In a separate paper, a team including Brunet and Christoph
Zollikofer of the University of Zurich in Switzerland, presents a 3D
computer reconstruction of the skull, which had been badly distorted
in the ground.
The team has essentially "unmangled" the skull, and the
reconstruction appears to confirm that tchadensis shared key
features with later hominids.
In addition, the position of the foramen magnum - the hole where
the spinal cord enters - is similar to that in humans but not apes.
This suggests Toumaļ was bipedal; the creature walked upright like
"We performed a virtual reconstruction because the skull is
heavily mineralised and distorted. It is impossible to do one by
physical means," Professor Zollikofer said. "[The find] is
absolutely unique for several reasons. First, because of its age.
Then because of its geographical location. Third, because it is
Martin Pickford, of the National Museum of Natural History in
Paris, is one of those scientists unconvinced by arguments that
Toumaļ is a hominid.
"What we're saying is that it is an ape-like animal. It may well
have given rise to bipedal hominids, but it's not yet a bipedal
hominid," Dr Pickford said.
Professor Zollikofer commented: "I would say most of the
disagreement over the fossil came from the fact that it is
distorted, so it is quite difficult to recognise the diagnostic
If Toumaļ really does belong on the human branch of the
evolutionary tree, its discovery calls into question certain
assumptions about our prehistory. The fossils were found some
2,500km (1,500 miles) west of the African Great Rift Valley -
traditionally seen as humankind's ancestral home due to the wealth
of hominid fossils that have been discovered there.
The discovery of tchadensis implies early hominids ranged
far wider from East Africa, and far earlier, than previously
thought. It also suggests that hominids evolved quickly when they
set off on their own evolutionary path.