Data from: The evolution of costly mate choice against segregation distorters

The evolution of female preference for male genetic quality remains a controversial topic in sexual selection research. One well-known problem, known as the lek paradox, lies in understanding how variation in genetic quality is maintained in spite of natural selection and sexual selection against low-quality alleles. Here, we theoretically investigate a scenario where females pay a direct fitness cost to avoid males carrying an autosomal segregation distorter. We show that preference evolution is greatly facilitated under such circumstances. Because the distorter is transmitted in a non-Mendelian fashion, it can be maintained in the population despite directional sexual selection. The preference helps females avoid fitness costs associated with the distorter. Interestingly, we find that preference evolution is limited if the choice allele induces a very strong preference or if distortion is very strong. Moreover, the preference can only persist in the presence of a signal that reliably indicates a male's distorter genotype. Hence, even in a system where the lek paradox does not play a major role, costly preferences can only spread under specific circumstances. We discuss the importance of distorter systems for the evolution of costly female choice and potential implications for the use of artificial distorters in pest control.

雌性对雄性遗传质量的择偶偏好演化，仍是性选择研究领域颇具争议的议题。其中一个广为人知的经典难题即求偶场悖论（lek paradox），其核心在于阐释：尽管存在针对低质量等位基因的自然选择与性选择，种群中为何仍能维持遗传质量的变异。本研究从理论层面构建并分析了一类情境：雌性需付出直接适合度成本，方能规避携带常染色体分离扭曲因子（autosomal segregation distorter）的雄性。研究结果表明，此类情境下择偶偏好的演化会得到极大促进。由于该分离扭曲因子以非孟德尔式遗传模式进行传递，即便存在定向性选择，其仍可在种群中得以存续。该择偶偏好可帮助雌性规避与该扭曲因子相关的适合度成本。值得注意的是，本研究发现：若选择等位基因诱导出过强的择偶偏好，或是分离扭曲效应极强，择偶偏好的演化均会受到限制。此外，唯有当存在能够可靠指示雄性是否携带该扭曲因子基因型的信号时，该择偶偏好方能得以存续。因此，即便在求偶场悖论未发挥主要作用的演化系统中，代价高昂的择偶偏好也仅能在特定条件下得以扩散。本研究最后讨论了分离扭曲系统对代价高昂的雌性择偶选择演化的重要意义，以及人工分离扭曲因子在害虫防治中的潜在应用价值。