Eastern Africa may very well be the birthplace of humanity. 1 Some of the earliest predecessors of Homo sapiens lived around the lakes and in the lush, game-filled savannas of the Great Rift Valley. During the late 1950s and 1960s, the remains of Zinjanthropus boisei and Homo habilis were discovered at Olduvai Gorge in northern Tanzania. These two species lived during the Lower Pleistocene epoch, between three million and one million years ago. More recently, a probable ancestor of these protohumans was uncovered near Lake Turkana in Kenya. Pioneered by the Leakey family of prehistorians, the search continues for still older evolutionary progenitors.