Agradecimentos: We thank the curators and staff from the ESA, MO, NY and UEC herbaria for samples and IBAMA for collecting permits. We also thank MA Van Sluys for allowing us to use the infrastructure of the GaTE lab and TCS Corrêa for helping with cloning procedures. We thank members of the Lohmann and Antonelli research groups for fruitful discussions and suggestions. MFC was supported by a postdoctoral fellowship from the Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP 2009/52161-2; 2013/10262-2), a research grant from the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq 477267/2013-0) and Fundo de Apoio ao Ensino, à Pesquisa e à Extensão UNICAMP (Auxílio PAPDIC Convênio 519.292, n° 1412/15). VT was supported by a postdoctoral fellowship from the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES/PNPD) from the Programa de Pós-Graduação em Biologia Vegetal/UNICAMP. LGL thanks FAPESP for two regular research grants (2010/51755-3; 2011/50859-2) and a collaborative FAPESP/NSF/NASA grant on the ‘Assembly and evolution of the Amazonian biota and its environment’ (2012/50260-6) that funded all the field and molecular components of this project. Additional funds were provided by the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) through a Pq-1B grant to LGL (310871/2017-4) and a FAPESP Thematic Project (2018/23899-2). AA and CDB are supported by the Swedish Research Council (2019-05191 and 2017-04980 respectively), the Swedish Foundation for Strategic Research and the Royal Botanic Gardens, Kew to AA. D.S. received funding from the Swiss National Science Foundation (PCEFP3_187012) and from the Swedish Research Council (VR: 2019-04739). Finally, we thank one anonymous reviewer, Audrey Ragsac and Lars Chatrou for detailed and constructive comments Ver menos

Abstract: The biotic assembly of one of the most species-rich savannas, the Brazilian Cerrado, has involved recruitment of lineages from several surrounding regions. However, we lack a clear understanding about the timing and pathways of biotic exchanges among these regions and about the role those interchanges had in the assembly of Neotropical biodiversity. We investigated the timing and routes of species movements between wet or seasonally dry habitats across Neotropical regions and assessed the potential for ecological adaptation by evaluating the habitat transitions correlated with morphological shifts. Location Neotropics. Taxon the plant genus Anemopaegma (Bignonieae, Bignoniaceae). We inferred a Bayesian molecular phylogeny of Anemopaegma using one nuclear and two chloroplast markers. We sampled more than 90% of the known species diversity of Anemopaegma, covering its full geographical range. We estimated divergence times using a Bayesian relaxed-clock approach and inferred ancestral ranges as well as shifts in habitat and morphological characters. Phylogenetic analyses recovered seven main clades within Anemopaegma. The genus likely originated in Amazonia in the late Oligocene. Early-diverging lineages diversified in situ in Amazonia, particularly during the Miocene, with independent dispersal events to the Andes, Atlantic Forest and Cerrado. Shifts from seasonally dry forest to savanna habitats were correlated with shifts from liana to shrub and the loss of tendrils. The timing of diversification of major lineages within Anemopaegma is consistent with major geological and climatic events that occurred during the late Palaeogene and Neogene, such as the Andean uplift and the Middle Miocene Climatic Optimum. Movements across different regions within the Neotropics were relatively common but shifts between habitats were not. The correlation in the evolution of the shrubby habit, the loss of tendrils and the shifts from forest to savanna are consistent with a scenario of ecological adaptation Ver menos