The occurrence and extent of multiple paternity is an important component of variation in plant mating dynamics. However, links between pollinator activity and multiple paternity are generally lacking, especially for plant species that attract functionally diverse floral visitors. In this study, we separated the influence of two functionally distinct floral visitors (hawkmoths and solitary bees) and characterized their impacts on multiple paternity in a self-incompatible, annual forb, Oenothera harringtonii (Onagraceae). We also situated pollinator-mediated effects in a spatial context by linking variation in multiple paternity to variation in plant spatial isolation. We documented pronounced differences in the number of paternal sires as function of pollinator identity: on average, the primary pollinator (hawkmoths) facilitated mating with nearly twice as many pollen donors relative to the secondary pollinator (solitary bees). This effect was consistent for both isolated and non-isolated individuals, but spatial isolation imposed pronounced reductions on multiple paternity regardless of pollinator identity. Considering that pollinator abundance and pollen dispersal distance did not vary significantly with pollinator identity, we attribute variation in realized mating dynamics primarily to differences in pollinator morphology and behavior as opposed to pollinator abundance or mating incompatibility arising from underlying spatial genetic structure. Our findings demonstrate that functionally distinct pollinators can have strongly divergent effects on polyandry in plants and further suggest that both pollinator identity and spatial heterogeneity have important roles in plant mating dynamics.
Oenothera harringtonii microsatellite genotypes
Microsatellite genotypes for parental and offspring individuals included in this study. Each row represents a unique O. harringtonii individual whose identifier is given in the first column. In the "parents" sheet, the parentID column gives the unique identifier for each parental individual. In the "offspring" sheet, the offspringID column gives the unique identifier for each offspring individual, which consists of the maternal identifier followed by an indication of pollinator exclusion treatment (C = control, D = day-excluded, N = night-excluded) and an integer that distinguishes that individual from others in the same maternal sibship. In both sheets, subsequent columns contain allele sizes for each of seven diploid loci.
genotypes.xlsx
pollinator exclusion, spatial isolation and multiple paternity
Pollinator exclusion treatment, individual-level spatial isolation and correlated paternity estimates for the seed families included in this study. Each row represents a sample of seeds taken from a single fruit. For a given seed family, "plantID" gives the maternal line identifier, "treatment" gives the pollinator exclusion treatment (c = control, de = day-excluded, ne = night-excluded), "isolation20" gives the sum of Euclidean distances (m) between the maternal plant and its twenty nearest neighbors, and "correlatedPaternity" gives the MLTR estimate of correlated paternity.
multiplePaternity.csv
pollen dispersal distances
Pollen dispersal distances analyzed in this study. Each row represents a single seed for which a high-confidence paternity assignment was obtained. For each such seed, "treatment" gives the pollinator exclusion treatment (C = control, DE = day-excluded, NE = night-excluded) and "distance" gives the straight-line distance (m) between the maternal plant and the assigned paternal plant.
pollenDispersal.csv
morning pollinator visitation
Pollinator visitation data for morning observation periods during our study. Each row represents the visitation frequency of a certain type of pollinator during a given observation period. For each observation period, "abundance" gives the number of foraging bouts per observed flower, and "pollinator" gives the pollinator identity (bee or moth).
amPollinators.csv
evening pollinator visitation
Pollinator visitation data for evening observation periods during our study. Each row represents the visitation frequency of a certain type of pollinator during a given observation period. For each observation period, "abundance" gives the number of foraging bouts per observed flower, and "pollinator" gives the pollinator identity (bee or moth).
pmPollinators.csv
combined pollinator visitation
This file contains the morning and evening pollinator visitation data combined into one file, and was used in the pooled analysis of pollinator abundance.
overallPollinators.csv
pollinator foraging bouts
This file contains the number of different flowers visited during individual pollinator foraging bouts during our study. Each row represents a unique foraging bout. For each foraging bout, "time" gives the observation time (morning or evening), "visitor" gives the pollinator identity (hawkmoth or solitary bee) and "flowersVisited" gives the number of different flowers visited during that foraging bout.
pollinatorBouts.csv
dataframe for Figure 2
This file contains a simple table used to create Figure 2, which summarizes patterns of pollinator abundance during our study.
obs.csv
R script
R script to reproduce analyses and figures presented in this study.
Rhodes et al. 2017.R