Data from: Rapid evolution mitigates the ecological consequences of an invasive species (Bythotrephes longimanus) in lakes in Wisconsin

Invasive species have extensive negative consequences for biodiversity and ecosystem health. Novel species also drive contemporary evolution in many native populations, which could mitigate or amplify their impacts on ecosystems. The predatory zooplankton Bythotrephes longimanus invaded lakes in Wisconsin, USA, in 2009. This invasion caused precipitous declines in zooplankton prey (Daphnia pulicaria), with cascading impacts on ecosystem services (water clarity). Here, we tested the link between Bythotrephes invasion, evolution in Daphnia and post-invasion ecological dynamics using 15 years of long-term data in conjunction with comparative experiments. Invasion by Bythotrephes is associated with rapid increases in the body size of Daphnia. Laboratory experiments revealed that such shifts have a genetic component; third-generation laboratory-reared Daphnia from ‘invaded’ lakes are significantly larger and exhibit greater reproductive effort than individuals from ‘uninvaded’ lakes. This trajectory of evolution should accelerate Daphnia population growth and enhance population persistence. We tested this prediction by comparing analyses of long-term data with laboratory-based simulations, and show that rapid evolution in Daphnia is associated with increased population growth in invaded lakes.外来入侵物种会对生物多样性与生态系统健康造成广泛的负面影响。外来新物种还会驱动诸多本土种群发生当代进化，这种进化或可缓解、亦或加剧其对生态系统的影响。掠食性浮游动物长柱尾突溞（Bythotrephes longimanus）于2009年入侵美国威斯康星州的诸多湖泊。此次入侵导致作为其猎物的浮游动物蚤状溞（Daphnia pulicaria）种群出现骤降，并对生态系统服务（水体透明度）产生了级联效应。本研究依托15年长期监测数据结合对照实验，探究了长柱尾突溞入侵、溞属种群进化与入侵后生态动态之间的关联。长柱尾突溞的入侵与溞属种群的体型快速增大显著相关。室内实验表明，这类体型变化具有遗传基础：来自"已入侵湖泊"的实验室饲养至第三代的溞个体，其体型显著大于来自"未入侵湖泊"的个体，且繁殖投入更高。这种进化轨迹应能加速溞种群的增长，并提升其种群存续能力。本研究通过对比长期数据分析与室内模拟实验验证了这一预测，并证实溞属种群的快速进化与入侵湖泊中溞种群增长加快存在显著关联。