand years ago. By 8000 B.C.E. settlements had reached the southern tip of South America. The new arrivals came as hunter-gatherers, but over the millennia many adopted agriculture and a few groups built civilizations comparable to what had developed earlier in ancient Mesopotamia, Egypt, and the Indus Valley.