Bones from one of two skeletons discovered accidentally in 2008 by a 9-year-old boy near the vestiges of a South African cave might prove the direct predecessor to homo sapiens. A juvenile male and an adult female, dubbed Australopithecus sediba, lived approximately 2 million years ago. The word Australopithecus means "southern ape," and sediba means"wellspring" in the South African language Sotho. Researchers determined that the male was between 10 and 13 and the female in her late 20's or early 30's by dating the calcified sediments surrounding them with advanced uranium-lead dating techniques and a method called paleomagnetic dating, which measures how many times the Earth's magnetic field has reversed. (Charles Q. Choi, contributor to http://livescience.com/) The remains have both human and more primitive features that have led researchers to consider them an intermediary form between Australopithecus and Homo.
Lee Berger, a paleoanthropologist at the University of Witwatersrand in Johannesburg, South Africa, assembled a large team of experts to examine the skeletons. Berger explained, "The fossils demonstrate a surprisingly advanced but small brain, a very evolved hand with a long thumb like a human's, a very modern pelvis, but a foot and ankle shape never seen in any hominin species that combines features of both apes and humans in one anatomical package. You have things like a heel bone that's as primitive as a chimpanzee attached to the ankle bone that's as evolved as ours is. many very advanced features found in the brain and body and the earlier date make it possibly the best candidate ancestor for our genus, the genus Homo, more so than previous discoveries such as Homo habilis."
Anthropologists have injected a note of caution in drawing definite conclusions from these fossils Some who question whether Australopithecus sediba directly pre-dates human say sediba could have been one of many evolutionary experiments at the time, one that might have died out rather than creating the final link in the chain of human evolution. To learn more about this research, check the September 9th issue of the journal Science.