4.06.2005

Fossil Supports Ape-to-Human Evolution

Evidence Shows Skull Is of Earliest Human - Study

from Reuters

LONDON - New evidence shows a 7 million year-old skull unearthed in Chad is the earliest member of the human family, scientists said Wednesday.

Controversy has surrounded the skull, dubbed "Toumai," since its discovery was first reported in 2002 by a team led by Michel Brunet of the University of Poitiers in France.

It was hailed as arguably the most important fossil discovery in living memory because it was thought to be an ancient ancestor of modern humans, although some scientists argued it was a fossil of a female ape.

But newly found remains of tooth and jaw fragments and a computer reconstruction of the skull, reported in the science journal Nature, suggest Toumai was more human than ape.

"Toumai is not a chimp. Toumai is not a gorilla," Brunet told Reuters. "It is perfectly clear Toumai is a hominid."

The first reliable records of hominids, members of the human family distinct from chimpanzees and other apes, suggest they did not appear until about 5 million years ago.

Brunet said Toumai probably lived not long after the two lineages split.

He and his team also believe the skull reconstruction suggests that Toumai, the name given to children in Chad born close to the dry season, might have been able to walk upright, which would mean bipedalism was present in the earliest known hominids.

Bipedalism is a crucial difference between apes and humans.

When the discovery of the skull was first reported, its unusual mixture of primitive and human-like features prompted scientists to believe it was the earliest member of the human family ever found which could shed new light on human evolution.

But some scientists doubted its human links because they thought the skull was too squashed to draw any conclusions. They also said its short face, small canine teeth and other characteristics were not evidence it was a direct ancestor of humans.

In a separate report in the journal, Brunet, Ponce de Leon and their colleagues said newly found dental and jaw fossils from the same time as Toumai also show differences between it and African apes.

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