Phylogenomic insights into the biogeography and evolution of Weinmannia (Cunoniaceae)

The objective of the study was to test the hypothesis that Weinmannia is a lineage of extratropical origin that recently reached and then diversified extensively in tropical Andes. Using a 2bRAD seq approach to generate a time-calibrated phylogeny for the genus, we found that extratropical species were placed as sister to the rest of Weinmannia and that younger clades were distributed towards northern latitudes. Although Weinmannia exhibited low niche conservatism in elevation and latitude, trait reconstructions of climatic variables showed that the common ancestor of Weinmannia occupied relative cool and rainy climates, depicting high conservatism of climatic niche and precipitation across the phylogeny. Results suggest that the Andes uplift created habitats with suitable environmental conditions, providing a dispersal route for extant Weinmannia to colonize the tropical. This study provides further insight into biogeographic processes underlying the intriguing origins of Andean hyper-diversity of plant lineages.