01753nas a2200181   4500008004600000245008100046210006900127520118800196653001701384653001001401653001801411653000901429100002201438700002201460700002001482700002101502856004801523       Submitted                   eng d     00aFemales alter their song when challenged in a sex-role reversed bird species0 aFemales alter their song when challenged in a sexrole reversed b3 aAbstract&nbsp;&nbsp;Birdsong serves to attract mates and to deter territorial rivals. Even though song is not restricted to males, this dual function has almost exclusively been demonstrated for male song. To test the generality of hypotheses on birdsong, we investigated female song in the sex-role reversed, classically polyandrous African black coucal (Centropus grillii) in the context of female–female competition. We compared spontaneously vocalizing females with females vocally responding to a playback simulating a conspecific intruder. Females changed vocal parameters in response to playbacks: They lowered the pitch of their vocalizations and enhanced the duration of song elements when being challenged. Also, the composition of the vocalizations was altered. There was no significant correlation between pitch and body size parameters in spontaneous song, but there was for response songs, with larger females having a lower pitch. These changes in vocal properties suggest that the vocalizations are important for mutual assessment of competitive abilities in females. Our findings confirm the general role of intrasexual competition in vocal communication of birds.10abioacoustics10abirds10acommunication10asong1 aGeberzahn, Nicole1 aGoymann, Wolfgang1 aMuck, Christina1 aCate, Carel, ten  uhttp://dx.doi.org/10.1007/s00265-009-0836-001982nas a2200241   4500008004100000245010900041210006900150260000800219300001400227490000700241520125600248653001701504653001801521653000901539653001801548100002801566700002401594700001801618700001701636700002101653700002201674856004401696       2010                        eng d00aSounds of male Lake Victoria cichlids vary within and between species and affect female mate preferences0 aSounds of male Lake Victoria cichlids vary within and between sp  cMay  a548–5550 v213 aSound production in fish is widespread and occurs in several contexts, such as species recognition, mate choice, and aggression. However, there is little experimental evidence for the importance of acoustic signals in social contexts and the influence of sound on mating decisions of females. Cichlid fish are known for their bright nuptial coloration, which plays an important role in mate choice and reproductive isolation between the many species of cichlid fish in East Africa. They also produce sounds in both aggressive and courtship interactions. In this study, we show that the sounds produced by males of Lake Victoria cichlids are species specific. There is also a correlation between fish size and peak frequency of sounds across species. We did not find context-dependent differences within a species (Pundamilia nyererei) between male sounds produced during aggressive displays toward males or sexual displays toward females. We also show with playback experiments that courtship sounds influence the mate preferences of female cichlids. In combination with many studies in the literature on visual signaling, our results suggest that multimodal communication plays an important role in sexual selection in cichlids. 10.1093/beheco/arq01810abioacoustics10acommunication10afish10aintraspecific1 aVerzijden, Machteld, N.1 avan Heusden, Jasper1 aBouton, Niels1 aWitte, Frans1 aCate, Carel, ten1 aSlabbekoorn, Hans  uhttp://dx.doi.org/10.1093/beheco/arq018