title: Self-compatibility is over-represented on islands.
abstract: Because establishing a new population often depends critically on finding mates, individuals capable of uniparental reproduction may have a colonization advantage. Accordingly, there should be an over-representation of colonizing species in which individuals can reproduce without a mate, particularly in isolated locales such as oceanic islands. Despite the intuitive appeal of this colonization filter hypothesis (known as Baker's law), more than six decades of analyses have yielded mixed findings. We assembled a dataset of island and mainland plant breeding systems, focusing on the presence or absence of self-incompatibility. Because this trait enforces outcrossing and is unlikely to re-evolve on short timescales if it is lost, breeding system is especially likely to reflect the colonization filter. We found significantly more self-compatible species on islands than mainlands across a sample of > 1500 species from three widely distributed flowering plant families (Asteraceae, Brassicaceae and Solanaceae). Overall, 66% of island species were self-compatible, compared with 41% of mainland species. Our results demonstrate that the presence or absence of self-incompatibility has strong explanatory power for plant geographical patterns. Island floras around the world thus reflect the role of a key reproductive trait in filtering potential colonizing species in these three plant families.
authors.affiliation: Department of Biology, California Polytechnic State University, San Luis Obispo, CA, 93407, USA.|Department of Plant and Microbial Biology, University of Minnesota, Saint Paul, MN, 55108, USA.|School of Biological Sciences, Washington State University, Pullman, WA, 99164, USA.
authors.forename: Dena L
authors.initials: DL
authors.lastname: Grossenbacher
authors.affiliation: Department of Plant and Microbial Biology, University of Minnesota, Saint Paul, MN, 55108, USA.
authors.forename: Yaniv
authors.initials: Y
authors.lastname: Brandvain
authors.affiliation: Department of Biology, West Chester University, West Chester, PA, 19383, USA.
authors.forename: Josh R
authors.initials: JR
authors.lastname: Auld
authors.affiliation: School of Biological Sciences, Monash University, Melbourne, VIC, 3800, Australia.
authors.forename: Martin
authors.initials: M
authors.lastname: Burd
authors.affiliation: CEFE UMR 5175, CNRS, Université de Montpellier, Université Paul-Valery Montpellier, EPHE, CEFE, 34293, Montpellier Cedex 05, France.
authors.forename: Pierre-Olivier
authors.initials: PO
authors.lastname: Cheptou
authors.affiliation: Kellogg Biological Station and Department of Plant Biology, Michigan State University, Hickory Corners, MI, 49060, USA.
authors.forename: Jeffrey K
authors.initials: JK
authors.lastname: Conner
authors.affiliation: Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN, 37996, USA.
authors.forename: Alannie G
authors.initials: AG
authors.lastname: Grant
authors.affiliation: Department of Evolution, Ecology, and Organismal Biology, Ohio State University, Columbus, OH, 43210, USA.
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Hovick
authors.affiliation: Department of Ecology and Evolution, University of Lausanne, 1015, Lausanne, Switzerland.
authors.forename: John R
authors.initials: JR
authors.lastname: Pannell
authors.affiliation: Department of Botany and Zoology, Stellenbosch University, Stellenbosch, 7602, South Africa.
authors.forename: Anton
authors.initials: A
authors.lastname: Pauw
authors.affiliation: Laboratory of Biogeography and Ecology, Department of Geography, University of the Aegean, 81100, Mytilene, Lesvos, Greece.
authors.forename: Theodora
authors.initials: T
authors.lastname: Petanidou
authors.affiliation: Department of Environmental Science, University of San Francisco, San Francisco, CA, 94117, USA.
authors.forename: April M
authors.initials: AM
authors.lastname: Randle
authors.affiliation: Departmento Ecología, Facultad de Ciencias, Universidad de Granada, Granada, UGR, 18071, Granada, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: Rubio de Casas
authors.affiliation: Department of Biological Sciences, University of Calgary, Calgary, AB, Canada, T2N 1N4.
authors.forename: Jana
authors.initials: J
authors.lastname: Vamosi
authors.affiliation: Department of Biological Science, Florida State University, Tallahassee, FL, 32306, USA.
authors.forename: Alice
authors.initials: A
authors.lastname: Winn
authors.affiliation: Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL, 60607, USA.
authors.forename: Boris
authors.initials: B
authors.lastname: Igic
authors.affiliation: School of Biological Sciences, Washington State University, Pullman, WA, 99164, USA.
authors.forename: Jeremiah W
authors.initials: JW
authors.lastname: Busch
authors.affiliation: Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN, 37996, USA.
authors.forename: Susan
authors.initials: S
authors.lastname: Kalisz
authors.affiliation: Department of Ecology, Evolution, and Behavior, University of Minnesota, Saint Paul, MN, 55108, USA.
authors.forename: Emma E
authors.initials: EE
authors.lastname: Goldberg
mesh_terms: D019659:Asteraceae / Q000502:physiology*; D019607:Brassicaceae / Q000502:physiology*; D062312:Islands; D012100:Reproduction, Asexual; D019657:Solanaceae / Q000502:physiology*
keywords: Baker's law; biogeography; ecological filtering; island; mainland; self-incompatibility