Data from: Environmental stress correlates with increases in both genetic and residual variances: a meta-analysis of animal studies

Adaptive evolutionary responses are determined by the strength of selection and the amount of genetic variation within traits, however, both are known to vary across environmental conditions. As selection is generally expected to be strongest under stressful conditions, understanding how the expression of genetic variation changes across stressful and benign environmental conditions is crucial for predicting the rate of adaptive change. While theory generally predicts increased genetic variation under stress, previous syntheses of the field has found limited support for this notion. These studies have focused on heritability, which is dependent on other environmentally sensitive, but non-genetic, sources of variation. Here, we aim to complement these studies with a meta-analysis where we examine changes in coefficient of variation (CV) in maternal, genetic, and residual variances across stressful and benign conditions. Confirming previous analyses, we did not find any clear direction in how heritability changes across stressful and benign conditions. However, when analyzing CV, we found higher genetic and residual variance under highly stressful conditions in life-history traits but not in morphological traits. Our findings are of broad significance to contemporary evolution suggesting that rapid evolutionary adaptive response may be mediated by increased evolutionary potential in stressed populations.适应性进化响应由选择强度与性状内的遗传变异量共同决定，而二者均已知随环境条件发生变化。通常认为，选择强度在胁迫环境下达到最强，因此解析遗传变异的表达如何随胁迫与适宜环境发生改变，对预测适应性进化速率至关重要。尽管理论普遍预测胁迫环境下遗传变异会有所增加，但此前该领域的综合研究并未为这一观点提供充分支持。此类研究多聚焦于遗传力，而遗传力依赖于其他对环境敏感的非遗传变异来源。本研究旨在通过荟萃分析补充此类研究，考察母性方差、遗传方差与残差方差在胁迫与适宜环境下的变化情况。与此前的分析结果一致，我们未发现遗传力随胁迫与适宜环境变化存在明确趋势。然而，在分析变异系数（coefficient of variation, CV）时，我们发现生活史性状在重度胁迫环境下的遗传方差与残差方差显著更高，但形态性状并未呈现这一规律。本研究结果对现代进化生物学具有广泛意义，表明快速进化的适应性响应或可通过受胁迫种群中进化潜力的提升得以介导。