Ape-like creature is oldest known human ancestor

AN ape-like creature that lived seven million years ago was confirmed yesterday as the oldest known ancestor of humans.

New evidence is expected to settle the controversy over the fossil skull and jaw fragments unearthed in Chad in 2002.

It shows that the creature, named “Toomai” by scientists, had distinctly human features and may have walked upright.

Experts have been divided over whether the specimen, given the scientific classification Sahelanthropus tchadiensis, was an early human or an African ape.

One problem facing scientists is that the skull is badly squashed and damaged, making detailed examination difficult.

But yesterday researchers co-led by Toomai’s original discoverer, Dr Michel Brunet, from the University of Poitiers in France, described how they built a virtual re-construction of the skull.

The team used a high resolution computer tomography (CT) scan, similar to those employed in hospitals, to create the model.

It proved impossible to put the skull fragments together in a way that reproduced a head similar to that of a chimpanzee or gorilla.

But the scan was able to generate a faithful reconstruction resembling other hominids.

A number of features were revealed that Toomai shared with later hominids, including a “relatively vertical” face.

There was also evidence that Toomai walked upright on two legs - despite the fact that his species existed not long after the time when humans are thought to have diverged from apes.

Toomai’s eyes pointed forward perpendicular to the ground, yet his neck was relatively straight. A chimpanzee, spending most of its time on all fours, has to crane its neck up in order to look ahead.

The researchers wrote in the journal Nature: “The reconstruction confirms that S. tchadiensis is a hominid and is not more closely related to the African great apes.”

Further evidence of Toomai’s human pedigree emerged from an analysis of tooth and jaw fragments from other members of his species discovered in Chad.

They were described in Nature by a second team led by Dr Brunet.

The specimens provided additional features that confirmed the difference between S tchadiensis and African apes, said the researchers.