Archaic African forms

Homo sapiens is rooted in the various forms of large-brained hominins that appeared during the Middle Pleistocene (780,000 to 128,000 BC). The definition of the species morphotype has given rise to much debate, not least because of the great variability of current populations. The inclusion of ancient forms has further complicated the task of paleoanthropologists, who have often equated the concepts of "anatomically modern man" with that ofHomo sapiens. In particular, it is the retraction of the face beneath an increasingly globular brain cavity that characterizes our species. However, the face of today's humans has also retained many primitive features already present in Homo erectus. It is not, however, the product of a simple allometric reduction of the prognathic faces of African forms associated with Homo rhodesiensis or Homo heidelbergensis. In fact, these taxa should probably be excluded from our direct ancestry because of the derived characters they display. As early as 300,000 years BC, human fossils discovered at Jebel Irhoud in Morocco represent the earliest forms ofHomo sapiens known to date. These individuals combine a facial morphology close to that of present-day humans with a large, but still not very globular, brain. The appearance of our species appears to be the product of evolution on a pan-African scale and, in behavioral terms, is associated with the transition from Early Stone Age to Middle Stone Age lithic industries.