METHODS: We created experimental populations of single individuals or a small number of plants to emulate isolated colonization events. These populations were composed of plants that differed in their ability to self-fertilize. We compared pollen limitation of the single individuals to that of small populations.
RESULTS: Experimental populations of plants that readily self-fertilize produced consistent seed numbers regardless of population size, whereas plants with lower ability to self-fertilize had density-dependent reproduction with greater seed production in small populations than in populations composed of a single individual.
CONCLUSIONS: We experimentally isolated the effect of mate limitation in colonization and found that it can select for increased self-fertilization. We show the benefit of self-fertilization in colonization, which helps to explain geographic patterns of self-fertilization and shows support for Baker\'s law, a long-held hypothesis in the field of mating-system evolution.
方法:我们创建了单个个体或少量植物的实验种群以模拟分离的定殖事件。这些种群由自体受精能力不同的植物组成。我们将单个个体的花粉限制与小种群的花粉限制进行了比较。
结果:无论种群大小,容易自体受精的植物的实验种群产生一致的种子数量,而自体受精能力较低的植物具有密度依赖性繁殖,与由单个个体组成的种群相比,小种群的种子产量更高。
结论:我们通过实验分离了配偶限制在定植中的作用,并发现它可以选择增加的自体受精。我们展示了自我受精在定植中的好处,这有助于解释自体受精的地理模式,并显示对贝克定律的支持,交配系统进化领域的一个长期假设。