Data from: The effect of selection history on extinction risk during severe environmental change

Environments rarely remain the same over time, and populations are therefore frequently at risk of going extinct when changes are significant enough to reduce fitness. While many studies have investigated what attributes of the new environments and of the populations experiencing these changes will affect their probability of going extinct, limited work has been directed toward determining the role of population history on the probability of going extinct during severe environmental change. Here we compare the extinction risk of populations with a history of selection in a benign environment, to populations with a history of selection in one or two stressful environments. We exposed spores and lines of the green alga Chlamydomonas reinhardtii from these three different histories to a range of severe environmental changes. We found that the extinction risk was higher for populations with a history of selection in stressful environments compared to populations with a history of selection in a benign environment. This effect was not due to differences in initial population sizes. Finally, the rates of extinction were highly repeatable within histories, indicating strong historical contingency of extinction risk. Hence, information on the selection history of a population can be used to predict their probability of going extinct during environmental change.环境随时间推移极少保持恒定，因此当环境变化剧烈到足以降低种群适应度时，种群常面临灭绝风险。尽管已有诸多研究探讨了新环境属性与经历此类变化的种群的哪些特征会影响其灭绝概率，但针对种群历史在剧烈环境变化中对灭绝概率的作用，相关探究仍较为有限。本研究将在良性环境中经历选择的种群，与在1种或2种胁迫环境中经历选择的种群的灭绝风险进行了比较。我们将来自这三种不同历史背景的莱茵衣藻（Chlamydomonas reinhardtii）的孢子与株系，暴露于一系列剧烈环境变化条件下。研究发现，相较于在良性环境中经历选择的种群，在胁迫环境中经历选择的种群的灭绝风险更高，且该效应并非由初始种群规模差异所致。最后，同一历史背景下的灭绝速率具有高度可重复性，这表明灭绝风险存在显著的历史偶然性。因此，种群的选择历史信息可用于预测其在环境变化过程中的灭绝概率。