Data from: Rapid evolution of dispersal ability makes biological invasions faster and more variable

Genetic variation in dispersal ability may result in the spatial sorting of alleles during range expansion. Recent theory suggests that spatial sorting can favour the rapid evolution of life history traits at expanding fronts, and therefore modify the ecological dynamics of range expansion. Here we test this prediction by disrupting spatial sorting in replicated invasions of the bean beetle Callosobruchus maculatus across homogeneous experimental landscapes. We show that spatial sorting promotes rapid evolution of dispersal distance, which increases the speed and variability of replicated invasions: after 10 generations of range expansion, invasions subject to spatial sorting spread 8.9% farther and exhibit 41-fold more variable spread dynamics relative to invasions in which spatial sorting is suppressed. Correspondingly, descendants from spatially evolving invasions exhibit greater mean and variance in dispersal distance. Our results reveal an important role for rapid evolution during invasion, even in the absence of environmental filters, and argue for evolutionarily informed forecasts of invasive spread by exotic species or climate change migration by native species.

扩散能力的遗传变异可导致物种在范围扩张过程中发生等位基因的空间分选（spatial sorting of alleles）。近期理论研究指出，空间分选可促使扩张前沿的生活史特征（life history traits）快速演化，进而改变范围扩张的生态动力学过程。本研究通过在均质实验景观中开展重复的绿豆象（Callosobruchus maculatus）入侵实验，干扰其等位基因空间分选过程，以此检验该理论预测。结果表明，空间分选可促进扩散距离（dispersal distance）的快速演化，进而提升重复入侵实验的扩张速度与变异程度：在经历10代范围扩张后，发生空间分选的入侵种群的扩散距离较空间分选被抑制的种群远8.9%，且其扩张动态的变异程度是后者的41倍。相应地，经历空间分选演化的入侵种群后代的扩散距离均值与方差均更高。本研究结果揭示了入侵过程中快速演化的重要作用，即便在不存在环境过滤因子（environmental filters）的情况下；同时呼吁在外来物种入侵扩散以及本土物种气候变化介导的迁移预测中纳入演化维度的考量。