Marshall Matthew M, Batten Leslie C, Remington David L, Lacey Elizabeth P
Department of Biology University of North Carolina at Greensboro Greensboro North Carolina.
Ecol Evol. 2019 Feb 14;9(5):2945-2963. doi: 10.1002/ece3.4977. eCollection 2019 Mar.
A long-standing debate in evolutionary biology concerns the relative importance of different evolutionary forces in explaining phenotypic diversification at large geographic scales. For example, natural selection is typically assumed to underlie divergence along environmental gradients. However, neutral evolutionary processes can produce similar patterns. We collected molecular genetic data from 14 European populations of to test the contributions of natural selection versus neutral evolution to population divergence in temperature-sensitive phenotypic plasticity of floral reflectance. In . reflectance plasticity is positively correlated with latitude/altitude. We used population pairwise comparisons between neutral genetic differentiation ( and Jost's ) and phenotypic differentiation ( ) to assess the contributions of geographic distance and environmental parameters of the reproductive season in driving population divergence. Data are consistent with selection having shaped large-scale geographic patterns in thermal plasticity. The aggregate pattern of versus was consistent with divergent selection. explained thermal plasticity differences only when geographic distance was not included in the model. Differences in the extent of cool reproductive season temperatures, and not overall temperature variation, explained plasticity differences independent of distance. Results are consistent with the hypothesis that thermal plasticity is adaptive where growing seasons are shorter and cooler, that is, at high latitude/altitude.
进化生物学中一个长期存在的争论涉及不同进化力量在解释大地理尺度上的表型多样化时的相对重要性。例如，通常认为自然选择是沿环境梯度分化的基础。然而，中性进化过程也能产生类似的模式。我们从欧洲14个种群中收集了分子遗传数据，以测试自然选择与中性进化对花卉反射率温度敏感表型可塑性中种群分化的贡献。在……中，反射率可塑性与纬度/海拔呈正相关。我们利用中性遗传分化（……和乔斯特氏……）与表型分化（……）之间的种群成对比较，来评估地理距离和繁殖季节环境参数在推动种群分化中的作用。数据表明选择塑造了热可塑性的大规模地理模式。……与……的总体模式与趋异选择一致。只有在模型中不包括地理距离时，……才能解释热可塑性差异。凉爽繁殖季节温度的差异，而非总体温度变化，解释了与距离无关的可塑性差异。结果与以下假设一致：在生长季节较短且较凉爽的地方，即高纬度/高海拔地区，热可塑性具有适应性。
