Paleoanthropologists and other field scientists at Gawis (pronounced "gow-wees"), in the Gona Paleoanthropological Research Project study area of Ethiopia, have discovered a "significantly complete cranium" of a human ancestor estimated to be Middle Pleistocene (~780 to 126 thousand years ago, or kya) in age.
The discovery was reported by Sileshi Semaw, Director of the Gona Project, who is based at the Stone Age Institute and Indiana University's CRAFT Research Center, USA.
The new cranium from Gawis appears to be intermediate between the earlier Homo erectus and later Homo sapiens and may be sampling a single lineage. At the discovery site and nearby areas, significant archaeological collections of Late Acheulian (ed.: up to 100 kya) stone tool-making tradition and numerous fossil animals were found, opening a window into an intriguing and important period in the development of modern humans.Link (via Panda's Thumb). The southwest portion of the project area near the Gawis River contains many active and recently active volcanoes that erupted periodically. Volcanic ash layers will hold the key to dating the Gawis cranium and associated stone tools, using the 40Ar/39Ar method among others, providing the opportunity to make this "one of the best-dated human ancestors," according to project geologist Jay Quade.
The Gawis cranium comes from a time of transition to modern humans from African Homo erectus that is poorly known. The fossil record from Africa for this period is sparse and most of the specimens are poorly dated. The few fossil crania that are known from the Middle Pleistocene of Africa present a narrow view of the range of potential anatomical variation during this period. The Gawis cranium provides us with the opportunity to look at the face of one of our ancestors.According to the press release, the face and cranium of this fossil are recognizably different from that of modern humans, but the anatomical evidence clearly indicates that it belongs to our ancestry. The form of the face and the brain are among the best means for exploring the evolutionary path of humans and the Gawis cranium preserves both areas. The Gona team is currently working to determine the age of the cranium and associated archaeology (Acheulian handaxes as well as various other animal bone), and to understand its evolutionary relationships with others known during the Pleistocene.
Image credits: Sileshi Semaw, HO, courtesyAP/Stone Age Institute/Panda's Thumb, borrowed for news-reporting and comment purposes.