Dissecting the contributions of plasticity and local adaptation to the phenology of a butterfly and its host plants

Phenology affects the abiotic and biotic conditions that an organism encounters and consequently its fitness. For populations of high latitude species, spring phenology often occurs earlier in warmer years and regions. Here we apply a novel approach to decompose spatiotemporal covariation between spring temperature and the phenology of two flowering plants, Cardamine pratensis and Alliara petiolata, and a Lepidopteran herbivore, Anthocharis cardamines, across the UK, into the contributions of plasticity and local adaptation. All three species overlap in the time-window over which mean temperatures best predict variation in phenology and we find little evidence that the position of time-windows varies latitudinally, as expected if they were initiated by day-length. The focal species show pronounced temperature-mediated phenological plasticity of similar magnitude. While we find no evidence for local adaptation in the flowering times of the plants, geographic variation in the phenology of...物候学（Phenology）会影响生物体所遭遇的非生物与生物条件（abiotic and biotic conditions），进而作用于其适合度（fitness）。对于高纬度物种种群而言，在更温暖的年份与区域，春季物候通常出现得更早。本研究采用一种全新方法，将英国全境范围内春季温度与两种开花植物——草甸碎米荠（Cardamine pratensis）和蒜芥（Alliara petiolata）——以及一种鳞翅目植食性昆虫（Lepidopteran herbivore）橙尖粉蝶（Anthocharis cardamines）的物候之间的时空协变关系（spatiotemporal covariation），分解为表型可塑性（plasticity）与本地适应（local adaptation）的贡献份额。三种研究物种在平均温度可最优预测物候变异的时间窗口（time-window）上存在重叠，且我们几乎未发现时间窗口的位置随纬度发生变化的证据——而若时间窗口由日照长度（day-length）启动，这一纬度梯度变化本应是预期中的结果。所聚焦的研究物种均表现出程度相近、由温度介导的显著物候可塑性。尽管我们未发现植物开花时间存在本地适应的证据，但物候的地理变异在……