Department of Biology, Indiana University, 1001 East 3rd Street, Bloomington, IN 47405, USA.
Department of Biology, Texas A&M University, College Station, TX 77843, USA.
J Hered. 2022 Feb 17;113(1):48-53. doi: 10.1093/jhered/esab055.
We use population genetics to model the evolution of a gene with an indirect effect owing to paternal care and with a second pleiotropic, direct effect on offspring viability. We use the model to illustrate how the common empirical practice of considering offspring viability as a component of parent fitness can confound a gene's direct and indirect fitness effects. We investigate when this confounding results in a distorted picture of overall evolution and when it does not. We find that the practice has no effect on mean fitness, W, but it does have an effect on the dynamics of gene frequency change, ∆q. We also find that, for some regions of parameter space associated with fitness trade-offs, the distortion is not only quantitative but also qualitative, obscuring the direction of gene frequency change. Because it affects the evolutionary dynamics, it also affects the expected amount of genetic variation at mutation-selection balance, an important consideration in molecular evolution. We discuss empirical techniques for separating direct from indirect effects and how field studies measuring the value of male paternal care might be improved by using them.
我们利用群体遗传学来模拟一个基因的进化，该基因由于父代抚育而具有间接效应，并且对后代生存力具有第二个性状直接效应。我们使用该模型来说明为什么将后代生存力作为亲代适合度的一个组成部分的常见经验法则可能会混淆基因的直接和间接适合度效应。我们研究了当这种混淆导致整体进化的扭曲以及何时不会导致扭曲的情况。我们发现这种做法对平均适合度 W 没有影响，但它确实会影响基因频率变化 ∆q 的动态。我们还发现，对于与适合度权衡相关的某些参数空间区域，这种扭曲不仅是定量的，而且是定性的，掩盖了基因频率变化的方向。由于它影响了进化动力学，因此也会影响突变选择平衡时遗传变异的预期数量，这是分子进化中的一个重要考虑因素。我们讨论了将直接效应和间接效应分开的经验技术，以及如何通过使用这些技术来改进测量雄性亲代抚育价值的实地研究。
