Amino Acid Racemization Dating of the Middle Stone Age of Africa: Improvement of Precision with Ostrich Eggshell

George Washington University, Washington DC

Investigators

Abstract

This research is aimed at developing dating techniques for African archaeological sites that are too old to be dated by radiocarbon (>45,000 years before present) and which lack appropriate volcanic materials for high-precision argon-argon dating. The methods may also help to resolve problems of chronology and disturbance in archaeological sites. Such chronological resolution is essential if we are to understand such issues as the African origins of modern humans and the origins of modern behavior, both of which may relate back to the time period of the late Middle and upper Pleistocene (40,000-200,000 years before present) and the associated Middle Stone Age culture. The proposed research would improve the precision of amino acid racemization dating of ostrich eggshell (one of the more common materials in archaeological sites), through analysis of patterns of spatial and temporal variation in temperature at six African sites in Tanzania, Botswana, Namibia and South Africa. Knowledge of the Pleistocene temperature histories of these sites will also indicate how each region (tropical vs. temperate zones) reflected global cooling and warming patterns during the late Pleistocene and allow evaluation of human response to these climatic variations.