title: High functional diversity stimulates diversification in experimental microbial communities.
abstract: There is a growing awareness that biodiversity not only drives ecosystem services but also affects evolutionary dynamics. However, different theories predict contrasting outcomes on when do evolutionary processes occur within a context of competition. We tested whether functional diversity can explain diversification patterns. We tracked the survival and diversification of a focal bacterial species (Pseudomonas fluorescens) growing in bacterial communities of variable diversity and composition. We found that high functional diversity reduced the fitness of the focal species and, at the same time, fostered its diversification. This pattern was linked to resource competition: High diversity increased competition on a portion of the resources while leaving most underexploited. The evolved phenotypes of the focal species showed a better use of underexploited resources, albeit at a cost of lower overall growth rates. As a result, diversification alleviated the impact of competition on the fitness of the focal species. We conclude that biodiversity can stimulate evolutionary diversification, provided that sufficient alternative niches are available.
authors.affiliation: J.F. Blumenbach Institute of Zoology and Anthropology, Georg August University Göttingen, Berliner Straße 28, 37073 Göttingen, Germany.; Institute of Environmental Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht, Netherlands.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Jousset
authors.affiliation: German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, 04103 Leipzig, Germany.; Institute of Biology, Leipzig University, Johannisallee 21, 04103 Leipzig, Germany.
authors.forename: Nico
authors.initials: N
authors.lastname: Eisenhauer
authors.affiliation: J.F. Blumenbach Institute of Zoology and Anthropology, Georg August University Göttingen, Berliner Straße 28, 37073 Göttingen, Germany.
authors.forename: Monika
authors.initials: M
authors.lastname: Merker
authors.affiliation: Institut des Sciences de l'Evolution, UMR 5554, CNRS, Université Montpellier 2, CC 065, Place Eugène Bataillon, 34095 Montpellier, Cedex 05, France.; MARBEC, UMR IRD-CNRS-UM-IFREMER 9190, Université Montpellier, CC 093, FR-34095 Montpellier, Cedex 5, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Mouquet
authors.affiliation: J.F. Blumenbach Institute of Zoology and Anthropology, Georg August University Göttingen, Berliner Straße 28, 37073 Göttingen, Germany.
authors.forename: Stefan
authors.identifier: 0000-0003-4350-9520
authors.initials: S
authors.lastname: Scheu
mesh_terms: D001419:Bacteria; D044822:Biodiversity; D005075:Biological Evolution; D017753:Ecosystem; D056084:Genetic Fitness; D005838:Genotype; D010641:Phenotype; D011995:Recombination, Genetic; D012641:Selection, Genetic
keywords: Biodiversity; adaptive radiation; competition; experimental evolution; trade-offs