DOI: 10.5061/dryad.hx3ffbgks
title: Experimental and genetic analysis of selfing reveals no reinforcement in Phlox cuspidata

description: Reinforcement is the process through which prezygotic reproductive
 barriers evolve in sympatry due to selection against hybridization between
 co-occurring, closely related species. The role of self-fertilization in
 reinforcement and reproductive isolation is uncertain in part because its
 efficiency as a barrier against heterospecific mating can depend on the
 timing of autonomous selfing. To investigate whether increased autonomous
 selfing has evolved as a mechanism for reinforcement, we compared Phlox
 cuspidata populations across their native Texas range using both estimates
 of genetic diversity and experimental manipulation with morphological
 measurements. Specifically, we investigated patterns of variation in
 floral traits and timing of selfing between individuals from allopatric
 populations of P. cuspidata and from populations sympatric with the
 closely related species, P. drummondii. We infer intermediate rates of
 selfing across field-collected individuals with no significant difference
 between allopatric and sympatric populations. Among greenhouse grown
 plants, we find no differences in timing of selfing or other floral traits
 including anther dehiscence timing, anther-stigma distances, autonomous
 selfing rate and self-seed count between allopatric and sympatric
 populations. However, our statistical analyses indicate that P.
 cuspidata individuals sympatric with P drummondii seem to have generally
 larger flowers compared to allopatric individuals. Despite strong evidence
 of costly hybridization with P. drummondii, we find no evidence of trait
 divergence due to reinforcement in P. cuspidata. Although we document
 nearly complete autonomous self-seed set in the greenhouse, estimates of
 selfing rates from genetic data imply realized selfing is much lower in
 nature suggesting an opportunity for reinforcing selection to act on this
 trait. 
description: This folder contains the data and code for the article titled:
 Experimental and genetic analyses of selfing reveals no reinforcement in
 Phlox cuspidata Comments and requests should be addressed to Bushra
 Shahid: bushra.shahid@usys.ethz.ch. All material is free of use, but
 please cite the paper whenever appropriate. The folder named Data contains
 six .csv files and an R file for the final version of the manuscript. \---
 Summary The manuscript aimed to investigate whether increased autonomous
 selfing has evolved as a mechanism for reinforcement, we compared Phlox
 cuspidata populations across their native Texas range using both estimates
 of genetic diversity and experimental manipulation with morphological
 measurements. Specifically, we investigated patterns of variation in
 floral traits and timing of selfing between individuals from allopatric
 populations of P. cuspidata and from populations sympatric with the
 closely related species, P. drummondii. We infer intermediate rates of
 selfing across field-collected individuals with no significant difference
 between allopatric and sympatric populations. Among greenhouse grown
 plants, we find no differences in timing of selfing or other floral traits
 including anther dehiscence timing, anther-stigma distances, autonomous
 selfing rate and self-seed count between allopatric and sympatric
 populations. However, our statistical analyses indicate that P. cuspidata
 individuals sympatric with P drummondii tend to have significantly bigger
 flowers compared to allopatric individuals. Description of the data and
 file structure The individual CSV files contain quantitative trait values
 for 6 traits measured using Phlox cuspidata individuals from sympatric and
 allopatric populations (categorical). The "Pop" refers to the
 population (categorical), "Pot_ID" is the pot number for each
 potted plant in the experiment (categorical). the "ID"
 (categorical) is a unique number given to each indiviudal consisting of
 their population, mom ID and offspring number ^. The files are as follows:
 1\. Flower_size: Contains flower length and diameter values in cm
 (continuous) for a minimum of 3 flowers on each individual sampled. The
 columns include the * Pot_Id (categorical) * a unique ID (categorical) *
 Mom ID (categorical) * Population (categorical) * Length 1-3 in cm
 (continuous) * Diameter 1-3 in cm (continuous) 2\. Internode: Contains the
 internode length in cm (continuous) as measured between the second and
 third internode on each sample. The columns include the * Pot_Id
 (categorical) * a unique ID (categorical) * Mom ID (categorical) *
 Population (categorical) * Internode length in cm (continuous). 3\.
 A-S_distance: Contains the lengths in cm (continuous) of each of 5 anthers
 (A1-5) and the pistil (P) on Stage 0 (bud the day before it opens) and
 Stage 1 (day 1 of an open flower) for each sample. There are 2 replicates
 per sample for reproducibility. These values were used to obtain the
 minimum distance between the anther and stigma in cm. The columns include
 * Pot_Id (categorical) * a unique ID (categorical) * Mom ID (categorical)
 * Population (categorical) * Replicate number (categorical) * anther
 length of Stage0 A1-5 and Stage1A1-5 and pistil lengths in Stage 0 and
 Stage 1 (all continuous). 4\. Fruit_set: Contains the number of fruit set
 (discrete) on the respective stages (Day 0 to 4) for each sample. The
 columns include * Pot_Id (categorical) * a unique ID (categorical) *
 Population (categorical) * fruit set in the 5 days (discrete). 5\. Selfing
 rate: Contains the number of fruits (discrete) and seed set (discrete)
 after bagging known number of fruits (discrete). Also contains a column
 called selfing rate (continuous) which was estimated using the proportion
 of flowers that set fruit. The columns include * Pot_Id (categorical) * a
 unique ID (categorical) * Population (categorical) * the selfing rate
 (continuous) * number of fruits set (discrete) * number of seeds produced
 by the said number of fruits (discrete). 6\. Fis: Contains the inbreeding
 coefficient and genetic selfing rate values for the populations. The
 columns include * population (categorical) * selfing rate (s) (continuous)
 * Fis inbreeding coefficient (continuous) * minor allele frequency (MAF) *
 zone (categorical) * lat and long values (continuous) * number of
 individuals (discrete). Code/Software An R script is provided which was
 used to create models and plots for each of the trait trait values listed
 above along with genetic selfing rates. Packages used included tidyverse,
 lmerTest, ggeffects and dplyr.