Format: ORAL

Dario I. Ojeda1, Anas-Pasiphae Gorel2, Gilles Dauby3, Aaron D. Pan4, Thomas Marcussen5, Samuel Vanden Abeele6, Arthur Boom7, Sandra Cervantes8, Flix Forest9, Olivier J. Hardy7, Manuel de la Estrella10

1 Department of Forest Biodiversity, Norwegian Institute of Bioeconomy Research, Norway 2 Laboratory of Plant Ecology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium 2 Forest is Life,Gembloux Agro-Bio Tech, Université de Liège, Gembloux, Belgium 3 MAP, Univ. Montpellier, IRD, CNRS, CIRAD, INRAE, Montpellier University, France 4 Museum of Texas Tech University, Texas Tech University, USA 5 Department of Biosciences, University of Oslo, Norway 6 Department of Plant Sciences, University of Cambridge, UK 7 Evolutionary Biology and Ecology, Faculté des Sciences, Université Libre de Bruxelles, Belgium 8 Department of Ecology and Genetics, University of Oulu, Finland 9 Royal Botanic Gardens, Kew, Richmond, UK 10 Departamento de Botánica, Ecología y Fisiología Vegetal, Facultad de Ciencias, Universidad de Córdoba, Spain

Previous research has highlighted the frequency of niche conservatism during the radiation of plant lineages at regional and global scales. These studies indicate that niche conservatism played a major role in the current distribution of biodiversity. A recent analysis in tropical Africa also found high prevalence of niche conservatism at the genus level in biomes (forest and savanna), indicating that niche lability (as evidenced by the presence of a genus in two biomes) is uncommon and unevenly distributed among forest tree species in Africa. Current limitations to infer the fine-scale distribution of this trait among lineages of tropical trees is the low resolution of current phylogenetic trees and a limited sampling at the species level of the analyzed taxa. Here we explored the distribution of niche lability within an endemic African lineage of tropical trees that contains 16 genera (including three genera that are key components of miombo savannas): the Berlinia clade. Our results indicate an asymmetric distribution of the capacity to shift and diversify into these biomes in Africa. Only five genera shifted between forest and savanna during the evolutionary history of the group, and only the first transitions in the early-middle Miocene in Julbernardia, Brachystegia, and Isoberlinia led to an increase in the number of species. This asymmetry is also evident from the distribution of species-rich lineages that exploited both biomes identified in this study (forest and savanna), as well as from the presence of five paleoendemic (mostly monotypic) genera that have persisted solely in the forest biome since the Eocene