New ancient ancestors?

According to Friday’s Independent a series of well preserved fossilised skeletons found in South Africa and identified are a new ancestral species of hominid that could have been the direct ancestor of humans.

The species lived about 1.9 million years ago, walked on two legs and shared many other human features, but it also retained clear ape-like traits such as very long. Researchers claimed yesterday that the species, named Australopithecus sediba, possesses such a mosaic combination of ape-like and human-like traits that it might belong to the group of "apemen" who evolved into the Homo genus – the human family.

The Homo genus came into existence around two million years ago, possibly evolving from the Australopithecines, that lived in sub-Saharan Africa before this period. However, the paucity of the fossil record for this period in human history has cast doubt on exactly how the ape-to-human transition occurred. Now, however, with the discovery of four skeletons belonging to Australopithecus sediba scientists believe they may have found the immediate ancestor of all subsequent species of Homo, from the primitive species such as Homo erectus and Homo habilis, to the anatomically modern Homo sapiens.

The scientists discovered the first skeleton in 2008 from a pit-like excavation at Malapa, near "I thought it was an antelope fossil but as I walked over to him, five metres away I realised he had a hominid clavicle [collarbone] sticking out of the rock. When I got to the rock and turned it over there was a hominid mandible and canine sticking out of the back," said Professor Lee Berger of the University of Witwatersand in Johannesburg, the leader of the study.


Although the species has very long forearms like tree-dwelling apes, its hands and fingers are short and powerful, more like those of humans. They stood about 1.3m tall and their pelvis indicates they could walk and run easily on two legs. They had small heads and their brain was less than a third of the size of modern human brains. Their legs were long, but the anatomy of the foot was "primitive", the scientists said.

The remarkable preservation of the fossils occurred because the creatures had probably died after falling or climbing down a vertical "death shaft" leading to the underground cave system. Within days of their death, a sudden rainstorm and mudflow probably washed their bodies – along with the bones of sabre-toothed cats, hyenas, wild dogs and horses – into a deeper, waterlogged recess where they were quickly encased in calcified rock.

The proportion of creatures that get fossilised after death is tiny so to find any hominid remains is good fortune. Fascinating stuff!