Vipers on the Scene: Assessing the Relationship Between Speciation and Climatic Niche Evolution in Venomous Snakes (Reptilia: Viperidae)

摘要

Abstract Evolutionary radiations have been a key paradigm in studying species richness and their temporal and geographic variation. These patterns have been associated with the interaction between the rate at which species originate and the rate at which phenotypic traits evolve. Nevertheless, despite extensive empirical testing, questions remain regarding the prevalence of the coupling between these rates within lineages. Climatic niche evolution is an important driver of speciation since niche divergence and niche conservatism may result in reproductive isolation. Here, we test whether the rate of climatic niche evolution influences the speciation rate for a globally distributed venomous snakes’ clade, the Viperidae family. Contrary to expectations, we found no general relationship between climatic niche evolution rates and vipers’ speciation rates. Our results showed that speciation during the radiation of vipers could have occurred without strong ecological niche divergence, perhaps through a non-adaptive process that could still include a complex pattern of iterated adaptive and non-adaptive radiations.