Ancient habitat shifts and organismal diversification are decoupled in the African viper genus Bitis (Serpentes: Viperidae)

摘要: Aim: The expansion of open habitats during the mid-Miocene has been hypothesized as a driver allopatric speciation for many African taxa. This habitat-dependent mode diversification implicated in shift from C3 (e.g. forest/woodland) to C4 dominated systems (i.e. savanna, grasslands) number squamates. We examined this hypothesis using genus viperid snakes (Bitis) with both habitat and forest-dwelling representatives. Location: Africa. Methods: A comprehensive multilocus dataset was used generate calibrated species tree multispecies coalescent model. Individual gene trees patterns nuclear allele sharing were assess monophyly isolation. To test evolution hypothesis, we generated an ancestral character state reconstruction closed dated phylogeny. related timing forest/woodland contraction Results: Bitis originated Oligocene, level late Miocene/Pliocene. Four well-supported clades correspond recognized subgenera Bitis, Keniabitis, Macrocerastes Calechidna. Several previously unrecognized lineages potentially represent cryptic species. Main conclusions Habitat-dependent does not appear have main generic viperine diversification: at least one clade moved into forest Miocene, long after had contracted fragmented. Forest-dependent diversified only presumably became further reduced extent, fitting model speciation. Although our results do favour general pattern cladogenesis within subgenus Calechidna “arenicolous” (Bitis caudalis complex) “rupicolous” (B. Atropos-cornuta complex), corresponds aridification southwest suggests there are subtleties captured broad category, which relevant understanding role evolution.