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Míčková K, Jelínek V, Tomášek O, Stopková R, Stopka P, Albrecht T. Proteomic analysis reveals dynamic changes in cloacal fluid composition during the reproductive season in a sexually promiscuous passerine. Sci Rep 2024; 14:14259. [PMID: 38902251 PMCID: PMC11190206 DOI: 10.1038/s41598-024-62244-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Accepted: 05/15/2024] [Indexed: 06/22/2024] Open
Abstract
Cryptic female choice (CFC) is a component of postcopulatory sexual selection that allows females to influence the fertilization success of sperm from different males. While its precise mechanisms remain unclear, they may involve the influence of the protein composition of the female reproductive fluids on sperm functionality. This study maps the protein composition of the cloacal fluid across different phases of female reproductive cycle in a sexually promiscuous passerine, the barn swallow. Similar to mammals, the protein composition in the female reproductive tract differed between receptive (when females copulate) and nonreceptive phases. With the change in the protein background, the enriched gene ontology terms also shifted. Within the receptive phase, distinctions were observed between proteomes sampled just before and during egg laying. However, three proteins exhibited increased abundance during the entire receptive phase compared to nonreceptive phases. These proteins are candidates in cryptic female choice, as all of them can influence the functionality of sperm or sperm-egg interaction. Our study demonstrates dynamic changes in the cloacal environment throughout the avian breeding cycle, emphasizing the importance of considering these fluctuations in studies of cryptic female choice.
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Affiliation(s)
- Kristýna Míčková
- Department of Zoology, Faculty of Science, Charles University, Prague, Czech Republic
- Institute of Vertebrate Biology, The Czech Academy of Sciences, Brno, Czech Republic
| | - Václav Jelínek
- Institute of Vertebrate Biology, The Czech Academy of Sciences, Brno, Czech Republic
| | - Oldřich Tomášek
- Institute of Vertebrate Biology, The Czech Academy of Sciences, Brno, Czech Republic
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Romana Stopková
- Department of Zoology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Pavel Stopka
- Department of Zoology, Faculty of Science, Charles University, Prague, Czech Republic.
| | - Tomáš Albrecht
- Department of Zoology, Faculty of Science, Charles University, Prague, Czech Republic.
- Institute of Vertebrate Biology, The Czech Academy of Sciences, Brno, Czech Republic.
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2
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Mahdjoub H, Khelifa R, Roy J, Sbilordo SH, Zeender V, Perdigón Ferreira J, Gourgoulianni N, Lüpold S. Interplay between male quality and male-female compatibility across episodes of sexual selection. SCIENCE ADVANCES 2023; 9:eadf5559. [PMID: 37774022 PMCID: PMC10541500 DOI: 10.1126/sciadv.adf5559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 08/30/2023] [Indexed: 10/01/2023]
Abstract
The processes underlying mate choice profoundly influence the dynamics of sexual selection and the evolution of male sexual traits. Consistent preference for certain phenotypes may erode genetic variation in populations through directional selection, whereas divergent preferences (e.g., genetically compatible mates) provide one mechanism to maintain such variation. However, the relative contributions of these processes across episodes of selection remain unknown. Using Drosophila melanogaster, we followed the fate of male genotypes, previously scored for their overall reproductive value and their compatibility with different female genotypes, across pre- and postmating episodes of selection. When pairs of competitor males differed in their intrinsic quality and their compatibility with the female, both factors influenced outcomes from mating success to paternity but to a varying degree between stages. These results add further dimensions to our understanding of how the interactions between genotypes and forms of selection shape reproductive outcomes and ultimately reproductive trait evolution.
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Affiliation(s)
- Hayat Mahdjoub
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
- Biology Department, Concordia University, 7141 Sherbrooke St. W., Montreal QC H4B 1R6, Canada
| | - Rassim Khelifa
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
- Biology Department, Concordia University, 7141 Sherbrooke St. W., Montreal QC H4B 1R6, Canada
| | - Jeannine Roy
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Sonja H. Sbilordo
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Valérian Zeender
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Jhoniel Perdigón Ferreira
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Natalia Gourgoulianni
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Stefan Lüpold
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
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3
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Lantiegne TH, Purchase CF. Can cryptic female choice prevent invasive hybridization in external fertilizing fish? Evol Appl 2023; 16:1412-1421. [PMID: 37622094 PMCID: PMC10445091 DOI: 10.1111/eva.13573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 06/08/2023] [Indexed: 08/26/2023] Open
Abstract
Polyandrous mating systems result in females mating with multiple males, generating opportunities for strong pre-mating and post-mating sexual selection. Polyandry also creates the potential for unintended matings and subsequent sperm competition with hybridizing species. Cryptic female choice allows females to bias paternity towards preferred males under sperm competition and may include conspecific sperm preference when under hybridization risk. The potential for hybridization becomes particularly important in context of invasive species that can novelly hybridize with natives, and by definition, have evolved allopatrically. We provide the first examination of conspecific sperm preference in a system of three species with the potential to hybridize: North American native Atlantic salmon (Salmo salar) and brook char (Salvelinus fontinalis), and invasive brown trout (Salmo trutta) from Europe. Using naturalized populations on the island of Newfoundland, we measured changes in sperm swimming performance, a known predictor of paternity, to determine the degree of modification in sperm swimming to female cues related to conspecific sperm preference. Compared to water alone, female ovarian fluid in general had a pronounced effect and changed sperm motility (by a mean of 53%) and swimming velocity (mean 30%), but not linearity (mean 6%). However, patterns in the degree of modification suggest there is no conspecific sperm preference in the North American populations. Furthermore, female cues from both native species tended to boost the sperm of invasive males more than their own. We conclude that cryptic female choice via ovarian fluid mediated sperm swimming modification is too weak in this system to prevent invasive hybridization and is likely insufficient to promote or maintain reproductive isolation between the native North American species.
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Affiliation(s)
- Tyler H. Lantiegne
- Department of BiologyMemorial University of NewfoundlandSt. John'sNewfoundland & LabradorCanada
| | - Craig F. Purchase
- Department of BiologyMemorial University of NewfoundlandSt. John'sNewfoundland & LabradorCanada
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4
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Spezie G, Fusani L. Sneaky copulations by subordinate males suggest direct fitness benefits from male-male associations in spotted bowerbirds ( Ptilonorhynchus maculatus). Ethology 2023; 129:55-61. [PMID: 37063455 PMCID: PMC10092701 DOI: 10.1111/eth.13336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 09/08/2022] [Accepted: 09/09/2022] [Indexed: 11/29/2022]
Abstract
Male spotted bowerbirds (Ptilonorhynchus maculatus) build and defend a structure of sticks and straw-the bower-decorated with colourful objects to attract mates during the breeding season. Specific non-territorial, subordinate males are tolerated by resident males at bowers over multiple breeding seasons. Prior research showed that these male-male associations exhibit attributes of coalitionary behaviour and that subordinate males gain delayed benefits from associating with bower owners, namely future bower inheritance. Yet, it remained unclear whether subordinate males may additionally gain direct fitness benefits from attending established bowers. Here, we report on four separate instances of sneaky copulations (or attempts of copulating) by subordinate males at resident males' bowers. Multiple non-resident males disrupted the ongoing copulations between the bower owner and a receptive female, and these events were followed by violent aggressive interactions. These observations shed new light on same-sex social dynamics in spotted bowerbirds and support the hypothesis that subordinate males are sexually mature individuals that occasionally obtain access to females while attending established bowers. We discuss these findings in light of the literature on male courtship coalitions and agonistic behaviour in bowerbirds, and highlight further aspects of subordinate behaviour that require empirical investigation.
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Affiliation(s)
- Giovanni Spezie
- Konrad Lorenz Institute of EthologyUniversity of Veterinary MedicineViennaAustria
| | - Leonida Fusani
- Konrad Lorenz Institute of EthologyUniversity of Veterinary MedicineViennaAustria
- Department of Behavioural and Cognitive BiologyUniversity of ViennaViennaAustria
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5
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Pandulli‐Alonso I, Tomasco IH, Albo MJ. The handsome liar: Male spiders offering worthless gifts can benefit increasing mating duration. Ethology 2021. [DOI: 10.1111/eth.13258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Irene Pandulli‐Alonso
- Departamento de Ecología y Biología Evolutiva Instituto de Investigaciones Biológicas Clemente Estable Montevideo Uruguay
| | - Ivanna H. Tomasco
- Departamento de Ecología y Evolución. Facultad de Ciencias Universidad de la República Montevideo Uruguay
| | - Maria J. Albo
- Departamento de Ecología y Biología Evolutiva Instituto de Investigaciones Biológicas Clemente Estable Montevideo Uruguay
- Departamento de Ecología y Evolución. Facultad de Ciencias Universidad de la República Montevideo Uruguay
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6
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Carleial R, McDonald GC, Spurgin LG, Fairfield EA, Wang Y, Richardson DS, Pizzari T. Temporal dynamics of competitive fertilization in social groups of red junglefowl ( Gallus gallus) shed new light on avian sperm competition. Philos Trans R Soc Lond B Biol Sci 2020; 375:20200081. [PMID: 33070718 PMCID: PMC7661449 DOI: 10.1098/rstb.2020.0081] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/26/2020] [Indexed: 01/28/2023] Open
Abstract
Studies of birds have made a fundamental contribution to elucidating sperm competition processes, experimentally demonstrating the role of individual mechanisms in competitive fertilization. However, the relative importance of these mechanisms and the way in which they interact under natural conditions remain largely unexplored. Here, we conduct a detailed behavioural study of freely mating replicate groups of red junglefowl, Gallus gallus, to predict the probability that competing males fertilize individual eggs over the course of 10-day trials. Remating frequently with a female and mating last increased a male's probability of fertilization, but only for eggs ovulated in the last days of a trial. Conversely, older males, and those mating with more polyandrous females, had consistently lower fertilization success. Similarly, resistance to a male's mating attempts, particularly by younger females, reduced fertilization probability. After considering these factors, male social status, partner relatedness and the estimated state of male extragonadal sperm reserves did not predict sperm competition outcomes. These results shed new light on sperm competition dynamics in taxa such as birds, with prolonged female sperm storage and staggered fertilizations. This article is part of the theme issue 'Fifty years of sperm competition'.
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Affiliation(s)
- Rômulo Carleial
- Department of Zoology, Edward Grey Institute, University of Oxford, Oxford OX1 3SZ, UK
| | - Grant C. McDonald
- Department of Zoology, Edward Grey Institute, University of Oxford, Oxford OX1 3SZ, UK
- Department of Ecology, University of Veterinary Medicine Budapest, Budapest 1077, Hungary
| | - Lewis G. Spurgin
- School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK
| | | | - Yunke Wang
- Department of Zoology, Edward Grey Institute, University of Oxford, Oxford OX1 3SZ, UK
| | - David S. Richardson
- School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK
| | - Tommaso Pizzari
- Department of Zoology, Edward Grey Institute, University of Oxford, Oxford OX1 3SZ, UK
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7
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Lüpold S, Reil JB, Manier MK, Zeender V, Belote JM, Pitnick S. How female × male and male × male interactions influence competitive fertilization in Drosophila melanogaster. Evol Lett 2020; 4:416-429. [PMID: 33014418 PMCID: PMC7523561 DOI: 10.1002/evl3.193] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 08/02/2020] [Accepted: 08/13/2020] [Indexed: 01/01/2023] Open
Abstract
How males and females contribute to joint reproductive success has been a long‐standing question in sexual selection. Under postcopulatory sexual selection, paternity success is predicted to derive from complex interactions among females engaging in cryptic female choice and males engaging in sperm competition. Such interactions have been identified as potential sources of genetic variation in sexually selected traits but are also expected to inhibit trait diversification. To date, studies of interactions between females and competing males have focused almost exclusively on genotypes and not phenotypic variation in sexually selected traits. Here, we characterize within‐ and between‐sex interactions in Drosophila melanogaster using isogenic lines with heritable variation in both male and female traits known to influence competitive fertilization. We confirmed, and expanded on, previously reported genotypic interactions within and between the sexes, and showed that several reproductive events, including sperm transfer, female sperm ejection, and sperm storage, were explained by two‐ and three‐way interactions among sex‐specific phenotypes. We also documented complex interactions between the lengths of competing males’ sperm and the female seminal receptacle, which are known to have experienced rapid female‐male co‐diversification. Our results highlight the nonindependence of sperm competition and cryptic female choice and demonstrate that complex interactions between the sexes do not limit the ability of multivariate systems to respond to directional sexual selection.
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Affiliation(s)
- Stefan Lüpold
- Department of Evolutionary Biology and Environmental Studies University of Zurich Zurich CH-8057 Switzerland.,Department of Biology Syracuse University Syracuse New York 13244
| | - Jonathan Bradley Reil
- Department of Entomology Cornell University Ithaca New York 14853.,Department of Plant and Environmental Protection Sciences University of Hawaii at Mānoa Honolulu Hawaii 96822
| | - Mollie K Manier
- Department of Biology Syracuse University Syracuse New York 13244.,Department of Biological Sciences George Washington University Washington DC 20052
| | - Valérian Zeender
- Department of Evolutionary Biology and Environmental Studies University of Zurich Zurich CH-8057 Switzerland
| | - John M Belote
- Department of Biology Syracuse University Syracuse New York 13244
| | - Scott Pitnick
- Department of Biology Syracuse University Syracuse New York 13244
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8
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Moehring AJ, Boughman JW. Veiled preferences and cryptic female choice could underlie the origin of novel sexual traits. Biol Lett 2019; 15:20180878. [PMID: 30958124 DOI: 10.1098/rsbl.2018.0878] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Males in many species have elaborated sexual traits that females strongly prefer, and these traits often conspicuously differ among species. How novel preferences and traits originate, however, is a challenging evolutionary problem because the initial appearance of only the female preference or only the male trait should reduce the ability to find a suitable mate, which could reduce fitness for individuals possessing those novel alleles. Here, we present a hypothesis for how novel preferences, as well as the novel male traits that females prefer, can originate, be favoured and spread in polyandrous species. Novel preference mutations can arise as 'veiled preferences' that are not expressed when the corresponding male trait is not present in the population, allowing preferences to be hidden from selection, and thus persist. In those cases when a male trait is present, veiled preferences provide a selective advantage, and females disproportionately produce offspring from preferred males through either mate choice or cryptic female choice. This tips the fitness advantage for novel males, allowing both preference and trait to spread, and limiting selection against them in the absence of the corresponding trait or preference.
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Affiliation(s)
- Amanda J Moehring
- 1 Department of Biology, Western University , London, ON , Canada N6A 5B7
| | - Janette W Boughman
- 2 Ecology, Evolutionary Biology and Behavior Program, Michigan State University , East Lansing, MI 48824 , USA
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9
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Carleial R, McDonald GC, Pizzari T. Dynamic phenotypic correlates of social status and mating effort in male and female red junglefowl, Gallus gallus. J Evol Biol 2019; 33:22-40. [PMID: 31529557 PMCID: PMC6972591 DOI: 10.1111/jeb.13541] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 09/10/2019] [Accepted: 09/11/2019] [Indexed: 11/30/2022]
Abstract
Despite widespread evidence that mating and intrasexual competition are costly, relatively little is known about how these costs dynamically change male and female phenotypes. Here, we test multiple hypotheses addressing this question in replicate flocks of red junglefowl (Gallus gallus). First, we test the interrelationships between social status, comb size (a fleshy ornament) and body mass at the onset of a mating trial. While comb size covaried positively with body mass across individuals of both sexes, comb size was positively related to social status in females but not in males. Second, we test for changes within individuals in body mass and comb size throughout the mating trial. Both body mass and comb size declined at the end of a trial in both sexes, suggesting that mating effort and exposure to the opposite sex are generally costly. Males lost more body mass if they (a) were socially subordinate, (b) were chased by other males or (c) mated frequently, indicating that subordinate status and mating are independently costly. Conversely, females lost more body mass if they were exposed to a higher frequency of coerced matings, suggesting costs associated with male sexual harassment and female resistance, although costs of mating per se could not be completely ruled out. Neither competitive nor mating interactions predicted comb size change in either sex. Collectively, these results support the notion that sex‐specific costs associated with social status and mating effort result in differential, sex‐specific dynamics of phenotypic change.
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Affiliation(s)
- Rômulo Carleial
- Edward Grey Institute, Department of Zoology, University of Oxford, Oxford, UK
| | - Grant C McDonald
- Edward Grey Institute, Department of Zoology, University of Oxford, Oxford, UK.,Department of Ecology, University of Veterinary Medicine Budapest, Budapest, Hungary
| | - Tommaso Pizzari
- Edward Grey Institute, Department of Zoology, University of Oxford, Oxford, UK
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10
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Pizzari T, McDonald GC. Sexual selection in socially-structured, polyandrous populations: Some insights from the fowl. ADVANCES IN THE STUDY OF BEHAVIOR 2019. [DOI: 10.1016/bs.asb.2019.02.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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11
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Patrício AR, Varela MR, Barbosa C, Broderick AC, Ferreira Airaud MB, Godley BJ, Regalla A, Tilley D, Catry P. Nest site selection repeatability of green turtles, Chelonia mydas, and consequences for offspring. Anim Behav 2018. [DOI: 10.1016/j.anbehav.2018.03.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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12
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Sanchez-Donoso I, Vilà C, Puigcerver M, Rodríguez-Teijeiro JD. Mate guarding and male body condition shape male fertilization success and female mating system in the common quail. Anim Behav 2018. [DOI: 10.1016/j.anbehav.2017.12.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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13
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Zohdy S, Bisanzio D, Tecot S, Wright PC, Jernvall J. Aggression and hormones are associated with heterogeneity in parasitism and parasite dynamics in the brown mouse lemur. Anim Behav 2017. [DOI: 10.1016/j.anbehav.2017.08.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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14
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Postmating Female Control: 20 Years of Cryptic Female Choice. Trends Ecol Evol 2017; 32:368-382. [PMID: 28318651 PMCID: PMC5511330 DOI: 10.1016/j.tree.2017.02.010] [Citation(s) in RCA: 196] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 02/08/2017] [Accepted: 02/09/2017] [Indexed: 12/22/2022]
Abstract
Cryptic female choice (CFC) represents postmating intersexual selection arising from female-driven mechanisms at or after mating that bias sperm use and impact male paternity share. Although biologists began to study CFC relatively late, largely spurred by Eberhard's book published 20 years ago, the field has grown rapidly since then. Here, we review empirical progress to show that numerous female processes offer potential for CFC, from mating through to fertilization, although seldom has CFC been clearly demonstrated. We then evaluate functional implications, and argue that, under some conditions, CFC might have repercussions for female fitness, sexual conflict, and intersexual coevolution, with ramifications for related evolutionary phenomena, such as speciation. We conclude by identifying directions for future research in this rapidly growing field.
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15
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Tan CKW, Doyle P, Bagshaw E, Richardson DS, Wigby S, Pizzari T. The contrasting role of male relatedness in different mechanisms of sexual selection in red junglefowl. Evolution 2017; 71:403-420. [PMID: 27925168 PMCID: PMC5324671 DOI: 10.1111/evo.13145] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 11/08/2016] [Indexed: 12/25/2022]
Abstract
In structured populations, competition for reproductive opportunities should be relaxed among related males. The few tests of this prediction often neglect the fact that sexual selection acts through multiple mechanisms, both before and after mating. We performed experiments to study the role of within-group male relatedness across pre- and postcopulatory mechanisms of sexual selection in social groups of red junglefowl, Gallus gallus, in which two related males and one unrelated male competed over females unrelated to all the males. We confirm theoretical expectations that, after controlling for male social status, competition over mating was reduced among related males. However, this effect was contrasted by other sexual selection mechanisms. First, females biased male mating in favor of the unrelated male, and might also favor his inseminations after mating. Second, males invested more-rather than fewer-sperm in postcopulatory competition with relatives. A number of factors may contribute to explain this counterintuitive pattern of sperm allocation, including trade-offs between male investment in pre- versus postcopulatory competition, differences in the relative relatedness of pre- versus postcopulatory competitors, and female bias in sperm utilization in response to male relatedness. Collectively, these results reveal that within-group male relatedness may have contrasting effects in different mechanisms of sexual selection.
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Affiliation(s)
- Cedric Kai Wei Tan
- Department of ZoologyEdward Grey Institute, University of OxfordOxfordOX1 3PSUnited Kingdom
| | - Philippa Doyle
- Department of ZoologyEdward Grey Institute, University of OxfordOxfordOX1 3PSUnited Kingdom
| | - Emma Bagshaw
- Department of ZoologyEdward Grey Institute, University of OxfordOxfordOX1 3PSUnited Kingdom
| | - David S. Richardson
- School of Biological SciencesUniversity of East AngliaNorwichNR4 7TJUnited Kingdom
| | - Stuart Wigby
- Department of ZoologyEdward Grey Institute, University of OxfordOxfordOX1 3PSUnited Kingdom
| | - Tommaso Pizzari
- Department of ZoologyEdward Grey Institute, University of OxfordOxfordOX1 3PSUnited Kingdom
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16
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Borziak K, Álvarez-Fernández A, L Karr T, Pizzari T, Dorus S. The Seminal fluid proteome of the polyandrous Red junglefowl offers insights into the molecular basis of fertility, reproductive ageing and domestication. Sci Rep 2016; 6:35864. [PMID: 27804984 PMCID: PMC5090203 DOI: 10.1038/srep35864] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 10/06/2016] [Indexed: 02/03/2023] Open
Abstract
Seminal fluid proteins (SFPs) are emerging as fundamental contributors to sexual selection given their role in post-mating reproductive events, particularly in polyandrous species where the ejaculates of different males compete for fertilisation. SFP identification however remains taxonomically limited and little is known about avian SFPs, despite extensive work on sexual selection in birds. We characterize the SF proteome of the polyandrous Red junglefowl, Gallus gallus, the wild species that gave rise to the domestic chicken. We identify 1,141 SFPs, including proteins involved in immunity and antimicrobial defences, sperm maturation, and fertilisation, revealing a functionally complex SF proteome. This includes a predominant contribution of blood plasma proteins that is conserved with human SF. By comparing the proteome of young and old males with fast or slow sperm velocity in a balanced design, we identify proteins associated with ageing and sperm velocity, and show that old males that retain high sperm velocity have distinct proteome characteristics. SFP comparisons with domestic chickens revealed both qualitative and quantitative differences likely associated with domestication and artificial selection. Collectively, these results shed light onto the functional complexity of avian SF, and provide a platform for molecular studies of fertility, reproductive ageing, and domestication.
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Affiliation(s)
- Kirill Borziak
- Center for Reproductive Evolution, Department of Biology, Syracuse University, US
| | | | - Timothy L Karr
- Drosophila Genetic Resource Center, Kyoto Institute of Technology, Saga Ippongi-cho, Ukyo-ku, Kyoto 616-8354, Japan
| | - Tommaso Pizzari
- Edward Grey Institute, Department of Zoology, University of Oxford, UK
| | - Steve Dorus
- Center for Reproductive Evolution, Department of Biology, Syracuse University, US
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17
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Pizzari T. The Wood-Gush legacy: A sociobiology perspective to fertility and welfare in chickens. Appl Anim Behav Sci 2016. [DOI: 10.1016/j.applanim.2016.01.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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18
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Proteomics of reproductive systems: Towards a molecular understanding of postmating, prezygotic reproductive barriers. J Proteomics 2016; 135:26-37. [DOI: 10.1016/j.jprot.2015.10.015] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Revised: 09/28/2015] [Accepted: 10/11/2015] [Indexed: 11/20/2022]
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19
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Orbach DN, Marshall CD, Würsig B, Mesnick SL. Variation in Female Reproductive Tract Morphology of the Common Bottlenose Dolphin (Tursiops truncatus). Anat Rec (Hoboken) 2016; 299:520-37. [PMID: 26788790 DOI: 10.1002/ar.23318] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 11/08/2015] [Accepted: 12/13/2015] [Indexed: 11/07/2022]
Abstract
Cetaceans exhibit vaginal folds, unusual protrusions of the vaginal wall into the vaginal lumen. Inconsistent terminology and a lack of anatomical landmarks in the literature have hindered comparative studies of the form and function of vaginal folds. Our objectives are to: (1) develop a standardized measurement protocol for the reproductive tracts of female cetaceans, (2) assess variation in morphometrics within the common bottlenose dolphin (Tursiops truncatus), and (3) determine if vaginal muscle is skeletal, and therefore of somatic origin in this species. We selected 15 measurements to characterize female reproductive tracts and evaluated variability using fresh or frozen-thawed specimens from southeastern USA representing a range of sexual maturity states and reproductive states (n = 18 specimens). Presence of skeletal muscle and variation in the density of muscle banding were assessed using 90 histological samples (n = 5 specimens). Analyses of the gross morphological data revealed that the dolphins generally had one large vaginal fold that bisected the vaginal lumen. Vaginal morphology was similar for sexually mature and immature specimens and across reproductive states. The histological data revealed that the vaginal musculature consisted of smooth muscle, consistent with other mammals, leading us to conclude that vaginal contractions are likely under autonomic rather than somatic control. No differences were found in the density of smooth muscle banding among vaginal regions or sexual maturity states. Our systematic protocol lays the foundation for evaluating the function (e.g., sexual selection, natural selection) and evolution of vaginal folds.
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Affiliation(s)
- Dara N Orbach
- Department of Marine Biology, Texas A&M University at Galveston, Galveston, Texas
| | - Christopher D Marshall
- Department of Marine Biology, Texas A&M University at Galveston, Galveston, Texas.,Department of Wildlife and Fisheries Sciences, Texas A&M University, College Station, Texas
| | - Bernd Würsig
- Department of Marine Biology, Texas A&M University at Galveston, Galveston, Texas.,Department of Wildlife and Fisheries Sciences, Texas A&M University, College Station, Texas
| | - Sarah L Mesnick
- National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Southwest Fisheries Science Center, La Jolla, California
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20
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Friesen CR, Uhrig EJ, Mason RT, Brennan PLR. Female behaviour and the interaction of male and female genital traits mediate sperm transfer during mating. J Evol Biol 2016; 29:952-64. [PMID: 26809830 DOI: 10.1111/jeb.12836] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 01/18/2016] [Accepted: 01/19/2016] [Indexed: 02/04/2023]
Abstract
Natural selection and post-copulatory sexual selection, including sexual conflict, contribute to genital diversification. Fundamental first steps in understanding how these processes shape the evolution of specific genital traits are to determine their function experimentally and to understand the interactions between female and male genitalia during copulation. Our experimental manipulations of male and female genitalia in red-sided garter snakes (Thamnophis sirtalis parietalis) reveal that copulation duration and copulatory plug deposition, as well as total and oviductal/vaginal sperm counts, are influenced by the interaction between male and female genital traits and female behaviour during copulation. By mating females with anesthetized cloacae to males with spine-ablated hemipenes using a fully factorial design, we identified significant female-male copulatory trait interactions and found that females prevent sperm from entering their oviducts by contracting their vaginal pouch. Furthermore, these muscular contractions limit copulatory plug size, whereas the basal spine of the male hemipene aids in sperm and plug transfer. Our results are consistent with a role of sexual conflict in mating interactions and highlight the evolutionary importance of female resistance to reproductive outcomes.
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Affiliation(s)
- C R Friesen
- Department of Integrative Biology, Oregon State University, Corvallis, OR, USA.,School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, USA
| | - E J Uhrig
- Department of Integrative Biology, Oregon State University, Corvallis, OR, USA
| | - R T Mason
- Department of Integrative Biology, Oregon State University, Corvallis, OR, USA
| | - P L R Brennan
- Department of Biological Sciences, 104 Clapp Laboratory, Mount Holyoke College, South Hadley, MA, USA
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21
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Ala-Honkola O, Manier MK. Multiple mechanisms of cryptic female choice act on intraspecific male variation in Drosophila simulans. Behav Ecol Sociobiol 2016. [DOI: 10.1007/s00265-016-2069-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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22
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Wulff NC, Lehmann GUC. Function of male genital titillators in mating and spermatophore transfer in the tettigoniid bushcricketMetrioptera roeselii. Biol J Linn Soc Lond 2015. [DOI: 10.1111/bij.12661] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Nadja C. Wulff
- Department of Biology; Humboldt-University Berlin; Behavioral Physiology; Invalidenstrasse 43; 10115 Berlin Germany
| | - Gerlind U. C. Lehmann
- Department of Biology; Humboldt-University Berlin; Behavioral Physiology; Invalidenstrasse 43; 10115 Berlin Germany
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23
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Mokkonen M, Lindstedt C. The evolutionary ecology of deception. Biol Rev Camb Philos Soc 2015; 91:1020-1035. [PMID: 26118820 DOI: 10.1111/brv.12208] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 05/29/2015] [Accepted: 06/05/2015] [Indexed: 12/15/2022]
Abstract
Through dishonest signals or actions, individuals often misinform others to their own benefit. We review recent literature to explore the evolutionary and ecological conditions for deception to be more likely to evolve and be maintained. We identify four conditions: (1) high misinformation potential through perceptual constraints of perceiver; (2) costs and benefits of responding to deception; (3) asymmetric power relationships between individuals and (4) exploitation of common goods. We discuss behavioural and physiological mechanisms that form a deception continuum from secrecy to overt signals. Deceptive tactics usually succeed by being rare and are often evolving under co-evolutionary arms races, sometimes leading to the evolution of polymorphism. The degree of deception can also vary depending on the environmental conditions. Finally, we suggest a conceptual framework for studying deception and highlight important questions for future studies.
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Affiliation(s)
- Mikael Mokkonen
- Department of Biological and Environmental Science, University of Jyväskylä, PO Box 35, Jyväskylä 40014, Finland. .,Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.
| | - Carita Lindstedt
- Department of Biological and Environmental Science, Centre of Excellence in Biological Interactions, University of Jyväskylä, PO Box 35, Jyväskylä 40014, Finland
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24
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López-Sepulcre A, De Bona S, Valkonen JK, Umbers KD, Mappes J. Item Response Trees: a recommended method for analyzing categorical data in behavioral studies. Behav Ecol 2015. [DOI: 10.1093/beheco/arv091] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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25
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Fitzpatrick JL, Lüpold S. Sexual selection and the evolution of sperm quality. ACTA ACUST UNITED AC 2014; 20:1180-9. [DOI: 10.1093/molehr/gau067] [Citation(s) in RCA: 137] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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26
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Edward DA, Stockley P, Hosken DJ. Sexual conflict and sperm competition. Cold Spring Harb Perspect Biol 2014; 7:a017707. [PMID: 25301931 DOI: 10.1101/cshperspect.a017707] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Traits that increase a male's fertilization success during sperm competition can be harmful to females and therefore represent a source of sexual conflict. In this review, we consider the variety of male adaptations to sperm competition (MASC) that may give rise to sexual conflict-including mate guarding, prolonged copulations, the transfer of large numbers of sperm, and the manipulation of females through nonsperm components of the ejaculate. We then reflect on the fitness economics influencing the escalation of these sexual conflicts, considering the likelihood of females evolving traits to offset the negative effects of MASC when compared with the strong selection on males that lead to MASC. We conclude by discussing the potential evolutionary outcomes of sexual conflict arising from MASC, including the opportunities for females to mitigate conflict costs and the prospects for conflict resolution.
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Affiliation(s)
- Dominic A Edward
- Mammalian Behaviour and Evolution Group, Institute of Integrative Biology, University of Liverpool, Leahurst Campus, Neston CH64 7TE, United Kingdom
| | - Paula Stockley
- Mammalian Behaviour and Evolution Group, Institute of Integrative Biology, University of Liverpool, Leahurst Campus, Neston CH64 7TE, United Kingdom
| | - David J Hosken
- Centre for Ecology and Conservation, University of Exeter, Cornwall Campus, Penryn, Cornwall TR10 9FE, United Kingdom
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27
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Perez C, Granadeiro JP, Dias MP, Alonso H, Catry P. When males are more inclined to stay at home: insights into the partial migration of a pelagic seabird provided by geolocators and isotopes. Behav Ecol 2013. [DOI: 10.1093/beheco/art119] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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28
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Manier MK, Lüpold S, Belote JM, Starmer WT, Berben KS, Ala-Honkola O, Collins WF, Pitnick S. Postcopulatory sexual selection generates speciation phenotypes in Drosophila. Curr Biol 2013; 23:1853-62. [PMID: 24076241 DOI: 10.1016/j.cub.2013.07.086] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2013] [Revised: 07/31/2013] [Accepted: 07/31/2013] [Indexed: 01/29/2023]
Abstract
BACKGROUND Identifying traits that reproductively isolate species, and the selective forces underlying their divergence, is a central goal of evolutionary biology and speciation research. There is growing recognition that postcopulatory sexual selection, which can drive rapid diversification of interacting ejaculate and female reproductive tract traits that mediate sperm competition, may be an engine of speciation. Conspecific sperm precedence (CSP) is a taxonomically widespread form of reproductive isolation, but the selective causes and divergent traits responsible for CSP are poorly understood. RESULTS To test the hypothesis that postcopulatory sexual selection can generate reproductive isolation, we expressed GFP or RFP in sperm heads of recently diverged sister species, Drosophila simulans and D. mauritiana, to enable detailed resolution of species-specific sperm precedence mechanisms. Between-species divergence in sperm competition traits and mechanisms prompted six a priori predictions regarding mechanisms of CSP and degree of cross asymmetry in reproductive isolation. We resolved four distinct mechanisms of CSP that were highly consistent with predictions. These comprise interactions between multiple sex-specific traits, including two independent mechanisms by which females exert sophisticated control over sperm fate to favor the conspecific male. CONCLUSIONS Our results confirm that reproductive isolation can quickly arise from diversifying (allopatric) postcopulatory sexual selection. This experimental approach to "speciation phenotypes" illustrates how knowledge of sperm precedence mechanisms can be used to predict the mechanisms and extent of reproductive isolation between populations and species.
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Affiliation(s)
- Mollie K Manier
- Department of Biology, Syracuse University, Syracuse, NY 13244, USA
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29
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Løvlie H, Gillingham MAF, Worley K, Pizzari T, Richardson DS. Cryptic female choice favours sperm from major histocompatibility complex-dissimilar males. Proc Biol Sci 2013; 280:20131296. [PMID: 24004935 PMCID: PMC3768299 DOI: 10.1098/rspb.2013.1296] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Cryptic female choice may enable polyandrous females to avoid inbreeding or bias offspring variability at key loci after mating. However, the role of these genetic benefits in cryptic female choice remains poorly understood. Female red junglefowl, Gallus gallus, bias sperm use in favour of unrelated males. Here, we experimentally investigate whether this bias is driven by relatedness per se, or by similarity at the major histocompatibility complex (MHC), genes central to vertebrate acquired immunity, where polymorphism is critical to an individual's ability to combat pathogens. Through experimentally controlled natural matings, we confirm that selection against related males' sperm occurs within the female reproductive tract but demonstrate that this is more accurately predicted by MHC similarity: controlling for relatedness per se, more sperm reached the eggs when partners were MHC-dissimilar. Importantly, this effect appeared largely owing to similarity at a single MHC locus (class I minor). Further, the effect of MHC similarity was lost following artificial insemination, suggesting that male phenotypic cues might be required for females to select sperm differentially. These results indicate that postmating mechanisms that reduce inbreeding may do so as a consequence of more specific strategies of cryptic female choice promoting MHC diversity in offspring.
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Affiliation(s)
- Hanne Løvlie
- Department of Zoology, Edward Grey Institute, University of Oxford, Oxford OX1 3PS, UK.
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30
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Manier MK, Lüpold S, Pitnick S, Starmer WT. An analytical framework for estimating fertilization bias and the fertilization set from multiple sperm-storage organs. Am Nat 2013; 182:552-61. [PMID: 24021407 DOI: 10.1086/671782] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
How sperm from competing males are used to fertilize eggs is poorly understood yet has important implications for postcopulatory sexual selection. Sperm may be used in direct proportion to their numerical representation within the fertilization set or with a bias toward one male over another. Previous theoretical treatments have assumed a single sperm-storage organ, but many taxa possess multiple organs or store sperm within multiple regions of the reproductive tract. In Drosophila, females store sperm in two distinct storage organ types: the seminal receptacle (SR) and the paired spermathecae. Here, we expand previous "raffle" models to describe "fertilization bias" independently for sperm within the SR and the spermathecae and estimate the fertilization set based on the relative contribution of sperm from the different sperm-storage organ types. We apply this model to three closely related species to reveal rapid divergence in the fertilization set and the potential for female sperm choice.
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Affiliation(s)
- Mollie K Manier
- Department of Biology, Syracuse University, Syracuse, New York 13244
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31
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Manier MK, Belote JM, Berben KS, Lüpold S, Ala-Honkola O, Collins WF, Pitnick S. Rapid diversification of sperm precedence traits and processes among three sibling Drosophila species. Evolution 2013; 67:2348-62. [PMID: 23888856 DOI: 10.1111/evo.12117] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Accepted: 03/12/2013] [Indexed: 01/13/2023]
Abstract
Postcopulatory sexual selection is credited with driving rapid evolutionary diversification of reproductive traits and the formation of reproductive isolating barriers between species. This judgment, however, has largely been inferred rather than demonstrated due to general lack of knowledge about processes and traits underlying variation in competitive fertilization success. Here, we resolved processes determining sperm fate in twice-mated females, using transgenic Drosophila simulans and Drosophila mauritiana populations with fluorescently labeled sperm heads. Comparisons among these two species and Drosophila melanogaster revealed a shared motif in the mechanisms of sperm precedence, with postcopulatory sexual selection potentially occurring during any of the three discrete stages: (1) insemination; (2) sperm storage; and (3) sperm use for fertilization, and involving four distinct phenomena: (1) sperm transfer; (2) sperm displacement; (3) sperm ejection; and (4) sperm selection for fertilizations. Yet, underlying the qualitative similarities were significant quantitative differences in nearly every relevant character and process. We evaluate these species differences in light of concurrent investigations of within-population variation in competitive fertilization success and postmating/prezygotic reproductive isolation in hybrid matings between species to forge an understanding of the relationship between microevolutionary processes and macroevolutionary patterns as pertains to postcopulatory sexual selection in this group.
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Affiliation(s)
- Mollie K Manier
- Department of Biology, Syracuse University, Syracuse, New York 13244, USA
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32
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Rodriguez-Enriquez CL, Tadeo E, Rull J. Elucidating the function of ejaculate expulsion and consumption after copulation by female Euxesta bilimeki. Behav Ecol Sociobiol 2013. [DOI: 10.1007/s00265-013-1518-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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33
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Perry JC, Sirot L, Wigby S. The seminal symphony: how to compose an ejaculate. Trends Ecol Evol 2013; 28:414-22. [PMID: 23582755 DOI: 10.1016/j.tree.2013.03.005] [Citation(s) in RCA: 204] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Revised: 02/17/2013] [Accepted: 03/13/2013] [Indexed: 02/06/2023]
Abstract
Ejaculates are fundamental to fitness in sexually reproducing animals: males gain all their direct fitness via the ejaculate and females require ejaculates to reproduce. Both sperm and non-sperm components of the ejaculate (including parasperm, seminal proteins, water, and macromolecules) play vital roles in postcopulatory sexual selection and conflict, processes that can potentially drive rapid evolutionary change and reproductive isolation. Here, we assess the increasing evidence that considering ejaculate composition as a whole (and potential trade-offs among ejaculate components) has important consequences for predictions about male reproductive investment and female responses to ejaculates. We review current theory and empirical work, and detail how social and environmental effects on ejaculate composition have potentially far-reaching fitness consequences for both sexes.
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Affiliation(s)
- Jennifer C Perry
- Edward Grey Institute, Department of Zoology, University of Oxford, Oxford, OX1 3PS, UK.
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34
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Nakagawa S, Schielzeth H. A general and simple method for obtainingR2from generalized linear mixed-effects models. Methods Ecol Evol 2012. [DOI: 10.1111/j.2041-210x.2012.00261.x] [Citation(s) in RCA: 6168] [Impact Index Per Article: 514.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Holger Schielzeth
- Department of Evolutionary Biology; Bielefeld University; Morgenbreede 45, 33615, Bielefeld; Germany
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35
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Noguera JC, Dean R, Isaksson C, Velando A, Pizzari T. Age-specific oxidative status and the expression of pre- and postcopulatory sexually selected traits in male red junglefowl, Gallus gallus. Ecol Evol 2012; 2:2155-67. [PMID: 23139875 PMCID: PMC3488667 DOI: 10.1002/ece3.300] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2012] [Revised: 05/21/2012] [Accepted: 05/23/2012] [Indexed: 01/28/2023] Open
Abstract
Oxidative stress is emerging as a key factor underpinning life history and the expression of sexually selected traits. Resolving the role of oxidative stress in life history and sexual selection requires a pluralistic approach, which investigates how age affects the relationship between oxidative status (i.e., antioxidants and oxidative damage) and the multiple traits contributing to variation in reproductive success. Here, we investigate the relationship between oxidative status and the expression of multiple sexually selected traits in two-age classes of male red junglefowl, Gallus gallus, a species which displays marked male reproductive senescence. We found that, irrespective of male age, both male social status and comb size were strongly associated with plasma oxidative status, and there was a nonsignificant tendency for sperm motility to be associated with seminal oxidative status. Importantly, however, patterns of plasma and seminal antioxidant levels differed markedly in young and old males. While seminal antioxidants increased with plasma antioxidants in young males, the level of seminal antioxidants remained low and was independent of plasma levels in old males. In addition, old males also accumulated more oxidative damage in their sperm DNA. These results suggest that antioxidant allocation across different reproductive traits and somatic maintenance might change drastically as males age, leading to age-specific patterns of antioxidant investment.
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Affiliation(s)
- Jose C Noguera
- Dpto. Ecoloxia e Bioloxía Animal, Edificio de Ciencias Experimentales, Universidad de Vigo 36310, Vigo, Pontevedra, Spain
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Collet J, Richardson DS, Worley K, Pizzari T. Sexual selection and the differential effect of polyandry. Proc Natl Acad Sci U S A 2012; 109:8641-5. [PMID: 22592795 PMCID: PMC3365207 DOI: 10.1073/pnas.1200219109] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In principle, widespread polyandry (female promiscuity) creates potential for sexual selection in males both before and after copulation. However, the way polyandry affects pre- and postcopulatory episodes of sexual selection remains little understood. Resolving this fundamental question has been difficult because it requires extensive information on mating behavior as well as paternity for the whole male population. Here we show that in replicate seminatural groups of red junglefowl, Gallus gallus, polyandry eroded variance in male mating success, which simultaneously weakened the overall intensity of sexual selection but increased the relative strength of postcopulatory episodes. We further illustrate the differential effect of polyandry on pre- and postcopulatory sexual selection by considering the case of male social status, a key determinant of male reproductive success in this species. In low-polyandry groups, however, status was strongly sexually selected before copulation because dominants mated with more females. In high-polyandry groups, sexual selection for status was weakened and largely restricted after copulation because dominants defended paternity by mating repeatedly with the same female. These results reveal polyandry as a potent and dynamic modulator of sexual selection episodes.
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Affiliation(s)
- Julie Collet
- Department of Zoology, Edward Grey Institute, University of Oxford, Oxford OX1 3PS, United Kingdom
| | - David S. Richardson
- Centre for Ecology, Evolution, and Conservation, School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom
| | - Kirsty Worley
- Department of Zoology, Edward Grey Institute, University of Oxford, Oxford OX1 3PS, United Kingdom
- Centre for Ecology, Evolution, and Conservation, School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom
| | - Tommaso Pizzari
- Department of Zoology, Edward Grey Institute, University of Oxford, Oxford OX1 3PS, United Kingdom
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37
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Johnson SL, Gemmell NJ. Are old males still good males and can females tell the difference? Do hidden advantages of mating with old males off-set costs related to fertility, or are we missing something else? Bioessays 2012; 34:609-19. [PMID: 22581618 DOI: 10.1002/bies.201100157] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Sperm function generally declines with male age. Paradoxically, females of many species still choose to mate with old males rather than young males. Females choosing old mates may suffer reduced fertilization rates and an increased incidence of birth defects in offspring, lowering fitness which may in turn lead to conflict between the sexes. This apparent paradox has generated much interest from theorists, but whether this paradox presents in nature remains equivocal. Empirical studies have found mixed support for both a decline in fertility with male age and age-based female mate preference. Here, we examine recent evidence for this paradox, identify confounding variables, highlight areas that deserve further investigation, and suggest avenues for future research.
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Affiliation(s)
- Sheri L Johnson
- Centre for Reproduction and Genomics, Department of Anatomy, University of Otago, Dunedin, New Zealand.
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