Data from: Mating system plasticity promotes persistence and adaptation of colonizing populations of hermaphroditic angiosperms

Persistence and adaptation in novel environments are limited by small population size, strong selection, and maladaptive gene flow. Mating system plasticity is common in angiosperms and may provide both demographic and genetic benefits that promote niche evolution, including reproductive assurance and isolation from maladaptive gene flow. Yet increased self-fertilization may also cause inbreeding depression, accumulation of deleterious mutations, and reduced adaptive potential. Here we use individual-based simulations to examine the consequences of mating system plasticity for persistence and adaptation in a novel environment that imposes selection on a quantitative trait. We examine the joint evolution of local adaptation, inbreeding depression, and genetic load. We find that a plastic shift to a mixed mating system generally promotes niche evolution by decreasing the risk of extinction, providing isolation from maladaptive gene flow, and temporarily increasing genetic variance in the trait under selection, whereas obligate self-fertilization reduces adaptive potential. These effects are most pronounced under conditions of mate limitation, strong selection, or maladaptive gene flow. Our results highlight the diverse demographic and genetic consequences of self-fertilization and support the potential role for plastic shifts in mating system to promote niche evolution in flowering plants.新环境中的种群存续与适应性演化受限于种群规模偏小、选择强度过高以及有害基因流（maladaptive gene flow）。被子植物（angiosperms）中普遍存在交配系统可塑性（mating system plasticity），其能够带来可促进生态位演化（niche evolution）的种群统计学与遗传学益处，包括繁殖保障以及免受有害基因流干扰的种群隔离效应。然而，增强的自交作用也可能引发近交衰退（inbreeding depression）、有害突变积累以及适应性潜力下降。本研究采用基于个体的模拟（individual-based simulations）方法，探究在对某一数量性状（quantitative trait）施加选择压力的新环境中，交配系统可塑性对种群存续与适应性演化的影响。我们同时考察了局部适应性、近交衰退与遗传负荷（genetic load）的协同演化。研究结果表明，可塑性转变为混合交配系统（mixed mating system）通常可通过降低灭绝风险、规避有害基因流的隔离效应，以及暂时提升受选择性状的遗传方差，来促进生态位演化；而专性自交（obligate self-fertilization）则会降低适应性潜力。上述效应在配偶限制、选择强度过高或存在有害基因流的条件下最为显著。本研究结果凸显了自交作用所带来的多样化种群统计学与遗传学后果，并支持了交配系统的可塑性转变可促进被子植物生态位演化的潜在可能性。