Does side matter? The evolution of asymmetric genitalia in livebearing fish

形态上的不对称在两侧对称的生物体中是普遍存在的。简单的左右不对称性有助于生物体之间的比较，从而具有增加我们对进化过程的理解的巨大潜力。特别有希望的是动物生殖器不对称多态性的进化，因为它与适应性密切相关。 性选择在动物生殖器的进化过程中起着重要作用，但具体机制尚不清楚。目前，最合理的解释是神秘的女性选择，男性-男性精子竞争和性对抗共同进化。区分它们是具有挑战性的，因为它们并不相互排斥。另一个局限性是只关注一个或几个物种。 我建议研究生殖器不对称的进化在一组livebearing鱼类使用遗传控制的比较方法。大多数拟眼鲷科的种类都表现为内受精，并且许多种类表现出生殖器不对称。然而，这种不对称性的进化含义在很大程度上仍然没有得到研究。我建议进行一系列的实验，旨在进一步了解的原因和后果的生殖器不对称的Anablepidae。首先，我将产生一个很好的解决基于全基因组标记的生殖器发育，并映射到这个生殖器发育的不对称性，使在Anablepidae生殖器不对称的进化历史的推断。然后，我将在自然群体中进行群体遗传分析，以确定随机交配和群体分化的不对称性的后果。最后，我将进行具体的交叉和系谱分析，以确定健身的后果和生殖器不对称的Anablepidae的遗传基础。

Morphological asymmetries are ubiquitous among otherwise bilaterally symmetric organisms. The simple left-right nature of asymmetry facilitates comparisons across organisms, thus holding great potential to increase our understanding of evolutionary processes. Particularly promising is the evolution of asymmetric polymorphisms in animal genitalia, because of its strong correlation with fitness. It is now clear that sexual selection plays a fundamental role in the evolution of animal genitalia; however, the specific mechanisms are still unclear. Currently, the most plausible explanations are cryptic female choice, male-male sperm competition, and sexually antagonistic coevolution. Distinguishing among them is challenging because these are not mutually exclusive. Another limitation has been the focus on a single or few species. I propose to study the evolution of genital asymmetry in a group of livebearing fishes using phylogenetically controlled comparative methods. Most species in Anablepidae show internal fertilization, and many species exhibit genital asymmetry. Yet, the evolutionary implications of this asymmetry remain largely unstudied. I propose to conduct a series of experiments aimed to further our understanding of the causes and consequences of genital asymmetry in Anablepidae. First, I will produce a well-resolved phylogeny based on genome-wide markers, and map asymmetry into this phylogeny to make inference on the evolutionary history of genital asymmetry in Anablepidae. Then, I will conduct population genetic analyses in natural populations to determine the consequences of asymmetry for random mating and population differentiation. Finally, I will conduct specific crosses and pedigree analyses to determine the fitness consequences and genetic bases of genital asymmetry in Anablepidae.