National Geographic : 2010 Jun
0mi 400 0km 400 SOUTH AFRICA BOTSWANA ZIMB. NAMIBIA Johannesburg Malapa PHOTO: BRETT ELOFF. NGM MAPS ARCHAEOLOGY A Revealing Relative Finds at Malapa cave in South Africa may provide a big piece to an unsolved puzzle of human evolution. Paleoanthropologist Lee Berger of the University of the Witwatersrand and his team discovered two fossil skeletons of a previously unknown human ancestor there, embedded in limestone almost two million years old. The new species, Australopithecus sediba, lived when human ancestors were evolving from more primitive australopiths toward our direct ancestor, Homo erectus. The small brain and long arms of A. sediba are like those of an australopith, but the shapes of its teeth and brain case are like those of Homo. Until now the bones of early hominin species known from this period were few and fragmentary. "The origin of Homo is the question of the decade," says Susan Antón, a physical anthropologist at New York University. "Anyone working on that question will have to take these new fossils into account." Berger hopes for more---that the fossils solve the puzzle once and for all. ---Christopher P. Sloan This juvenile skull from Malapa cave emerged once the surrounding limestone was teased away. Malapa is part of an extensive system of fossil-rich caves near Johannesburg, South Africa.