Selection and gene duplication associated with high-elevation diversification in Pristimantis, the largest terrestrial vertebrate genus

The genus Pristimantis is a hyper-diverse clade of frogs that develop terrestrially and can live at extreme elevations in the Andes Mountain range. Despite their dominance among Andean amphibians, the molecular evolution of Pristimantis frogs remains poorly understood and no formal comparative genomics analyses have been undertaken thus far. In this study, we compared new transcriptome sequences of seven Pristimantis species to those of other frog species and tested for positive selection and duplication in candidate genes that may underlie Pristimantis diversification, evolution of direct development, and adaptation to high-elevation environments. We find many genes uniquely under positive selection in Pristimantis that contribute to our understanding of how this clade diversified into high elevation ecosystems. We also find numerous genes and pathways selected for across high elevation species and direct developers that provide targets for functional analysis in future studies of these life history traits.