Department of Ecology, Environment and Plant Science, Stockholm University, SE-106 91, Stockholm, Sweden.
Department of Zoology, Stockholm University, SE-106 91, Stockholm, Sweden.
Ecology. 2017 Mar;98(3):703-711. doi: 10.1002/ecy.1676. Epub 2017 Feb 1.
Temporal variation in natural selection has profound effects on the evolutionary trajectories of populations. One potential source of variation in selection is that differences in thermal reaction norms and temperature influence the relative phenology of interacting species. We manipulated the phenology of the butterfly herbivore Anthocharis cardamines relative to genetically identical populations of its host plant, Cardamine pratensis, and examined the effects on butterfly preferences and selection acting on the host plant. We found that butterflies preferred plants at an intermediate flowering stage, regardless of the timing of butterfly flight relative to flowering onset of the population. Consequently, the probability that plant genotypes differing in timing of flowering should experience a butterfly attack depended strongly on relative phenology. These results suggest that differences in spring temperature influence the direction of herbivore-mediated selection on flowering phenology, and that climatic conditions can influence natural selection also when phenotypic preferences remain constant.
自然选择的时间变化对种群的进化轨迹有深远的影响。选择的一个潜在变异源是，热反应规范和温度的差异影响相互作用的物种的相对物候期。我们操纵蝴蝶食草动物 Anthocharis cardamines 的物候期相对于其宿主植物 Cardamine pratensis 的遗传上相同的种群，并研究了对蝴蝶偏好和作用于宿主植物的选择的影响。我们发现，蝴蝶无论相对于种群开花起始的蝴蝶飞行时间如何，都偏好处于中间开花阶段的植物。因此，开花时间不同的植物基因型应该经历蝴蝶攻击的可能性强烈依赖于相对物候期。这些结果表明，春季温度的差异会影响食草动物介导的对开花物候的选择方向，并且即使表型偏好保持不变，气候条件也会影响自然选择。
