Dispersal to or from an African biodiversity hotspot?

Biodiversity hotspots are centers of endemism and thus contain many range-restricted species. In addition, within these hotspots are often widespread species that might have originated within a hotspot before dispersing to neighboring or distant regions. We test this hypothesis through a phylogeographic analysis of a miniature leaf litter frog, Arthroleptis xenodactyloides, that has a large distribution throughout the Eastern Arc, a biodiversity hotspot, and other regions in East Africa. Maximum likelihood and Bayesian estimates of the mitochondrial gene phylogeny are used as a proxy for understanding the evolutionary history of diversification and the historical relationships between populations. The north-south range of this species extends for approximately 1900 km; our sampling covers approximately 85% of this range. Using phylogenetic comparative methods, we estimate the region of origin and direction of dispersal within A. xenodactyloides. We compare contrasting hypotheses of lati...