Parasites are known to be a key driving force in mate choice and are important for the expression and evolution of ornaments and behavioral traits being used.However,there is little experimental evidence on how the pa...Parasites are known to be a key driving force in mate choice and are important for the expression and evolution of ornaments and behavioral traits being used.However,there is little experimental evidence on how the parasite’s burden of the choosing individual is integrated into the mate-choice process and how it affects decision-making,especially in relation to parasite infestation of potential mates.Thus,the aim of our study was to determine whether female house sparrows Passer domesticus adjust their mate preference according to their own as well as the parasite load of prospective partners.To do this,we experimentally manipulated female parasite load and determined their mate preferences prior to and after parasite treatment.We manipulated the chronic coccidian parasite burden of females either by initiating the acute infection phase via re-infecting them with coccidian or by temporally reducing the parasite load of coccidia.We then measured the effect of this manipulation on mate preference by presenting females with a choice of four stimuli:three males with similar ornaments,but unmanipulated,naturally varying chronic coccidiosis levels,and an unmanipulated control female.Additionally,we recorded some males’behavior in relation to their infection status pointing toward an increased or reduced interest in mating.We found that females preferred highly infested males prior to manipulation,regardless of their own infestation level.However,after manipulation,infested females avoided highly infested males probably in response to the deterioration of their health condition by parasites.Our study suggests that mate-choice decisions are more complex when they are mediated by parasites.The implications of parasites for evolutionary theories of sexual signaling and mate choice are discussed.展开更多
In the last decades, higher attention has been paid to olfactory perception in birds. As a consequence, a handful of avian species have been discovered to use olfaction in different contexts. Nevertheless, we still ha...In the last decades, higher attention has been paid to olfactory perception in birds. As a consequence, a handful of avian species have been discovered to use olfaction in different contexts. Nevertheless, we still have a very limited knowledge about the use of odor cues in avian social life, particularly, in the case of songbirds. Here, we investigate if female house sparrows Passer domesticus show any preference for the odor of kin and nonkin conspecifics and we also test a possible role of familiarity based on male see nt in female choice. We performed the experiment with captive birds twice, duri ng the non breeding and breedi ng seas ons. Our results show that female house sparrows strongly avoided the odor of unrelated familiar (UF) males, both in the breeding and nonbreeding seasons. Our results suggest recognition for olfactory stimuli related to familiarity and kin ship. We suggest that avoidance for UF males is associated with previous experie nee in this species. Also, we provided further evidenee to the use of olfaction in passerine species by using a new experimental setup.展开更多
The quality of a breeding site may have major fitness consequences.A fundamental step to understanding the process of nest-site selection is the identification of the information individuals use to choose high-quality...The quality of a breeding site may have major fitness consequences.A fundamental step to understanding the process of nest-site selection is the identification of the information individuals use to choose high-quality nest sites.For secondary cavity-nesting bird species that do not add nest lining material,organic remains (faeces,pellets)accumulated inside nest cavities during previous breeding events may be a cue for high-quality nest-sites,as they contain information about past successful breeding and may improve thermal insulation of eggs during incubation.However,cavities in which breeding was successful might also contain more nest-dwelling ectoparasites than unoccupied cavities, offering an incentive for prospective parents to avoid them.We exposed breeding cavity-nesting lesser kestrels (Falco naumanni)to nestbox dyads consisting of a dirty (with a thick layer of organic substrate) and a clean nestbox (without organic material).Dirty nestboxes were strongly preferred,being occupied earlier and more frequently than clean ones.Hatching success in dirty nestboxes was significantly higher than in clean ones,suggesting a positive effect of organic nest material on incubation efficiency, while nestbox dirtiness did not significantly affect clutch and brood size.Nestlings from dirty nestboxes had significantly higher ectoparasite load than those from clean nestboxes soon after egg hatching,but this difference was not evident a few days later.Nest substrate did not significantly affect nestling growth.We concluded that nest substrate is a key driver of nest-site choice in lesser kestrels,although the adaptive value of such a strong preference appears elusive and may be context-dependent.展开更多
文摘Parasites are known to be a key driving force in mate choice and are important for the expression and evolution of ornaments and behavioral traits being used.However,there is little experimental evidence on how the parasite’s burden of the choosing individual is integrated into the mate-choice process and how it affects decision-making,especially in relation to parasite infestation of potential mates.Thus,the aim of our study was to determine whether female house sparrows Passer domesticus adjust their mate preference according to their own as well as the parasite load of prospective partners.To do this,we experimentally manipulated female parasite load and determined their mate preferences prior to and after parasite treatment.We manipulated the chronic coccidian parasite burden of females either by initiating the acute infection phase via re-infecting them with coccidian or by temporally reducing the parasite load of coccidia.We then measured the effect of this manipulation on mate preference by presenting females with a choice of four stimuli:three males with similar ornaments,but unmanipulated,naturally varying chronic coccidiosis levels,and an unmanipulated control female.Additionally,we recorded some males’behavior in relation to their infection status pointing toward an increased or reduced interest in mating.We found that females preferred highly infested males prior to manipulation,regardless of their own infestation level.However,after manipulation,infested females avoided highly infested males probably in response to the deterioration of their health condition by parasites.Our study suggests that mate-choice decisions are more complex when they are mediated by parasites.The implications of parasites for evolutionary theories of sexual signaling and mate choice are discussed.
文摘In the last decades, higher attention has been paid to olfactory perception in birds. As a consequence, a handful of avian species have been discovered to use olfaction in different contexts. Nevertheless, we still have a very limited knowledge about the use of odor cues in avian social life, particularly, in the case of songbirds. Here, we investigate if female house sparrows Passer domesticus show any preference for the odor of kin and nonkin conspecifics and we also test a possible role of familiarity based on male see nt in female choice. We performed the experiment with captive birds twice, duri ng the non breeding and breedi ng seas ons. Our results show that female house sparrows strongly avoided the odor of unrelated familiar (UF) males, both in the breeding and nonbreeding seasons. Our results suggest recognition for olfactory stimuli related to familiarity and kin ship. We suggest that avoidance for UF males is associated with previous experie nee in this species. Also, we provided further evidenee to the use of olfaction in passerine species by using a new experimental setup.
文摘The quality of a breeding site may have major fitness consequences.A fundamental step to understanding the process of nest-site selection is the identification of the information individuals use to choose high-quality nest sites.For secondary cavity-nesting bird species that do not add nest lining material,organic remains (faeces,pellets)accumulated inside nest cavities during previous breeding events may be a cue for high-quality nest-sites,as they contain information about past successful breeding and may improve thermal insulation of eggs during incubation.However,cavities in which breeding was successful might also contain more nest-dwelling ectoparasites than unoccupied cavities, offering an incentive for prospective parents to avoid them.We exposed breeding cavity-nesting lesser kestrels (Falco naumanni)to nestbox dyads consisting of a dirty (with a thick layer of organic substrate) and a clean nestbox (without organic material).Dirty nestboxes were strongly preferred,being occupied earlier and more frequently than clean ones.Hatching success in dirty nestboxes was significantly higher than in clean ones,suggesting a positive effect of organic nest material on incubation efficiency, while nestbox dirtiness did not significantly affect clutch and brood size.Nestlings from dirty nestboxes had significantly higher ectoparasite load than those from clean nestboxes soon after egg hatching,but this difference was not evident a few days later.Nest substrate did not significantly affect nestling growth.We concluded that nest substrate is a key driver of nest-site choice in lesser kestrels,although the adaptive value of such a strong preference appears elusive and may be context-dependent.
