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Selection on Sperm Count, but Not on Sperm Morphology or Velocity, in a Wild Population of Anolis Lizards. Cells 2021; 10:cells10092369. [PMID: 34572018 PMCID: PMC8464841 DOI: 10.3390/cells10092369] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 09/04/2021] [Accepted: 09/06/2021] [Indexed: 12/25/2022] Open
Abstract
Sperm competition is a widespread phenomenon that shapes male reproductive success. Ejaculates present many potential targets for postcopulatory selection (e.g., sperm morphology, count, and velocity), which are often highly correlated and potentially subject to complex multivariate selection. Although multivariate selection on ejaculate traits has been observed in laboratory experiments, it is unclear whether selection is similarly complex in wild populations, where individuals mate frequently over longer periods of time. We measured univariate and multivariate selection on sperm morphology, sperm count, and sperm velocity in a wild population of brown anole lizards (Anolis sagrei). We conducted a mark-recapture study with genetic parentage assignment to estimate individual reproductive success. We found significant negative directional selection and negative quadratic selection on sperm count, but we did not detect directional or quadratic selection on any other sperm traits, nor did we detect correlational selection on any trait combinations. Our results may reflect pressure on males to produce many small ejaculates and mate frequently over a six-month reproductive season. This study is the first to measure multivariate selection on sperm traits in a wild population and provides an interesting contrast to experimental studies of external fertilizers, which have found complex multivariate selection on sperm phenotypes.
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2
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Locatello L, Borgheresi O, Poli F, Pilastro A, Rasotto MB. Black goby territorial males adjust their ejaculate's characteristics in response to the presence of sneakers. Biol Lett 2021; 17:20210201. [PMID: 34343439 DOI: 10.1098/rsbl.2021.0201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In many species, males can rapidly adjust their ejaculate performance in response to changing levels of sperm competition, an ability that is probably mediated by seminal fluid adaptive plasticity. In the black goby, Gobius niger, territorial males attach viscous ejaculate trails to the nest roof, from which sperm are slowly released into the water during the long-lasting spawning events. Sneaker males release their sperm in the vicinity of the nest, and territorial males try to keep them at a distance by patrolling their territory. We show here that territorial males' ejaculate trails released a higher proportion of their sperm in the presence of a single sneaker, but this proportion decreased when there were three sneakers, an effect that is most likely mediated by a change in the seminal fluid composition. Field observations showed that when multiple sneaking attempts occurred, territorial males spent more time outside the nest, suggesting that ejaculation rate and territory defence are traded-off. Altogether, these results suggest that the adjustment of sperm release from the ejaculate may be strategic, guaranteeing a more continuous concentration of the territorial male's sperm in the nest, although at a lower level, when he is engaged in prolonged territory defence outside the nest.
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Affiliation(s)
- Lisa Locatello
- Department of Biology, University of Padova, Via Ugo Bassi 58/b, 35121 Padova, Italy.,Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Fano Marine Centre, Viale Adriatico 1/N, 61032 Fano, Italy
| | - Oliviero Borgheresi
- Department of Biology, University of Padova, Via Ugo Bassi 58/b, 35121 Padova, Italy
| | - Federica Poli
- Department of Biology, University of Padova, Via Ugo Bassi 58/b, 35121 Padova, Italy
| | - Andrea Pilastro
- Department of Biology, University of Padova, Via Ugo Bassi 58/b, 35121 Padova, Italy
| | - Maria B Rasotto
- Department of Biology, University of Padova, Via Ugo Bassi 58/b, 35121 Padova, Italy
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3
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Poli F, Marino IAM, Santon M, Bozzetta E, Pellizzato G, Zane L, Rasotto MB. Spatial asymmetry of the paternity success in nests of a fish with alternative reproductive tactics. Sci Rep 2021; 11:3091. [PMID: 33542278 PMCID: PMC7862370 DOI: 10.1038/s41598-021-82508-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 01/20/2021] [Indexed: 11/16/2022] Open
Abstract
Guard-sneaker tactics are widespread among fish, where territorial males defend a nest and provide parental care while sneakers try to steal fertilizations. Territorials and sneakers adopt diverse pre- and post-mating strategies, adjusting their ejaculate investment and/or behavioural responses to the presence of competitors. The relative distance of competitors from the spawning female plays a major role in influencing male mating strategies and the resulting paternity share. However, territorial male quality and sneaking intensity do not fully account for the variability in the relative siring success occurring among species. An often neglected factor potentially affecting sneakers proximity to females is the nest structure. We conducted a field experiment using the black goby, whose nests show two openings of different size. We found that territorial males defend more and sneaking pressure is higher at the front, larger access of the nest than at the back, smaller one. Moreover, microsatellite paternity analysis shows that territorials sire more offspring at the back of their nest. Such a predictable spatial distribution of the paternity share suggests that nest structure might work as an indirect cue of male relative siring success, potentially influencing the territorial male investment in parental care and/or the female egg deposition strategy.
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Affiliation(s)
- F Poli
- Department of Biology, University of Padova, Via U. Bassi 58/B, 35131, Padua, Italy.
| | - I A M Marino
- Department of Biology, University of Padova, Via U. Bassi 58/B, 35131, Padua, Italy
- Consorzio Interuniversitario per le Scienze del Mare (CoNISMa), Piazzale Flaminio 9, 00196, Rome, Italy
| | - M Santon
- Institute for Evolution and Ecology, Department of Biology, University of Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany
| | - E Bozzetta
- Department of Biology, University of Padova, Via U. Bassi 58/B, 35131, Padua, Italy
| | - G Pellizzato
- Department of Biology, University of Padova, Via U. Bassi 58/B, 35131, Padua, Italy
| | - L Zane
- Department of Biology, University of Padova, Via U. Bassi 58/B, 35131, Padua, Italy
- Consorzio Interuniversitario per le Scienze del Mare (CoNISMa), Piazzale Flaminio 9, 00196, Rome, Italy
| | - M B Rasotto
- Department of Biology, University of Padova, Via U. Bassi 58/B, 35131, Padua, Italy
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4
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Churchill ER, Bridle JR, Thom MD. Spatially clustered resources increase male aggregation and mating duration in Drosophila melanogaster. Anim Behav 2020. [DOI: 10.1016/j.anbehav.2020.09.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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5
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Picchi L, Lorenzi MC. Gender-related behaviors: evidence for a trade-off between sexual functions in a hermaphrodite. Behav Ecol 2019. [DOI: 10.1093/beheco/arz014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Laura Picchi
- LEEC—Laboratoire d’Ethologie Expérimentale et Comparée, Université Paris 13, Sorbonne Paris Cité, J.-B. Clément, Villetaneuse, France
| | - Maria Cristina Lorenzi
- LEEC—Laboratoire d’Ethologie Expérimentale et Comparée, Université Paris 13, Sorbonne Paris Cité, J.-B. Clément, Villetaneuse, France
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6
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Alpern JHM, Asselin MM, Moehring AJ. Identification of a novel sperm class and its role in fertilization in Drosophila. J Evol Biol 2018; 32:259-266. [DOI: 10.1111/jeb.13409] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Revised: 11/21/2018] [Accepted: 11/22/2018] [Indexed: 11/30/2022]
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7
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Santi M, Picchi L, Lorenzi MC. Dynamic modulation of reproductive strategies in a simultaneous hermaphrodite and preference for the male role. Anim Behav 2018. [DOI: 10.1016/j.anbehav.2018.10.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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8
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Firman RC, Garcia‐Gonzalez F, Simmons LW, André GI. A competitive environment influences sperm production, but not testes tissue composition, in house mice. J Evol Biol 2018; 31:1647-1654. [DOI: 10.1111/jeb.13360] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 07/26/2018] [Accepted: 07/28/2018] [Indexed: 12/30/2022]
Affiliation(s)
- Renée C. Firman
- Centre for Evolutionary Biology School of Biological Sciences (M092) The University of Western Australia Crawley WA Australia
| | - Francisco Garcia‐Gonzalez
- Centre for Evolutionary Biology School of Biological Sciences (M092) The University of Western Australia Crawley WA Australia
- Estacion Biológica de Doñana CSIC Sevilla Spain
| | - Leigh W. Simmons
- Centre for Evolutionary Biology School of Biological Sciences (M092) The University of Western Australia Crawley WA Australia
| | - Gonçalo I. André
- Centre for Evolutionary Biology School of Biological Sciences (M092) The University of Western Australia Crawley WA Australia
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9
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André GI, Firman RC, Simmons LW. Phenotypic plasticity in genitalia: baculum shape responds to sperm competition risk in house mice. Proc Biol Sci 2018; 285:20181086. [PMID: 30051823 PMCID: PMC6053933 DOI: 10.1098/rspb.2018.1086] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 06/15/2018] [Indexed: 12/26/2022] Open
Abstract
Males are known to adjust their expenditure on testes growth and sperm production in response to sperm competition risk. Genital morphology can also contribute to competitive fertilization success but whether male genital morphology can respond plastically to the sperm competition environment has received little attention. Here, we exposed male house mice to two different sperm competition environments during their sexual development and quantified phenotypic plasticity in baculum morphology. The sperm competition environment generated plasticity in body growth. Males maturing under sperm competition risk were larger and heavier than males maturing under no sperm competition risk. We used a landmark-based geometric morphometric approach to measure baculum size and shape. Independent of variation in body size, males maintained under risk of sperm competition had a relatively thicker and more distally extended baculum bulb compared with males maintained under no sperm competition risk. Plasticity in baculum shape paralleled evolutionary responses to selection from sperm competition reported in previous studies of house mice. Our findings provide experimental evidence of socially mediated phenotypic plasticity in male genitalia.
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Affiliation(s)
- Gonçalo I André
- Centre for Evolutionary Biology, School of Biological Sciences (M092), The University of Western Australia, Crawley 6009, Australia
| | - Renée C Firman
- Centre for Evolutionary Biology, School of Biological Sciences (M092), The University of Western Australia, Crawley 6009, Australia
| | - Leigh W Simmons
- Centre for Evolutionary Biology, School of Biological Sciences (M092), The University of Western Australia, Crawley 6009, Australia
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10
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Gress BE, Pitnick S. Size-dependent ejaculation strategies and reproductive success in the yellow dung fly, Scathophaga stercoraria. Anim Behav 2017. [DOI: 10.1016/j.anbehav.2017.03.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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11
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Phillips A, Reichard M, Smith C. Sex differences in the responses to oviposition site cues by a fish revealed by tests with an artificial host. Anim Behav 2017. [DOI: 10.1016/j.anbehav.2017.02.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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12
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Pham MN, DeLecce T, Shackelford TK. Sperm competition in marriage: Semen displacement, male rivals, and spousal discrepancy in sexual interest. PERSONALITY AND INDIVIDUAL DIFFERENCES 2017. [DOI: 10.1016/j.paid.2016.09.056] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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13
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Ota K, Awata S, Morita M, Yokoyama R, Kohda M. Territorial males can sire more offspring in nests with smaller doors in the cichlid Lamprologus lemairii. J Hered 2014; 105:416-22. [PMID: 24574486 DOI: 10.1093/jhered/esu009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
To examine how territorial males counter reproductive parasites, we examined the paternity of broods guarded by territorial males using 5 microsatellite loci and factors that determine siring success in a wild population of the Lake Tanganyika cichlid Lamprologus lemairii. Females enter rock holes (nests) and spawn inside, and territorial males release milt over the nest openings. Sneakers attempt to dart into the nests, but territorial males often interrupt the attempt. The body size of territorial males (territorial defense ability) and the size of nest opening (the ability to prevent sneakers from nest intrusions) are predicted to be factors that affect paternity at the premating stage, whereas milt quality traits are factors that affect paternity at the postmating stage. Parentage analyses of 477 offspring revealed that most clutches have few or no cuckolders, and territorial males sired >80% of eggs in 7 of the 10 analyzed clutches. Larger territorial males that spawned in nests with narrower openings had greater siring success. In contrast, none of the milt traits affected the siring success. These suggest that territorial male L. lemairii adopt premating strategies whereby they effectively prevent reproductive parasitism.
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Affiliation(s)
- Kazutaka Ota
- the Department of Biology and Geosciences, Osaka City University, 3-3-138 Sumiyoshi, Osaka 558-8585, Japan
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14
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Liao CP, Yu D, Chen YY, Liu HZ. Reproductive behavior of the male rose bitterling Rhodeus ocellatus as influenced by the operational sex ratio. Zool Stud 2013. [DOI: 10.1186/1810-522x-52-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Abstract
Background
Game theory predicts that as the operational sex ratio (OSR; the ratio of sexually active males to fertilizable females) increases, reproductive males may adopt alternative reproductive behaviors. Empirical studies indicated that alternative behaviors may differ for different species. In the present study, we investigated the influence of different male-biased OSRs on male reproductive behaviors shown by a freshwater fish, the rose bitterling Rhodeus ocellatus.
Results
Six levels of the OSR (1:1, 2:1, 3:1, 5:1, 7:1, and 9:1) were established, and male leading, aggression, and preoviposition ejaculation behaviors were recorded. Our experiments showed that at low OSRs, the leading behavior of male rose bitterling increased with an increasing OSR, reaching a maximum at an OSR of 3:1, and then decreased as the OSR further increased. In contrast, aggression and preoviposition ejaculation behavior continually increased with an increasing OSR. Notably, males possibly lost their territorial position to other males and became sneakers when facing more rivals.
Conclusions
These observations suggest that at lower OSRs, male rose bitterling mainly rely on leading behavior, while at higher OSRs, they increasingly adopt aggression and preoviposition ejaculation. Therefore, for the rose bitterling, (1) decreased leading behavior and (2) increased aggression and preoviposition ejaculation are two alternative responses in the face of an increasing OSR, which is a more straightforward strategy for facing an increased risk of sperm competition than that adopted by its congener, the European bitterling.
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15
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Worthington AM, Gress BE, Neyer AA, Kelly CD. Do male crickets strategically adjust the number and viability of their sperm under sperm competition? Anim Behav 2013. [DOI: 10.1016/j.anbehav.2013.04.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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16
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Firman RC, Klemme I, Simmons LW. Strategic adjustments in sperm production within and between two island populations of house mice. Evolution 2013; 67:3061-70. [PMID: 24094355 DOI: 10.1111/evo.12164] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 04/18/2013] [Indexed: 11/28/2022]
Abstract
Sperm production is physiologically costly. Consequently, males are expected to be prudent in their sperm production, and tailor their expenditure according to prevailing social conditions. Differences in sperm production have been found across island populations of house mice that differ in the level of selection from sperm competition. Here, we determined the extent to which these differences represent phenotypic plasticity and/or population divergence in sperm production. We sourced individuals from two populations at the extreme levels of sperm competition, and raised them under common-garden conditions while manipulating the social experience of developing males. Males from the high-sperm competition population produced more sperm and better quality sperm than did males from the low-sperm competition population. In addition, males reared under a perceived "risk" of sperm competition produced greater numbers of sperm than males reared with "no risk." However, our analyses revealed that phenotypic plasticity in sperm production was greater for individuals from the high-sperm competition population. Our results are thus consistent with both population divergence and phenotypic plasticity in sperm production, and suggest that population level of sperm competition might affect the degree of adaptive plasticity in sperm production in response to sperm competition risk.
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Affiliation(s)
- Renée C Firman
- Centre for Evolutionary Biology, School of Animal Biology (M092), University of Western Australia, Nedlands, 6009, Australia.
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17
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Abstract
Sperm competition occurs when the spermatozoa of one male coincide with those of another to fertilise the same eggs. In some taxa males perform multiple ejaculations, which may function in sperm competition or in maintaining a baseline density of spermatozoa in the female reproductive tract to ensure fertilisation, a process that has been termed ‘topping up’. We investigated multiple ejaculations in the European bitterling (Rhodeus amarus), a freshwater fish that oviposits in freshwater mussels. We quantified spermatozoa in the mussel mantle cavity following ejaculation, and measured sperm motility parameters of males adopting different mating tactics. Following ejaculation spermatozoa density in the mussel increased linearly, peaked after 30 s, and then declined exponentially. Spermatozoa motility parameters did not differ between male mating tactics. We parameterised a model of sperm competition forR. amarus, which accurately predicted male fertilisation probability. We discuss these results in the context of multiple ejaculations and male mating tactics.
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Affiliation(s)
- Carl Smith
- Department of Biology, University of St Andrews, St Andrews, UK
- Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Brno, Czech Republic
| | - Martin Reichard
- Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Brno, Czech Republic
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18
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Spence R, Reichard M, Smith C. Strategic sperm allocation and a Coolidge effect in an externally fertilizing species. Behav Ecol 2012. [DOI: 10.1093/beheco/ars138] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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19
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Gumm JM. Sex recognition of female-like sneaker males in the Comanche Springs pupfish, Cyprinodon elegans. Anim Behav 2012. [DOI: 10.1016/j.anbehav.2012.03.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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20
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Shifferman EM. It's all in your head: the role of quantity estimation in sperm competition. Proc Biol Sci 2012; 279:833-40. [PMID: 22171084 PMCID: PMC3259941 DOI: 10.1098/rspb.2011.2256] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Accepted: 11/25/2011] [Indexed: 11/12/2022] Open
Abstract
The study of animal cognition has provided valuable data throughout the years, yet its reliance on laboratory work leaves some open questions. The main question is whether animals employ cognition in daily decision-making. The following discussion uses sperm competition (SC) as a test case for demonstrating the effect of cognition on routine choices, in this case, sexual selection. Cognition is manifested here by males' ability to represent the number of rivals competing with them. I claim that response to SC is driven by quantity estimation and the ability to assess competition magnitude cognitively. Hence, cognition can determine males' response to SC, and consequentially it can be selected within this context. This supports the argument that cognition constitutes an integral part of an individual's toolbox in solving real-life problems, and shows that physical and behavioural phenomena can expose cognition to selection and facilitate its evolution.
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Affiliation(s)
- Eran M Shifferman
- Konrad Lorenz Institute for Evolution and Cognition Research, Adolf Lorenz Gasse 2, 3422 Altenberg, Austria.
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21
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Reichard M, Smith C, Řežucha R. Personality traits, reproductive behaviour and alternative mating tactics in male European bitterling, Rhodeus amarus. BEHAVIOUR 2012. [DOI: 10.1163/156853912x643908] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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22
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Weir LK, Grant JWA, Hutchings JA. The influence of operational sex ratio on the intensity of competition for mates. Am Nat 2011; 177:167-76. [PMID: 21460553 DOI: 10.1086/657918] [Citation(s) in RCA: 188] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The evolution and maintenance of secondary sexual characteristics and behavior are heavily influenced by the variance in mating success among individuals in a population. The operational sex ratio (OSR) is often used as a predictor of the intensity of competition for mates, as it describes the relative number of males and females who are ready to mate. We investigate changes in aggression, courtship, mate guarding, and sperm release as a function of changes in the OSR using meta-analytic techniques. As the OSR becomes increasingly biased, aggression increases as competitors attempt to defend mates, but this aggression begins to decrease at an OSR of 1.99, presumably due to the increased costs of competition as rivals become more numerous. Sperm release follows a similar but not significant trend. By contrast, courtship rate decreases as the OSR becomes increasingly biased, whereas mate guarding and copulation duration increase. Overall, predictable behavioral changes occur in response to OSR, although the nature of the change is dependent on the type of mating behavior. These results suggest considerable flexibility of mating system structure within species, which can be predicted by OSR and likely results in variation in the strength of sexual selection.
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Affiliation(s)
- Laura K Weir
- Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada.
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23
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Kelly CD, Jennions MD. Sexual selection and sperm quantity: meta-analyses of strategic ejaculation. Biol Rev Camb Philos Soc 2011; 86:863-84. [PMID: 21414127 DOI: 10.1111/j.1469-185x.2011.00175.x] [Citation(s) in RCA: 214] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Clint D Kelly
- Department of Ecology, Evolution & Organismal Biology, Iowa State University, Ames, USA.
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25
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BRETMAN AMANDA, NEWCOMBE DEVI, TREGENZA TOM. Promiscuous females avoid inbreeding by controlling sperm storage. Mol Ecol 2009; 18:3340-5. [DOI: 10.1111/j.1365-294x.2009.04301.x] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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26
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Smith C, Pateman-Jones C, Zięba G, Przybylski M, Reichard M. Sperm depletion as a consequence of increased sperm competition risk in the European bitterling, Rhodeus amarus. Anim Behav 2009. [DOI: 10.1016/j.anbehav.2009.01.027] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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27
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Evans JP. No evidence for sperm priming responses under varying sperm competition risk or intensity in guppies. Naturwissenschaften 2009; 96:771-9. [DOI: 10.1007/s00114-009-0529-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2009] [Revised: 03/10/2009] [Accepted: 03/10/2009] [Indexed: 10/21/2022]
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28
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Bretman A, Fricke C, Chapman T. Plastic responses of male Drosophila melanogaster to the level of sperm competition increase male reproductive fitness. Proc Biol Sci 2009; 276:1705-11. [PMID: 19324834 DOI: 10.1098/rspb.2008.1878] [Citation(s) in RCA: 175] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Evolutionary and plastic responses by males to the level of sperm competition (SC) are reported across widespread taxa, but direct tests of the consequences for male reproductive success in a competitive context are lacking. We varied male perception of SC to examine the effect on male competitive reproductive success and to test whether the outcomes were as predicted by theory. Exposure to rival males prior to mating increased a male's ejaculate investment (measured as mating duration); by contrast, exposure to rival males in the mating arena decreased mating duration. The results therefore suggested that SC intensity is important in shaping male responses to SC in this system, although the patterns were not strictly in accord with existing theory. We then tested whether males that responded to the level of SC had higher reproductive fitness in a competitive context. We found that males kept with rivals prior to mating again mated for longer; furthermore, they achieved significantly higher paternity share regardless of whether they were the first or second males to mate with a female. The plastic strategies employed by males therefore resulted in significantly increased reproductive success in a competitive context, even following subsequent rematings in which the majority of sperm were displaced.
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Affiliation(s)
- Amanda Bretman
- School of Biological Sciences, University of East Anglia, Norwich, Norfolk NR4 7TJ, UK
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29
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Thomas ML, Simmons LW. Male-derived cuticular hydrocarbons signal sperm competition intensity and affect ejaculate expenditure in crickets. Proc Biol Sci 2009; 276:383-8. [PMID: 18854298 DOI: 10.1098/rspb.2008.1206] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Female sexual promiscuity can have significant effects on male mating decisions because it increases the intensity of competition between ejaculates for fertilization. Because sperm production is costly, males that can detect multiple matings by females and allocate sperm strategically will have an obvious fitness advantage. The presence of rival males is widely recognized as a cue used by males to assess sperm competition. However, for species in which males neither congregate around nor guard females, other more cryptic cues might be involved. Here, we demonstrate unprecedented levels of sperm competition assessment by males, which is mediated via the use of chemical cues. Using the cricket Teleogryllus oceanicus, we manipulated male perception of sperm competition by experimentally coating live unmated females with cuticular compounds extracted from males. We found that males adjusted their ejaculate allocation in response to these compounds: the viability of sperm contained within a male's ejaculate decreased as the number of male extracts applied to his virgin female partner was increased. We further show that males do not respond to the relative concentration of male compounds present on females, but rather to the number of distinct signature odours of individual males. Our results conform to sperm competition theory, and show for the first time, to our knowledge, that males can detect different intensities of sperm competition by using distinct chemical cues of individual males present on females.
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Affiliation(s)
- Melissa L Thomas
- Centre for Evolutionary Biology, School of Animal Biology, The University of Western Australia, Crawley, Western Australia 6009, Australia.
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30
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Wong BBM, McCarthy M. Prudent male mate choice under perceived sperm competition risk in the eastern mosquito fish. Behav Ecol 2009. [DOI: 10.1093/beheco/arp010] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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31
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Dzieweczynski TL, Lyman S, Poor EA. Male Siamese Fighting Fish,Betta splendens, Increase Rather than Conceal Courtship Behavior when a Rival is Present. Ethology 2009. [DOI: 10.1111/j.1439-0310.2008.01602.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Vaughn AA, Delbarco-Trillo J, Ferkin MH. Sperm investment in male meadow voles is affected by the condition of the nearby male conspecifics. ACTA ACUST UNITED AC 2008; 19:1159-1164. [PMID: 19529815 DOI: 10.1093/beheco/arn092] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2008] [Revised: 06/13/2008] [Accepted: 06/19/2008] [Indexed: 11/14/2022]
Abstract
Sperm competition occurs when 2 or more males copulate with a particular female during the same reproductive cycle, and their sperm compete to fertilize the female's available eggs. One strategy that male voles use to assess the risk and intensity of sperm competition involves responding to the presence of scent marks of conspecific males found near a sexually receptive female. Previously, we have shown that if a male vole copulated with a female while he was in the presence of the odors of another male he increased his sperm investment relative to his investment if another male's odors were not present. The aim of the present study was to test the hypothesis that males assess differences in the relative quality of competing males and adjust their sperm investment accordingly. We did so by allowing males to copulate when they were exposed to the scent mark of a 24-h food-deprived male (low-quality male) or the scent mark of a male that was not food deprived (high-quality male). The data indicate that male meadow voles did not increase their sperm investment during copulation when exposed to the scent mark of a food-deprived male but did so when they were exposed to the scent mark of a male that was not food deprived. The results support the hypothesis that male voles are able to adjust sperm investment when they encounter the scent marks of males that differ in quality.
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Affiliation(s)
- Ashlee A Vaughn
- Department of Biology, University of Memphis, Ellington Hall, Memphis, TN 38152, USA
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Thomas ML, Simmons LW. Male Crickets Adjust the Viability of Their Sperm in Response to Female Mating Status. Am Nat 2007; 170:190-5. [PMID: 17874370 DOI: 10.1086/519404] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2006] [Accepted: 03/14/2007] [Indexed: 11/03/2022]
Abstract
Sperm competition theory predicts that males should allocate sperm according to the number of competing ejaculates. Prudent allocation of sperm in response to different levels of sperm competition has been found across a number of taxa; however, some studies suggest that males may not always allocate sperm as expected. Here we examine sperm allocation in the Australian field cricket Teleogryllus oceanicus, using female mating status (virgin, singly mated, or multiply mated) to manipulate male perception of sperm competition risk and intensity. Consistent with theory, we found that male crickets adjust their ejaculates in response to female mating status. However, rather than altering the absolute numbers of sperm transferred to a female, males altered the quality of their sperm. Males ejaculated sperm of low viability (proportion of live vs. dead sperm) when mating with virgins, increased sperm viability when mating with singly mated females, but reduced sperm viability when mating with multiply mated females. Our results show that variation in ejaculate quality can be an important aspect of strategic ejaculation by males and suggest caution in the interpretation of studies in which males do not appear to allocate sperm according to theory.
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Affiliation(s)
- Melissa L Thomas
- Centre for Evolutionary Biology, School of Animal Biology, University of Western Australia, Crawley, Western Australia 6009, Australia.
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34
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Aspbury AS. Sperm competition effects on sperm production and expenditure in sailfin mollies, Poecilia latipinna. Behav Ecol 2007. [DOI: 10.1093/beheco/arm044] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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35
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Risk of sperm competition does not influence copulatory behavior in the promiscuous meadow vole (Microtus pennsylvanicus). J ETHOL 2006. [DOI: 10.1007/s10164-006-0008-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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36
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delBarco-Trillo J, Ferkin MH. Male meadow voles respond differently to risk and intensity of sperm competition. Behav Ecol 2006. [DOI: 10.1093/beheco/ark001] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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37
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Awata S, Heg D, Munehara H, Kohda M. Testis size depends on social status and the presence of male helpers in the cooperatively breeding cichlid Julidochromis ornatus. Behav Ecol 2006. [DOI: 10.1093/beheco/arj043] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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38
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Scaggiante M, Rasotto MB, Romualdi C, Pilastro A. Territorial male gobies respond aggressively to sneakers but do not adjust their sperm expenditure. Behav Ecol 2005. [DOI: 10.1093/beheco/ari081] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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39
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Benefits and costs to mussels from ejecting bitterling embryos: a test of the evolutionary equilibrium hypothesis. Anim Behav 2005. [DOI: 10.1016/j.anbehav.2004.09.016] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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40
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Reichard M, Bryja J, Ondracková M, Dávidová M, Kaniewska P, Smith C. Sexual selection for male dominance reduces opportunities for female mate choice in the European bitterling (Rhodeus sericeus). Mol Ecol 2005; 14:1533-42. [PMID: 15813791 DOI: 10.1111/j.1365-294x.2005.02534.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Sexual selection involves two main mechanisms: intrasexual competition for mates and intersexual mate choice. We experimentally separated intrasexual (male-male interference competition) and intersexual (female choice) components of sexual selection in a freshwater fish, the European bitterling (Rhodeus sericeus). We compared the roles of multiple morphological and behavioural traits in male success in both components of sexual competition, and their relation to male reproductive success, measured as paternity of offspring. Body size was important for both female choice and male-male competition, though females also preferred males that courted more vigorously. However, dominant males often monopolized females regardless of female preference. Subordinate males were not excluded from reproduction and sired some offspring, possibly through sneaked ejaculations. Male dominance and a greater intensity of carotenoid-based red colouration in their iris were the best predictors of male reproductive success. The extent of red iris colouration and parasite load did not have significant effects on female choice, male dominance or male reproductive success. No effect of parasite load on the expression of red eye colouration was detected, though this may have been due to low parasite prevalence in males overall. In conclusion, we showed that even though larger body size was favoured in both intersexual and intrasexual selection, male-male interference competition reduced opportunities for female choice. Females, despite being choosy, had limited control over the paternity of their offspring. Our study highlights the need for reliable measures of male reproductive success in studies of sexual selection.
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Affiliation(s)
- M Reichard
- Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Brno, Czech Republic.
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41
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Abstract
As females of many species mate with more than one male, ejaculates often face competition from the sperm of other males. In recent years, numerous papers have been published on theoretical predictions of evolutionary, behavioural and physiological responses to variation in the strength of sperm competition (SC). These theoretical predictions have also been extensively tested. However, although predictions from SC theory are relatively straightforward, extra caution has to be paid in the design of experiments testing them. One difficulty is for example to disentangle immediate and mean SC risk and intensity. Without carefully designed experiments, it is also very easy to simultaneously increase SC risk and the probability of intense SC--a situation for which we currently have no clear predictions, as the theoretical models to date only assume variation in either SC risk or intensity. In this paper, we discuss these and some other pitfalls related to manipulations of SC risk and intensity and suggest how to avoid them.
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Affiliation(s)
- L Engqvist
- Institut für Evolutionsbiologie und Okologie, Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany.
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42
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Byrne PG. Male sperm expenditure under sperm competition risk and intensity in quacking frogs. Behav Ecol 2004. [DOI: 10.1093/beheco/arh098] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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43
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Reichard M, Smith C, Jordan WC. Genetic evidence reveals density-dependent mediated success of alternative mating behaviours in the European bitterling (Rhodeus sericeus). Mol Ecol 2004; 13:1569-78. [PMID: 15140099 DOI: 10.1111/j.1365-294x.2004.02151.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reproductive success of alternative mating behaviours may vary within and among populations in relation to environmental factors and demographic parameters. We used behavioural and genetic data to investigate how male density affects reproductive success of territoriality and sneaking in the European bitterling (Rhodeus sericeus, Cyprinidae), a freshwater fish that spawns on the gills of living freshwater mussels. Keeping the number of spawning sites constant, we manipulated male densities in laboratory and mesocosm experiments. We showed that sneaked fertilizations were common in R. sericeus, and that they increased significantly with male density. Territorial mating was almost 17 times more successful than sneaking at the lowest male density treatment, and still 2-3 times more successful at intermediate densities. However, both behaviours conferred the same fitness pay-off at the highest male density. While the success of territorial males declined with male density, the success of individual sneaking males remained constant across densities. Notably, the capacity of territorial males to outcompete sneakers by preoviposition sperm loading was the best predictor of male reproductive success, rather than aggression, body size or postoviposition ejaculation.
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Affiliation(s)
- M Reichard
- Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Kvetná 8, 603 65 Brno, Czech Republic.
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Mills SC, Reynolds JD. Operational sex ratio and alternative reproductive behaviours in the European bitterling, Rhodeus sericeus. Behav Ecol Sociobiol 2003. [DOI: 10.1007/s00265-003-0616-1] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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46
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Abstract
Many female insects mate with multiple males within a single fertile period despite costs such as expenditure of energy and time and contraction of sexually transmitted diseases. In the red flour beetle, Tribolium castaneum, females remate with different males within minutes of the first copulation. If rapid multiple mating is adaptive then multiply mated females should have higher fitness than singly mated females. In this study, we determined the remating frequency of female beetles, characterized female mating behavior, and examined the fitness consequences of female multiple mating. We found that female T. castaneum mated, on average, with 46 nonvirgin males within a 1-h observation period. The number of males present in a mating arena did not significantly affect copulation frequency or the intermating interval. However, number of males present significantly affected the length of a single copula as a result of disturbance by rival males when more males were present. Female mating with multiple males in 24 h did not significantly improve egg production, F1-adult production, egg-to-adult viability, fertility retention, and female survivorship. Thus, multiple mating did not enhance long-term female fitness. Polyandrous mating behavior may have evolved through other mechanisms such as fertility assurance and increased offspring genetic diversity or fitness.
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