Despite the theory that sexually dimorphic traits under strong sexual selection lead to rapid diversification, phylogenetic studies testing for correlations between sexual dichromatism (sexual differences based on coloration and pattern) and diversification have had mixed results. Although sexual dichromatism is rare in most frogs, it is common in the species-rich African reed frogs (Family Hyperoliidae) with females being more strikingly ornate than males. Portik et al. (2019) examined the group to better understand the evolutionary origins of sexual dichromatism and how it relates to their diversification. Sexual dichromatism evolved once followed by multiple reversals to monochromatism. Clades displaying dichromatism had about double the rates of diversification of monochromatic clades. African reed frogs are a promising group for exploring the role of natural and sexual selection on the evolution of sexual dichromatism.
