Dataset for: Paleoenvironmental models for Australia and the impact of aridification on blindsnake diversification

Aim: Shifts in diversification rates of Australian flora and fauna have
been associated with aridification, but the relationship between
diversification rates and aridity has never been quantified. We employed
multiple approaches to accurately reconstruct paleoenvironments of
Australia for the first time. We used this information, and
phylogenetic-based analyses, to explore how changes in temperature and
increasing aridity during the Neogene influenced the diversification of
the Australian blindsnakes. We tested whether diversification rates differ
between arid-adapted and mesic-adapted lineages. Taxon: Typhlopidae,
Anilios blindsnakes Location: Australia Materials and Methods: We
estimated the historical biogeography of blindsnakes using BioGeoBEARS. We
synthesised multiple approaches to reconstruct paleotemperature and
paleoaridity of Australia during the Neogene. We fit several birth-death
models and estimate diversification rates under paleoenvironmental
conditions using RPANDA. We further compare diversification rates between
arid-adapted lineages versus mesic-adapted lineages using ClaDS and
GeoHiSSE. Results: Ancestral area estimation indicated Australian
blindsnakes have tropical grassland origins. We found that
Australia-specific regional paleotemperature and paleoaridity provided a
better explanation for diversification rate variation than global
paleotemperature. Specifically, our best-fitting model indicated that
speciation rates of blindsnakes decreased with increasing aridity. We
found no difference in diversification rates between arid- and
mesic-adapted lineages. Main conclusions: Soon after dispersing to
Australia, the common ancestors of Australian blindsnakes diversified
rapidly in mesic habitats during the early Miocene. However, as the
continent became increasingly arid, diversification rates decreased. We
found that shifts in the environment led to the emergence of two major
clades: one remaining in primarily mesic habitats and the other adapting
to the expanding arid biome. Our results emphasise the importance of both
arid and tropical biomes as sources and sinks of diversification.