Data from: Evolution of resistance to a multiple-herbavore community: genetic correlations, diffuse coevolution, and constraints on the plant's response to selection

Although plants are generally attacked by a community of several species of herbivores, relatively little is known about the strength of natural selection for resistance in multiple-herbivore communities—particularly how the strength of selection differs among herbivores that feed on different plant organs or how strongly genetic correlations in resistance affect the evolutionary responses of the plant. Here, we report on a field study measuring natural selection for resistance in a diverse community of herbivores of Solanum carolinense. Using linear phenotypic-selection analyses, we found that directional selection acted to increase resistance to seven species. Selection was strongest to increase resistance to fruit feeders, followed by flower feeders, then leaf feeders. Selection favored a decrease in resistance to a stem borer. Bootstrapping analyses showed that the plant population contained significant genetic variation for each of 14 measured resistance traits and significant covariances in one-third of the pairwise combinations of resistance traits. These genetic covariances reduced the plant's overall predicted evolutionary response for resistance against the herbivore community by about 60%. Diffuse (co)evolution was widespread in this community, and the diffuse interactions had an overwhelmingly constraining (rather than facilitative) effect on the plant's evolution of resistance.

尽管植物通常会受到多种植食性动物类群的侵袭，但针对多植食者群落中抗虫性相关自然选择强度的研究仍相对匮乏——尤其是取食不同植物器官的植食者间选择强度存在何种差异，以及抗虫性的遗传相关程度会在多大程度上影响植物的进化响应。本研究针对卡罗莱纳茄（Solanum carolinense）的多样植食者群落开展野外试验，测定其抗虫性相关的自然选择作用。通过线性表型选择分析，我们发现定向选择对7种植食者的抗虫性均起到提升作用。其中，针对果实取食者的抗虫性选择强度最高，其次为花部取食者，再次为叶部取食者；而针对茎部蛀虫的抗虫性则受到选择的负向作用（即选择倾向于降低对该类植食者的抗虫性）。Bootstrap分析结果显示，该植物种群在14个测定的抗虫性状上均存在显著的遗传变异，且在三分之一的抗虫性状两两组合中存在显著的遗传协方差。这些遗传协方差使得该植物种群针对整个植食者群落的抗虫性整体预测进化响应降低了约60%。弥散（共）进化在该群落中广泛存在，且弥散性相互作用对植物抗虫性的进化整体起到了显著的约束作用（而非促进作用）。