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偏好演化，仍是性选择（sexual selection）研究领域中极具争议的议题。其中一个被称为择偶悖论（lek paradox）的经典难题，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（natural selection）与性选择，遗传质量的变异仍得以维持的内在机制。本研究从理论层面探究了这样一种情景：雌性需付出直接适合度成本（fitness cost），以规避携带常染色体分离扭曲因子（autosomal segregation distorter）的雄性。研究结果显示，此类情景可极大地推动择偶偏好的演化进程。由于该扭曲因子以非孟德尔式遗传（non-Mendelian fashion）的方式传递，即便存在定向性选择（directional sexual selection），它仍可在种群中持续维持。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（choice allele）诱导出过强的择偶偏好，或是扭曲效应过于强烈，偏好的演化会受到显著限制。此外，仅当存在能够可靠指示雄性携带该扭曲因子基因型的信号时，该择偶偏好才能得以维持。因此，即便在择偶悖论未发挥主要作用的演化系统中，具有适合度成本的雌性择偶偏好也仅能在特定条件下得以扩散。我们还探讨了分离扭曲系统对于具有成本的雌性择偶偏好演化的重要意义，以及人工分离扭曲因子在害虫防控（pest control）中应用的潜在价值。