Sahelanthropus tchadensis Hominid
Oldest Hominid Revisited, enter Toumai of Chad,
a.k.a., Sahelanthropus tchadensis


The July 11, 2002 issue of Nature's feature article describes Sahelanthropus tchadensis (nickname: Toumai, a new genus and species of the hominid clade. Based on associated fossils, the six specimens found in Chad in Central Africa are believed to be beween six and seven million years old. Because of both primitive and advanced morphological features, the fossils suggest more diversity in the human lineage than previously thought - rendering the antiquated concept of the "missing link" to further invalidity. Sahelanthropus has many traits indicative of hominids, such as smaller canines, and thicker tooth enamel than apes, and the point at the back of skull where neck muscles attach suggests that Toumaï walked upright. Many of these advanced features are missing from later fossils such as Australopithecus, but reappear in still later species that are classified in the genus Homo. The age of the fossils suggests than human and chimpanzee lineages diverged earlier than indicated by most molecular studies.

Brunet, M. et al. A new hominid from the Upper Miocene of Chad, Central Africa. Nature, 418, 145 - 151, (2002).
Vignaud, P. et al. Geology and palaeontology of the Upper Miocene Toros-Menalla hominid locality, Chad. Nature, 418, 152 - 155, (2002).