Group spawning, polyandry reproductive behaviors, and multiple paternity are increasingly reported in anuran species. The Omei treefrog (Rhacophorus omeimontis), endemic to subtropical and mountainous forests of cen...Group spawning, polyandry reproductive behaviors, and multiple paternity are increasingly reported in anuran species. The Omei treefrog (Rhacophorus omeimontis), endemic to subtropical and mountainous forests of central and southwestern China, is a polyandrous lek-patterned breeder commonly showing multiple males-one female matings during the breeding season. To detect the traits of social and genetic polyandry in this species and explore the relationships between these traits, we investigated the breeding behaviors of a population of R. omeimontis in the Fengtongzhai National Nature Reserve, Baoxing County, Sichuan, China. We conducted paternity analyses using six microsatellite genetic markers. A total of 30 matings were recorded in the field (four monogamous pairs and 26 spawning groups). Our results revealed high proportions of social polyandry (86.7%) and multiple paternity (70.0%) and the numbers of joining males and genetic fathers among matings ranged from 1 to 8 and from 1 to 4, respectively. There was a significantly positive correlation between the intensities of social and genetic polyandry, indicating that multiple males-one female breeding behaviors could be an important promoter of multiple paternity. We considered the intense social polyandry and multiple paternity as consequences of intense male-male competition under a male-biased sex ratio and genetic benefits pursuing of the females. However, the proportion of genetic fathers in a spawning decreased with the increase of joining male number and most of their offspring belonged to a few males. This might be caused by a "making the best of a bad lot" reproductive strategy of the inferior male individuals.展开更多
Here we provide an example of simultaneous polyandry based on genetic evidence in Feirana kangxianensis. This stream-dwelling species occurs only in Kangxian County, southern Gansu Province, where it is sympatric with...Here we provide an example of simultaneous polyandry based on genetic evidence in Feirana kangxianensis. This stream-dwelling species occurs only in Kangxian County, southern Gansu Province, where it is sympatric with its sibling species E quadranus. During the breeding season the sex ratio of E kangxianensis was marginally female- biased (44~:59~) and the encounter rate in a relatively pristine habitat was significantly higher than that in heavily quarried habitats (9.6 ± 4.8 indiv./km vs. 3.2 ± 2.5 indiv./km). Three egg masses containing an average of 698 eggs were deposited on the underside of one or two adjacent flat rocks, 6.0-10.0 cm under the water surface and 1.0-3.5 cm above the streambed. Using Bayesian sibship clustering of nine polymorphic microsatellite genotypes, two females were detected as group-spawning in one oviposition site, with three males fertilizing each female's eggs simultaneously. We also discuss the conservation requirements of this range-restricted species and the evolutionary implication of its unusual reproductive strategy.展开更多
Within a honeybee population, due to polyandry, there are super-sister and half-sister relations, thus many sub-families exist. For the Chinese honeybee (Apis cerana cerana F.) a phylogenetic dendrogram has been const...Within a honeybee population, due to polyandry, there are super-sister and half-sister relations, thus many sub-families exist. For the Chinese honeybee (Apis cerana cerana F.) a phylogenetic dendrogram has been constructed in which 4 sub-families are clustered based on DNA fingerprint patterns. And it has been observed that each kind of workers is distributed to several different sub-families.展开更多
The third section of the book is the shortest of the three sections. While the other two are each over 100 pages long and feature an appendix, section three is only 40 pages long and has no appendix.
The crocodile lizard (Shinisaurus croeodilurus) is an ovoviviparoug lizard belonging to a monotypic family that originated during the end of the quaternary ice age. A rare species in the wild, the crocodile lizard w...The crocodile lizard (Shinisaurus croeodilurus) is an ovoviviparoug lizard belonging to a monotypic family that originated during the end of the quaternary ice age. A rare species in the wild, the crocodile lizard was listed in CITES Appendix II. Knowledge of the reproductive biology and mating system of this species is important for designing conservation strategies and improving genetic variation. To investigate the paternity of the crocodile lizards and to interpret their reproductive behaviour, we collected saliva from females, potential fathers and offspring in a semi- natural enclosure experiment and analyzed the paternity of the crocodile lizard using 12 microsatellite genetic loci. The overall observed incidence of multiple paternity was 42.9% (6 of 14 clutches) and Fis was 0.089 ± 0.056. These results indicate that the primary mating mode of the crocodile lizard is that males are polygynous while with females are polyandrous, and there is multiple paternity among offspring of the same mother.展开更多
The propensity of females to cross with more than one male is a relevant aspect in tephritid fruit fly biology since many species are pests of fruticulture.The knowledge about mating systems of a target pest-species i...The propensity of females to cross with more than one male is a relevant aspect in tephritid fruit fly biology since many species are pests of fruticulture.The knowledge about mating systems of a target pest-species is crucial for defining efficient strategies for insect population control,e.g.,for the sterile insect technique(SIT).The aim of this study was to evaluate the propensy to remate of the tephritid Anastrepha sp.1 aff.fraterculus females.For this purpose it was used an autosomic recessive mutation,rose,that affects eye-color,in two designed experimental systems:one in which wild-type and rose males were sequentially offered to cross with rose females and another one in which the rose females had to choose to cross with a wild-type,to a rose male or to both(remate).By simple analyses of the progeny phenotypes it was possible to recognize whether the females had remated or not.About a third of the females produced mixed progenies with wild-type and rose individuals,thereby indicating remating during the week the experiment lasted.Data indicated that remating rate was higher than previously reported for this species,and it could be shown that the sperms derived from the different males the females had crossed had been used in egg fertilization.展开更多
In polygynous systems,such as that exhibited by reindeer Rangifer tarandus,mate choice can be difficult to disentangle from male intrasexual competition because male behavior may constrain female choice.Multiple matin...In polygynous systems,such as that exhibited by reindeer Rangifer tarandus,mate choice can be difficult to disentangle from male intrasexual competition because male behavior may constrain female choice.Multiple mating may provide an avenue for female mate choice,though it is difficult to identify using behavioral estimators alone.Molecular techniques address this issue by affording ecologists an opportunity to reassess mating systems from a genetic perspective.We assessed the frequency and possible explanations for multiple mating in reindeer using a genetic approach to determine the success of observed copulations in a semi-domesticated herd in Kaamanen,Finland.Behavioral and genetic data were synthesized with population characteristics over a 7-year period to test the hypothesis that,if present,polyandry in reindeer is driven by sexual harassment from sub-dominant males.We observed multiple mating in 42%of females,with as many as 60%exhibiting multiple mating in certain years.We found no evidence that multiple mating resulted from sexual harassment by sub-dominant males,suggesting that it is likely a deliberate strategy among females.Conversion rate of copulations into paternities varied with male size,with smaller males more likely to experience mismatch than larger males.Female preference for larger males persisted despite the occurrence of multiple mating,possibly suggesting a mechanism for cryptic post-copulatory selection.We suggest further research to delineate the possible influence of cryptic post-copulatory selection and multiple mating to defend against infertility in exhausted males.展开更多
Males of the nursery web spider Pisaura mirabil usually offer an insect prey wrapped in white silk as a nuptial gift to facilitate copulation. Males exploit female foraging preferences in a sexual context as females f...Males of the nursery web spider Pisaura mirabil usually offer an insect prey wrapped in white silk as a nuptial gift to facilitate copulation. Males exploit female foraging preferences in a sexual context as females feed on the gift during copula- tion. It is possible for males to copulate without a gift, however strong female preference for the gift leads to dramatically higher mating success for gift-giving males. Females are polyandrous, and gift-giving males achieve higher mating success, longer copulations, and increased sperm transfer that confer advantages in sperm competition. Intriguingly, field studies show that ap- proximately one third of males carry a worthless gift consisting of dry and empty insect exoskeletons or plant fragments wrapped in white silk. Silk wrapping disguises gift content and females are able to disclose gift content only after accepting and feeding on the gift, meanwhile males succeed in transferring sperm. The evolution of deceit by worthless gift donation may be favoured by strong intra-sexual competition and costs of gift-construction including prey capture, lost foraging opportunities and investment in silk wrapping. Females that receive empty worthless gifts terminate copulation sooner, which reduces sperm transfer and likely disadvantages males in sperm competition. The gift-giving trait may thus become a target of sexually antagonistic co-evolution, where deceit by worthless gifts leads to female resistance to the trait. We discuss factors such as female mating rate and intensity of sperm competition that may shape the evolution of male deception, and how ecological factors may influence the evolution and maintenance of worthless gifts as an evolutionarily stable alternative mating strategy by frequency dependent selection展开更多
Seminal gifts range from important material donations to items that provide little direct benefit to females.Promiscuous,female silk corn flies Euxesta eluta expel and consume male ejaculates immediately after mating....Seminal gifts range from important material donations to items that provide little direct benefit to females.Promiscuous,female silk corn flies Euxesta eluta expel and consume male ejaculates immediately after mating.The evolution and function of this peculiar behavior are currently unknown.We performed a series of experiments aimed to:determine if females under different dietary regimes derive nutrients or water for survival and/or reproduction from ejaculate consumption,if males suffer a fitness cost from supplying females with ejaculates,and if females prefer to mate and/or are more likely to store sperm from well fed than nutritionally stressed presumably inferior males.Experiments revealed that protein deprived E.eluta females derive nutrients for ovarian development through consumption of ejaculates of protein fed males.No seminal products affecting survival appear to be transferred in the consumed ejaculate.However,ovarian development,in contrast to testes growth,occurs in detriment of longevity.Females preferred to mate with protein fed males,yet sperm retention in spermathecae was extremely rare after a single mating.This finding suggests that females could be exerting post copulatory control.A key question that remained to be addressed for the understanding of this puzzling and promiscuous mating system is what ecological factors or male traits drive females to retain sperm from one or several males in order to achieve and/or maximize fertilization potential.展开更多
Ecological variation in resources can in flue nee the distributi on and en counter rates of potential mates and competitors and, con sequently, the opport unity for sexual selection. Factors that influence the likelih...Ecological variation in resources can in flue nee the distributi on and en counter rates of potential mates and competitors and, con sequently, the opport unity for sexual selection. Factors that influence the likelihood that females mate multiply could also affect the potential for sperm competition. In Wellington tree weta (Hemideina crassidens, plural "weta"), the size of tree cavities (called galleries) used as refuges affects weta distribution and thus the opport unity for sexual selection and selection on male weaponry size. We examined the predicted effects of gallery size and male weap onry size on the potential for sperm competition. We asked if gallery size in flue need the potential for multiple mating by females and potential for sperm competition, if male weaponry size was associated with relative expected sperm competition intensity (SCI), and if estimated male mating success was correlated with pote ntial SCI. To qua ntify relative competitive envir on merits of males, we created and analyzed networks of potential competitors based on which males could have mated with the same females. We found that small galleries had higher potential for female multiple mating and higher potential for sperm competition. Size of male weaponry was not associated with expected relative SCI. Regardless of gallery size, males with more potential mates were expected to face lower expected relative sperm competition. Thus, in this system, variation in the size of available refuges is likely to in flue nee the pote ntial for sperm competiti on, in a way that we might expect to in crease variation in overall reproductive success.展开更多
Multiple mating by females,polyandry,is common in insects,including in tephritid fruit flies.Female insects that remate commonly store sperm of multiple males.How the sperm of different males contribute to paternity i...Multiple mating by females,polyandry,is common in insects,including in tephritid fruit flies.Female insects that remate commonly store sperm of multiple males.How the sperm of different males contribute to paternity is an important element of sexual selection.Sexual behavior and reproduction of the Queensland fruit fly(Qfly),Bactrocera tryoni,has been extensively investigated both in relation to understanding this economically important species’reproductive biology and in relation to implications for Sterile Insect Technique(SIT),whereby sterile flies are released to constrain reproduction of pest populations.Despite numerous studies of pre-and postcopulatory sexual selection in Qfly,there have been no direct studies of paternity patterns in polyandrous female Qflies.We used two morphologically distinguishable lines to investigate patterns of sperm use in Qfly.The two lines showed comparable mating performance evidenced by similar mating and remating frequency,copula duration,and proportion of second mate paternity(P2)between reciprocal crosses.The mechanism of sperm usage,with P2 close to 0.5 immediately after the second mating followed by gradual decrease of P2 as females aged,is most consistent with stratification or repositioning of sperm.Patterns observed in the present study are compared with the available information from other tephritid fruit flies,and are discussed in relation to this species’reproductive biology,known patterns of sperm storage,and SIT.展开更多
A growing body of empirical evidence shows that females of many animal species gain benefits by mating polyan- drously, and often prefer to mate with novel males over previous mates. Although a female preference for n...A growing body of empirical evidence shows that females of many animal species gain benefits by mating polyan- drously, and often prefer to mate with novel males over previous mates. Although a female preference for novel males has been ,demonstrated for multiple animal taxa, the mechanisms used by females to discriminate between novel and previous mates remain largely unknown. However, recent studies suggest that in decorated crickets Gryllodes sigillatus, females actually imbue males with their own chemical cues, known as cuticular hydrocarbons (CHCs) during mating, and utilize chemosensory self-referencing 1:o recognize recent mates. Here we review evidence that self-referent phenotype matching is a widespread mechanism of recogni- tion in arthropods, and explore how CHCs are used to facilitate mate-choice decisions. There is substantial evidence that CHCs are used as recognition cues to discriminate between species, kin, sexes, mates, individuals, and self and non-self, and are used to facilitate mate-choice decisions in a wide range of arthropod taxa. There is also evidence that CHCs are often transferred between individuals during direct physical contact, including copulation. Chemosensory self-referencing via cuticular hydrocarbons could provide a simple, but reliable mechanism for identifying individuals from previous mating encounters. This mechanism does not require any specialized cognitive abilities because an individual's phenotype is always available for reference. Given the ubiqui- tous use of CHCs among arthropods, chemosensory self-referencing may be a widespread mechanism used by female arthropods to facilitate ibmale mate-choice decisions and to enhance opportunities for polyandry [Current Zoology 59 (2): 239-248, 2013].展开更多
Males can control female reproduction using genital plugs to impede access by rivals.In social bees,ants,and wasps,plugging may involve traumatic mating,with females being harmed.In stingless bees,chances are that plu...Males can control female reproduction using genital plugs to impede access by rivals.In social bees,ants,and wasps,plugging may involve traumatic mating,with females being harmed.In stingless bees,chances are that plugs may promote ovarian activan,and are thought to ensure single mating—a general tendency among the social Hymenoptera.However,understanding on relationships between mating plugs,traumatic mating,and mating systems in stingless bees remains limited.To address this,we(1)compared mated queens of 7 Neotropical species to understand the patterns of copulatory marks in females and(2)compared pre-and post-mating genitalia of males and females in Melipona fasciculata to depict plug functional morphology.Data revealed an unprecedented consequence of mating in stingless bees:the characteristic marks left by mating plugs on female abdomens and the inferences that can be made from them.To our surprise,in 1 species M.fasciculata we found that queens retain the plug long after mating,and may carry it for the rest of their lives.All the other 6 species retained the plug for only a short period.Remated queens were only found in M.seminigra,whose multiple copulatory marks match previous findings of polyandry in this species.Our study shows that queens can remate,and suggests that male genital morphology may determine in part the time persistence of plugs.We conclude that traumatic mating plugs do not fully prevent remating in stingless bees and that mating systems are not uniform in this group.Nonetheless,exceptional cases of facultative polyandry in social insects—for example,when mating plugs fail—may confirm a general tendency for single mating in close link with efficient mating plugs.展开更多
基金supported by the National Natural Science Foundation of China(No.31470442)
文摘Group spawning, polyandry reproductive behaviors, and multiple paternity are increasingly reported in anuran species. The Omei treefrog (Rhacophorus omeimontis), endemic to subtropical and mountainous forests of central and southwestern China, is a polyandrous lek-patterned breeder commonly showing multiple males-one female matings during the breeding season. To detect the traits of social and genetic polyandry in this species and explore the relationships between these traits, we investigated the breeding behaviors of a population of R. omeimontis in the Fengtongzhai National Nature Reserve, Baoxing County, Sichuan, China. We conducted paternity analyses using six microsatellite genetic markers. A total of 30 matings were recorded in the field (four monogamous pairs and 26 spawning groups). Our results revealed high proportions of social polyandry (86.7%) and multiple paternity (70.0%) and the numbers of joining males and genetic fathers among matings ranged from 1 to 8 and from 1 to 4, respectively. There was a significantly positive correlation between the intensities of social and genetic polyandry, indicating that multiple males-one female breeding behaviors could be an important promoter of multiple paternity. We considered the intense social polyandry and multiple paternity as consequences of intense male-male competition under a male-biased sex ratio and genetic benefits pursuing of the females. However, the proportion of genetic fathers in a spawning decreased with the increase of joining male number and most of their offspring belonged to a few males. This might be caused by a "making the best of a bad lot" reproductive strategy of the inferior male individuals.
基金supported by the National Natural Science Foundation of China (31471964, 31200411)the Chinese Academy of Sciences (Y3C3011100)
文摘Here we provide an example of simultaneous polyandry based on genetic evidence in Feirana kangxianensis. This stream-dwelling species occurs only in Kangxian County, southern Gansu Province, where it is sympatric with its sibling species E quadranus. During the breeding season the sex ratio of E kangxianensis was marginally female- biased (44~:59~) and the encounter rate in a relatively pristine habitat was significantly higher than that in heavily quarried habitats (9.6 ± 4.8 indiv./km vs. 3.2 ± 2.5 indiv./km). Three egg masses containing an average of 698 eggs were deposited on the underside of one or two adjacent flat rocks, 6.0-10.0 cm under the water surface and 1.0-3.5 cm above the streambed. Using Bayesian sibship clustering of nine polymorphic microsatellite genotypes, two females were detected as group-spawning in one oviposition site, with three males fertilizing each female's eggs simultaneously. We also discuss the conservation requirements of this range-restricted species and the evolutionary implication of its unusual reproductive strategy.
文摘Within a honeybee population, due to polyandry, there are super-sister and half-sister relations, thus many sub-families exist. For the Chinese honeybee (Apis cerana cerana F.) a phylogenetic dendrogram has been constructed in which 4 sub-families are clustered based on DNA fingerprint patterns. And it has been observed that each kind of workers is distributed to several different sub-families.
文摘The third section of the book is the shortest of the three sections. While the other two are each over 100 pages long and feature an appendix, section three is only 40 pages long and has no appendix.
基金supported by the National Natural Science Foundation of China(No.31360522)
文摘The crocodile lizard (Shinisaurus croeodilurus) is an ovoviviparoug lizard belonging to a monotypic family that originated during the end of the quaternary ice age. A rare species in the wild, the crocodile lizard was listed in CITES Appendix II. Knowledge of the reproductive biology and mating system of this species is important for designing conservation strategies and improving genetic variation. To investigate the paternity of the crocodile lizards and to interpret their reproductive behaviour, we collected saliva from females, potential fathers and offspring in a semi- natural enclosure experiment and analyzed the paternity of the crocodile lizard using 12 microsatellite genetic loci. The overall observed incidence of multiple paternity was 42.9% (6 of 14 clutches) and Fis was 0.089 ± 0.056. These results indicate that the primary mating mode of the crocodile lizard is that males are polygynous while with females are polyandrous, and there is multiple paternity among offspring of the same mother.
文摘The propensity of females to cross with more than one male is a relevant aspect in tephritid fruit fly biology since many species are pests of fruticulture.The knowledge about mating systems of a target pest-species is crucial for defining efficient strategies for insect population control,e.g.,for the sterile insect technique(SIT).The aim of this study was to evaluate the propensy to remate of the tephritid Anastrepha sp.1 aff.fraterculus females.For this purpose it was used an autosomic recessive mutation,rose,that affects eye-color,in two designed experimental systems:one in which wild-type and rose males were sequentially offered to cross with rose females and another one in which the rose females had to choose to cross with a wild-type,to a rose male or to both(remate).By simple analyses of the progeny phenotypes it was possible to recognize whether the females had remated or not.About a third of the females produced mixed progenies with wild-type and rose individuals,thereby indicating remating during the week the experiment lasted.Data indicated that remating rate was higher than previously reported for this species,and it could be shown that the sperms derived from the different males the females had crossed had been used in egg fertilization.
基金We thank the following organizations for their financial support:the Québec Centre for Biodiversity Science(QCBS)and the Northern Scientific Training Program(NSTP)to K.Coombs,the Natural Sciences and Engineering Research Council of Canada(NSERCgrant number 303807)to R.Weladji,and NORDFORSK(project number 76915)to O.Holand and K.Rod.
文摘In polygynous systems,such as that exhibited by reindeer Rangifer tarandus,mate choice can be difficult to disentangle from male intrasexual competition because male behavior may constrain female choice.Multiple mating may provide an avenue for female mate choice,though it is difficult to identify using behavioral estimators alone.Molecular techniques address this issue by affording ecologists an opportunity to reassess mating systems from a genetic perspective.We assessed the frequency and possible explanations for multiple mating in reindeer using a genetic approach to determine the success of observed copulations in a semi-domesticated herd in Kaamanen,Finland.Behavioral and genetic data were synthesized with population characteristics over a 7-year period to test the hypothesis that,if present,polyandry in reindeer is driven by sexual harassment from sub-dominant males.We observed multiple mating in 42%of females,with as many as 60%exhibiting multiple mating in certain years.We found no evidence that multiple mating resulted from sexual harassment by sub-dominant males,suggesting that it is likely a deliberate strategy among females.Conversion rate of copulations into paternities varied with male size,with smaller males more likely to experience mismatch than larger males.Female preference for larger males persisted despite the occurrence of multiple mating,possibly suggesting a mechanism for cryptic post-copulatory selection.We suggest further research to delineate the possible influence of cryptic post-copulatory selection and multiple mating to defend against infertility in exhausted males.
文摘Males of the nursery web spider Pisaura mirabil usually offer an insect prey wrapped in white silk as a nuptial gift to facilitate copulation. Males exploit female foraging preferences in a sexual context as females feed on the gift during copula- tion. It is possible for males to copulate without a gift, however strong female preference for the gift leads to dramatically higher mating success for gift-giving males. Females are polyandrous, and gift-giving males achieve higher mating success, longer copulations, and increased sperm transfer that confer advantages in sperm competition. Intriguingly, field studies show that ap- proximately one third of males carry a worthless gift consisting of dry and empty insect exoskeletons or plant fragments wrapped in white silk. Silk wrapping disguises gift content and females are able to disclose gift content only after accepting and feeding on the gift, meanwhile males succeed in transferring sperm. The evolution of deceit by worthless gift donation may be favoured by strong intra-sexual competition and costs of gift-construction including prey capture, lost foraging opportunities and investment in silk wrapping. Females that receive empty worthless gifts terminate copulation sooner, which reduces sperm transfer and likely disadvantages males in sperm competition. The gift-giving trait may thus become a target of sexually antagonistic co-evolution, where deceit by worthless gifts leads to female resistance to the trait. We discuss factors such as female mating rate and intensity of sperm competition that may shape the evolution of male deception, and how ecological factors may influence the evolution and maintenance of worthless gifts as an evolutionarily stable alternative mating strategy by frequency dependent selection
基金This experiments where funded with PICT 2015 N°0191 awarded to SA.
文摘Seminal gifts range from important material donations to items that provide little direct benefit to females.Promiscuous,female silk corn flies Euxesta eluta expel and consume male ejaculates immediately after mating.The evolution and function of this peculiar behavior are currently unknown.We performed a series of experiments aimed to:determine if females under different dietary regimes derive nutrients or water for survival and/or reproduction from ejaculate consumption,if males suffer a fitness cost from supplying females with ejaculates,and if females prefer to mate and/or are more likely to store sperm from well fed than nutritionally stressed presumably inferior males.Experiments revealed that protein deprived E.eluta females derive nutrients for ovarian development through consumption of ejaculates of protein fed males.No seminal products affecting survival appear to be transferred in the consumed ejaculate.However,ovarian development,in contrast to testes growth,occurs in detriment of longevity.Females preferred to mate with protein fed males,yet sperm retention in spermathecae was extremely rare after a single mating.This finding suggests that females could be exerting post copulatory control.A key question that remained to be addressed for the understanding of this puzzling and promiscuous mating system is what ecological factors or male traits drive females to retain sperm from one or several males in order to achieve and/or maximize fertilization potential.
文摘Ecological variation in resources can in flue nee the distributi on and en counter rates of potential mates and competitors and, con sequently, the opport unity for sexual selection. Factors that influence the likelihood that females mate multiply could also affect the potential for sperm competition. In Wellington tree weta (Hemideina crassidens, plural "weta"), the size of tree cavities (called galleries) used as refuges affects weta distribution and thus the opport unity for sexual selection and selection on male weaponry size. We examined the predicted effects of gallery size and male weap onry size on the potential for sperm competition. We asked if gallery size in flue need the potential for multiple mating by females and potential for sperm competition, if male weaponry size was associated with relative expected sperm competition intensity (SCI), and if estimated male mating success was correlated with pote ntial SCI. To qua ntify relative competitive envir on merits of males, we created and analyzed networks of potential competitors based on which males could have mated with the same females. We found that small galleries had higher potential for female multiple mating and higher potential for sperm competition. Size of male weaponry was not associated with expected relative SCI. Regardless of gallery size, males with more potential mates were expected to face lower expected relative sperm competition. Thus, in this system, variation in the size of available refuges is likely to in flue nee the pote ntial for sperm competiti on, in a way that we might expect to in crease variation in overall reproductive success.
基金The authors thank Dr.Simon Baxter from the University of Melbourne(previously University of Adelaide)for facilitating the use of yellowr line Qfly colony.This research was conducted as part of the SITplus collaborative fruit fly program.Projeet Raising Q-ly Sterile Inseet Tech-nique to World Standard(HG14033)is funded by the Hort Frontiers Fruit Fly Fund,part of the Hort Frontiers strategic partnership initiative developed by Hort Innovation,with co-investment from Macquarie University and contributions from the Australian Government.JS was supported by a Macquarie University iRTP Scholarship.
文摘Multiple mating by females,polyandry,is common in insects,including in tephritid fruit flies.Female insects that remate commonly store sperm of multiple males.How the sperm of different males contribute to paternity is an important element of sexual selection.Sexual behavior and reproduction of the Queensland fruit fly(Qfly),Bactrocera tryoni,has been extensively investigated both in relation to understanding this economically important species’reproductive biology and in relation to implications for Sterile Insect Technique(SIT),whereby sterile flies are released to constrain reproduction of pest populations.Despite numerous studies of pre-and postcopulatory sexual selection in Qfly,there have been no direct studies of paternity patterns in polyandrous female Qflies.We used two morphologically distinguishable lines to investigate patterns of sperm use in Qfly.The two lines showed comparable mating performance evidenced by similar mating and remating frequency,copula duration,and proportion of second mate paternity(P2)between reciprocal crosses.The mechanism of sperm usage,with P2 close to 0.5 immediately after the second mating followed by gradual decrease of P2 as females aged,is most consistent with stratification or repositioning of sperm.Patterns observed in the present study are compared with the available information from other tephritid fruit flies,and are discussed in relation to this species’reproductive biology,known patterns of sperm storage,and SIT.
基金Acknowledgements This work was supported by grants from the National Science Foundation and a visiting profes- sorship from The Leverhulme Trust to S.K.S., a University Royal Society Fellowship and Royal Society Equipment Grant to J.H, and grants from the Orthopterists' Society, the Beta Lambda Chapter of Phi Sigma, and the Graduate Student As- sociation of Illinois State University to C.B.W. We thank Gil Rosenthal, and two anonymous reviewers for constructive comments on the manuscript.
文摘A growing body of empirical evidence shows that females of many animal species gain benefits by mating polyan- drously, and often prefer to mate with novel males over previous mates. Although a female preference for novel males has been ,demonstrated for multiple animal taxa, the mechanisms used by females to discriminate between novel and previous mates remain largely unknown. However, recent studies suggest that in decorated crickets Gryllodes sigillatus, females actually imbue males with their own chemical cues, known as cuticular hydrocarbons (CHCs) during mating, and utilize chemosensory self-referencing 1:o recognize recent mates. Here we review evidence that self-referent phenotype matching is a widespread mechanism of recogni- tion in arthropods, and explore how CHCs are used to facilitate mate-choice decisions. There is substantial evidence that CHCs are used as recognition cues to discriminate between species, kin, sexes, mates, individuals, and self and non-self, and are used to facilitate mate-choice decisions in a wide range of arthropod taxa. There is also evidence that CHCs are often transferred between individuals during direct physical contact, including copulation. Chemosensory self-referencing via cuticular hydrocarbons could provide a simple, but reliable mechanism for identifying individuals from previous mating encounters. This mechanism does not require any specialized cognitive abilities because an individual's phenotype is always available for reference. Given the ubiqui- tous use of CHCs among arthropods, chemosensory self-referencing may be a widespread mechanism used by female arthropods to facilitate ibmale mate-choice decisions and to enhance opportunities for polyandry [Current Zoology 59 (2): 239-248, 2013].
基金This research was funded by Coordenac¸~ao de Aperfeic¸oamento de Pessoal de Nı´vel Superior-CAPES/Empresa Brasileira de Pesquisa Agropecua´ria-EMBRAPA(15/2014)who provided grants to J.C.V.,and by Conselho Nacional de Desenvolvimento Cientı´fico e Tecnologico-CNPq(400435/2014-4)through the PVE 2014 Project.
文摘Males can control female reproduction using genital plugs to impede access by rivals.In social bees,ants,and wasps,plugging may involve traumatic mating,with females being harmed.In stingless bees,chances are that plugs may promote ovarian activan,and are thought to ensure single mating—a general tendency among the social Hymenoptera.However,understanding on relationships between mating plugs,traumatic mating,and mating systems in stingless bees remains limited.To address this,we(1)compared mated queens of 7 Neotropical species to understand the patterns of copulatory marks in females and(2)compared pre-and post-mating genitalia of males and females in Melipona fasciculata to depict plug functional morphology.Data revealed an unprecedented consequence of mating in stingless bees:the characteristic marks left by mating plugs on female abdomens and the inferences that can be made from them.To our surprise,in 1 species M.fasciculata we found that queens retain the plug long after mating,and may carry it for the rest of their lives.All the other 6 species retained the plug for only a short period.Remated queens were only found in M.seminigra,whose multiple copulatory marks match previous findings of polyandry in this species.Our study shows that queens can remate,and suggests that male genital morphology may determine in part the time persistence of plugs.We conclude that traumatic mating plugs do not fully prevent remating in stingless bees and that mating systems are not uniform in this group.Nonetheless,exceptional cases of facultative polyandry in social insects—for example,when mating plugs fail—may confirm a general tendency for single mating in close link with efficient mating plugs.