Tables from: "A map of climate change-driven natural selection in Arabidopsis thaliana "

Through the lens of evolution, climate change is an agent of natural selection that forces populations to change and adapt, or face extinction. Current assessments of the risks associated with climate change, however, do not typically take into account that natural selection can dramatically impact the genetic makeup of populations. We made use of extensive genome information in Arabidopsis thaliana and measured how rainfall-manipulation affected the fitness of 517 natural lines grown in Spain and Germany. This allowed us to directly infer selection at the genetic level. Natural selection was particularly strong in the hot-dry Spanish location, killing 63% of lines and significantly changing the frequency of ~5% of all genome-wide variants. A significant proportion of this selection over variants could be predicted from the climate (mis)match between experimental sites and the geographic areas where variants are found (R2=29-52%). Field-validated predictions across the species range indicated that Mediterranean and Western Siberia populations — at the edges of the species' environmental limits — currently experience the strongest climate-driven selection, and Central Europeans the weakest. With rapidly increasing droughts and rising temperatures in Europe, we forecast a wave of directional selection moving North, putting many native A. thaliana populations at evolutionary risk.<br>

从进化生物学视角观之，气候变化是自然选择的作用因子，迫使种群发生演化与适应，否则将走向灭绝。然而，当前针对气候变化相关风险的评估，通常未将自然选择可显著影响种群遗传组成这一因素纳入考量范畴。我们依托拟南芥（Arabidopsis thaliana）的海量基因组信息，测定了降雨调控处理对在西班牙与德国种植的517份自然株系适合度的影响，借此得以直接推断遗传层面的自然选择作用。在炎热干旱的西班牙试验点，自然选择作用尤为强烈，淘汰了63%的株系，并显著改变了全基因组约5%变异位点的等位基因频率。此类变异位点所受选择作用的显著比例，可通过试验点与变异位点所在地理区域之间的气候错配程度进行预测（决定系数R²=29%~52%）。针对该物种分布范围的经田间试验验证的预测结果显示，处于物种环境耐受极限边缘的地中海种群与西西伯利亚种群，当前受气候驱动的自然选择作用最强，而中欧种群的选择作用最弱。随着欧洲地区干旱愈发频发、气温持续攀升，我们预测将出现一波向北扩散的定向选择浪潮，使诸多本土拟南芥种群面临演化风险。