My research is focused on understanding the role of climatic and ecological change in human evolution. I primarily use stable isotopes to study environments and dietary change in hominins, primates, and other mammals. Complementary isotope studies of modern African ecosystems play an important role in my approach to paleoecology and paleoclimate.
Current work is focused on a project entitled "A diet for all seasons: the role of intra-annual variability in the evolution of hominin diet in East Africa" (NERC). Other ongoing projects are focused on the evolution of hominin and primate diets in Africa, Plio-Pleistocene paleoenvironments in eastern Africa, and ecology of modern and historical primates and other mammals.
early Hominin environments
I am using stable isotope records in teeth and sediments to reconstruct climate and ecology over the past 6 million years in eastern Africa. These projects are done in collaboration with paleontology and archaeology projects working on Pliocene and Pleistocene sites in the Lake Victoria and Lake Turkana regions. Current work is focused on investigating the relationships between long-term climatic and ecological change across eastern Africa using carbon isotope records of herbivore diet and oxygen isotope records of aridity and seasonality.
diets of modern and fossil primates
I use stable isotopes in feces, hair, and teeth to study diet and other aspects of ecology in primates, particularly baboons and great apes. Current work is focused on (1) understanding long-term diet change in fossil primates in Africa, and (2) a systematic isotopic survey of recent and historic African primates, using teeth and hair from field and museum collections, to understand the extent of C4 feeding among extant lineages as well as understanding oxygen isotopic variation in primate tissues.
ecology of modern african herbivores
I am interested in modern herbivores as they relate to understanding ecological processes in hominin environments in Africa. Current work includes studies of herbivore diet, historical changes in herbivore ecology (particularly megaherbivores), and the taphonomy of herbivore skeletal remains. I have conducted extensive fieldwork in protected areas in Uganda, particularly Queen Elizabeth National Park.