title: Sexual selection and population divergence II. Divergence in different sexual traits and signal modalities in field crickets (Teleogryllus oceanicus).
abstract: Sexual selection can target many different types of traits. However, the relative influence of different sexually selected traits during evolutionary divergence is poorly understood. We used the field cricket Teleogryllus oceanicus to quantify and compare how five traits from each of three sexual signal modalities and components diverge among allopatric populations: male advertisement song, cuticular hydrocarbon (CHC) profiles and forewing morphology. Population divergence was unexpectedly consistent: we estimated the among-population (genetic) variance-covariance matrix, D, for all 15 traits, and Dmaxexplained nearly two-thirds of its variation. CHC and wing traits were most tightly integrated, whereas song varied more independently. We modeled the dependence of among-population trait divergence on genetic distance estimated from neutral markers to test for signatures of selection versus neutral divergence. For all three sexual trait types, phenotypic variation among populations was largely explained by a neutral model of divergence. Our findings illustrate how phenotypic integration across different types of sexual traits might impose constraints on the evolution of mating isolation and divergence via sexual selection.
authors.affiliation: Department of Zoology, University of Cambridge, Cambridge, CB2 3EJ, United Kingdom.
authors.forename: Sonia
authors.initials: S
authors.lastname: Pascoal
authors.affiliation: Institute of Environmental Sciences, Jagellonian University, Gronostajova 7, 30-387, Kraków, Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Mendrok
authors.affiliation: Centre for Ecology and Conservation, School of Biosciences, University of Exeter, Cornwall Campus, TR10 9EZ, United Kingdom.
authors.forename: Alastair J
authors.initials: AJ
authors.lastname: Wilson
authors.affiliation: Centre for Ecology and Conservation, School of Biosciences, University of Exeter, Cornwall Campus, TR10 9EZ, United Kingdom.|School of Science and Health and Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW 2751, Australia.
authors.forename: John
authors.initials: J
authors.lastname: Hunt
authors.affiliation: Centre for Biological Diversity, University of St Andrews, St. Andrews, KY16 9TH, United Kingdom.
authors.forename: Nathan W
authors.initials: NW
authors.lastname: Bailey
mesh_terms: D000818:Animals; D014644:Genetic Variation; D006135:Gryllidae; D006838:Hydrocarbons; D008297:Male; D010641:Phenotype; D012641:Selection, Genetic; D014921:Wings, Animal
chemical_list: D006838:Hydrocarbons
keywords: acoustic communication; cuticular hydrocarbons; eigendecomposition; geometric morphometrics; multimodal signaling; sexual selection