Toumai is older than 7 million years
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Updated June 01, 2013
Toumai is the nickname of a fossil skull, virtually complete primate, discovered by Chad Ahounta Djimdoumalbaye July 19, 2001, in the desert in northern Chad Djurab site TM266.
This new hominid is the oldest known representative of the human lineage. It led to the definition of a new species, Sahelanthropus tchadensis, probably very close to the chimpanzee divergence hominins (the hominines are the hominid line that owns the human race and extinct species such as Australopithecus).
The age of the land that has delivered the fossil could be determined by the method of beryllium 10 / beryllium 9 an absolute dating method that has yielded an age between 6.8 and 7.2 million years.
Dad Scientific Toumai is French, Michel Brunet.
This paleontologist had already discovered in 1995 the jaw of Abel, the first Australopithecus unearthed in West Africa. Toumai was about 1 meter long and weighed nearly 35 kg. Toumai is a male.
It is her strong ridge supraorbital argues for this claim, but Brigitte Senut, paleontologist of hominoids and hominines Miocene and Pliocene, notes that "the supraorbital rim is not a conventional character of sexual dimorphism. Toumai lived in the woods near a lake or near a river."
According to the fossil trees, animal remains and traces of water in the desert the hottest African, Tumaï, there are 6 million years, lived in a garden (rivers, trees, elephants, birds). The heart of Africa, is now an arid desert, is the cradle of humanity. "Alain de Beauvilain" Tumaï, the human adventure."
Toumai means "hope of life" language or Gorane Tubu. This name was chosen by the President of the Republic of Chad.
Image: Toumaï: fossil skull of 7 million years, almost complete, discovered July 19, 2001, in the desert in northern Chad Djurab site TM266.
Fossils discovered in Chad
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Over a dozen kilometers between sites KT 12 and KT 40, all at the foot of an ancient lake cord, on lots of the same age were successively brought to light:
- January 1995 Mamelbaye Tomalt, driver to the Department of Geological and Mining Research, a remarkably preserved mandible of Australopithecus known as Abel, leading to the definition of the species Australopithecus bahrelghazali.
- January 1996 on this same site, KT 12, Alain Beauvilain discovers an upper premolar belonging to a second individual of the same species and the site of KT 13, Mahamat Kasser, engineer geologist in the mining project, updating a fragment of maxilla a third individual.
- July 2000 Gongdibé Fanon, an engineer at the Department of Mines and Geology, NRAC posted on the site KT 40, discovered the jaw of another hominid.
- July 2001, a skull, which has a deformation is found by Ahounta Djimdoumalbaye. This skull is nicknamed Toumai.
- 2002, four partial and fragmentary mandibles both published in 2002 and both published in 2005.
- 2002 and 2005, four isolated teeth, including 3 published in 2002 and one in 2005.
Sahelanthropus tchadensis presents a series of ancestral character as a small cranial capacity, a bone basioccipital triangle truncated and the petrous part of temporal bone oriented at 60 degrees to the line parallel to the frontal plane.
This mosaic of primitive and derived features for authors indicates that Sahelanthropus tchadensis occupies a phylogenetic position of hominin strict, close to the human-chimp divergence.
The attachment of the branch Toumai hominines no doubt, for the Franco-Chadian team that discovered and for some of the scientific community.
Image: Djurab desert in Chad, 800 km north of Ndjamena.