title: Tectonic-driven climate change and the diversification of angiosperms.
abstract: In 1879, Charles Darwin characterized the sudden and unexplained rise of angiosperms during the Cretaceous as an "abominable mystery." The diversification of this clade marked the beginning of a rapid transition among Mesozoic ecosystems and floras formerly dominated by ferns, conifers, and cycads. Although the role of environmental factors has been suggested [Coiffard C, Gómez B (2012) Geol Acta 10(2):181-188], Cretaceous global climate change has barely been considered as a contributor to angiosperm radiation, and focus was put on biotic factors to explain this transition. Here we use a fully coupled climate model driven by Mesozoic paleogeographic maps to quantify and discuss the impact of continental drift on angiosperm expansion and diversification. We show that the decrease of desertic belts between the Triassic and the Cretaceous and the subsequent onset of long-lasting humid conditions during the Late Cretaceous were driven by the breakup of Pangea and were contemporaneous with the first rise of angiosperm diversification. Positioning angiosperm-bearing fossil sites on our paleobioclimatic maps shows a strong match between the location of fossil-rich outcrops and temperate humid zones, indicating that climate change from arid to temperate dominance may have set the stage for the ecological expansion of flowering plants.
authors.affiliation: Laboratoire des Sciences du Climat et de l'Environnement, Unité Mixte, Centre National de la Recherche Scientifique-Commissariat à l'Energie Atomique-Université de Versailles Saint-Quentin-en-Yvelines, 91191 Gif-sur-Yvette, France; and aclairecha@hotmail.com.
authors.forename: Anne-Claire
authors.initials: AC
authors.lastname: Chaboureau
authors.affiliation: Laboratoire des Sciences du Climat et de l'Environnement, Unité Mixte, Centre National de la Recherche Scientifique-Commissariat à l'Energie Atomique-Université de Versailles Saint-Quentin-en-Yvelines, 91191 Gif-sur-Yvette, France; and.
authors.forename: Pierre
authors.initials: P
authors.lastname: Sepulchre
authors.affiliation: Laboratoire des Sciences du Climat et de l'Environnement, Unité Mixte, Centre National de la Recherche Scientifique-Commissariat à l'Energie Atomique-Université de Versailles Saint-Quentin-en-Yvelines, 91191 Gif-sur-Yvette, France; and.
authors.forename: Yannick
authors.initials: Y
authors.lastname: Donnadieu
authors.affiliation: Unité Mixte de Recherche Biodiversité, Gènes et Communautés, Institut National de la Recherche Agronomique, 33612 Cestas, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Franc
mesh_terms: D005075:Biological Evolution; D057231:Climate Change; D017753:Ecosystem; D005580:Fossils; D049810:Genetic Speciation; D014644:Genetic Variation; D049690:History, Ancient; D019684:Magnoliopsida / Q000145:classification / Q000235:genetics; D008954:Models, Biological; D010163:Paleontology
keywords: climate modeling; paleogeography