Behavioural Ecology, Department of Biology, Ludwig-Maximilians University of Munich, Planegg-Martinsried, Germany.
School of Biological Sciences, University of Queensland, St Lucia, Australia.
Evolution. 2019 Sep;73(9):1809-1820. doi: 10.1111/evo.13802. Epub 2019 Jul 26.
Ecological conditions such as nutrition can change genetic covariances between traits and accelerate or slow down trait evolution. As adaptive trait correlations can become maladaptive following rapid environmental change, poor or stressful environments are expected to weaken genetic covariances, thereby increasing the opportunity for independent evolution of traits. Here, we demonstrate the differences in genetic covariance among multiple behavioral and morphological traits (exploration, aggression, and body weight) between southern field crickets (Gryllus bimaculatus) raised in favorable (free-choice) versus stressful (protein-deprived) nutritional environments. We also quantify the extent to which differences in genetic covariance structures contribute to the potential for the independent evolution of these traits. We demonstrate that protein-deprived environments tend to increase the potential for traits to evolve independently, which is caused by genetic covariances that are significantly weaker for crickets raised on protein-deprived versus free-choice diets. The weakening effects of stressful environments on genetic covariances tended to be stronger in males than in females. The weakening of the genetic covariance between traits under stressful nutritional environments was expected to facilitate the opportunity for adaptive evolution across generations. Therefore, the multivariate gene-by-environment interactions revealed here may facilitate behavioral and morphological adaptations to rapid environmental change.
生态条件，如营养，可以改变性状之间的遗传协方差，并加速或减缓性状进化。由于适应性状相关性在快速环境变化后可能变得不适应，因此较差或压力环境预计会削弱遗传协方差，从而增加性状独立进化的机会。在这里，我们展示了在有利（自由选择）和压力（蛋白质缺乏）营养环境下饲养的南方蟋蟀（ Gryllus bimaculatus ）之间多个行为和形态特征（探索、攻击和体重）之间遗传协方差的差异。我们还量化了遗传协方差结构的差异在多大程度上有助于这些特征独立进化的潜力。我们表明，蛋白质缺乏环境往往会增加性状独立进化的潜力，这是由于在蛋白质缺乏饮食下饲养的蟋蟀的遗传协方差明显较弱。压力环境对遗传协方差的削弱作用在雄性中比在雌性中更强。在压力营养环境下，性状之间遗传协方差的减弱预计将促进跨代的适应性进化机会。因此，这里揭示的多变量基因与环境相互作用可能有助于行为和形态对快速环境变化的适应。
