Format: ORAL

Anglica Gallego-Narbn1, Jun Wen2, Luis Valente3,4, Gabriel Johnson2, Marina Coca-de-la-Iglesia1, Nagore G. Medina1,5, Mario Fernndez-Mazuecos1,5, Virginia Valcrcel1

1 Universidad Autónoma de Madrid, Madrid, Spain 2 Smithsonian National Museum of Natural History, Washington DC, USA 3 Naturalis Biodiversity Center, Leiden, The Netherlands 4 University of Groningen, Groningen, The Netherlands 5 Centro de Investigación en Biodiversidad y Cambio Global (CIBC-UAM), Madrid, Spain

Dendropanax is a species-rich genera of Araliaceae and a classic example of the Asian-Neotropical disjunction or amphi-pacific tropical disjunction. Previous biogeographic reconstructions of the genus point to an East Asian origin and posterior colonization of the Neotropics, with higher diversity in the Neotropical clade. Here we investigated the role of climatic niche evolution and colonization events in the diversification of the functionally and climatically heterogeneous genus Dendropanax. We used Hyb-Seq phylogenomics on 237 Araliaceae species to obtain time-calibrated nuclear and plastid phylogenies used to perform biogeographic analyses, diversification models, and climatic niche and functional trait reconstructions (habit, leaf type, dimorphism, and area, stipule and trichome presence) for Dendropanax and phylogenetically close genera. Curated databases were used to estimate current and ancestral climatic niches (6,496 occurrences) and leaf areas (910 measurements) using a novel probabilistic approach that considers niche heterogeneity. Diversification in Dendropanax followed a temperature-based model with a decrease of diversification towards the present. After an Asian origin, successive colonizations of Central and South America preceded climatic niche expansions and shifts towards warmer and drier climates coupled with an increase in leaf area and variability and associated with the persistence of high diversification rates in the Neotropical Dendropanax clade in comparison with the Asian Dendropanax clade. Given that the evolution of leaf area followed the colonization of the Neotropics, we believe that this trait could be associated with the adaptation to the climatic conditions in the colonized area. Our results support the relevance of colonization events, climatic niche evolution and functional trait shifts to explain phylogenetic diversification in the intercontinental tropical Dendropanax.