Paper No. 13
Presentation Time: 11:45 AM


MICHEL, Lauren A.1, PEPPE, Daniel J.1, MCNULTY, Kieran P.2, DRIESE, Steven G.3, LEHMANN, Thomas4, NIGHTINGALE, Sheila5, HORNER, William H.1, DUNSWORTH, Holly M.6, HARCOURT-SMITH, William E.H.7 and LUTZ, James A.8, (1)Department of Geology, Baylor University, One Bear Place #97354, Waco, TX 76798-7354, (2)Department of Anthropology, University of Minnesota, 395 Hubert H. Humphrey Center, 301 19th Avenue South, Minneapolis, MN 55455, (3)Terrestrial Paleoclimatology Research Group, Dept. of Geosciences, Baylor University, One Bear Place #97354, Waco, TX 76798-7354, (4)Abteilung Paläoanthropologie und Messelforschung, Forschungsinstitut und Naturmuseum Senckenberg, Senckenberganlage 25, Frankfurt, D-60325, Germany, (5)Archaeology, CUNY Graduate Center, 365 Fifth Avenue, New York, 10016, (6)Department of Sociology and Anthropology, University of Rhode Island, 507 Chafee Building, 10 Chafee Road, Kingston, RI 02881, (7)Department of Vertebrate Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, (8)College of the Environment, University of Washington, Box 352100, Seattle, WA 98195-2100,

While it is accepted that environment plays a key role in evolution and adaptation of early hominoids, pinpointing the specific environments in which they lived is often difficult. Here we present results from a multi-proxy study of Early Miocene deposits from Rusinga Island, Lake Victoria, Kenya which specifically place Proconsul and Dendropithecus within a closed-canopy forest. Macroscopic features observed at the R3 locality include a red-brown paleosol containing in situ tree stump casts and permineralized root systems, and an overlying sandstone with fossil leaves. Additionally, specimens of Proconsul and Dendropithecus have been found weathering from the same paleosol horizon. GIS work was used to placed the tree stumps and some of the roots into a spatial framework. Micromorphology, clay mineralogy, bulk soil geochemistry, and paleobotanical proxies were assessed, and paleotemperature, paleoprecipiation, and landscape hydrology were reconstructed. This project offered the opportunity for multiple proxies, including linear regression models from leaves and CIA-K and CALMAG from the paleosols, to be compared. Based on this work, we can now definitely place the basal catarrhine Dendropithecus and the early ape Proconsul within a closed-canopy forest environment. Prior associations of these taxa with mixed or even open habitats may represent lateral or temporal variation on Rusinga, but are based on time-averaged fossil assemblages.