DOI: 10.5061/dryad.3n5tb2rrp
title: Soil and climate contribute to maintenance of a flower color polymorphism

description: Premise of the Study: Floral pigments such as anthocyanins are well-known
 to influence pollinator attraction, yet they also confer tolerance to
 abiotic stressors such as harsh soils, extreme temperatures, low
 precipitation, or UV radiation. In such cases, environmental variation in
 abiotic stressors over space or time could lead to the maintenance of
 flower color variation within species. Under this scenario, flower color
 in natural populations should covary with environmental stressors.
 Methods: Using a comparative approach, we test whether abiotic variables
 predict flower color in Leptosiphon parviflorus, a species with pink and
 white flower color morphs. We conduct in-depth field studies to assess
 morph frequency, soil chemistry, and climate. We then employ community
 scientist-powered iNaturalist observations to examine patterns across even
 larger spatial scales. Key Results: Across 21 field sites we find that L.
 parviflorus has a higher frequency of pink morphs in sites with serpentine
 soil, higher average annual temperatures, and higher average climatic
 water deficit (a proxy for drought stress). iNaturalist observations
 support this finding—the probability of flowers being pink is greater in
 locations with serpentine-derived soil, especially when the local average
 UV radiation and climatic water deficit are higher. Conclusions: Spatial
 variation in abiotic stressors may contribute to the maintenance of flower
 color variation across the geographic range of L. parviflorus and other
 clade members.  Future studies will examine mechanisms by which
 flower color affects stress tolerance and will assess whether fitness
 tradeoffs in contrasting habitats are associated with flower color.
description: # Soil and climate contribute to maintenance of a flower color
 polymorphism
 [https://doi.org/10.5061/dryad.3n5tb2rrp](https://doi.org/10.5061/dryad.3n5tb2rrp) ## Description of the data and file structure The associated files include the following datasets of Leptosiphon parviflorus: 1. field data from 21 sites with 526 individuals sampled (526 rows in the data; Data_Lparv_field.csv) 2. summarized field data for the 21 sites with site means (21 rows in the data; Data_Lparv_field_summary.csv) 3. photo point data from 1071 iNaturalist observations (1071 rows in the data; Data_Lparv_photopoints.csv) The associated files also include R scripts of statistical analyses for each of the above datasets: 1. analysis of summarized field data (1_analysis_field.R) 2. analysis of photo point data (2_analysis_photopoint.R) 3. analysis of field data for Appendix 2 (3_analysis Appendix S2.R) ### Files and variables #### File: Data\_Lparv\_field\_summary.csv **Description:**  Summarized field survey data for 21 sites where each row represents one site. Missing values are indicated with "NA" ##### Variables * Patch_Name: Transect name (note that this represents 'site' in the main text) * Site: Region name * Site_Code: Unique 2 letter code for the site * Date: month/day/year format * Observers: Last names of observers in the field * latitude: decimal degrees * longitude: decimal degrees * Transect_Length_M: length of transect in meters * Sample_interval_M: Interval along the transect where plants were sampled in meters (note that this doesn't mean that individuals were spaced exactly on this interval-- we identified the nearest individual to the interval which may have been offset on either side of the transect) * Petal_Color_mean: Proportion of individuals sampled that were pink morphs * Soil_Depth_Ave_mean: Average field soil depth in centimeters * Prop_bare_mean: Average proportion of bare ground around each focal individual achieved by centering a gridded 25 cm × 25 cm quadrat over the focal plant and using a point-intercept method to score points (N = 16) for bare ground. * Sgreen_mean: Average Sgreen (quantified from corolla lobe photos using RGB values, Sgreen = red/(mean red + mean green + mean blue).  * ppt: Average annual precipitation in millimeters extracted from the PRISM dataset using 30-year averages from 1991–2020 * tmean: Average annual temperature in degrees celsius extracted from the PRISM dataset using 30-year averages from 1991–2020 * uvb: UV-B radiation values were extracted from gIUV dataset and represent the sum of monthly mean UV-B during the highest quarter * cwd: Average climatic water deficit (CWD) values extracted from the TerraClimate gridded data set using 30-year averages from 1991–2020 * substrate: serpentine or non-serpentine based on GIS shapefiles of ultramafic substrates in California * NH4_N: nitrogen (N) as ammonium (NH4+) mg/kg * P: phosphorus lb/A * K: potassium lb/A * Mg: magnesium lb/A * Ca: calcium lb/A * Ca_Mg: calcium to magnesium ratio * Co_dtpa: cobalt mg/kg * Cr_dtpa: chromium mg/kg * Ni_dtpa: nickel mg/kg * perc_sand: percent sand content * perc_silt: percent silt content * perc_clay: percent clay content #### File: Data\_Lparv\_field.csv **Description:** field survey data for 21 sites where each row represents one focal individual (526 individuals). Missing values are indicated with "NA" ##### Variables * Site: Region name * Patch_Name: Transect name (note that this represents 'site' in the main text) * ID: Unique plant ID within the site * Date: Month/Day/Year * Observers: Last names of observers in the field * latitude: decimal degrees * longitude: decimal degrees * Transect_Length_M: length of transect in meters * Aspect_deg: Aspect in degrees that patch is facing * Slope_deg: Slope in degrees * Sample_interval_M: Interval along the transect where plants were sampled in meters (note that this doesn't mean that individuals were spaced exactly on this interval-- we identified the nearest individual to the interval which may have been offset on either side of the transect) * Petal_Color: corolla lobe color scored in field as 0 white, 1 light pink, 2 dark pink, 3 yellow * Throat_Color: corolla throat color scored in field as 0 yellow, 1 dark * Nectar_Guides: corolla nectar guides scored in field as 0 none, 1 yellow, 2 red * Num_Bud: number of buds on plant at time of observation * Num_Flower: number of flowers on plant at time of observation * Num_Fruit: number of fruits on plant at time of observation * BareGround: Number of points with bare ground around each focal individual. This was achieved by centering a gridded 25 cm × 25 cm quadrat over the focal plant and using a point-intercept method to score points (N = 16) for bare ground. * Litter_Thatch: Number of points with litter or thatch around each focal individual. This was achieved by centering a gridded 25 cm × 25 cm quadrat over the focal plant and using a point-intercept method to score points (N = 16) for litter or thatch. * Grass: Number of points with grass around each focal individual. This was achieved by centering a gridded 25 cm × 25 cm quadrat over the focal plant and using a point-intercept method to score points (N = 16) for grass. * OtherForb: Number of points with forbs other than L parviflorus around each focal individual. This was achieved by centering a gridded 25 cm × 25 cm quadrat over the focal plant and using a point-intercept method to score points (N = 16) for forb. * Conspecifics: Number of points with conspecifics around each focal individual. This was achieved by centering a gridded 25 cm × 25 cm quadrat over the focal plant and using a point-intercept method to score points (N = 16) for conspecifics. * Woody: Number of points with woody plants around each focal individual. This was achieved by centering a gridded 25 cm × 25 cm quadrat over the focal plant and using a point-intercept method to score points (N = 16) for litter or thatch. * Soil_Collected_2cups: yes indicates that 2 cups of sieved soil were collected for future analysis * Num_Holes: Number of holes dug in order to equal 2 cups of sieved soil * Soil_Depth_Ave: Average maximum depth of holes dug in centimeters. Note that the max recorded was 15 cm. * Tissue_Collected: Yes indicates that tissue was collected from the focal plant * Picture_Number.x: The x coordinates associated with that flower in the tray in which they were photographed * Picture_Number.y: The y coordinates associated with that flower in the tray in which they were photographed * R: Red values quantified from corolla lobe photos using image J * G: Green values quantified from corolla lobe photos using image J * B: Blue values quantified from corolla lobe photos using image J * Notes: Additional information * Tray.Color: Color of tray used for photographing corolla lobes #### File: Data\_Lparv\_photopoints.csv **Description:** iNaturalist photo point data where each row represents one photo point (1071 photo points). Missing values are indicated with "NA" ##### Variables * id: unique identifier from iNaturalist observation * latitude: decimal degrees * longitude: decimal degrees * substrate: serpentine or non-serpentine based on GIS shapefiles of ultramafic substrates in California * tmean: Average annual temperature in degrees celsius extracted from the PRISM dataset using 30-year averages from 1991–2020 * ppt: Average annual precipitation in millimeters extracted from the PRISM dataset using 30-year averages from 1991–2020 * uvb: UV-B radiation values were extracted from gIUV dataset and represent the sum of monthly mean UV-B during the highest quarter * cwd: Average climatic water deficit (CWD) values extracted from the TerraClimate gridded data set using 30-year averages from 1991–2020 * flower_color_raw: corolla lobe color scored as either white, pink or yellow * flower_color: corolla lobe color scored as either pink or nonpink (includes white and yellow morphs) * binary_col: corolla lobe color scored as 1 (pink) or 0 (nonpink) * throat: corolla throat color scored as either light or dark * binary_throat: corolla throat color scored as 1 (dark) or 0 (light) * notes: additional notes * observed_on: date iNaturalist observation was taken * quality_grade: grade of iNaturalist observation (all are research grade) * image_url: internet address of iNaturalist photo point scored for flower color #### File: Ultramafic alluvium CFP.zip **Description:** GIS shapefile of ultramafic alluvium within the California Floristic Province. #### File: Ultramafic landslides CFP.zip **Description:** GIS shapefile of ultramafic landslide within the California Floristic Province. #### File: Ultramafic masses CFP.zip **Description:** GIS shapefile of ultramafic masses within the California Floristic Province. ## Code/software R scripts of statistical analyses: 1. analysis of summarized field data (1_analysis_field.R) 2. analysis of photo point data (2_analysis_photopoint.R) 3. analysis of field data for Appendix 2 (3_analysis Appendix S2.R) Note that all scripts were run using R version 4.4.1 (2024-06-14)