Toumaï tooth trouble

Palaeontologist Michel Brunet has dismissed claims that a tooth was stuck in the wrong place during reconstruction of Toumaï, a fossilised skull some 7 million years old, recognised as belonging to the oldest known human ancestor.

The assertions appeared in the South African Journal of Science (SAJS) in an article by Alain Beauvilain, a geographer at Paris-10 University, and orthodontist Yves Le Guellec, which purports to reveal further details about the fossils. It alleges, with photographs, that a molar that should have fitted the left side of Toumaï's lower jaw had been erroneously placed in a gap on the right side.

Professor Beauvilain was a member of the team headed by Professor Brunet that uncovered the skull and related fragments from different individuals in the Djurab desert of northern Chad in July 2001. The discovery of Toumaï, Sahelanthropus tchadensis , was published in Nature in July 2002 in a paper by Professor Brunet, co-signed by 37 other scientists, including Professor Beauvilain. The article, anonymously peer-reviewed by five independent experts, proclaimed the skull, dated at nearer 7 million than 6 million years old, was from "the earliest known hominid".

Controversy over Toumaï erupted three months later when Nature published a dissenting article that claimed the skull was not from a hominid, but probably from an ape. This was signed by Milford H. Wolpoff of Michigan University, Brigitte Senut of France's national Natural History Museum, Martin Pickford of the Coll ge de France and John Hawks of the University of Wisconsin. Professor Brunet vigorously denied their allegations.

Last week Professor Brunet told The Times Higher by email from the US: "At this point, I can tell you that the tooth in question is certainly a lower right (molar) and not a left one. The SAJS article is much more polemical than scientific. It is astonishing that a journal would allow publication of statements with no scientific basis. It is pathetic that this should be used by the authors for a campaign of disinformation aimed at discrediting my team scientifically."