In spring of 2013 Philip A. Slater, PhD candidate at the University of Illinois, was awarded a Leakey Foundation research grant for his project entitled “Planning and technological organization in the Kenyan MSA and LSA.” The following is a short update on his progress.
Small and intentionally dug hole that contained about 550 artifacts. The people at the site (~94,000 years ago) appeared to have dug a hole and swept up their mess – small sharp shards of glass from resharpening and shaping various types of tools.
My dissertation research, supported in part by The Leakey Foundation, focused on the long-term changes in stone tool technology that accompanied the evolution of modern humans in East Africa over the past 200,000 years. More specifically, I investigated the Middle (MSA) to Late Stone Age (LSA) technological transition and the adoption of standardized ‘blade’ technology during the LSA (≤50,000 BP). In order to assess levels of standardization I used a combination of typological classification and quantitative morphometrics to analyze obsidian artifact assemblages from three archaeological sites in Kenya’s central Rift Valley.
I found evidence for the systematic curation of late MSA artifacts, which contrasts with the systematic production of standardized LSA artifacts. Tools from MSA assemblages typically have long and complex use-lives, with repeated sessions of resharpening or reshaping maintenance. In contrast, tools from LSA blade assemblages tend to have short use-lives with very few bouts of resharpening. This tradeoff in longevity was counteracted by higher rates of production with standardized components that replaced used tools, rather than resharpening them. I also used scanning electron microscopy of use-wear patterns on individual artifacts to analyze their functions. This analysis provided independent evidence for the long use-lives of some classes of late MSA artifacts, such as points and scrapers, and shorter use-lives for LSA blade tools, most specifically microliths.
Some points (most likely for hunting spears) we found during the excavation
Together, these data provide robust evidence for evaluating the role of technological planning in the evolution of modern human adaptations. By standardizing and compartmentalizing the different production stages of blade tools, LSA knappers were able to more efficiently use their raw materials, time and energy. This technological efficiency is a clear expression of enhanced planning capacities in LSA humans, and provides support for subtle, but significant, advances in cognition during the late MSA. I plan to complete the writing of my dissertation by May 2015 and to publish multiple articles on different facets of MSA and LSA technological organization soon after.