Evolutionary Processes of Diversification in a Model Island Archipelago

Abstract

Long celebrated for its spectacular landscapes and strikingly high levels of endemic biodiversity, the Philippines has been studied intensively by biogeographers for two centuries. Concentration of so many endemic land vertebrates into a small area and shared patterns of distribution in many unrelated forms has inspired a search for common mechanisms of production, partitioning, and maintenance of life in the archipelago. In this review, we (a) characterize an ongoing renaissance of species discovery, (b) discuss the changing way biogeographers conceive of the archipelago, (c) review the role molecular phylogenetic studies play in understanding the evolutionary history of Philippine vertebrates, and (d) describe how a 25-year Pleistocene island connectivity paradigm continues to provide some explanatory power, but has been augmented by increased understanding of the archipelago's geological history and ecological gradients. Finally, we (e) review new insights provided by studies of adaptive versus nonadaptive radiation and phylogenetic perspectives on community ecology.