Sourcing Oldowan and Acheulean Stone Tools at Oldupai Gorge (Tanzania)

Abstract

Hominins habitually moved across landscapes to forage for resources, which can be investigated by the probabilistic attribution of stone tools to raw material sources. The sources that were available to Pleistocene hominins at the UNESCO World Heritage Site of Oldupai Gorge (Tanzania) have been studied for over a half-century. However, limited reference collections have prevented detailed investigations on the degree to which hominins transported stone tools. The primary goal of this dissertation was to identify the locations and distances over which Oldowan and Acheulean hominins transported raw materials at Oldupai Gorge and interpret the results in the context of the human evolutionary record. Fieldwork consisted of sampling metamorphic and volcanic outcrops to supplement an existing reference collection. An equally important fieldwork component consisted of conducting excavations at four occupation sites, including, from oldest to youngest, Ewass Oldupa (Oldowan), Elang’ata Oljurusi (Acheulean), Engaji Nanyori (Acheulean), and Emurutoto (Acheulean). Laboratory work consisted of studying artefact collections to obtain general information about toolmaking practices, and characterising geological samples and stone tools at the macroscopic and geochemical levels for comparative analyses using computational statistics. The overarching aim of this dissertation was to investigate whether the shift from Oldowan to Acheulean toolmaking was accompanied by equally more complex landuse strategies amidst progressive aridification. Informed by probabilistic sourcing results, the evidence presented herein indicates that the Oldowan to Acheulean transition in the Oldupai basin was accompanied by more focalised landuse. Yet, both Oldowan and Acheulean hominins altered their mobility to variable environments ranging from woodlands to steppe deserts. These behavioural responses represent possible explanations for the adaptive radiation of hominin populations across, and out of, Eastern Africa during the Early and Middle Pleistocene.