“Robust” Hominids and Plio–Pleistocene Paleogeography of the Turkana Basin, Kenya and Ethiopia

The purpose of this paper is twofold: (1) to provide an up-to-date chronology of Pliocene and Pleistocene sediments in the Turkana Basin from which early hominids have been collected, and (2) to document serious difficulties with some published paleogeographic models of the region (Findlater, 1976; Vondra and Bowen, 1978; de Heinzelin, 1983) and to replace those models with a new model that accords better with stratigraphic observations made over the past six years. The chronology will be treated summarily here, without providing primary data on new age determinations, because revisions that have been made since the last review (Brown et al., 1985) do not seriously affect the age estimates of “robust�? hominid specimens. A full review of the chronologic placement of all hominid specimens from the region has been prepared for publication elsewhere (Feibel, et al., 1988). Most of the localities mentioned in the text are shown in Fig. 22.1.