My research program centres on understanding the earliest events in the evolution of the order Primates, using the fossil record. My particular area of focus is the evolution, anatomy, and ecology of plesiadapiforms.

Plesiadapiforms are Paleocene-Eocene fossil mammals known from North America, Europe and Asia — their temporal distribution stretches from approximately 65 to 40 million years ago.  The group comprises an impressive diversity:  over 120 species, grouped into 11 distinct families, including primitive forms (e.g. Purgatorius) that are little differentiated from the earliest placental mammals known, and very derived taxa (e.g. Picrodus) that are among the most distinctive Paleocene mammals known.

The systematic position of plesiadapiforms is an area of continuing debate.  My work has suggested that they should be considered the most primitive primates, making them the taxa of greatest important for understanding the process by which primates branched off from the rest of Mammalia.

I am also involved in a large collaborative project with researchers from the United States and Europe to elucidate the Tree of Life for Mammals, and in describing material from groups whose relationships with Primates is even more in debate (e.g. apatemyid, mixodectids).

Opportunities may be available for students to do fieldwork and assist in other research activities. Recent field research has included work at Donald Quarry located in the Eastern Crazy Mountains Basin of Montana. This quarry is a rich source of Paleocene fossil mammals.