Early Man Thrived Where the Sahara Desert is Today
Jennifer R. Smith, Ph.D., Washington University assistant professor of earth and planetary sciences in Arts & Sciences, and her doctoral student Johanna M. Kieniewicz, are conducting analyses of ancient freshwater snail deposits and carbonate silts from a small lake (now dry) in the Kharga Oasis of western Egypt to reconstruct climatic conditions during the lifetime of the lake. Their analyses support a surprising picture of arid Egypt: 130,000 years ago, what everyone considers an eternal desert was actually a thriving savannah, complete with humans, rhinos, giraffes and other wild life.
Evidence for hominin (prehistoric human) presence abounds near the lake in the form of Middle Stone Age artifacts such as stone scrapers and blades.
"The artifacts provide a record that people were coming to the lake," said Smith. "Genetic evidence suggests that 100,000 to 400,000 years ago was a critical time in the evolution and dispersal of African hominins. Our climate data from this 130,000-year-old humid event suggest that this would have been a particularly good time for a northward migration through Africa following reliable water resources, since it seems to be the strongest humid phase in this region over the past 400,000 years. We're also testing the hypothesis that humid events were more frequent than previously thought, which would have allowed for greater mobility throughout the region."