Researchers from the United States, their graduate students, and colleagues from the National Museums of Kenya are conducting archaeological and geological research on the islands of Rusinga and Mfangano, near the Kenyan shores of Lake Victoria. Genetic, fossil, and archaeological evidence suggest that the origins of living humans can be traced to early populations of Homo sapiens from the Late Pleistocene of eastern Africa, roughly 130,000-40,000 years ago. Research on the sites of Rusinga and Mfangano provides an important opportunity to examine the biological and behavioral diversity among these eastern Africa source populations, and the social and environmental contexts that may have contributed to this diversity and ultimately, the evolutionary success of our species. Located in equatorial eastern Africa, Lake Victoria is the largest lake on the continent and today supports diverse ecosystems and dense human populations. Past lake size has periodically dramatically fluctuated between completely drying up and nearly doubling in size, and these events have likely had major impacts on the composition, size, and distribution of surrounding environments and human populations. Using archaeological survey and excavation and a variety of field geological and laboratory-based geochemical and geophysical methods, past human diversity is investigated through the study of Middle Stone Age artifacts, site age is determined by correlating and dating associated volcanic ash deposits, and ancient environments are reconstructed through the analysis of sediments and fossils. Some of these fossils include extinct species, as well as extant taxa, that are indicative of arid grassland settings, substantially differing from today's regional environment. Integration of these data with detailed studies of neighboring lake basins contributes to our understanding of past and present patterns of climate change, particularly the timing and periodicity of pan-African intervals of increased aridity.
This study provides an improved understanding of Late Pleistocene paleoenvironments of eastern Africa, which has clear implications for attempts to understand and moderate the effects of global climate change today. This two-year project is providing field and laboratory training, thesis research opportunities, and professional experience for US undergraduate and graduate students. Additionally, the project is fostering collaborations between US universities and contributes to the National Museums of Kenya and other local cultural heritage museums on Rusinga and Mfangano.
