Change in lithic technological organization strategies during the Middle and Later Stone Ages in east Africa
This dissertation reports on archaeological research carried out in Kenya’s central Rift Valley. The primary research objective was to investigate differences in lithic technological organization strategies among archaeological sites dating to the Middle (MSA) and Later (LSA) Stone Ages. The motivation for the project was to better understand how the development of cooperative social networks by modern humans during the late MSA enabled more effective planning of tool use during the LSA. To accomplish the research objective I analyzed six flaked stone artifact assemblages from three different archaeological sites located in the Lake Naivasha basin. Three MSA assemblages from Marmonet Drift are dated >110 ka, 110-94 ka, and <94 ka; two early LSA assemblages from Enkapune Ya Muto date from >40 to 36 ka; and one LSA assemblage from Ol Tepesi dates to 19 ka. Assemblages were analyzed in four ways: 1) typological composition; 2) artifact morphometrics; 3) tool production techniques; and 4) artifact curation strategies, including use-wear analysis and retouch patterns. These assemblages provided an exceptional opportunity to examine long-term changes in human technological organization with great control over raw material quality and availability. Results of my analysis show dramatic change in lithic technological organization strategies between the MSA and LSA in terms of artifact size, shape, morphological standardization, production techniques, use, and curation. Large and heavily retouched stone artifacts, including unifacial points, scrapers, and knives, dominate MSA assemblages. Most of these tools accumulated high frequencies of use-wear traces and, along with large numbers of soft hammer retouch flakes in assemblages, indicate long artifact use-lives. These data suggest a technological organization strategy of curating large, transformable, morphologically flexible, and functionally versatile tools that had the potential to perform a wide range of unplanned tool-using activities. Conversely, smaller, thinner backed microliths with low frequencies of use-wear traces dominate LSA assemblages. End scrapers made on blades and their associated steep-edged retouch flakes represent the only major curated tool class. These data suggest that LSA technological organization strategies were geared toward the production of disposable, replaceable, and morphologically standardized tools organized in anticipation of more planned tool-using activities. The results of this research project are significant for our understanding of the evolution of human technological planning. It appears that MSA humans reacted to foraging opportunities they encountered in their environments by relying on flexible and transformable toolkits while LSA humans appear to have anticipated and strategically planned for tool-using activities with specialized toolkits. The development of cooperative social networks during the late MSA likely enhanced the ability of modern humans to plan resource acquisition strategies using mechanically efficient and standardized tool designs.
Lithic technology, Technological organization, Curation, Use-wear, Middle stone age (MSA), Late stone age (LSA), East Africa
University of Illinois - Urbana-Champaign
Networked Digital Library of Theses and Dissertations
University of Illinois at Urbana-Champaign