Evolutionary dynamics of climatic niche influenced the current geographical distribution of Viperidae (Reptilia: Squamata) worldwide

An understanding of patterns of climatic niche evolution has important implications for ecological and evolutionary theory and conservation planning. However, despite considerable testing, niche evolution studies continue to focus on clade-wide, homogeneous patterns, without considering the potentially complex dynamics (i.e. phylogenetic non-stationarity) along the evolutionary history of a clade. Here, we examine the dynamics of climatic niche evolution in vipers and discuss its implication for their current patterns of diversity and distribution. We use comparative phylogenetic methods and global-scale datasets, including 210 viper species with phylogenetic and climatic data. We find that climatic niche evolution in Viperidae shows an overall pattern of phylogenetic conservatism, but with different dynamics depending on the niche feature (niche breadth or niche position) and the evolutionary history of particular lineages within the family, thus resulting in phylogenetic non-stationarity. Indeed, we find several shifts in niche breadth evolution that were probably influenced by the main geological and environmental changes experienced during the evolutionary history of the family. These results highlight the importance of considering complex patterns of climatic niche evolution and their role in shaping patterns of diversity and distribution.