Sexual dichromatism drives diversification within a major radiation of African amphibians

Theory predicts that sexually dimorphic traits under strong sexual selection, particularly those involved with intersexual signaling, can accelerate speciation and produce bursts of diversification. Sexual dichromatism (sexual dimorphism in color) is widely used as a proxy for sexual selection and is associated with rapid diversification in several animal groups, yet studies using phylogenetic comparative methods to explicitly test for an association between sexual dichromatism and diversification have produced conflicting results. Sexual dichromatism is rare in frogs, but it is both striking and prevalent in African reed frogs, a major component of the diverse frog radiation termed Afrobatrachia. In contrast to most other vertebrates, reed frogs display female-biased dichromatism in which females undergo color transformation, often resulting in more ornate coloration in females than in males. We produce a robust phylogeny of Afrobatrachia to investigate the evolutionary origins of sexu...

理论预测，受强性选择作用的两性异形性状——尤其是涉及异性信号传递的性状——可加速物种形成并引发多样化爆发。性二色性（sexual dichromatism，即颜色层面的两性异形）常被用作性选择的替代指标，且与多个动物类群的快速多样化相关；然而，使用系统发育比较方法明确检验性二色性与多样化关联的研究却得出了相互矛盾的结果。性二色性在蛙类中较为罕见，但在非洲芦苇蛙中既显著又普遍——后者是被称为Afrobatrachia的多样化蛙类辐射类群的主要组成部分。与大多数脊椎动物不同，芦苇蛙表现出雌性偏向的二色性：雌性会发生颜色转变，通常使雌性比雄性具有更华丽的色彩。我们构建了Afrobatrachia的稳健系统发育树，以研究性……