Data from: Eco-evolutionary feedback promotes Red Queen dynamics and selects for sex in predator populations

Although numerous hypotheses exist to explain the overwhelming presence of sexual reproduction across the tree of life, we still cannot explain its prevalence when considering all inherent costs involved. The Red Queen hypothesis states that sex is maintained because it can create novel genotypes with a selective advantage. This occurs when the interactions between species induce frequent environmental change. Here we investigate whether coevolution and eco-evolutionary feedback dynamics in a predator-prey system allows for indirect selection and maintenance of sexual reproduction in the predator. Combining models and chemostat experiments of a rotifer-algae system we show a continuous feedback between population and trait change along with recurrent shifts from selection by predation and competition for a limited resource. We found that a high propensity for sex was indirectly selected and was maintained in rotifer populations within environments containing these eco-evolutionary dynamics; whereas within environments under constant conditions, predators evolved rapidly to lower levels of sex. Thus, our results indicate that the influence of eco-evolutionary feedback dynamics on the overall evolutionary change has been underestimated.

尽管已有诸多假说试图阐释有性生殖在整个生命之树中无处不在的现象，但在综合考量其所有内在代价后，我们仍无法解释其为何如此普遍。红皇后假说（Red Queen hypothesis）指出，有性生殖得以维持的原因在于其能够产生具有选择优势的全新基因型。当物种间的相互作用引发频繁的环境变化时，这一效应便会显现。本研究旨在探究捕食者-猎物系统中的协同进化与生态进化反馈动力学，是否能够让捕食者种群产生间接选择并维持有性生殖。结合轮虫-藻类系统的模型与恒化器实验，我们发现种群与性状变化间存在持续的反馈机制，同时伴随捕食选择与有限资源竞争带来的周期性选择压力偏移。我们发现，在存在这类生态进化反馈动力学的环境中，轮虫种群的高有性生殖倾向受到了间接选择并得以维持；而在环境恒定的对照组中，捕食者种群快速进化出更低的有性生殖水平。综上，本研究结果表明，生态进化反馈动力学对整体进化过程的影响此前被低估了。