Among his field experiences are expeditions to jungles in Venezuela, Guyana, Suriname, and Madagascar. He earned his Ph.D. in anthropology at Washington University in St. Louis. His doctoral research focused on the biogeography of nine primate species in Guyana, South America. Following his doctoral work he undertook research on the conservation biogeography of lemurs in Madagascar. Dr. Lehman and his students are currently exploring innovative approaches to determine how landscape changes in forest composition influence lemur ecology in Madagascar. He is also a dedicated and enthusiastic lecturer, having been nominated three times for TVOs Best Lecturer Competition.