Doctoral Dissertation Research: Characterization of a modern East African ecosystem to inform reconstructions of hominin diet

Suny At Stony Brook, Stony Brook NY

Investigators

Abstract

Diet is an important factor in studies of human evolution because it is linked to behavior, morphology, and ecology. This doctoral dissertation project seeks to increase our understanding of the diets of early human ancestors through analysis of modern East African ecosystems. The student co-PI will evaluate the nutritional and mechanical properties of dominant savanna and wetland plants, in addition to commonly eaten and avoided baboon foods, across gradients of seasonal and microhabitat variability. Previous work has shed light on broad habitat and food preferences of early humans, and this project's focus on seasonality and microhabitat will provide important new data to augment past studies. This project will support student and research assistant training in ecological field methods, public science outreach activities designed to reach students from groups underrepresented in STEM fields, and conservation efforts at the research site. This project will address the lack of ecological data currently available for reconstructing diet in Plio-Pleistocene hominins by studying the mechanical properties of foods that may have been accessible to hominins. The researchers will conduct fieldwork across both the wet and dry seasons in Amboseli National Park, Kenya, a site known for its high microhabitat heterogeneity and large yellow baboon (Papio cynocephalus) populations. They will establish sampling transects in different microhabitats (grassland, wetland, scrubland, etc.) and collect dominant tree, forb, herb, grass, and sedge species in each transect (where applicable). Commonly eaten and avoided baboon foods will also be collected within each transect; baboons are a suitable ecological analogue for early humans because of their wide dietary niche and preference for savanna habitats. A portable mechanical tester will be used on fresh plant material to measure the hardness and toughness of the component parts (root, stem, leaf, etc.) of each sampled species. Once mechanical testing is complete, remaining plant samples will be dried and analyzed for fiber, lignin, fat and oil, protein, and trace metal content. The resulting nutritional and mechanical properties data incorporating both seasonal and microhabitat variability can be used to build predictive models of early human foraging behavior.