## Comparisons in the native and introduced ranges reveal little evidence of climatic adaptation in germination traits Harold N. Eyster (1, 2, 3,*) and Elizabeth M. Wolkovich(2, 3, 4) \* Corresponding author haroldeyster@gmail.com 1. Institute for Resources, Environment, and Sustainability, University of British Columbia, 429-2202 Main Mall, Vancouver, BC, Canada V6T 1Z4 2. Arnold Arboretum of Harvard University, 1300 Centre Street, Boston, MA 02130, USA 3. Department of Organismic & Evolutionary Biology, Harvard University, 26 Oxford Street, Cambridge, MA 02138,USA 4. Department of Forest and Conservation Science, University of British Columbia, 3041-2424 Main Mall, Vancouver, BC, Canada V6T 1Z4 ### Repository information This repository is associated with the paper entitled "Comparisons in the native and introduced ranges reveal little evidence of climatic adaptation in germination traits" (Eyster and Wolkovich). It all the data and code needed to reproduce the statistical analyses, figures, and create the paper (with only minor non-scripted edits). ### License and citation information If you use the code or data provided here, please make sure to do so in light of the project license and please cite our work. We have provided citation guidelines for your reference. ### Paper abstract Plant invasions are increasing due to globalization and environmental change, including through anthropogenic climate change. Yet we lack an understanding of how some species become widespread invaders while others do not. Two competing mechanisms have been posited: 1) post-introduction rapid evolution to the novel environments of the introduced range and 2) broad environmental tolerance in the native population that makes invaders tolerant of diverse introduced environments. Each mechanism has implications for how invaders respond to climate change: either by evolving with future climates, or already being tolerant of diverse current/future climates. Disentangling these mechanisms requires investigating how evolution versus tolerance drive invasion traits (germination success and timing; growth rate). Here, we tested for evidence of rapid evolution in these traits by using growth chambers to provide common climates for seven herbaceous plant species sampled from multiple populations in their native (European) and introduced (North American) ranges. Chambers provided two levels of stratification---to simulate different winter lengths---and four temperature levels post-stratification---to simulate different spring conditions. We used Bayesian multilevel models to examine responses, while controlling for population and seed family. Across all species, trait responses were largely similar between native and introduced populations, except in response to particular climates representing cold winters and warm springs where introduced populations germinated later and grew faster. Our results suggest that broad environmental tolerance, not rapid evolution, likely underlies invasion success for these invaders---and may sustain their spread with continued warming---but species may evolve in response to specific combinations of winter and spring climatic regimes. ### Archive contents - src: all code, including data cleaning, data formatting, model fitting, and figure creation - germ_cleaning.R takes the raw data, cleans it, and produces cleaned data files. - unmodeled_plots.R takes the cleaned data and plots it (for the SI). - germ_rate_rstan.R takes the cleaned data and fits a Stan model for germination rate. - germ_timing_rstan.R takes the cleaned data and fits a Stan model for germination timing. - germ_growth_rstan.R takes the cleaned data and fits a Stan model for growth rate. - climate_germ.R processes data from WorldClim and computes the average temperature at each sampling location. - sampling_maps.R produces maps of sampling locations and plots the average temperatures at each. - germ_APC.Ris a function used to compute the Average Predictive Comparisons of the model parameters. - germ_APC_makefigure.R runs the germ_APC.R function on the model output and creates the APC figure in the manuscript. - plotting.R plots the model parameters. - PLALAN_plotting.R plots the model parameters for *Plantago lanceolata*. - germ_inter_fig.R plots the modeled interaction effects. - raw: the raw data in .csv format. - Germ_Data_2-9-16.csv contains the germination timing for each seed - Height_Data_2-13--16.csv contains the height data for each seed - id_Data-2-4-16.csv contains additional data on each seed (e.g., where it was collected). - label.csv contains data to help plot. - europe_lat_long.csv contains the latitude and longitude of European sampling locations. - US_lat_long.csv contains the latitude and longitude of American sampling locations. - clean contains processed data. - germs.rdatacontains cleaned data for germination rate and timing. - hlms.rdata contains cleaned data for growth rate. - gh.rdata contains cleaned data for seedling height. - out: output files, including from models. - rate_data.rdata is the formatted germination rate data. - time_data.rdata is the formatted germination timing data. - gr_data.rdata is the formatted growth rate data. - mod_rate.rdata is the rstanarm object containing MCMC model draws for germination rate. - mod_time.rdata is the rstanarm object containing MCMC model draws for germination timing. - mod_gr.rdata is the rstanarm object containing MCMC model draws for growth rate. - avg_temps.csv contains the average March, April, and May temperatures computed for each sampling location. - doc contains figures (in .svg and .pdf)as generated by scripts in src, occasionally with minor aesthetic edits in Inkscape. This folder also contains .bib files for creating the bibliographies in the main manuscript and the supplementary information, as well as R Sweave (.Rnw) and generated LaTeX documents (.tex) used to create the manuscript and supplementary information files (as .pdf files).