Speaker: Dr. Enquye Negash, Postdoctoral Scientist at the Center for the Advanced Study of Human Paleobiology, George Washington University
Title: "Modern African ecosystems as analogues: Implications for hominin environments"
Environmental change is considered a key driver of human evolution and several hypotheses have been proposed to explain the outcomes of proposed environmental changes. One approach to testing these hypotheses is reconstructing the paleoenvironment of hominin bearing sites and looking for evidence of temporal change across sites. However, most paleoenvironmental reconstructions from hominin fossil bearing sites indicate a “mosaic habitat” which simply means a mix of habitat types. Thus, to better under the paleoenvironmental context of hominin evolution and make more refined habitat reconstructions, my research is focused on studying modern African ecosystems and applying the knowledge garnered to the fossil record. In this talk, I begin by introducing my work on woody cover in modern African ecosystems. Using stable carbon isotope data from surface soils, I will present a model for reconstructing woody cover and show woody cover reconstructions for hominin fossil bearing sites in the Shungura Formation in eastern Africa. Then, I will discuss my research on the diet of fossil herbivores from the same site and compare how paleoenvironmental information we get from herbivore diet correlates to woody cover reconstructions from fossil soils. Finally, I will present my ongoing research on quantitatively characterizing modern vegetation mosaics in African ecosystems using concepts and metrics used in landscape ecology and show how information about the vegetation on the landscape relates to herbivore diet and abundance. I will conclude with a discussion on the implications of this research for reconstructing hominin environments and the need for modern calibration dataset to ground truth commonly used proxies in paleoenvironmental studies.