title: The abiotic and biotic drivers of rapid diversification in Andean bellflowers (Campanulaceae).
abstract: The tropical Andes of South America, the world's richest biodiversity hotspot, are home to many rapid radiations. While geological, climatic, and ecological processes collectively explain such radiations, their relative contributions are seldom examined within a single clade. We explore the contribution of these factors by applying a series of diversification models that incorporate mountain building, climate change, and trait evolution to the first dated phylogeny of Andean bellflowers (Campanulaceae: Lobelioideae). Our framework is novel for its direct incorporation of geological data on Andean uplift into a macroevolutionary model. We show that speciation and extinction are differentially influenced by abiotic factors: speciation rates rose concurrently with Andean elevation, while extinction rates decreased during global cooling. Pollination syndrome and fruit type, both biotic traits known to facilitate mutualisms, played an additional role in driving diversification. These abiotic and biotic factors resulted in one of the fastest radiations reported to date: the centropogonids, whose 550 species arose in the last 5 million yr. Our study represents a significant advance in our understanding of plant evolution in Andean cloud forests. It further highlights the power of combining phylogenetic and Earth science models to explore the interplay of geology, climate, and ecology in generating the world's biodiversity.
authors.affiliation: Department of Organismic and Evolutionary Biology, Harvard University Herbaria, Harvard University, Cambridge, MA, 02138, USA.
authors.forename: Laura P
authors.initials: LP
authors.lastname: Lagomarsino
authors.affiliation: Department of Biological and Environmental Sciences, University of Gothenburg, Göteborg, SE 405 30, Sweden.
authors.forename: Fabien L
authors.initials: FL
authors.lastname: Condamine
authors.affiliation: Department of Biological and Environmental Sciences, University of Gothenburg, Göteborg, SE 405 30, Sweden.|Gothenburg Botanical Garden, Göteborg, SE 413 19, Sweden.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Antonelli
authors.affiliation: Senckenberg Biodiversity and Climate Research Centre (BiK-F), Senckenberg, Frankfurt/Main, 60325, Germany.|Institute for Geosciences, Goethe University Frankfurt, Frankfurt/Main, 60438, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Mulch
authors.affiliation: Department of Organismic and Evolutionary Biology, Harvard University Herbaria, Harvard University, Cambridge, MA, 02138, USA.
authors.forename: Charles C
authors.initials: CC
authors.lastname: Davis
mesh_terms: D044822:Biodiversity; D005075:Biological Evolution; D002980:Climate; D057231:Climate Change; D029745:Codonopsis / Q000033:anatomy & histology / Q000235:genetics* / Q000528:radiation effects; D004463:Ecology; D035264:Flowers / Q000033:anatomy & histology / Q000235:genetics / Q000528:radiation effects; D005844:Geology; D010802:Phylogeny; D054817:Pollination; D013020:South America
keywords: Andes; Lobelioideae; Neotropics; biodiversity hotspot; climate change; diversification; pollination syndromes; rapid radiation