Data from: 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 sexual dichromatism in this radiation and examine
whether the presence of dichromatism is associated with increased rates of
net diversification. We find that sexual dichromatism evolved once within
hyperoliids and was followed by numerous independent reversals to
monochromatism. We detect significant diversification rate heterogeneity
in Afrobatrachia and find that sexually dichromatic lineages have double
the average net diversification rate of monochromatic lineages. By
conducting trait simulations on our empirical phylogeny, we demonstrate
our inference of trait-dependent diversification is robust. Although
sexual dichromatism in hyperoliid frogs is linked to their rapid
diversification and supports macroevolutionary predictions of speciation
by sexual selection, the function of dichromatism in reed frogs remains
unclear. We propose that reed frogs are a compelling system for studying
the roles of natural and sexual selection on the evolution of sexual
dichromatism across both micro- and macroevolutionary timescales.