Professor, Keck School of Medicine, University of Southern California
He is interested in the phylogenetic relationships, adaptations, and historical biogeography of mammals. His research is now focused largely on fossil mammals from the Eocene and Oligocene of Africa. In particular, late Eocene faunas from Egypt have provided important insights into the early evolution of anthropoid and strepsirrhine primates, and also document primitive relatives of living hyraxes, elephants, sengis, tenrecs, various bat and rodent clades, and entirely extinct clades such as Hyaenodonta and Ptolemaiida. Much of this work has been undertaken in collaboration with his current and former doctoral students and has been funded by the U.S. National Science Foundation and The Leakey Foundation.