HOMINID FOSSILS FILL HUMAN ANCESTRY GAP / THE FINANCIAL TIMES ( HIGHLY RECOMMENDED READING )

Hominid fossils fill human ancestry gap


By Joseph Milton

Published: April 8 2010 15:11


Two well-preserved, 2m-year-old skeletons belonging to a previously unknown species of hominid have been unearthed from a cave in Malapa, South Africa.

Scientists believe the discovery helps to bridge a critical gap in the fossil record and boosts their understanding of humans’ early evolution.

The fossilised skeletons of an adult female and a juvenile male Australopithecus sediba were found in a cave in the “Cradle of Humankind” World Heritage Site near Johannesburg by Lee Berger, a palaeoanthropologist at the University of Witwatersrand.

Tests estimated the specimens at between 1.78m and 1.95m years old.

Prof Berger said they were two of the most complete skeletons of early hominids, adding that the state of preservation was “truly extraordinary”.

Although the newly discovered skeletons are incomplete, the bones are arranged almost as they would have been in life, and the material is so well preserved that scientists will be able to investigate the ageing process and disease.

Paul Dirks, a geoscientist, said the pair may have fallen or even climbed down a hole into a cave, perhaps in search of water, and been unable to climb out. Their bodies must have been inundated by a mudslide before they had fully decomposed, explaining the undisturbed arrangement of the bones.

The new species, described in the journal Science, displays a mixture of ape-like and human-like features. It has arms as long as an orang-utan’s but short, powerful hands, an advanced pelvis and long legs like a human, which would have enabled bipedal walking and possibly even running.

At 1.3 metres, they were taller than the famous 3m-year-old hominid “Lucy” found in 1974 but with very small heads relative to modern humans. Their brains were similar in size to Australopithecines but with a shape more like that of Homo – which gave rise to modern humans.
Prof Berger believes the mixture of human-like and ape-like features suggests the species would have been comfortable both on the ground and in trees.

He says the specimens could represent a transitional species between the more primitive Australopithecines and the more advanced members of Homo. However, he declined to describe the new species as a “missing link” between humans and apes.

A team of over 60 scientists is working on the findings at the site, which has yielded two more Australopithecus specimens since these were discovered.


Copyright The Financial Times Limited 2010.