Human ancestor's skeleton is 3-million-year-old

Scientists have found that a nearly complete skeleton of the Australopithecus fossil, named Little Foot, is around 3 million years old.

Australopithecus are the ape-man ancestors of humans. As many as nine different species of Australopithecus are believed to have existed from 2 to 4 million years ago in Africa.

An almost complete Australopithecus skeleton with skull embedded in hard, calcified sediment was discovered in an underground chamber of the Sterkfontein caves of Gauteng in 1997.

Ron Clarke, Stephen Motsumi and Nkwane Molefe of the University of the Witwatersrand, South Africa, began to carefully excavate this skeleton in order to expose it in place in the cave and to understand the ancient processes that contributed to its burial and preservation.

During the course of this excavation, it became clear that the skeleton had been subjected to ancient disturbance and breakage through partial collapse into a lower cavity and that calcareous flowstone had subsequently filled voids formed around the displaced bones.

Despite this fact being published, some other researchers dated the flowstones and claimed that such dates represent the age of the skeleton. This created a false impression that the skeleton is much younger than it actually is, according to the new study.
A French team of specialists in the study of limestone caves, Laurent Bruxelles, Richard Maire and Richard Ortega, together with Clarke and Dominic Stratford of Wits University, have now shown that the dated flowstones filled voids formed by ancient erosion and collapse and that the skeleton is therefore older, probably considerably older, than the dated flowstones.

Little Foot is probably around 3 million years old, and not the 2.2 million years that has been wrongly claimed by other researchers, the study authors said.

The skeleton has been entirely excavated from the cave and the skull, arms, legs, pelvis and other bones have been largely cleaned of encasing rock.

Clarke has concluded from study of the skull that it belongs to Australopithecus prometheus, a species named by Professor Raymond Dart in 1948 on fragmentary ape-man fossils from Makapansgat in what is now Limpopo Province.The study was published in the Journal of Human Evolution.