Department of Ecology, Environment and Plant Sciences, Stockholm University, 106 91 Stockholm, Sweden.
Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden.
Proc Biol Sci. 2023 Sep 13;290(2006):20230670. doi: 10.1098/rspb.2023.0670. Epub 2023 Sep 6.
In seasonal environments, a high responsiveness of development to increasing temperatures in spring can infer benefits in terms of a longer growing season, but also costs in terms of an increased risk of facing unfavourable weather conditions. Still, we know little about how climatic conditions influence the optimal plastic response. Using 22 years of field observations for the perennial forest herb , we assessed phenotypic selection on among-individual variation in reaction norms of flowering time to spring temperature, and examined if among-year variation in selection on plasticity was associated with spring temperature conditions. We found significant among-individual variation in mean flowering time and flowering time plasticity, and that plants that flowered earlier also had a more plastic flowering time. Selection favoured individuals with an earlier mean flowering time and a lower thermal plasticity of flowering time. Less plastic individuals were more strongly favoured in colder springs, indicating that spring temperature influenced optimal flowering time plasticity. Our results show how selection on plasticity can be linked to climatic conditions, and illustrate how we can understand and predict evolutionary responses of organisms to changing environmental conditions.
在季节性环境中，春季温度升高对发育的高度响应可以带来更长的生长季节的好处，但也会增加遭遇不利天气条件的风险。尽管如此，我们对气候条件如何影响最佳可塑性反应知之甚少。本研究使用 22 年的多年生森林草本植物的野外观测数据，评估了开花时间对春季温度反应规范的个体间变异性的表型选择，并检验了可塑性选择的年际变化是否与春季温度条件有关。我们发现，开花时间的平均值和开花时间可塑性存在显著的个体间变异性，而且开花较早的植物也具有更具可塑性的开花时间。选择有利于具有较早平均开花时间和较低开花时间热可塑性的个体。在较冷的春季，可塑性较低的个体更受青睐，这表明春季温度会影响最佳开花时间的可塑性。我们的研究结果表明，可塑性选择可以与气候条件联系起来，并说明了我们如何理解和预测生物对不断变化的环境条件的进化反应。
