Data from: Insect herbivores drive real-time ecological and evolutionary change in plant populations

Insect herbivores are hypothesized to be major factors affecting the ecology and evolution of plants. We tested this prediction by suppressing insects in replicated field populations of a native plant, Oenothera biennis, which reduced seed predation, altered interspecific competitive dynamics, and resulted in rapid evolutionary divergence. Comparative genotyping and phenotyping of nearly 12,000 O. biennis individuals revealed that in plots protected from insects, resistance to herbivores declined through time due to changes in flowering time and lower defensive ellagitannins in fruits, whereas plant competitive ability increased. This independent real-time evolution of plant resistance and competitive ability in the field resulted from the relaxation of direct selective effects of insects on plant defense and through indirect effects due to reduced herbivory on plant competitors.

植食性昆虫（Insect herbivores）被假定为影响植物生态学与进化进程的主要因素。我们通过在本地植物月见草（Oenothera biennis）的重复野外种群中开展昆虫抑制实验，对这一假说进行了验证：该处理降低了种子捕食压力、改变了种间竞争动态，并促使植物产生了快速的进化分化。对近12000株月见草个体开展的比较基因组分型与表型分析结果显示，在免受昆虫侵扰的样地中，植物的抗植食性随时间推移逐渐下降，这一变化源于开花时间的改变以及果实中防御性鞣花单宁（ellagitannins）含量的降低；与此同时，植物的竞争能力则得到了提升。野外环境下植物抗植食性与竞争能力的这种独立实时进化，源于两方面因素：一是昆虫对植物防御的直接选择压力得以松弛，二是植物竞争者的植食性损害减少所带来的间接效应。