Many animals use color to signal their quality and/or behavioral motivations.Colorful signals have been well studied in the contexts of competi-tion and mate choice;however,the role of these signals in nonsexual,affil...Many animals use color to signal their quality and/or behavioral motivations.Colorful signals have been well studied in the contexts of competi-tion and mate choice;however,the role of these signals in nonsexual,affiliative relationships is not as well understood.Here,we used wild social groups of the cichlid fish Neolamprologus pulcher to investigate whether the size of a brightly colored facial patch was related to 1)individual quality,2)social dominance,and/or 3)affiliative relationships.Individuals with larger patches spent more time foraging and tended to perform more aggressive acts against conspecific territory intruders.We did not find any evidence that the size of these yellow patches was related to social rank or body size,but dominant males tended to have larger patches than dominant females.Additionally,patch size had a rank-specific relationship with the number of affiliative interactions that individuals engaged in.Dominant males with large patches received fewer affiliative acts from their groupmates compared to dominant males with small patches.However,subordinates with large patches tended to receive more affiliative acts from their groupmates while performing fewer affiliative acts themselves.Taken together,our results suggest that patch size reflects interindividual variation in foraging effort in this cichlid fish and offer some of the first evidence that colorful signals may shape affiliative relationships withinwildsocialgroups.展开更多
Understanding how animals select their mates requires knowing the factors that shape mate preferences.Recent theoretical and empirical considerations suggest that female mating status can influence the degree to which...Understanding how animals select their mates requires knowing the factors that shape mate preferences.Recent theoretical and empirical considerations suggest that female mating status can influence the degree to which a female engages in mate choice,with virgin females predicted to be less choosy than mated females.In this study,we investigated mate choice in both virgin and mated females in the pygmy halfbeak Dermogenys collettei.Halfbeaks are small,live-bearing,internally fertilizing freshwater fish that live in mixed-sex groups where females have ample opportunity to engage in mate choice.Using a dichotomous choice assay,we quantified and contrasted in virgin and mated females mate preferences for differences in male body size,beak size,and area of yellow and red coloration.We also examined how mating status influenced the amount of time a female associated with the first male encountered and the relative amount of time a female associated with each male.We demonstrate that mate preferences of female halfbeaks are driven primarily by the size of red coloration present on males.Females showed contrasting preferences based on mating status,with virgin females preferentially associating with drab males whereas mated females preferentially associate with males possessing large areas of red.Contrary to expectations,female mating status did not influence how females associate with the first males encountered or how females biased their association time among males.Although the precise drivers of these effects need further studying,our finding highlights a possible explanation for how variation in male ornamentation can be maintained.展开更多
基金supported by a Natural Sciences and Engineering Research Council of Canada(NSERC)Discovery grant provided to SB(RGPIN-2016-05772)the National Science Foundation under grant No.1557836 provided to IMH.
文摘Many animals use color to signal their quality and/or behavioral motivations.Colorful signals have been well studied in the contexts of competi-tion and mate choice;however,the role of these signals in nonsexual,affiliative relationships is not as well understood.Here,we used wild social groups of the cichlid fish Neolamprologus pulcher to investigate whether the size of a brightly colored facial patch was related to 1)individual quality,2)social dominance,and/or 3)affiliative relationships.Individuals with larger patches spent more time foraging and tended to perform more aggressive acts against conspecific territory intruders.We did not find any evidence that the size of these yellow patches was related to social rank or body size,but dominant males tended to have larger patches than dominant females.Additionally,patch size had a rank-specific relationship with the number of affiliative interactions that individuals engaged in.Dominant males with large patches received fewer affiliative acts from their groupmates compared to dominant males with small patches.However,subordinates with large patches tended to receive more affiliative acts from their groupmates while performing fewer affiliative acts themselves.Taken together,our results suggest that patch size reflects interindividual variation in foraging effort in this cichlid fish and offer some of the first evidence that colorful signals may shape affiliative relationships withinwildsocialgroups.
基金a Swedish Research Council(Vetenskapsradet)grant to J.L.F(2017-04680)a Wenner-Gren Foundation fellowship to A.D.,and a Wallenberg Academy Fellowship(Knut och Alice Wallenbergs Stiftelse)to J.L.F.B.M.C.was supported by the Canadian Graduate Scholarship and Michael Smith Foreign Study Supplements programs provided by the Natural Sciences and Engineering Research Council of Canada(NSERC).
文摘Understanding how animals select their mates requires knowing the factors that shape mate preferences.Recent theoretical and empirical considerations suggest that female mating status can influence the degree to which a female engages in mate choice,with virgin females predicted to be less choosy than mated females.In this study,we investigated mate choice in both virgin and mated females in the pygmy halfbeak Dermogenys collettei.Halfbeaks are small,live-bearing,internally fertilizing freshwater fish that live in mixed-sex groups where females have ample opportunity to engage in mate choice.Using a dichotomous choice assay,we quantified and contrasted in virgin and mated females mate preferences for differences in male body size,beak size,and area of yellow and red coloration.We also examined how mating status influenced the amount of time a female associated with the first male encountered and the relative amount of time a female associated with each male.We demonstrate that mate preferences of female halfbeaks are driven primarily by the size of red coloration present on males.Females showed contrasting preferences based on mating status,with virgin females preferentially associating with drab males whereas mated females preferentially associate with males possessing large areas of red.Contrary to expectations,female mating status did not influence how females associate with the first males encountered or how females biased their association time among males.Although the precise drivers of these effects need further studying,our finding highlights a possible explanation for how variation in male ornamentation can be maintained.
