DOI: 10.5061/dryad.x3ffbg7z4
title: Variation in response to water availability across Phlox species

description: Plants adapt to environmental variation both by evolving divergent trait
 means and by plastically adjusting trait expression in response to local
 conditions. While these dual strategies are essential for persistence in
 diverse environments, how they interact and vary across closely related
 species is understudied. For plants, water availability is a particularly
 important selective force that shapes species distributions, selects for
 growth habit and life history strategy, and can dictate individuals’
 plastic expressions of trait values and reproductive success. Here, we use
 ecological niche modeling, field soil collections, and a controlled
 drought experiment to test how biogeography and evolutionary history
 influence responses to limited water availability in three closely related
 Texas annual Phlox species and their F1 hybrids. We
 infer that the species occupy distinct niches that diverge along a primary
 axis of water availably and soil moisture. Each species has a distinct
 vegetative growth habit that does not match broad predictions of
 divergence in response to water availability. Nevertheless, we find that
 all the species show a significant morphological response to controlled
 soil dry down with reduced biomass, smaller leaves, and fewer flowers, as
 would be predicted in a response to drought. We find that Phlox
 drummondii, which occupies intermediate habitats, exhibits the strongest
 plastic response to water limitation, despite it not having the broadest
 environmental niche. Additionally, most hybrids involving P.
 drummondii display intermediate phenotypes in both wet and dry
 treatments, while hybrids between P.
 cuspidata and P. roemeriana show phenotypes
 consistent with hybrid vigor. These results challenge the hypothesis that
 species from broader environments evolve greater plasticity. Instead, the
 most plastic species did not have the broadest niche, suggesting
 plasticity and niche breadth may evolve independently.
description: # Reference Information ## Provenance for this README * File name:
 README.md * Authors: Christina Steinecke, Julius A. Tabin * Date created:
 2025-05-30 * Date most recently modified: 2025-06-03 ## Dataset Version
 and Release History * Current Version: * Number: 1.0.1 * Date: 2025-10-18
 * Persistent identifier: DOI: 10.5061/dryad.x3ffbg7z4 * Summary of
 changes: Compiled for the first time * Embargo Provenance: n/a * Scope of
 embargo: n/a * Embargo period: n/a ## Dataset Attribution and Usage *
 Dataset Title: Data for the article "Variation in response to water
 availability across Phlox species" * Persistent Identifier: [DOI:
 10.5061/dryad.x3ffbg7z4](10.5061/dryad.x3ffbg7z4) * Dataset Contributors:
 * Creators: Christina Steinecke, Julius A. Tabin, James Caven, Charlie O.
 Hale, Antonio Serrato-Capuchina, and Robin Hopkins * Date of Issue:
 2025-05-30 * License: Use of these data from Zenodo is covered by the
 following license: * Title: GNU General Public License v3.0 *
 Specification:
 [https://www.gnu.org/licenses/gpl-3.0.en.html](https://www.gnu.org/licenses/gpl-3.0.en.html) * License: Use of these data from Dryad is covered by the following license: * Title: CC0 1.0 Universal (CC0 1.0) * Specification: [https://creativecommons.org/publicdomain/zero/1.0/](https://creativecommons.org/publicdomain/zero/1.0/) * Data Reuse * The authors respectfully request to be contacted by researchers interested in the reuse of these data so that the possibility of collaboration can be discussed. * Suggested Citations: * Dataset citation: &gt; Christina S., Tabin J.A., Caven J., Hale C.O., Serrato-Capuchina A., and Hopkins, R. 2025. Data for the article "Species-level variation in ecophysiology and plastic response to drought in annual Phlox", Dryad, Dataset, [DOI: 10.5061/dryad.x3ffbg7z4](10.5061/dryad.x3ffbg7z4) * Corresponding publication: &gt; Christina S., Tabin J.A., Caven J., Hale C.O., Serrato-Capuchina A., and Hopkins, R. 2025. "Species-level variation in ecophysiology and plastic response to drought in annual Phlox". Plant-Environment Interactions. Submitted. ## Contact Information * Name: Christina Steinecke * Affiliations: Department of Organismic and Evolutionary Biology, Harvard University * ORCID ID: [https://orcid.org/0000-0001-7946-5369](https://orcid.org/0000-0001-7946-5369) * Email: [christinasteinecke@g.harvard.edu](mailto:christinasteinecke@g.harvard.edu) * Alternate Email: [christinasteinecke@fas.harvard.edu](mailto:christinasteinecke@fas.harvard.edu) * Address: e-mail preferred * Name: Julius A. Tabin * Affiliations: Department of Organismic and Evolutionary Biology, Harvard University * ORCID ID: [https://orcid.org/0000-0002-3591-6620](https://orcid.org/0000-0002-3591-6620) * Email: [jtabin1@gmail.com](mailto:jtabin1@gmail.com) * Alternate Email: [jtabin@g.harvard.edu](mailto:jtabin@g.harvard.edu) * Address: e-mail preferred * Contributor ORCID IDs: * Julius A. Tabin: [https://orcid.org/0000-0002-3591-6620](https://orcid.org/0000-0002-3591-6620) * Christina Steinecke: [https://orcid.org/0000-0001-7946-5369](https://orcid.org/0000-0001-7946-5369) * Charles O. Hale: [https://orcid.org/0000-0001-8119-5273](https://orcid.org/0000-0001-8119-5273) * Antonio Serrato-Capuchina: [[https://orcid.org/0000-0002-7819-6053](https://orcid.org/0000-0002-7819-6053)] ([https://orcid.org/0000-0002-7819-6053](https://orcid.org/0000-0002-7819-6053)) * Robin Hopkins: [https://orcid.org/0000-0002-6283-4145](https://orcid.org/0000-0002-6283-4145) --- # Additional Dataset Metadata ## Acknowledgements * Funding sources: This work was supported by grants from NSF DEB-1844906 and NIH 1R35GM142742. J.C. was supported by the Herchel Smith Undergraduate Science Research Program of Harvard University and the Harvard College Research Program. * Formatting for this README file is based on the README file of LaPergola, J.B., C. Riehl, J.E. Martínez-Gómez, B. Roldán-Clarà, and R.L. Curry. 2022. Data for the article "Extra-pair paternity correlates with genetic diversity, but not breeding density, in a Neotropical passerine, the Black Catbird", Dryad, Dataset, [https://doi.org/10.5061/dryad.2bvq83btg](https://doi.org/10.5061/dryad.2bvq83btg) --- # Methodological Information * Methods of data collection/generation: see manuscript for details --- # Data and File Overview ## Summary Metrics * File count: 7 * Range of individual file sizes: 16.0 KB - 3.6 MB * File formats: .csv, .Rmd, .R, .ipynb ## Table of Contents * Niche_modelling.R * Drydown_stats.Rmd * Drydown_plots.ipynb * Enviro_PCA.ipynb * Texas_Phlox_Triad.csv * totalsoil.csv * drydown2021_data.csv ## Setup * Unpacking instructions: n/a * Recommended software/tools: Python version 3.11.6; RStudio 2021.05.24; R version 4.2.1 ## Notes * All cells left empty in any data file are because there is no data present there for that individual. The programs for analyzing the data have been designed with these gaps in mind and the gaps are intentional; data is not missing. --- # File Details ## Details for: Niche_modelling.R * Description: an R file containing code for taking Phlox geolocation data (provided in "Texas_Phlox_Triad.csv") and creating a niche model, as well as representative figures. * Format(s): .R ## Details for: Drydown_stats.Rmd * Description: an R Markdown file containing code for taking measurements from this work's drydown experiment (provided in "drydown2021_data.csv"), creating linear mixed models, generating plots, and performing statistical comparisons between the models, as well as between specific groups. * Format(s): .Rmd ## Details for: Drydown_plots.ipynb * Description: a Jupyter Notebook file containing code to take measurements from this work's drydown experiment (provided in "drydown2021_data.csv") as its input, outputting dimensionality reduction (UMAP/PCA) plots. * Format(s): .ipynb ## Details for: Enviro_PCA.ipynb * Description: a Jupyter Notebook file containing code to take measures of soil characteristics of wild Phlox (provided in "totalsoil.csv"), resulting in dimensionality reduction (PCA) plots. * Format(s): .ipynb ## Details for: Texas_Phlox_Triad.csv * Description: a comma-delimited file containing the geolocations of Phlox species. * Format(s): .csv * Variables: * Species: the species of the assessed Phlox * Latitude: the latitude of the location in which that individual was found. * Longitude: the longitude of the location in which that individual was found. * Source: the source of the latitude and longitude information, either the Hopkins lab or the Global Biodiversity Information Facility (GBIF) ## Details for: totalsoil.csv * Description: a comma-delimited file containing the soil measurements around the locations of wild Phlox species. Samples were collected over a single week in May 2023. Results were determined by direct sampling and the Soil, Water, and Forage Testing Laboratory at Texas A&M AgriLife (College Station, TX). Each row represents on individual core. * Format(s): .csv * Variables: * Species: the species of the assessed Phlox (drumm = P. drummondii, cusp = P. cuspidata, roem = P. roemeriana, villo = P. villosissima, pilosa = P. pilosa) * site_ID: the ID of the site visited (determined based on the letter of the species that is present in that area) * location_north: the latitude of the location in which that individual was found. * location_west: the longitude of the location in which that individual was found. * soil_moisture: soil moisture in parts per million * soil_temp: soil temperature in Fahrenheit * soil_conduct: soil conductivity in milliSiemens per meter * Cond_umhos.cm: soil conductivity in Micromhos per centimeter * NO3N_ppm: soil concentration of nitrate nitrogen in parts per million * P_ppm: soil concentration of phosphorus in parts per million * K_ppm: soil concentration of potassium in parts per million * Ca_ppm: soil concentration of calcium in parts per million * Mg_ppm: soil concentration of magnesium in parts per million * S_ppm: soil concentration of sulfur in parts per million * Na_ppm: soil concentration of sodium in parts per million * Fe_ppm: soil concentration of iron in parts per million * Zn_ppm: soil concentration of zinc in parts per million * Mn_ppm: soil concentration of manganese in parts per million * Cu_ppm: soil concentration of copper in parts per million * B_ppm: soil concentration of boron in parts per million * Sand_.: percentage of soil composed of sand * Silt_.: percentage of soil composed of silt * Clay_.: percentage of soil composed of clay * textural_class: soil textural class, as defined by the United States Department of Agriculture (USDA), based on sand, silt, and clay composition * Organic_Carbon_.: soil concentration of organic carbon in parts per million ## Details for: drydown2021_data.csv * Description: a comma-delimited file containing the information and measurements for the drydown experiment described in Steinecke and Tabin et al. 2025. * Format(s): .csv * Variables: * pot.id: the lab-defined pot number that the plant was raised in * cross.id: the lab-defined id numbers for the parents of the individual, separated by an x * well.id: the lab-defined id number for the germination well that the individual was assigned to * alive: whether the germinant survived (1) or died (0) * cohort: the lab-defined cohort that the individual was assigned to * germination.date: days since the start of the experiment that the individual germinated * transplant.date: days since the start of the experiment that the individual was transplanted * treatment.start.date: days since the start of the experiment that the treatment was applied * treatment: whether the plant was assigned to the wet or dry experimental condition * dry.weight: the weight in grams of the plant after transplanting into a new pot with dry soil * wet.weight the weight in grams of the plant after transplanting into a new pot and adding water * target.weight: the weight necessary for each treatment * stake.weight: the weight of the 4 wooden stakes used to maintain plant stature * preweight.X.XX: the numbers in the column name represent the date on which the measurement was taken * flowering.date: days since the start of the experiment of plant flowering, if the plant flowered during the experiment * death.date: days since the start of the experiment of plant death, if the plant died during the experiment * fourweek.leaf.count: number of leaves four weeks into the experiment * fourweek.leaf.length: longest leaf length in cm four weeks into the experiment * petal1.length: petal length in cm at the end of experiment * petal2.length: petal length in cm at the end of experiment * corolla1.length: corolla length in cm at the end of experiment * corolla2.length: corolla length in cm at the end of experiment * flower1.area: flower area in cm^2 at the end of experiment * flower2.area: flower area in cm^2 at the end of experiment * end.biomass.fresh: fresh biomass in grams at the end of experiment * end.height: plant height in cm at the end of experiment * end.length.leaf1: longest leaf length in cm at the end of experiment * end.length.leaf2: longest leaf length in cm at the end of experiment * end.flower.count: number of flowers at the end of experiment * end.leaf.count: number of leaves at the end of experiment * end.biomass.dry: dry biomass in grams at the end of experiment * species: which species (drum = P. drummondii, cusp = P. cuspidata, roem = P. roemeriana) or hybrid the individual is * Notes: any experimental notes * survived: whether (1) or not (0) the plant survived * mat.id: the lab-given id number for the maternal parent. The id is composed of three parts (XXX-YY-Z): XXX population, YY family, Z individual * mat.pop: the lab-given number for the maternal parent's population (XXX) * pat.id: the lab-given id number for the paternal parent. The id is composed of three parts (XXX-YY-Z): XXX population, YY family, Z individual * pat.pop: the lab-given number for the paternal parent's population (XXX) * mat.lat: the latitude of the maternal parent * pat.lat: the latitude of the paternal parent * mat.long: the longitude of the maternal parent * pat.long: the longitude of the paternal parent * mat.zone: whether the maternal parent was from an allopatric location (allo) or a location that multiple species inhabit. The two sympatric species are given on either side of a hyphen (e.g. roem-drum = roemeriana and drummondii) * pat.zone: whether the paternal parent was from an allopatric location (allo) or a location that multiple species inhabit. The two sympatric species are given on either side of a hyphen * hybrid.cross: whether (y) or not (n) the cross was between parents of separate Phlox species * tray: which of the 38 seedling trays in the greenhouse the plant was grown in * days.to.flower: number of days from treatment to the opening of the first flower * mean.corolla.length: average corolla length in cm at the end of experiment (average of columns corolla1.length and corolla2.length) * mean.petal.length: average petal length in cm at the end of experiment (average of columns petal1.length and petal2.length) * mean.flower.area: average flower area in cm^2 at the end of experiment (average of columns flower1.area and flower1.area) * mean.end.leaf.length: average leaf length in cm at the end of experiment (average of columns end.length.leaf1 and end.length.leaf2) * CCI_mean_Atleaf: average leaf chlorophyll content index * germ_status: whether (1) or not (0) the plant germinated * flower_status: whether (1) or not (0) the plant flowered --- END OF README