National Geographic : 1997 Feb
Evolution headquarters Even after decades of excavation at Olduvai Gorge (above), Rutgers University paleoanthropologist Robert Blumenschine says, "there's no end to the treasures that can be found." Louis and Mary Leakey's pioneering work established Olduvai as the most famous of early prehistoric sites. With an international team (below), Blumenschine continues excavations here. Sediments offer him clues to the rise and fall of lakes and springs. Bone fragments gnawed by teeth or gouged by tools help him reconstruct ancient relationships among predators, scavengers, and prey.