The Australian birds of paradise represent a dramatic proliferation of species characterized by the evolution of spectacular plumages, differences in behavior, particularly breeding systems, and ecological specializations. This research project will use modern numerical and computer methods to reconstruct the evolutionary history of the group and then study the evolution of morphology, behavior and ecology against this historical backdrop. The birds of paradise will serve as a paradigm for understanding the evolutionary processes that result in the proliferation of species. This study will contribute to our basic understanding of the natural processes that result in the evolution of biological diversity--particularly the evolution of avian species. Only by understanding the origin of this diversity can we assess its importance to our global ecosystem and take the action necessary for its preservation.