Dr. Voss’s primary research interests are the evolution of marsupials and the systematics and biogeography of other Neotropical mammals that inhabit moist-forest habitats in Amazonia and the Andes. He is actively involved in long-term revisionary studies on several groups that have radiated extensively in lowland and montane rainforests, including didelphid marsupials, caviomorph rodents (erethizontids and dasyproctids), and murid rodents. For several of these groups, he is also collaborating with molecular researchers on phylogenetic studies designed to provide a stable basis for higher-level classifications, historical biogeography, and comparative analyses of ecobehavioral adaptations. The collection and analysis of faunal inventory data, especially from long-term projects in tropical rainforest habitats, is another research focus.