Alison Brooks (George Washington University), Richard Potts (Human Origins Program, Smithsonian Institution) and John Yellen (National Science Foundation)
Abstracts of the SAA 79th Annual Meeting
Abstract: The Olorgesailie basin, in the Rift Valley of southern Kenya, is well-known for its spectacular concentrations of Acheulean handaxes and large game butchery sites, dating from over 1 Ma to 493 ka, as well as for pioneering studies in landscape archaeology. New excavations since 2001 have revealed that these early occupations were followed by a long sequence of Middle Stone Age occupations without handaxes, beginning well before 315 ka and ending before 64ka. In this presentation, we compare cores from the later Acheulean horizons of Members 11 and 13 of the Olorgesailie formation (between 625 and 550 ka), to those of MSA sites dating from over 315 ka to after 220 ka. We demonstrate that Levallois technology begins to emerge early on in this sequence during the Acheulean, well before its appearance in dated Middle Eastern or European contexts, and we consider the implications of this for human evolution. We also show that Levallois cores are made in many different raw materials, both local and transported, and that their frequency is episodic and non-linear through time. From 220 ka on, however, most sites are characterized by industries with small standardized Levallois cores.