My work focuses on aspects of the geography of biodiversity, with a focus on tropical ornithology and systematics, distributional ecology, and disease transmission risk mapping. My group of students and colleagues is diverse and global, including people interested in the three themes of my interests, from many countries and backgrounds. One component of my research focuses on the alpha taxonomy of birds, as well as on the phylogeny of recently radiated clades of birds. Tied to this focus is work with the basic geography of bird distributions, and with the composition of local avifaunas, based on detailed site inventories and scientific collections around the world. My work with the geographic and ecology of species' distributions, however, has taken me into other fields, including conservation biology and planning, invasive species biology, and disease transmission systems. In the latter field, my work has focused on numerous disease systems, including Chagas Disease, malaria, dengue, leischmaniasis, and ebola/Marburg. In general, my work is collaborative in nature, and usually involves geographers, computer scientists, and biologists.