Data from: Tracing the diversification history of a Neogene rodent invasion into South America

We investigated spatial patterns of evolutionary relatedness and
diversification rates to test hypotheses about the historical
biogeographic processes underlying the radiation of Neotropical rats and
mice (Sigmodontinae, ~400 species). A negative correlation between mean
phylogenetic distance and diversification rates of rodent assemblages
reveals a pattern of species co-occurrence in which assemblages of closely
related species are also the fastest diversifying ones. Subregions of the
Neotropics occupied by distantly related species that are on average more
slowly diversifying include Central America, northern South America, and
the Atlantic forest. In southern South America, recent species turnover
appears to have been higher. Ancestral locations for the main tribes of
sigmodontines were also estimated, suggesting eastern South America and
the Amazonian lowlands were colonized before some central Andean regions,
even though the latter are now centers of species richness for these
rodents. Moreover, a past connection between the tropical Andes and the
Atlantic Forest is suggested by our results, highlighting a role for a
hypothetical arc connecting the two biomes, which would have impacted many
other groups of organisms. Whether rapid, recent speciation in some
regions is related to Quaternary climatic fluctuations and the young age
of sigmodontines (~12.7 Ma crown age) or instead to intrinsic traits of
these rodents remains an open question. If the former is true, we
hypothesize that contrasting trends will characterize older Neotropical
clades.