Arid ecosystems cover one third of Earth's land surface, and many have levels of endemism as high as tropical biomes. Despite supporting a rich biodiversity, arid ecosystems are generally overlooked as models for investigating evolutionary processes. The southern Africa region is characterized by a high interior plateau bounded on three sides by a steep escarpment, the presence of a west-to-east gradient of increasing moisture, and hyper-arid to humid habitats. This complex topography and climatic variation is reflected at the landscape level with seven distinct vegetation types or biomes. Despite a large number of endemic species (the greatest regional concentration in Africa), the role of evolutionary, ecological and climatic processes in shaping bird population histories has been sorely neglected in southern African arid ecosystems. This proposal aims to understand the processes that have driven the diversification of 12 bird taxa in the southern African arid zone by fully utilizing the tools provided by molecular ecology and species-distribution modelling.
A collaboration between the University of California-Berkeley, Texas A&M University, and several southern African institutions -- including universities, museums and conservation agencies -- this proposal will include the training and exchange of graduate and postdoctoral scholars, and involve undergraduate students in research.