Miller Ian, Bruns Emily
Department of Biology, University of Virginia, Charlottesville, VA 22904, USA Biology Distinguished Majors Program, University of Virginia, Charlottesville, VA 22904, USA.
Department of Biology, University of Virginia, Charlottesville, VA 22904, USA
Proc Biol Sci. 2016 Feb 10;283(1824). doi: 10.1098/rspb.2015.3035.
The evolution of separate males and females is an important evolutionary transition that has occurred multiple times in flowering plants. While empirical studies have stressed the potential importance of natural enemies and organismal interactions in the evolution of separate sexes, there has been no treatment of natural enemies in the theoretical literature. We investigated the effects of disease on the evolution of females in gynodioecious populations composed of females and hermaphrodites, where sex is determined by the interaction of cytoplasmic male sterility (CMS) and nuclear restorer genes. When females are significantly more resistant than hermaphrodites, disease drives an increase in the frequency of females and sex determination becomes nuclear, creating the pre-conditions for the evolution of separate males and females. However, when females are only moderately more resistant, disease drives changes in the frequency of CMS and restorer alleles, but has little effect on the frequency of females. We discuss our results in the context of the evolution of mating systems and cyto-nuclear epistasis.
雌雄异体的进化是开花植物中多次发生的重要进化转变。虽然实证研究强调了天敌和生物相互作用在性别进化中的潜在重要性，但理论文献中尚未涉及天敌。我们研究了疾病对由雌性和雌雄同体组成的雌全异株种群中雌性进化的影响，其中性别由细胞质雄性不育（CMS）和核恢复基因的相互作用决定。当雌性比雌雄同体具有显著更高的抗性时，疾病会促使雌性频率增加，性别决定变为核遗传，为雌雄异体的进化创造了先决条件。然而，当雌性仅具有适度更高的抗性时，疾病会推动CMS和恢复等位基因频率的变化，但对雌性频率影响不大。我们在交配系统进化和核质上位性的背景下讨论了我们的结果。
