Léa Bardon1, Cynthia Sothers2, Ghillean T Prance2, Pierre-Jean G Malé3, Zhenxiang Xi4, Charles C Davis4, Jerome Murienne1, Roosevelt García-Villacorta5, Eric Coissac6, Sébastien Lavergne6, Jérôme Chave7. 1. Laboratoire Evolution et Diversité Biologique UMR 5174 CNRS, ENFA, Université Paul Sabatier 31062 Toulouse, France. 2. Herbarium, Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AB, United Kingdom. 3. Department of Ecology and Evolutionary Biology, University of Toronto, Ontario, Canada. 4. Department of Organismic and Evolutionary Biology, Harvard University Herbaria, 22 Divinity Avenue, Cambridge, Massachusetts 02138, USA. 5. Royal Botanic Garden Edinburgh, 20a Inverleith Row Edinburgh EH3 5LR, United Kingdom. 6. Université Grenoble Alpes, CNRS, UMR 5553 LECA, F-38000 Grenoble, France. 7. Laboratoire Evolution et Diversité Biologique UMR 5174 CNRS, ENFA, Université Paul Sabatier 31062 Toulouse, France jerome.chave@univ-tlse3.fr.
Abstract
PREMISE OF THE STUDY: The complex geological and climatic history of the Neotropics has had major implications on the diversification of plant lineages. Chrysobalanaceae is a pantropical family of trees and shrubs with 75% of its 531 species found in the Neotropics, and a time-calibrated phylogeny of this family should shed light on the tempo of diversification in the Neotropical flora. Previously published phylogenetic hypotheses of this family were poorly supported, and its biogeography remains unclear. METHODS: We assembled the complete plastid genome of 51 Chrysobalanaceae species, and increased taxon sampling by Sanger-sequencing of five plastid regions for an additional 88 species. We generated a time-calibrated tree including all 139 Chrsyobalanaceae species and 23 outgroups. We then conducted an ancestral area reconstruction analysis and estimated diversification rates in the family. KEY RESULTS: The tree generated with the plastid genome alignment was almost fully resolved. It supports the polyphyly of Licania and Hirtella. The family has diversified starting around the Eocene-Oligocene transition. An ancestral area reconstruction confirms a Paleotropical origin for Chrysobalanaceae with several transoceanic dispersal events. The main Neotropical clade likely resulted from a single migration event from Africa around 28 mya ago, which subsequently underwent rapid diversification. CONCLUSIONS: Given the diverse ecologies exhibited by extant species, we hypothesize that the rapid diversification of Chrysobalanaceae following the colonization of the Neotropics was triggered by habitat specialization during the complex geological and paleoclimatic history of the Neotropics.
PREMISE OF THE STUDY: The complex geological and climatic history of the Neotropics has had major implications on the diversification of plant lineages. Chrysobalanaceae is a pantropical family of trees and shrubs with 75% of its 531 species found in the Neotropics, and a time-calibrated phylogeny of this family should shed light on the tempo of diversification in the Neotropical flora. Previously published phylogenetic hypotheses of this family were poorly supported, and its biogeography remains unclear. METHODS: We assembled the complete plastid genome of 51 Chrysobalanaceae species, and increased taxon sampling by Sanger-sequencing of five plastid regions for an additional 88 species. We generated a time-calibrated tree including all 139 Chrsyobalanaceae species and 23 outgroups. We then conducted an ancestral area reconstruction analysis and estimated diversification rates in the family. KEY RESULTS: The tree generated with the plastid genome alignment was almost fully resolved. It supports the polyphyly of Licania and Hirtella. The family has diversified starting around the Eocene-Oligocene transition. An ancestral area reconstruction confirms a Paleotropical origin for Chrysobalanaceae with several transoceanic dispersal events. The main Neotropical clade likely resulted from a single migration event from Africa around 28 mya ago, which subsequently underwent rapid diversification. CONCLUSIONS: Given the diverse ecologies exhibited by extant species, we hypothesize that the rapid diversification of Chrysobalanaceae following the colonization of the Neotropics was triggered by habitat specialization during the complex geological and paleoclimatic history of the Neotropics.
Authors: Ricardo A Segovia; R Toby Pennington; Tim R Baker; Fernanda Coelho de Souza; Danilo M Neves; Charles C Davis; Juan J Armesto; Ary T Olivera-Filho; Kyle G Dexter Journal: Sci Adv Date: 2020-05-06 Impact factor: 14.136