DOI: 10.5061/dryad.v6wwpzh30
title: Competitors alter selection on alpine plants exposed to experimental climate change

description: Investigating how climate change alters selection regimes is a crucial
 step towards understanding the potential of populations to evolve in the
 face of changing conditions. Previous studies have mainly focused on
 understanding how changing climate directly influences selection, while
 the role of species’ interactions has received little attention. Here, we
 used a transplant experiment along an elevation gradient to estimate how
 climate warming and competitive interactions lead to shifts in directional
 phenotypic selection on morphology and phenology of four alpine plants. We
 found that warming generally imposed novel selection, with the largest
 shifts in regimes acting on specific leaf area and flowering time across
 species. Competitors instead weakened the selection acting on traits that
 was imposed directly by warming. Weakened or absent selection in the
 presence of competitors was largely associated with the suppression of
 absolute means and variation of fitness. Our results suggest that although
 climate change can impose strong selection, competitive interactions
 within communities might act to limit selection and thereby stymie
 evolutionary responses in alpine plants facing climate change.
description: # Competitors alter selection on alpine plants exposed to experimental
 climate change The data
 derives from a transplant experiment performed along an elevation gradient
 in Switzerland from 2016-2019, where four alpine plant species where
 transplanted from high (2200) to three lower elevations either in the
 absence or presence of competitors. The dataset includes traits (stalk
 height, specific leaf area, flowering time and floral size) as well as
 information on survival, seed production and flowering for individuals
 across the experiment. ## Description of the data and file structure
 Explanation of columns in dataset: * Column "Site" includes data
 on the experimental site to which plants were transplanted. "P"
 = 1400 m a.s.l., "M" = 1750 m a.s.l., "C" = 1950 m
 a.s.l. and "R" = 2200 m a.s.l. * Column "Block"
 includes data on the experimental block to which plants were transplanted
 within each site (1-10) * Column "Competition" includes data on
 the competitor treatment. "No_competition" = Competitors absent,
 "Competition" = Competitors present * Column "Species"
 includes data on the focal species. "ant" = Anthyllis
 vulneraria, "tri" = Trifolium badium, "pla" = Plantago
 alpina, "cam" = Campanula scheuchzeri * Columns
 "survival_xx" includes data on survival estimated 2017-2019
 (1=alive, 0=dead) * Columns "flowering_xx" includes data on
 flowering estimated 2017-2019 (1=flowering, 0=not flowering) * Columns
 "seed_xx" includes data on estimated seed production estimated
 2017-2019 (number of seeds) * Column "F_TIME" includes data on
 flowering time (julian day) across 2017-2019 * Column "F_SIZE"
 includes data on banner size across 2017-2019 (millimeters) * Column
 "FHLM" includes data on floral length across 2017-2019
 (millimeters) * Column "FHWM" includes data on floral width
 across 2017-2019 (millimeters) * Column "S_HEIGHT" includes data
 on stalk height across 2017-2019 (millimeters) * Column "L_NO"
 includes data on leaf number across 2017-2019 * Column "SLA"
 includes data on SLA across 2017-2019 (millimeters/g) * NA values
 represents missing data that were be obtained during data collection ##
 Code/Software The analyses are presented in the following scripts: 1.
 Obtaining fitness ("1_Obtaining fitness.R") 2. Identifying Most
 Parsimonious Models (MPMs; "2_Identifying_MPMs.R") 3. Estimating
 selection for Anthyllis vulneraria
 ("3_Estimating_selection_ant.R") 4. Estimating selection for
 Trifolium badium ("3_Estimating_selection_tri.R") 5. Estimating
 selection for Plantago alpina ("3_Estimating_selection_pla.R")
 6. Estimating selection for Campanula scheuchzeri
 ("3_Estimating_selection_cam.R") 7. Estimating fitness and trait
 means ("4_Estimating_fitness_trait_means.R") 8. Estimating
 fitness and trait variation
 ("5_Estimating_fitness_trait_variation.R") All steps of these
 analyses are described in the main text of the paper "Competitors
 alter selection on alpine plants exposed to experimental climate
 change" in Evolution Letters.