GIS INTERPRETATION OF FOSSIL DISTRIBUTION OF AN EKEMBO BEARING SITE FROM THE EARLY MIOCENE, RUSINGA ISLAND, LAKE VICTORIA, KENYA

Rusinga Island, Lake Victoria, Kenya, has been one of the most intensely worked paleoanthropological sites, with extensive paleontological research conducted there for the last 80 years. Much of the research has focused on the important catarrhine fossils remains, including those of the early ape Ekembo, but the extensive vertebrate, invertebrate, and botanical fossils from Rusinga make it a touchstone for studies of Old World Neogene paleobiology. One site in particular, R3, has made important contributions to our knowledge of catarrhine paleoecology based on the discovery of four Dendropithecus macinnesi partial skeletons and later the discovery and reconstruction of a closed-canopy forest. Such a wealth of fossils argues for conducting extensive fine-scaled excavations, but targeted excavations have previously met with mixed results. In 2011, our team used a total station to document 3D provenience data for all fossil surface finds 2cm and over – collecting 972 points. Here, we report the results of a preliminary study of the R3 fossil distribution using GIS. Results from a hotspot analysis show a clustering of data points (fossil discoveries) with a z-score of 108 that is higher than expected from a random distribution which would have a z-score of 0.4. This strong clustering coupled with a geological survey suggests that all of the fossils found at R3 are produced from a single layer and identifies potentially promising areas for future excavations. Better digital elevation models (DEMs) and liDAR data, which is currently absent from Rusinga Island, will allow for interpolation of existing data and better predication of excavation sites in the future. This project underscores the value of documenting surface scatters and GIS-based approaches to paleontological exploration elsewhere on Rusinga Island and at other fossil localities.