New Species of Human Ancestor Discovered in Africa is “Rosetta Stone” of Genus Homo

Archaeologists in South Africa have discovered a previously unknown species of human ancestor in the form of the 1.9 million-year-old partial skeletons of an adult female and a young male hidden deep in an underground cave outside Johannesburg.

Theyre thought to represent a key period of evolutionary transition between ape and man. The find is believed to be so important that the lead scientist behind their research has described the species dubbed Australopithecus sediba as potentially being the Rosetta Stone that unlocks our understanding of the genus Homo.

The find comes hot on the heels of the discovery of the remains of a 40,000-year-old human finger in Siberia, thought to belong to another previously unknown ancestor of Homo sapiens. The find suggests an undocumented species of man that lived alongside Neanderthals and early modern humans in parts of Asia as recently as 30,000 years ago.

Its represents the first new human ancestor identified since the discovery of Homo floresiensis, the strange hobbits who are thought to have inhabited the Indonesian island of Flores until 13,000 years ago.

Climbing Down From the Evolutionary Tree

Lee Berger, a palaeontologist at the University of Witwatersrand in Johannesburg, is the expert currently working hard to explain the story of Australopithecus sediba, which is represented by a pair of unlucky souls possibly mother and son who met their fate by falling together through a fissure in ground, before being carried a few metres by mud or water into a subterranean pool where they were gradually encased in rock.

Theyre believed to originate from the very foot of the human family tree, and are therefore thought to be of enormous importance to the study of mans evolution from primates.

These fossils give us an extraordinarily detailed look into a new chapter of human evolution, Berger told The Guardian, and provide a window into a critical period when hominids made the committed change from dependency on life in the trees to life on the ground. Sediba may very well be the Rosetta stone that unlocks our understanding of the genus Homo.

Some experts have voiced skepticism about the importance of Australopithecus sediba, however, because it shares such prominent anatomical features with both early humans from the genus Homo (long legs and a pelvis well adapted to walking upright), and their ancient predecessors the Australopithecines or southern apes (long arms like orang-utans).

The transition to Homo continues to be almost totally confusing, Donald Johanson of Arizona State University in Tempe an opponent of Bergers theory told Science magazine. Its Homo, he concluded.

The debate promises to continue.

DNA Evidence Points Finger in Direction of New Human Species

There was nothing so immediately dramatic about the remains found in Siberia specifically Denisova cave in the Altai mountains, a range that straddles Russia, Mongolia, China and Kazakhstan. The finger, which may have belonged to a young child and was recovered from a layer of rock in the cave dated to between 48,000 and 30,000 years ago is tiny, and offers no visible hint of unusual origins.

It was genetic testing that yielded results that left its researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany stunned. There was no match with the DNA profile of either Neanderthals or early modern humans. It is the first time a new type of human has been identified purely from DNA analysis.

It really looked like something I had never seen before. It was a sequence which is similar in some ways to humans, but still quite distinct.

It really looked like something I had never seen before, the Max Planck Institutes Johannes Krause told The Guardian. It was a sequence which is similar in some ways to humans, but still quite distinct.

Project leader Svante Pbo could hardly believe it when Krause called him to reveal the results of the test. It was absolutely amazing, I didnt believe him, Pbo said. I thought he was pulling my leg.

Krause and co are now concentrating on DNA from the nuclei of cells in the finger in a bid to figure out where the species fits into the human family tree, and also if it interbred at all with Neanderthals and modern humans.