title: Lack of phonotactic preferences of female frogs and its consequences for signal evolution.
abstract: Sexual selection is one of the main evolutionary forces that drive signal evolution. In previous studies, we have found out that males of Pleurodema thaul, a frog with an extensive latitudinal distribution in Chile, emits advertisement calls that show remarkable variation among populations. In addition, this variation is related to intense inter-male acoustic competition (intra-sexual selection) occurring within each population. However, the extent to which female preferences contribute to the signal divergence observed is unclear. To study the responsiveness of females in each population, we stimulated females with synthetic calls designed with the acoustic structure of their own population and subsequently responsive females were subjected to a two-choice experiment, where they were stimulated with synthetic calls of their own population versus a call of a foreign population. Females do not show phonotactic preferences for calls of their own or foreign populations as measured with both linear and circular variables. The lack of phonotactic preferences suggests an absence of participation of inter-sexual selection processes in the divergence of the acoustic signals of P. thaul, highlighting the importance of intra-sexual selection for the evolution of these signals. These results concur with studies in other vertebrates emphasizing the relevance of interactions among males for the evolution of acoustic communication systems.
authors.affiliation: Programa de Fisiología y Biofísica, ICBM, Facultad de Medicina, Universidad de Chile, Independencia 1027, Santiago, Chile; Facultad de Ciencias Básicas, Universidad Católica del Maule, San Miguel 3605, 3480112 Talca, Chile. Electronic address: nvelasquez@ucm.cl.
authors.forename: Nelson A
authors.initials: NA
authors.lastname: Velásquez
authors.affiliation: Programa de Fisiología y Biofísica, ICBM, Facultad de Medicina, Universidad de Chile, Independencia 1027, Santiago, Chile.
authors.forename: Jose Luis
authors.initials: JL
authors.lastname: Valdés
authors.affiliation: Instituto de Ecología y Biodiversidad, Universidad de Chile, Las Palmeras 3425, Santiago, Chile.
authors.forename: Rodrigo A
authors.initials: RA
authors.lastname: Vásquez
authors.affiliation: Programa de Fisiología y Biofísica, ICBM, Facultad de Medicina, Universidad de Chile, Independencia 1027, Santiago, Chile.
authors.forename: Mario
authors.initials: M
authors.lastname: Penna
mesh_terms: D000161:Acoustic Stimulation; D000162:Acoustics; D000818:Animals; D001001:Anura / Q000502:physiology*; D001522:Behavior, Animal / Q000502:physiology*; D005075:Biological Evolution; D005260:Female; D008297:Male; D052586:Mating Preference, Animal / Q000502:physiology; D014828:Vocalization, Animal / Q000502:physiology*
keywords: Female choice; Geographic variation; Sexual selection