DOI: 10.5061/dryad.60p5d
title: Data from: Adaptive plasticity and niche expansion in an invasive thistle

description: Phenotypic differentiation in size and fecundity between native and
 invasive populations of a species has been suggested as a causal driver of
 invasion in plants. Local adaptation to novel environmental conditions
 through a micro-evolutionary response to natural selection may lead to
 phenotypic differentiation and fitness advantages in the invaded range.
 Local adaptation may occur along a stress tolerance trade-off, favoring
 individuals that, in benign conditions, shift resource allocation from
 stress tolerance to increased vigor and fecundity and, therefore,
 invasiveness. Alternately, the typically disturbed invaded range may
 select for a plastic, generalist strategy, making phenotypic plasticity
 the main driver of invasion success. To distinguish between these
 hypotheses, we performed a field common garden and tested for genetically
 based phenotypic differentiation, resource allocation shifts in response
 to water limitation, and local adaptation to the environmental gradient
 which describes the source locations for native and invasive populations
 of diffuse knapweed (Centaurea diffusa). Plants were grown in an
 experimental field in France (naturalized range) under water addition and
 limitation conditions. After accounting for phenotypic variation arising
 from environmental differences among collection locations, we found
 evidence of genetic variation between the invasive and native populations
 for most morphological and life-history traits under study. Invasive C.
 diffusa populations produced larger, later maturing, and therefore
 potentially fitter individuals than native populations. Evidence for local
 adaptation along a resource allocation trade-off for water limitation
 tolerance is equivocal. However, native populations do show evidence of
 local adaptation to an environmental gradient, a relationship which is
 typically not observed in the invaded range. Broader analysis of the
 climatic niche inhabited by the species in both ranges suggests that the
 physiological tolerances of C. diffusa may have expanded in the invaded
 range. This observation could be due to selection for plastic,
 “general-purpose” genotypes with broad environmental tolerances.
description: Bioclimatic data C.
 diffusa experimental populationsGeographic and climatic
 information for 14 sampled populations of native and invasive Centaurea
 diffusa (diffuse knapweed). Also, first three principal components from an
 analysis of this data.FrbioclimPCA_DKdat.txtPlanting information C. diffusa experimental plantsPlanting information for experimental Centaurea diffusa plantsFrdes.txtOccurrence records C. diffusaRecords of Centaurea diffusa in Europe and North America, from GBIF.org, downloaded January 9, 2015Cdif_GBIF_allocc.txtLocation information for collected C. diffusa populationsLocation and collection information for populations of native and invasive Centaurea diffusa (diffuse knapweed) used in the experimental PCA and occurrence PCA.Popcoord.txtAdjusted location information for collected C. diffusa populationsAdjusted location and collection information for populations of native and invasive Centaurea diffusa (diffuse knapweed) used in the experimental PCA and occurrence PCA.Popcoord_worldclim.txtBioclimatic data for C. diffusa occurrencesBioclimatic data and PCA values for occurrence records of Centaurea diffusa Geographic and climatic information for 662 occurrence records of native and invasive Centaurea diffusa (diffuse knapweed) from North America and Europe. Occurrence records include records from GBIF.org as well as collected populations.Cdif_allocc_bioclimPCA.txtTrait data at harvest, from C. diffusa common gardenTrait data for experimental populations of Centaurea diffusa, measured at harvest. Trait values measured in common field experiment in Montpellier, France, 2011. File also include the first three principal components from the experimental PCA of the bioclimatic data for these populations.FrTraitClimDat_cline.txtPhenological trait data, from C. diffusa common gardenPhenological trait data for experimental populations of Centaurea diffusa, measured throughout experiment Trait values measured in common field experiment in Montpellier, France, 2011. File also include the first three principal components from the experimental PCA of the bioclimatic data for these populations.FrEnd_cline.txtRepeated measures of traits, from C. diffusa common gardenTrait data for experimental populations of Centaurea diffusa, repeated measures. Trait values measured in common field experiment in Montpellier, France, 2011. File also include the first three principal components from the experimental PCA of the bioclimatic data for these populations.FrTraitClimDat_cline_long.txtFranceCG - codeGithub repository storing R scripts used in this paper.