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Sexual Dichromatism Drives Diversification within a Major Radiation of African Amphibians.

ABSTRACT: 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 that 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 micro- and macroevolutionary timescales.

SUBMITTER: Portik DM

PROVIDER: S-EPMC6934645 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Sexual Dichromatism Drives Diversification within a Major Radiation of African Amphibians.

Portik Daniel M DM Bell Rayna C RC Blackburn David C DC Bauer Aaron M AM Barratt Christopher D CD Branch William R WR Burger Marius M Channing Alan A Colston Timothy J TJ Conradie Werner W Dehling J Maximilian JM Drewes Robert C RC Ernst Raffael R Greenbaum Eli E Gvoždík Václav V Harvey James J Hillers Annika A Hirschfeld Mareike M Jongsma Gregory F M GFM Kielgast Jos J Kouete Marcel T MT Lawson Lucinda P LP Leaché Adam D AD Loader Simon P SP Lötters Stefan S Meijden Arie Van Der AV Menegon Michele M Müller Susanne S Nagy Zoltán T ZT Ofori-Boateng Caleb C Ohler Annemarie A Papenfuss Theodore J TJ Rößler Daniela D Sinsch Ulrich U Rödel Mark-Oliver MO Veith Michael M Vindum Jens J Zassi-Boulou Ange-Ghislain AG McGuire Jimmy A JA

Systematic biology 20191101 6

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 diversificati ...[more]

PMID: 31140573

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Dataset Information

Sexual Dichromatism Drives Diversification within a Major Radiation of African Amphibians.

Publications

Sexual Dichromatism Drives Diversification within a Major Radiation of African Amphibians.

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