Some two-million-year-old fossils from South Africa could reshuffle the family tree of early human ancestors. Two fossils from a recently discovered hominin species called Australopithecus sediba show human-like features typically seen in later fossils.
Lee Berger at the University of the Witwatersrand in Johannesburg, South Africa, and his team first discovered the remains (pictured) in a cave near Johannesburg in 2008. Now, a closer look at two A. sediba individuals, a boy and a woman, uncovers an assortment of primitive and modern traits, such as a small brain with a front portion shaped like a human's. A. sediba's squat pelvis looks modern, casting doubt on the idea that this form evolved to give birth to large-brained babies. Its long, ape-like arms bear human-like hands with long thumbs adapted for gripping. A. sediba walked on two feet; its ankle resembles a human's, but its heel and shin bones look like a chimpanzee's.
Berger's team says that A. sediba could be the direct ancestor of Homo erectus, and so of modern humans. Alternatively, the fossils may mark a late-surviving form of Australopithecus that later went extinct.
Rights and permissions
About this article
Cite this article
A mixture of old and new. Nature 477, 252 (2011). https://doi.org/10.1038/477252a
Published:
Issue Date:
DOI: https://doi.org/10.1038/477252a