DOI: 10.5061/dryad.d2547d819
title: Global patterns of population genetic differentiation in seed plants

description: Evaluating the factors that drive patterns of population differentiation
 in plants is critical for understanding several biological processes such
 as local adaptation and incipient speciation. Previous studies have given
 conflicting results regarding the significance of pollination mode, seed
 dispersal mode, mating system, growth form, and latitudinal region in
 shaping patterns of genetic structure, as estimated by FST values, and no
 study to date has tested their relative importance together across a broad
 scale. Here we assembled a 337-species dataset for seed plants from
 publications with data on FST from nuclear markers and species traits,
 including variables pertaining to the sampling scheme of each study. We
 used species traits, while accounting for sampling variables, to perform
 phylogenetic multiple regressions. Results demonstrated that FST values
 were higher for tropical, mixed-mating, non-woody species pollinated by
 small insects, indicating greater population differentiation, and lower
 for temperate, outcrossing trees pollinated by wind. Among the factors we
 tested, latitudinal region explained the largest portion of variance,
 followed by pollination mode, mating system and growth form, while seed
 dispersal mode did not significantly relate to FST. Our analyses provide
 the most robust and comprehensive evaluation to date of the main
 ecological factors predicted to drive population differentiation in seed
 plants, with important implications for understanding the basis of their
 genetic divergence. Our study supports previous findings showing greater
 population differentiation in tropical regions and is the first that we
 are aware of to robustly demonstrate greater population differentiation in
 species pollinated by small insects.
description: The main dataset was collected from a systematic literature
 review in google scholar. From the manuscript: "We
 constructed an F<sub>ST</sub> dataset through a systematic
 search in google scholar (key words: “plant” AND —the following words,
 each in a separate search— “genetic structure”, “population
 differentiation”, “population genetics”, “genetic diversity”, “population
 gene flow”) for articles published up until June 2018. The search yielded
 thousands of studies, which we reduced to 356 peer-reviewed publications
 on seed plants that determined population genetic structure
 (F<sub>ST</sub>) based on nuclear markers. When multiple
 studies reported F<sub>ST</sub> values for the same species,
 we recorded the F<sub>ST</sub> from the study with the largest
 geographic range, as this may better represent the genetic diversity found
 in the species (Cavers et al., 2005). By this criterion, we compiled a
 dataset that included 337 unique species. We extracted information for the
 predictor variables directly from the publications, and infrequently
 complemented this, where necessary, with information from peer-reviewed
 literature on the studied species (see Appendix S1 and Table S1 in
 Supporting Information). Predictor variables were included in multiple
 regressions to explain variation in F<sub>ST</sub> values (see
 section F<sub>ST</sub> models). We also included three factors
 that pertained to the sampling scheme of each study and that can
 potentially affect F<sub>ST </sub>(Nybom, 2004; Nybom
 & Bartish, 2000): genetic marker used, maximum distance between
 populations, mean sample size per population. We used them to construct a
 null model to be compared against models with our factors of interest.
 Factors of interest consisted of five categorical variables with 2–4
 levels: mating system (outcrossing, mixed-mating), growth form (non-woody,
 shrub, tree), pollination mode (large insects, small insects, vertebrates,
 wind), seed dispersal mode (animal, gravity, wind), and latitudinal region
 (tropics, sub-tropics, temperate)."
description: Fst_data.csv: dataset analyzed in this study
 Fst_spp.csv: species list of this study (used to produce
 phylogeny) Fst_script.R: R script to reproduce all
 results (preliminary and final) of the manuscript 
 FST.Phylo.tre: phylogeny of studied species
 All other .csv files (20 in total) correspond to 10 reduced
 datasets and their corresponding species list