A complete mandible of Homo erectus was discovered at the Thomas I quarry in Casablanca by a French-Moroccan team co-led by Jean-Paul Raynal, CNRS senior researcher at the PACEA[1] laboratory (CNRS/Université Bordeaux 1/ Ministry of Culture and Communication). This mandible is the oldest human fossil uncovered from scientific excavations in Morocco. The discovery will help better define northern Africa's possible role in first populating southern Europe.

A Homo erectus half-jaw had already been found at the Thomas I quarry in 1969, but it was a chance discovery and therefore with no archeological context. This is not the case for the fossil discovered May 15, 2008, whose characteristics are very similar to those of the half-jaw found in 1969. The morphology of these remains is different from the three mandibles found at the Tighenif site in Algeria that were used, in 1963, to define the North African variety of Homo erectus, known as Homo mauritanicus, dated to 700,000 B.C.

The mandible from the Thomas I quarry was found in a layer below one where the team has previously found four human teeth (three premolars and one incisor) from Homo erectus, one of which was dated to 500,000 B.C. The human remains were grouped with carved stone tools characteristic of the Acheulian[2] civilization and numerous animal remains (baboons, gazelles, equines, bears, rhinoceroses, and elephants), as well as large numbers of small mammals, which point to a slightly older time frame. Several dating methods are being used to refine the chronology.

The Thomas I quarry in Casablanca confirms its role as one of the most important prehistoric sites for understanding the early population of northwest Africa. The excavations that CNRS and the Institut National des Sciences de l'Archéologie et du Patrimoine du Maroc have led there since 1988 are part of a French-Moroccan collaboration. They have been jointly financed by the French Ministry of Foreign Affairs[3], the Department of Human Evolution at the Max Plank Institute in Leipzig (Germany), INSAP[4] (Morocco) and the Aquitaine region.

[1] De la Préhistoire à l'Actuel : Culture, Environnement et Anthropologie (From Prehistory to Present day: Culture, Environment, and Anthropology)
[2] Acheulians appeared in Africa around 1.5 million years ago and disappeared about 300,000 years ago, giving way to Middle Stone Age civilizations. Their material culture is characterized by the production of large stone fragments shaped into bifacial pieces and hatchets, and of large sharp-edged objects.
[3] (Mission archéologique « littoral » Maroc, led by J.P. Raynal).[4] (INSAP-Rabat) which falls under the authority of the Moroccan Ministry of Cultural Affairs.