title: Division of Labor Brings Greater Benefits to Clones of Carpobrotus edulis in the Non-native Range: Evidence for Rapid Adaptive Evolution.
abstract: Why some species become invasive while others do not is a central research request in biological invasions. Clonality has been suggested as an attribute that could contribute to plant invasiveness. Division of labor is an important advantage of clonal growth, and it seems reasonable to anticipate that clonal plants may intensify this clonal attribute in an invaded range because of positive selection on beneficial traits. To test this hypothesis, we collected clones of Carpobrotus edulis from native and invasive populations, grew pairs of connected and severed ramets in a common garden and under negative spatial covariance of nutrients and light to induce division of labor, and measured biomass allocation ratios, final biomass, and photochemical efficiency. Our results showed that both clones from the native and invaded range develop a division of labor at morphological and physiological level. However, the benefit from the division of labor was significantly higher in apical ramets from the invaded range than in ramets from the native area. This is a novel and outstanding result because it provides the first evidence that the benefit of a key clonal trait such as division of labor may have been subjected to evolutionary adaptation in the invaded range. The division of labor can therefore be considered an important trait in the invasiveness of C. edulis. An appropriate assessment of the influence of clonal traits in plant invasions seems key for understanding the underlying mechanisms behind biological invasions of new environments.
authors.affiliation: BioCost Group, Department of Animal Biology, Plant Biology and Ecology, Faculty of Science, University of A Coruña Spain.
authors.forename: Sergio R
authors.initials: SR
authors.lastname: Roiloa
authors.affiliation: Unit of Ecology, Faculty of Biology, University of Santiago de Compostela Santiago de Compostela, Spain.
authors.forename: Rubén
authors.initials: R
authors.lastname: Retuerto
authors.affiliation: Unit of Ecology, Faculty of Biology, University of Santiago de Compostela Santiago de Compostela, Spain.
authors.forename: Josefina G
authors.initials: JG
authors.lastname: Campoy
authors.affiliation: Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch UniversityMatieland, South Africa; Invasive Species Programme, South African National Biodiversity Institute, Kirstenbosch Research CentreClaremont, South Africa.
authors.forename: Ana
authors.initials: A
authors.lastname: Novoa
authors.affiliation: BioCost Group, Department of Animal Biology, Plant Biology and Ecology, Faculty of Science, University of A Coruña Spain.
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Barreiro
keywords: Carpobrotus edulis; biological invasions; biomass allocation; chlorophyll fluorescence; clonal integration; division of labor; local adaptation; spectral reflectance