Kristin Hubakk, Zachariah Wylde, Russell Bonduriansky
Environmental factors such as dietary nutrients can shape the expression of developmentally plastic sexual traits in many species. However, while there has been extensive research into the developmental plasticity of sexual traits at the individual level, the broader consequences of this variation at the population scale remain poorly understood. Here, we asked whether plastic responses to the developmental environment can shape sexual competition and initiate reproductive isolation between populations. We reared neriid flies, Telostylinus angusticollis, on nutrient-rich and nutrient-poor larval diets, generating adult flies that differed in body size and secondary sexual trait expression. We then investigated sexual competition in experimental populations from each developmental environment, and tested for reproductive isolation between flies from mismatched environments. We found that, compared with poor-diet populations, rich-diet populations exhibited more frequent and escalated male-male combat and more frequent mating and mate-guarding. However, we found no evidence that sexual selection was affected by the developmental environment. Mismatched female-male pairs tended to take longer to mate and rich-diet females often rejected poor-diet males, but mismatched pairs were not less likely to mate within 1 hour or produce viable offspring. Our findings suggest that developmental plasticity could generate dramatic differences in sexual competition between populations, and could contribute to reproductive isolation.
{"title":"Can developmental plasticity shape sexual competition and promote reproductive isolation?","authors":"Kristin Hubakk, Zachariah Wylde, Russell Bonduriansky","doi":"10.1093/beheco/arae047","DOIUrl":"https://doi.org/10.1093/beheco/arae047","url":null,"abstract":"\u0000 Environmental factors such as dietary nutrients can shape the expression of developmentally plastic sexual traits in many species. However, while there has been extensive research into the developmental plasticity of sexual traits at the individual level, the broader consequences of this variation at the population scale remain poorly understood. Here, we asked whether plastic responses to the developmental environment can shape sexual competition and initiate reproductive isolation between populations. We reared neriid flies, Telostylinus angusticollis, on nutrient-rich and nutrient-poor larval diets, generating adult flies that differed in body size and secondary sexual trait expression. We then investigated sexual competition in experimental populations from each developmental environment, and tested for reproductive isolation between flies from mismatched environments. We found that, compared with poor-diet populations, rich-diet populations exhibited more frequent and escalated male-male combat and more frequent mating and mate-guarding. However, we found no evidence that sexual selection was affected by the developmental environment. Mismatched female-male pairs tended to take longer to mate and rich-diet females often rejected poor-diet males, but mismatched pairs were not less likely to mate within 1 hour or produce viable offspring. Our findings suggest that developmental plasticity could generate dramatic differences in sexual competition between populations, and could contribute to reproductive isolation.","PeriodicalId":8840,"journal":{"name":"Behavioral Ecology","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141265425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Javier Abalos, G. Pérez i de Lanuza, Alicia Bartolomé, Océane Liehrmann, Fabien Aubret, Enrique Font
The interplay between morphological (structures) and behavioral (acts) signals in contest assessment is still poorly understood. During contests, males of the common wall lizard (Podarcis muralis) display both morphological (i.e. static color patches) and behavioral (i.e. raised-body display, foot shakes) traits. We set out to evaluate the role of these putative signals in determining the outcome and intensity of contests by recording agonistic behavior in ten mesocosm enclosures. We find that contests are typically won by males with relatively more black coloration, which are also more aggressive. However, black coloration does not seem to play a role in rival assessment, and behavioral traits are stronger predictors of contest outcome and winner aggression than prior experience, morphology, and coloration. Contest intensity is mainly driven by resource- and self-assessment, with males probably using behavioral threat (raised-body displays) and de-escalation signals (foot shakes) to communicate their willingness to engage/persist in a fight. Our results agree with the view that agonistic signals used during contests are not associated with mutual evaluation of developmentally-fixed attributes, and instead animals monitor each other to ensure that their motivation is matched by their rival. We emphasize the importance of testing the effect of signals on receiver behavior and discuss that social recognition in territorial species may select receivers to neglect potential morphological signals conveying static information on sex, age, or intrinsic quality.
{"title":"Behavioral threat and appeasement signals take precedence over static colors in lizard contests","authors":"Javier Abalos, G. Pérez i de Lanuza, Alicia Bartolomé, Océane Liehrmann, Fabien Aubret, Enrique Font","doi":"10.1093/beheco/arae045","DOIUrl":"https://doi.org/10.1093/beheco/arae045","url":null,"abstract":"\u0000 The interplay between morphological (structures) and behavioral (acts) signals in contest assessment is still poorly understood. During contests, males of the common wall lizard (Podarcis muralis) display both morphological (i.e. static color patches) and behavioral (i.e. raised-body display, foot shakes) traits. We set out to evaluate the role of these putative signals in determining the outcome and intensity of contests by recording agonistic behavior in ten mesocosm enclosures. We find that contests are typically won by males with relatively more black coloration, which are also more aggressive. However, black coloration does not seem to play a role in rival assessment, and behavioral traits are stronger predictors of contest outcome and winner aggression than prior experience, morphology, and coloration. Contest intensity is mainly driven by resource- and self-assessment, with males probably using behavioral threat (raised-body displays) and de-escalation signals (foot shakes) to communicate their willingness to engage/persist in a fight. Our results agree with the view that agonistic signals used during contests are not associated with mutual evaluation of developmentally-fixed attributes, and instead animals monitor each other to ensure that their motivation is matched by their rival. We emphasize the importance of testing the effect of signals on receiver behavior and discuss that social recognition in territorial species may select receivers to neglect potential morphological signals conveying static information on sex, age, or intrinsic quality.","PeriodicalId":8840,"journal":{"name":"Behavioral Ecology","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141265536","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Meng-Han Joseph Chung, Md Mahmud-Al-Hasan, Michael D Jennions, M. Head
Males often strategically adjust the number of available sperm based on the social context (i.e., sperm priming response), but it remains unclear how environmental and genetic factors shape this adjustment. In freshwater ecosystems, high ambient temperatures often lead to isolated pools of hotter water in which inbreeding occurs. Higher water temperatures and inbreeding can impair fish development, potentially disrupting sperm production. We used guppies (Poecilia reticulata) to investigate how developmental temperature (26 °C, 30 °C) and male inbreeding status (inbred, outbred) influence their sperm priming response. We also tested if sperm priming was affected by whether the female was a relative (sister), and whether she was inbred or outbred. There was no effect of rearing temperature; male inbreeding status alone determined the number of available sperm in response to female presence, her inbreeding status and her relatedness. Inbred males produced significantly more sperm in the presence of an unrelated, outbred female than when no female was present. Conversely, outbred males did not alter the number of sperm available in response to female presence or relatedness. Moreover, inbred males produced marginally more sperm when exposed to an unrelated female that was outbred rather than inbred, but there was no difference when exposed to an inbred female that was unrelated versus related. Together, a sperm priming response was only observed in inbred males when exposed to an outbred female. Outbred females in our study were larger than inbred females, suggesting that inbred males strategically allocated ejaculate resources towards females in better condition.
{"title":"Effects of inbreeding and elevated rearing temperatures on strategic sperm investment","authors":"Meng-Han Joseph Chung, Md Mahmud-Al-Hasan, Michael D Jennions, M. Head","doi":"10.1093/beheco/arae044","DOIUrl":"https://doi.org/10.1093/beheco/arae044","url":null,"abstract":"\u0000 Males often strategically adjust the number of available sperm based on the social context (i.e., sperm priming response), but it remains unclear how environmental and genetic factors shape this adjustment. In freshwater ecosystems, high ambient temperatures often lead to isolated pools of hotter water in which inbreeding occurs. Higher water temperatures and inbreeding can impair fish development, potentially disrupting sperm production. We used guppies (Poecilia reticulata) to investigate how developmental temperature (26 °C, 30 °C) and male inbreeding status (inbred, outbred) influence their sperm priming response. We also tested if sperm priming was affected by whether the female was a relative (sister), and whether she was inbred or outbred. There was no effect of rearing temperature; male inbreeding status alone determined the number of available sperm in response to female presence, her inbreeding status and her relatedness. Inbred males produced significantly more sperm in the presence of an unrelated, outbred female than when no female was present. Conversely, outbred males did not alter the number of sperm available in response to female presence or relatedness. Moreover, inbred males produced marginally more sperm when exposed to an unrelated female that was outbred rather than inbred, but there was no difference when exposed to an inbred female that was unrelated versus related. Together, a sperm priming response was only observed in inbred males when exposed to an outbred female. Outbred females in our study were larger than inbred females, suggesting that inbred males strategically allocated ejaculate resources towards females in better condition.","PeriodicalId":8840,"journal":{"name":"Behavioral Ecology","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141384272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Obligate brood parasites pass all their parental duties to foster parents of a host species. While best understood in birds and hymenopteran insects, obligate brood parasitism has evolved independently at least 59 times across many lineages. The ancestors of brood parasites often provided no parental care to their offspring. Instead, a trophic association with their eventual hosts commonly appears to precede the origin of a brood parasitic strategy. Here, we used a game theoretical model to explore the conditions under which brood parasitism can evolve from predation and be maintained in the population. Our model was inspired by the relationship between the cuckoo catfish (Synodontis multipunctatus) parasitising mouthbrooding cichlid fishes in the African Lake Tanganyika. Our model demonstrates the facilitatory role of host egg predation on the origin and evolutionary maintenance of brood parasitism through the exploitation of the host response to egg predation by brood parasites. We found no conditions under which brood parasitism as a pure strategy is evolutionarily stable, but we describe a range of evolutionarily stable equilibria when predators and parasites coexist. While our model is tailored to the cuckoo catfish, it generally applies to other systems where brood parasitism has evolved from other antagonistic behaviour.
{"title":"The evolution of brood parasitism from host egg predation","authors":"Pierick Mouginot, Matthias Galipaud, Marin Reichard","doi":"10.1093/beheco/arae043","DOIUrl":"https://doi.org/10.1093/beheco/arae043","url":null,"abstract":"\u0000 Obligate brood parasites pass all their parental duties to foster parents of a host species. While best understood in birds and hymenopteran insects, obligate brood parasitism has evolved independently at least 59 times across many lineages. The ancestors of brood parasites often provided no parental care to their offspring. Instead, a trophic association with their eventual hosts commonly appears to precede the origin of a brood parasitic strategy. Here, we used a game theoretical model to explore the conditions under which brood parasitism can evolve from predation and be maintained in the population. Our model was inspired by the relationship between the cuckoo catfish (Synodontis multipunctatus) parasitising mouthbrooding cichlid fishes in the African Lake Tanganyika. Our model demonstrates the facilitatory role of host egg predation on the origin and evolutionary maintenance of brood parasitism through the exploitation of the host response to egg predation by brood parasites. We found no conditions under which brood parasitism as a pure strategy is evolutionarily stable, but we describe a range of evolutionarily stable equilibria when predators and parasites coexist. While our model is tailored to the cuckoo catfish, it generally applies to other systems where brood parasitism has evolved from other antagonistic behaviour.","PeriodicalId":8840,"journal":{"name":"Behavioral Ecology","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141102870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-21eCollection Date: 2024-07-01DOI: 10.1093/beheco/arae040
Dagmar der Weduwen, Nick A R Jones, Adèle Dubosque, Stefan Schuster, Keith T Sillar, Mike Webster, Luke Rendell
Group living can lead to kleptoparasitism, the theft of resources by competitors. Under such conditions, foragers may alter their behavior to minimize competition. However, it is unclear how such behavioral changes impact foraging performance. Archerfish (Toxotes spp.) are a good model for investigating the behavioral responses to kleptoparasitism, as their hunting method (shooting waterjets at insects perched above the water) leaves them vulnerable to theft. They must hit the target prey with sufficient force to dislodge it; thus, the prey may land some distance away from the shooter. Kleptoparasitism rates increase with group size in archerfish, and individuals alter their behavior around conspecifics. We investigated whether group size affected shooting success, using 7-spot archerfish T. chatareus. We considered a fish's shot to be successful if it knocked a fly, placed on a transparent platform above the tank, into the water. The probability of shooting success was modeled as a function of group size, aiming duration, nearest neighbor distance and position, and trial number. We found no effect of group size, aiming duration, or nearest neighbor distance or position on shooting success. Shooting success increased as trials progressed, likely due to the fish becoming more familiar with the task. We also found no change in the kleptoparasitism rate between group sizes. Instead, the likelihood of the shooter consuming the prey depended on the types of competition present at the time of shooting. We suggest that archerfish shooting behavior can be influenced by the presence of conspecifics in ways not previously considered.
群居生活可能导致偷窃寄生,即竞争对手偷窃资源。在这种情况下,觅食者可能会改变行为,以尽量减少竞争。然而,目前还不清楚这种行为变化如何影响觅食表现。箭鱼(Toxotes spp.)是研究偷窃寄生行为反应的一个很好的模型,因为它们的狩猎方法(向栖息在水面上的昆虫喷射水柱)使它们很容易被偷窃。它们必须以足够的力量击中目标猎物才能使其脱落;因此,猎物可能会落到离射手有一段距离的地方。箭鱼的爬行寄生率随群体大小而增加,个体在同类周围的行为也会改变。我们使用 7 点箭鱼 T. chatareus 研究了群体大小是否会影响射杀成功率。如果一条鱼将放在鱼缸上方透明平台上的苍蝇击落水中,我们就认为它的射击成功了。射击成功的概率被模拟为群体大小、瞄准持续时间、最近邻距离和位置以及试验次数的函数。我们发现,群体大小、瞄准持续时间、近邻距离或位置对射击成功率没有影响。随着试验次数的增加,射击成功率也在增加,这可能是由于鱼对任务越来越熟悉。我们还发现,不同大小的群体之间的偷食率也没有变化。相反,射手吃掉猎物的可能性取决于射箭时的竞争类型。我们认为,箭鱼的射击行为会受到同种鱼的影响,而这种影响是以前从未考虑过的。
{"title":"Archerfish foraging success varies with immediate competition level but not group size.","authors":"Dagmar der Weduwen, Nick A R Jones, Adèle Dubosque, Stefan Schuster, Keith T Sillar, Mike Webster, Luke Rendell","doi":"10.1093/beheco/arae040","DOIUrl":"10.1093/beheco/arae040","url":null,"abstract":"<p><p>Group living can lead to kleptoparasitism, the theft of resources by competitors. Under such conditions, foragers may alter their behavior to minimize competition. However, it is unclear how such behavioral changes impact foraging performance. Archerfish (<i>Toxotes</i> spp.) are a good model for investigating the behavioral responses to kleptoparasitism, as their hunting method (shooting waterjets at insects perched above the water) leaves them vulnerable to theft. They must hit the target prey with sufficient force to dislodge it; thus, the prey may land some distance away from the shooter. Kleptoparasitism rates increase with group size in archerfish, and individuals alter their behavior around conspecifics. We investigated whether group size affected shooting success, using 7-spot archerfish <i>T. chatareus</i>. We considered a fish's shot to be successful if it knocked a fly, placed on a transparent platform above the tank, into the water. The probability of shooting success was modeled as a function of group size, aiming duration, nearest neighbor distance and position, and trial number. We found no effect of group size, aiming duration, or nearest neighbor distance or position on shooting success. Shooting success increased as trials progressed, likely due to the fish becoming more familiar with the task. We also found no change in the kleptoparasitism rate between group sizes. Instead, the likelihood of the shooter consuming the prey depended on the types of competition present at the time of shooting. We suggest that archerfish shooting behavior can be influenced by the presence of conspecifics in ways not previously considered.</p>","PeriodicalId":8840,"journal":{"name":"Behavioral Ecology","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11134209/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141174052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Elizabeth M George, Abigail M Weber, Kimberly A Rosvall
In seasonally breeding animals, costs and benefits of territorial aggression should vary over time; however, little work thus far has directly examined the scope and adaptive value of individual-level plasticity in aggression across breeding stages. We explore these issues using the tree swallow (Tachycineta bicolor), a single-brooded bird species in which females compete for limited nesting sites. We measured aggressiveness in nearly 100 females within three different stages: (1) shortly after territory-establishment, (2) during incubation, and (3) while caring for young chicks. Based on the timing, direction, and magnitude of behavioral changes between stages, we used k-means clustering to categorize each female’s behavior into a ‘plasticity type’. We then tested whether plasticity type and stage-specific aggression varied with key performance metrics. About 40% of females decreased aggressiveness across consecutive breeding stages to some degree, consistent with population-level patterns. 33% of females exhibited comparatively little plasticity, with moderate to low levels of aggression in all stages. Finally, 27% of females displayed steep decreases and then increases in aggression between stages; females exhibiting this pattern had significantly lower body mass while parenting, they tended to hatch fewer eggs, and they had the lowest observed overwinter survival rates. Other patterns of among-stage changes in aggressiveness were not associated with performance. These results reveal substantial among-individual variation in behavioral plasticity, which may reflect diverse solutions to trade-offs between current reproduction and future survival.
{"title":"Scope and adaptive value of modulating aggression over breeding stages in a competitive female bird","authors":"Elizabeth M George, Abigail M Weber, Kimberly A Rosvall","doi":"10.1093/beheco/arae042","DOIUrl":"https://doi.org/10.1093/beheco/arae042","url":null,"abstract":"In seasonally breeding animals, costs and benefits of territorial aggression should vary over time; however, little work thus far has directly examined the scope and adaptive value of individual-level plasticity in aggression across breeding stages. We explore these issues using the tree swallow (Tachycineta bicolor), a single-brooded bird species in which females compete for limited nesting sites. We measured aggressiveness in nearly 100 females within three different stages: (1) shortly after territory-establishment, (2) during incubation, and (3) while caring for young chicks. Based on the timing, direction, and magnitude of behavioral changes between stages, we used k-means clustering to categorize each female’s behavior into a ‘plasticity type’. We then tested whether plasticity type and stage-specific aggression varied with key performance metrics. About 40% of females decreased aggressiveness across consecutive breeding stages to some degree, consistent with population-level patterns. 33% of females exhibited comparatively little plasticity, with moderate to low levels of aggression in all stages. Finally, 27% of females displayed steep decreases and then increases in aggression between stages; females exhibiting this pattern had significantly lower body mass while parenting, they tended to hatch fewer eggs, and they had the lowest observed overwinter survival rates. Other patterns of among-stage changes in aggressiveness were not associated with performance. These results reveal substantial among-individual variation in behavioral plasticity, which may reflect diverse solutions to trade-offs between current reproduction and future survival.","PeriodicalId":8840,"journal":{"name":"Behavioral Ecology","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141152580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hee-Jin Noh, Linda Neaves, Alicia Grealy, N. Langmore
In theory, emancipation from parental care is expected to favour promiscuous mating systems. However, in avian brood parasites monogamy is surprisingly widespread and it has been proposed that this may be favoured by factors such as low population density and territoriality. Correspondingly, our previous research revealed that brood parasitic Horsfield’s bronze-cuckoos (Chalcites basalis), which occur at low population densities and defend territories, are monogamous. Here, we contrast this study with the mating system of the congeneric little bronze-cuckoo (C. minutillus), an obligate brood parasite that exploits more concentrated hosts and is therefore likely to occur at higher population densities. We use single nucleotide polymorphisms to characterise the reproductive patterns of unsampled adults by inferring sibling relationships among 30 offspring. We show that 1) little bronze-cuckoos occurred at high densities, 2) polygamy was the most common mating pattern found in this study in both sexes, and 3) where multiple cuckoo eggs are laid in the same nest, they were unrelated. These results indicate that females do not defend exclusive territories and males do not defend multiple females (polygyny). Instead, little bronze-cuckoos appear to have a non-territorial, promiscuous mating system. Our results are consistent with theoretical predictions that polygamy is more likely to evolve in species that are emancipated from parental care, where there are plenty of available mates and where home ranges are not defended.
{"title":"Molecular sibship reconstruction reveals a promiscuous mating system in brood parasitic little bronze-cuckoos (Chalcites minutillus)","authors":"Hee-Jin Noh, Linda Neaves, Alicia Grealy, N. Langmore","doi":"10.1093/beheco/arae041","DOIUrl":"https://doi.org/10.1093/beheco/arae041","url":null,"abstract":"\u0000 In theory, emancipation from parental care is expected to favour promiscuous mating systems. However, in avian brood parasites monogamy is surprisingly widespread and it has been proposed that this may be favoured by factors such as low population density and territoriality. Correspondingly, our previous research revealed that brood parasitic Horsfield’s bronze-cuckoos (Chalcites basalis), which occur at low population densities and defend territories, are monogamous. Here, we contrast this study with the mating system of the congeneric little bronze-cuckoo (C. minutillus), an obligate brood parasite that exploits more concentrated hosts and is therefore likely to occur at higher population densities. We use single nucleotide polymorphisms to characterise the reproductive patterns of unsampled adults by inferring sibling relationships among 30 offspring. We show that 1) little bronze-cuckoos occurred at high densities, 2) polygamy was the most common mating pattern found in this study in both sexes, and 3) where multiple cuckoo eggs are laid in the same nest, they were unrelated. These results indicate that females do not defend exclusive territories and males do not defend multiple females (polygyny). Instead, little bronze-cuckoos appear to have a non-territorial, promiscuous mating system. Our results are consistent with theoretical predictions that polygamy is more likely to evolve in species that are emancipated from parental care, where there are plenty of available mates and where home ranges are not defended.","PeriodicalId":8840,"journal":{"name":"Behavioral Ecology","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141121391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Melanin-based color polymorphism is predicted to evolve and maintain through differential fitness of morphs in different environments and several empirical studies indicate that life history strategies, physiology, and behavior vary among color morphs. Sex allocation theory predicts that parents should adjust their sex allocation based on differential costs of raising sons and daughters, and therefore color morphs are expected to modify their brood sex ratio decisions. In color polymorphic tawny owls (Strix aluco), the pheomelanistic brown morph is associated with higher energy requirements, faster growth, and higher parental effort than the gray morph. As hypothesized, we find that brown tawny owl mothers produced more daughters in early broods and more males in late broods, whereas gray mothers did the opposite. At fledging, daughters of early broods and of brown mothers were heavier than those of late broods or gray mothers. Hence, larger and more costly daughters appeared to benefit more than males from being born to brown mothers early in the season. Brown mothers breeding later in the season produced more cheap sons, while gray mothers face fewer challenges under limited resources and favor daughters. These findings suggest that environmental conditions influence brood sex allocation strategies of genetically determined color morphs differently.
{"title":"Sex allocation is color morph-specific and associated with fledging condition in a wild bird","authors":"Amandine Tooth, Chiara Morosinotto, Patrik Karell","doi":"10.1093/beheco/arae039","DOIUrl":"https://doi.org/10.1093/beheco/arae039","url":null,"abstract":"\u0000 Melanin-based color polymorphism is predicted to evolve and maintain through differential fitness of morphs in different environments and several empirical studies indicate that life history strategies, physiology, and behavior vary among color morphs. Sex allocation theory predicts that parents should adjust their sex allocation based on differential costs of raising sons and daughters, and therefore color morphs are expected to modify their brood sex ratio decisions. In color polymorphic tawny owls (Strix aluco), the pheomelanistic brown morph is associated with higher energy requirements, faster growth, and higher parental effort than the gray morph. As hypothesized, we find that brown tawny owl mothers produced more daughters in early broods and more males in late broods, whereas gray mothers did the opposite. At fledging, daughters of early broods and of brown mothers were heavier than those of late broods or gray mothers. Hence, larger and more costly daughters appeared to benefit more than males from being born to brown mothers early in the season. Brown mothers breeding later in the season produced more cheap sons, while gray mothers face fewer challenges under limited resources and favor daughters. These findings suggest that environmental conditions influence brood sex allocation strategies of genetically determined color morphs differently.","PeriodicalId":8840,"journal":{"name":"Behavioral Ecology","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140963737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chenke Zang, Meng-Han Joseph Chung, Teresa Neeman, Lauren Harrison, Ivan M Vinogradov, Michael D Jennions
Male-male contests for access to females or breeding resources is critical in determining male reproductive success. Larger males and those with more effective weaponry are more likely to win fights. However, even after controlling for such predictors of fighting ability, studies have reported a winner-loser effect: previous winners are more likely to win subsequent contests, while losers often suffer repeated defeats. While the effect of winning-losing is well-documented for the outcome of future fights, its effect on other behaviors (e.g., mating) remains poorly investigated. Here, we test whether a winning versus losing experience influenced subsequent behaviors of male mosquitofish (Gambusia holbrooki) towards rivals and potential mates. We housed focal males with either a smaller or larger opponent for 24 hours to manipulate their fighting experience to become winners or losers, respectively. The focal males then underwent tests that required them to enter and swim through a narrow corridor to reach females, bypassing a cylinder that contained either a larger rival male (competitive scenario), a juvenile or was empty (non-competitive scenarios). The tests were repeated after one week. Winners were more likely to leave the start area and to reach the females, but only when a larger rival was presented, indicating higher levels of risk-taking behavior in aggressive interactions. This winner-loser effect persisted for at least one week. We suggest that male mosquitofish adjust their assessment of their own and/or their rival’s fighting ability following contests in ways whose detection by researchers depends on the social context.
{"title":"Does losing reduce the tendency to engage with rivals to reach mates? An experimental test","authors":"Chenke Zang, Meng-Han Joseph Chung, Teresa Neeman, Lauren Harrison, Ivan M Vinogradov, Michael D Jennions","doi":"10.1093/beheco/arae037","DOIUrl":"https://doi.org/10.1093/beheco/arae037","url":null,"abstract":"Male-male contests for access to females or breeding resources is critical in determining male reproductive success. Larger males and those with more effective weaponry are more likely to win fights. However, even after controlling for such predictors of fighting ability, studies have reported a winner-loser effect: previous winners are more likely to win subsequent contests, while losers often suffer repeated defeats. While the effect of winning-losing is well-documented for the outcome of future fights, its effect on other behaviors (e.g., mating) remains poorly investigated. Here, we test whether a winning versus losing experience influenced subsequent behaviors of male mosquitofish (Gambusia holbrooki) towards rivals and potential mates. We housed focal males with either a smaller or larger opponent for 24 hours to manipulate their fighting experience to become winners or losers, respectively. The focal males then underwent tests that required them to enter and swim through a narrow corridor to reach females, bypassing a cylinder that contained either a larger rival male (competitive scenario), a juvenile or was empty (non-competitive scenarios). The tests were repeated after one week. Winners were more likely to leave the start area and to reach the females, but only when a larger rival was presented, indicating higher levels of risk-taking behavior in aggressive interactions. This winner-loser effect persisted for at least one week. We suggest that male mosquitofish adjust their assessment of their own and/or their rival’s fighting ability following contests in ways whose detection by researchers depends on the social context.","PeriodicalId":8840,"journal":{"name":"Behavioral Ecology","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140827724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Correction to: Dietary tryptophan affects group behavior in a social bird","authors":"","doi":"10.1093/beheco/arae038","DOIUrl":"https://doi.org/10.1093/beheco/arae038","url":null,"abstract":"","PeriodicalId":8840,"journal":{"name":"Behavioral Ecology","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141056713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}