One of the most important evolutionary transitions in human prehistory was the rise of modern humans (Homo sapiens) from earlier hominids. A newly reported fossil from Tanzania provides an important new data point necessary to understand this transition.
Homo erectus/ergaster probably gave rise to Homo sapiens (modern humans) somewhere in Africa. It is very likely that earlier hominids (H. erectus/ergaster) and later hominids (some sort of archaic H. sapiens) co-existed, and it is also the case that during this transitional period there would be individuals with either a mixture of traits that define classic H. erectus/ergaster or that have traits that are somewhere in between the two. Throughout much of the 20th century, and into the present century, there have been many finds of such individuals, and this new fossil frontal bone (from the front of the skull) (EH06) is probably one of them. The scientists reporting this find suggest that this frontal bone falls outside the range of H. erectus/ergaster, yet it is clearly distinguishable form modern humans.
One of the most important aspects of this find is that it comes along with a collection of other fossils, of various mammals, and stone tools, and is in a dated context. The context is stated with the aid of stratigraphy from the area and by using Electron Spin Resonance of an animal tooth found in the collection. The dating is pretty solid, and places this frontal bone at between 88 and 132 thousand years ago. Elsewhere in Africa, at about this time, there are human remains that are probably more like modern H. sapiens than this frontal bone appears to be, conforming with the idea of co-existence of different hominids, or a great deal of variation in the extant population, at that time.
DOMINGUEZRODRIGO, M., MABULLA, A., LUQUE, L., THOMPSON, J., RINK, J., BUSHOZI, P., DIEZMARTIN, F., ALCALA, L. (2008). A new archaic Homo sapiens fossil from Lake Eyasi, Tanzania. Journal of Human Evolution DOI: 10.1016/j.jhevol.2008.02.002