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Burns-Dunn S, Mortys T, House CM, Mitchell C, Duffield KR, Foquet B, Sadd BM, Sakaluk SK, Hunt J. Sexually antagonistic coevolution of the male nuptial gift and female feeding behaviour in decorated crickets. Proc Biol Sci 2024; 291:20240804. [PMID: 38955230 DOI: 10.1098/rspb.2024.0804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 06/11/2024] [Indexed: 07/04/2024] Open
Abstract
The evolution of nuptial gifts has traditionally been considered a harmonious affair, providing benefits to both mating partners. There is growing evidence, however, that receiving a nuptial gift can be actively detrimental to the female. In decorated crickets (Gryllodes sigillatus), males produce a gelatinous spermatophylax that enhances sperm transfer but provides little nutritional benefit and hinders female post-copulatory mate choice. Here, we examine the sexually antagonistic coevolution of the spermatophylax and the female feeding response to this gift in G. sigillatus maintained in experimental populations with either a male-biased or female-biased adult sex ratio. After 25 generations, males evolving in male-biased populations produced heavier spermatophylaxes with a more manipulative combination of free amino acids than those evolving in female-biased populations. Moreover, when the spermatophylax originated from the same selection regime, females evolving in male-biased populations always had shorter feeding durations than those evolving in female-biased populations, indicating the evolution of greater resistance. Across populations, female feeding duration increased with the mass and manipulative combination of free amino acids in the spermatophylax, suggesting sexually antagonistic coevolution. Collectively, our work demonstrates a key role for interlocus sexual conflict and sexually antagonistic coevolution in the mating system of G. sigillatus.
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Affiliation(s)
- Samuel Burns-Dunn
- School of Science, Western Sydney University, Hawkesbury Campus, Richmond, NSW 2753, Australia
| | - Tassie Mortys
- School of Science, Western Sydney University, Hawkesbury Campus, Richmond, NSW 2753, Australia
| | - Clarissa M House
- School of Science, Western Sydney University, Hawkesbury Campus, Richmond, NSW 2753, Australia
| | - Christopher Mitchell
- Centre for Ecology & Conservation, School of Biosciences, University of Exeter, Cornwall Campus, Penryn TR10 9EZ, UK
| | - Kristin R Duffield
- Crop BioProtection Research Unit, Agricultural Research Services, United States Department of Agriculture, National Centre for Agricultural Utilization Research, Peoria, IL, USA
| | - Bert Foquet
- School of Biological Sciences, Illinois State University, Normal, IL 61790-4120, USA
| | - Ben M Sadd
- School of Biological Sciences, Illinois State University, Normal, IL 61790-4120, USA
| | - Scott K Sakaluk
- School of Biological Sciences, Illinois State University, Normal, IL 61790-4120, USA
| | - John Hunt
- School of Science, Western Sydney University, Hawkesbury Campus, Richmond, NSW 2753, Australia
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2
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Londoño-Nieto C, García-Roa R, Garcia-Co C, González P, Carazo P. Thermal phenotypic plasticity of pre- and post-copulatory male harm buffers sexual conflict in wild Drosophila melanogaster. eLife 2023; 12:e84759. [PMID: 37102499 PMCID: PMC10191624 DOI: 10.7554/elife.84759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 04/26/2023] [Indexed: 04/28/2023] Open
Abstract
Strong sexual selection frequently leads to sexual conflict and ensuing male harm, whereby males increase their reproductive success at the expense of harming females. Male harm is a widespread evolutionary phenomenon with a strong bearing on population viability. Thus, understanding how it unfolds in the wild is a current priority. Here, we sampled a wild Drosophila melanogaster population and studied male harm across the normal range of temperatures under which it reproduces optimally in nature by comparing female lifetime reproductive success and underlying male harm mechanisms under monogamy (i.e. low male competition/harm) vs. polyandry (i.e. high male competition/harm). While females had equal lifetime reproductive success across temperatures under monogamy, polyandry resulted in a maximum decrease of female fitness at 24°C (35%), reducing its impact at both 20°C (22%), and 28°C (10%). Furthermore, female fitness components and pre- (i.e. harassment) and post-copulatory (i.e. ejaculate toxicity) mechanisms of male harm were asymmetrically affected by temperature. At 20°C, male harassment of females was reduced, and polyandry accelerated female actuarial aging. In contrast, the effect of mating on female receptivity (a component of ejaculate toxicity) was affected at 28°C, where the mating costs for females decreased and polyandry mostly resulted in accelerated reproductive aging. We thus show that, across a natural thermal range, sexual conflict processes and their effects on female fitness components are plastic and complex. As a result, the net effect of male harm on overall population viability is likely to be lower than previously surmised. We discuss how such plasticity may affect selection, adaptation and, ultimately, evolutionary rescue under a warming climate.
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Affiliation(s)
- Claudia Londoño-Nieto
- Ethology Lab, Cavanilles Institute of Biodiversity and Evolutionary Biology, University of ValenciaValenciaSpain
| | - Roberto García-Roa
- Ethology Lab, Cavanilles Institute of Biodiversity and Evolutionary Biology, University of ValenciaValenciaSpain
- Department of Biology, Lund UniversityLundSweden
| | - Clara Garcia-Co
- Ethology Lab, Cavanilles Institute of Biodiversity and Evolutionary Biology, University of ValenciaValenciaSpain
| | - Paula González
- Ethology Lab, Cavanilles Institute of Biodiversity and Evolutionary Biology, University of ValenciaValenciaSpain
| | - Pau Carazo
- Ethology Lab, Cavanilles Institute of Biodiversity and Evolutionary Biology, University of ValenciaValenciaSpain
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3
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Kappeler PM, Benhaiem S, Fichtel C, Fromhage L, Höner OP, Jennions MD, Kaiser S, Krüger O, Schneider JM, Tuni C, van Schaik J, Goymann W. Sex roles and sex ratios in animals. Biol Rev Camb Philos Soc 2023; 98:462-480. [PMID: 36307924 DOI: 10.1111/brv.12915] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 10/12/2022] [Accepted: 10/14/2022] [Indexed: 11/29/2022]
Abstract
In species with separate sexes, females and males often differ in their morphology, physiology and behaviour. Such sex-specific traits are functionally linked to variation in reproductive competition, mate choice and parental care, which have all been linked to sex roles. At the 150th anniversary of Darwin's theory on sexual selection, the question of why patterns of sex roles vary within and across species remains a key topic in behavioural and evolutionary ecology. New theoretical, experimental and comparative evidence suggests that variation in the adult sex ratio (ASR) is a key driver of variation in sex roles. Here, we first define and discuss the historical emergence of the sex role concept, including recent criticisms and rebuttals. Second, we review the various sex ratios with a focus on ASR, and explore its theoretical links to sex roles. Third, we explore the causes, and especially the consequences, of biased ASRs, focusing on the results of correlational and experimental studies of the effect of ASR variation on mate choice, sexual conflict, parental care and mating systems, social behaviour, hormone physiology and fitness. We present evidence that animals in diverse societies are sensitive to variation in local ASR, even on short timescales, and propose explanations for conflicting results. We conclude with an overview of open questions in this field integrating demography, life history and behaviour.
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Affiliation(s)
- Peter M Kappeler
- Behavioral Ecology and Sociobiology Unit, German Primate Center - Leibniz Institute of Primatology, Kellnerweg 4, 37077, Göttingen, Germany
- Department of Sociobiology/Anthropology, University of Göttingen, Kellnerweg 6, 37077, Göttingen, Germany
| | - Sarah Benhaiem
- Department of Ecological Dynamics, Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, D-10315, Berlin, Germany
| | - Claudia Fichtel
- Behavioral Ecology and Sociobiology Unit, German Primate Center - Leibniz Institute of Primatology, Kellnerweg 4, 37077, Göttingen, Germany
| | - Lutz Fromhage
- Department of Biological and Environmental Science, Ambiotica, University of Jyväskylä, PO Box 35, 40014, Jyväskylä, Finland
| | - Oliver P Höner
- Department of Evolutionary Ecology, Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, D-10315, Berlin, Germany
| | - Michael D Jennions
- Division of Ecology & Evolution, Research School of Biology, ANU College of Science, The Australian National University, RN Robertson Building, 46 Sullivans Creek Road, Canberra, ACT, 2600, Australia
| | - Sylvia Kaiser
- Department of Behavioural Biology, University of Münster, Badestr. 13, 48149, Münster, Germany
| | - Oliver Krüger
- Department of Animal Behavior, Bielefeld University, Morgenbreede 45, 33615, Bielefeld, Germany
| | - Jutta M Schneider
- Department of Biology, Institute of Zoology, Universität Hamburg, Martin-Luther-King Platz 3, 20146, Hamburg, Germany
| | - Cristina Tuni
- Department of Biology II, Ludwig Maximilians University of Munich, Großhaderner Str 2, 82152, Planegg-Martinsried, Germany
| | - Jaap van Schaik
- Applied Zoology and Nature Conservation, University of Greifswald, Loitzer Str. 26, 17489, Greifswald, Germany
| | - Wolfgang Goymann
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, Eberhard-Gwinner-Str. 6a, D-82319, Seewiesen, Germany
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4
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Kyogoku D, Dobata S, Takashima R, Sota T. Female-limited responses in remating rate and mating duration in the experimental evolution of a beetle Callosobruchus chinensis. J Evol Biol 2023; 36:309-314. [PMID: 36514853 DOI: 10.1111/jeb.14141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 11/09/2022] [Accepted: 11/16/2022] [Indexed: 12/15/2022]
Abstract
Mating rate optima often differ between the sexes: males may increase their fitness by multiple mating, but for females multiple mating confers little benefit and can often be costly (especially in taxa without nuptial gifts or mala parental care). Sexually antagonistic evolution is thus expected in traits related to mating rates under sexual selection. This prediction has been tested by multiple studies that applied experimental evolution technique, which is a powerful tool to directly examine the evolutionary consequences of selection. Yet, the results so far only partly support the prediction. Here, we provide another example of experimental evolution of sexual selection, by applying it for the first time to the mating behaviour of a seed beetle Callsorobruchus chinensis. We found a lower remating rate in polygamy-line females than in monogamy-line (i.e. no sexual selection) females after 21 generations of selection. Polygamy-line females also showed a longer duration of first mating than monogamy-line females. We found no effect of male evolutionary lines on the remating rate or first mating duration. Though not consistent with the original prediction, the current and previous studies collectively suggest that the observed female-limited responses may be a norm, which is also consistent with the conceptual advances in the last two decades of the advantages and limitations of experimental evolution technique.
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Affiliation(s)
- Daisuke Kyogoku
- Department of Zoology, Graduate School of Science, Kyoto University, Kyoto, Japan
| | - Shigeto Dobata
- Laboratory of Insect Ecology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Rui Takashima
- Laboratory of Insect Ecology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Teiji Sota
- Department of Zoology, Graduate School of Science, Kyoto University, Kyoto, Japan
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5
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Park YH, Shin D, Han CS. Polyandrous females but not monogamous females vary in reproductive ageing patterns in the bean bug Riptortus pedestris. BMC Ecol Evol 2022; 22:115. [PMID: 36217117 PMCID: PMC9549660 DOI: 10.1186/s12862-022-02070-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 09/27/2022] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND In general, reproductive performance exhibits nonlinear changes with age. Specifically, reproductive performance increases early in life, reaches a peak, and then declines later in life. Reproductive ageing patterns can also differ among individuals if they are influenced by individual-specific strategies of resource allocation between early-life reproduction and maintenance. In addition, the social environment, such as the number of available mates, can influence individual-specific resource allocation strategies and consequently alter the extent of individual differences in reproductive ageing patterns. That is, females that interact with more partners are expected to vary their copulation frequency, adopt a more flexible reproductive strategy and exhibit greater individual differences in reproductive ageing patterns. METHODS In this study, we evaluated the effect of mating with multiple males on both group- and individual-level reproductive ageing patterns in females of the bean bug Riptortus pedestris by ensuring that females experienced monogamous (one female with one male) or polyandrous conditions (one female with two males). RESULTS We found that group-level reproductive ageing patterns did not differ between monogamy-treatment and polyandry-treatment females. However, polyandry-treatment females exhibited among-individual variation in reproductive ageing patterns, while monogamy-treatment females did not. CONCLUSION Our findings provide the first empirical evidence regarding the influence of the social environment on individual variation in reproductive ageing patterns. We further suggest that the number of potential mates influences group- and individual-level reproductive ageing patterns, depending on which sex controls mating. We encourage future studies to consider interactions between species-specific mating systems and the social environment when evaluating group- and individual-level reproductive ageing patterns.
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Affiliation(s)
- Yi Hang Park
- grid.289247.20000 0001 2171 7818Department of Biology, Kyung Hee University, Seoul, Korea
| | - Donggyun Shin
- grid.289247.20000 0001 2171 7818Department of Biology, Kyung Hee University, Seoul, Korea
| | - Chang S. Han
- grid.289247.20000 0001 2171 7818Department of Biology, Kyung Hee University, Seoul, Korea
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6
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Lund-Hansen KK, Kutzer MAM, Armitage SAO, Gornard S, Keilani H, Abbott JK. Female-limited X chromosome evolution reveals that lifespan is mainly modulated by interlocus rather than intralocus sexual conflict. Behav Ecol Sociobiol 2022; 76:120. [PMID: 35991525 PMCID: PMC9385781 DOI: 10.1007/s00265-022-03231-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Revised: 07/29/2022] [Accepted: 08/08/2022] [Indexed: 11/21/2022]
Abstract
Abstract Sexual dimorphism in somatic investment may be shaped by two distinct forms of sexual conflict; under intralocus sexual conflict (IASC), males and females have different optimal levels of somatic investment but are constrained from reaching their respective optima by their shared genome, while under interlocus sexual conflict (IRSC), males and females have different optimal sexual strategies, which could have direct or indirect effects on levels of somatic investment. We investigated effects of IASC and IRSC on two aspects of somatic investment, immune defence strategies and longevity, using previously established female-limited experimental evolution lines in Drosophila melanogaster. We found little evidence for any effect of either type of sexual conflict on investment in the immune defence resistance or tolerance. Nor did we find convincing evidence that longevity is subject to IASC in this species. However, we did find evidence that increased female control over mating rate had important and opposite effects on longevity between the sexes. Specifically, females that had adapted to high levels of female control over mating had a longer lifespan when kept in mixed-sex groups, while males had shorter longevity, perhaps due to increased investment in post-copulatory sexual selection. These novel results show that female control over mating rates may have important and unexpected effects on patterns of somatic investment. Significance statement Sexual conflict occurs between the two sexes over numerous life history traits, and it is complex to disentangle how these traits interact and affect each other. Here we use a long-term evolution experiment to investigate sexual dimorphism in somatic maintenance. We found no effect of feminising the X chromosome on female immune defence. However, we did find that increased female control over mating rate resulted in longer female lifespan, but reduced male lifespan, and that these effects were dependent on social context (isolated or in mixed-sex groups). Unlike previous studies on the effect of sexual conflict on longevity, our experiment did not manipulate environmental conditions nor the adult sex ratio, which is likely to reduce both pre- and post-copulatory sexual selection. Supplementary Information The online version contains supplementary material available at 10.1007/s00265-022-03231-4.
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7
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Evolution of reduced mate harming tendency of males in Drosophila melanogaster populations selected for faster life history. Behav Ecol Sociobiol 2022. [DOI: 10.1007/s00265-022-03187-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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8
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Sepil I, Perry JC, Dore A, Chapman T, Wigby S. Experimental evolution under varying sex ratio and nutrient availability modulates male mating success in Drosophila melanogaster. Biol Lett 2022; 18:20210652. [PMID: 35642384 PMCID: PMC9156920 DOI: 10.1098/rsbl.2021.0652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Biased population sex ratios can alter optimal male mating strategies, and allocation to reproductive traits depends on nutrient availability. However, there is little information on how nutrition interacts with sex ratio to influence the evolution of pre-copulatory and post-copulatory traits separately. To address this omission, we test how male mating success and reproductive investment evolve under varying sex ratios and adult diet in Drosophila melanogaster, using experimental evolution. We found that sex ratio and nutrient availability interacted to determine male pre-copulatory performance. Males from female-biased populations were slow to mate when they evolved under protein restriction. By contrast, we found direct and non-interacting effects of sex ratio and nutrient availability on post-copulatory success. Males that evolved under protein restriction were relatively poor at suppressing female remating. Males that evolved under equal sex ratios fathered more offspring and were better at supressing female remating, relative to males from male-biased or female-biased populations. These results support the idea that sex ratios and nutrition interact to determine the evolution of pre-copulatory mating traits, but independently influence the evolution of post-copulatory traits.
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Affiliation(s)
- Irem Sepil
- Department of Zoology, University of Oxford, 11a Mansfield Road, Oxford OX1 3SZ, UK
| | - Jennifer C Perry
- Department of Zoology, University of Oxford, 11a Mansfield Road, Oxford OX1 3SZ, UK.,School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Alice Dore
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Tracey Chapman
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Stuart Wigby
- Department of Zoology, University of Oxford, 11a Mansfield Road, Oxford OX1 3SZ, UK.,Department of Evolution, Ecology, and Behaviour, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK
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9
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Canal D, Garamszegi LZ, Rodriguez‐Exposito E, Garcia‐Gonzalez F. Experimental evolution reveals differential evolutionary trajectories in male and female activity levels in response to sexual selection and metapopulation structure. Evolution 2022; 76:1347-1359. [PMID: 35483712 PMCID: PMC9320835 DOI: 10.1111/evo.14499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 11/23/2021] [Accepted: 12/15/2021] [Indexed: 01/21/2023]
Abstract
Behavior is central to interactions with the environment and thus has significant consequences for individual fitness. Sexual selection and demographic processes have been shown to independently shape behavioral evolution. Although some studies have tested the simultaneous effects of these forces, no studies have investigated their interplay in behavioral evolution. We applied experimental evolution in the seed beetle Callosobruchus maculatus to investigate, for the first time, the interactive effects of sexual selection intensity (high [polygamy] vs. minimal [enforced monogamy]) and metapopulation structure (yes/no) on the evolution of movement activity, a crucial behavior involved in multiples functions (e.g., dispersal, predator avoidance, or resource acquisition) and thus, closely related to fitness. We found that the interactive effects of the selection regimes did not affect individual activity, which was assayed under two different environments (absence vs. presence of conspecific cues from both sexes). However, contrasting selection regimes led to sex- and context-dependent divergence in activity. The relaxation of sexual selection favored an increase in female, but not male, movement activity that was consistent between environmental contexts. In contrast, selection associated with the presence/absence of metapopulation structure led to context-dependent responses only in male activity. In environments containing cues from conspecifics, males from selection lines under population subdivision showed increased levels of activity compared to those assayed in an environment devoid of conspecifics cues, whereas the opposite was true for males from panmictic lines. These results underscore that both the effects of sexual selection and population spatial structure may be crucial in shaping sex-specific behavioral evolution.
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Affiliation(s)
- David Canal
- Institute of Ecology and BotanyCentre for Ecological ResearchVácrátótH‐2163Hungary,Estación Biológica de Doñana‐CSICSeville41092Spain
| | - László Zsolt Garamszegi
- Institute of Ecology and BotanyCentre for Ecological ResearchVácrátótH‐2163Hungary,Estación Biológica de Doñana‐CSICSeville41092Spain,MTA‐ELTE, Theoretical Biology and Evolutionary Ecology Research Group, Department of Plant Systematics, Ecology and Theoretical BiologyEötvös Loránd UniversityBudapestH‐1053Hungary
| | | | - Francisco Garcia‐Gonzalez
- Estación Biológica de Doñana‐CSICSeville41092Spain,Centre for Evolutionary Biology, School of Biological SciencesUniversity of Western AustraliaCrawleyWA6009Australia
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10
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Colpitts J, Jarvis WMC, Agrawal AF, Rundle HD. Quantifying male harm and its divergence. Evolution 2022; 76:829-836. [PMID: 35276016 DOI: 10.1111/evo.14471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 01/24/2022] [Accepted: 02/04/2022] [Indexed: 01/21/2023]
Abstract
Male harm arises when traits that increase reproductive success in competition with other males also harm females as a side effect. The extent of harm depends on male and female phenotypes, both of which can diverge between populations. Within a population, harm is inferred when increased exposure to males reduces female fitness, but studies of the divergence of male harm rarely manipulate male exposure. Here, we quantify male harm and compare its magnitude between two lab populations of Drosophila serrata that were derived from a common ancestor 7 years earlier and subsequently held under conditions that minimized environmental differences. We manipulated female exposure to males in a factorial design involving all four combinations of males and females from these populations, providing insight into divergence in both sexes. Our results reveal substantial harm to females and provide stronger evidence of divergence in males than in females. Using these and other published data, we discuss conceptual issues surrounding the quantification and comparison of harm that arise because it involves a comparison of multiple quantities (e.g., female fitness under varying male exposure), and we demonstrate the increased insight that is gained by manipulating male exposure to quantify these quantities.
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Affiliation(s)
- Julie Colpitts
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada.,Current address: Department of Biology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Will M C Jarvis
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Aneil F Agrawal
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada
| | - Howard D Rundle
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
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11
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Marquez‐Rosado A, Garcia‐Co C, Londoño‐Nieto C, Carazo P. No evidence that relatedness or familiarity modulates male harm in Drosophila melanogaster flies from a wild population. Ecol Evol 2022; 12:e8803. [PMID: 35432938 PMCID: PMC8995922 DOI: 10.1002/ece3.8803] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 02/07/2022] [Accepted: 02/14/2022] [Indexed: 01/06/2023] Open
Abstract
Sexual selection frequently promotes the evolution of aggressive behaviors that help males compete against their rivals, but which may harm females and hamper their fitness. Kin selection theory predicts that optimal male-male competition levels can be reduced when competitors are more genetically related to each other than to the population average, contributing to resolve this sexual conflict. Work in Drosophila melanogaster has spearheaded empirical tests of this idea, but studies so far have been conducted in laboratory-adapted populations in homogeneous rearing environments that may hamper kin recognition, and used highly skewed sex ratios that may fail to reflect average natural conditions. Here, we performed a fully factorial design with the aim of exploring how rearing environment (i.e., familiarity) and relatedness affect male-male aggression, male harassment, and overall male harm levels in flies from a wild population of Drosophila melanogaster, under more natural conditions. Namely, we (a) manipulated relatedness and familiarity so that larvae reared apart were raised in different environments, as is common in the wild, and (b) studied the effects of relatedness and familiarity under average levels of male-male competition in the field. We show that, contrary to previous findings, groups of unrelated-unfamiliar males were as likely to fight with each other and harass females than related-familiar males and that overall levels of male harm to females were similar across treatments. Our results suggest that the role of kin selection in modulating sexual conflict is yet unclear in Drosophila melanogaster, and call for further studies that focus on natural populations and realistic socio-sexual and ecological environments.
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Affiliation(s)
- Ana Marquez‐Rosado
- Ethology LabCavanilles Institute of Biodiversity and Evolutionary BiologyUniversity of ValenciaValenciaSpain
| | - Clara Garcia‐Co
- Ethology LabCavanilles Institute of Biodiversity and Evolutionary BiologyUniversity of ValenciaValenciaSpain
| | - Claudia Londoño‐Nieto
- Ethology LabCavanilles Institute of Biodiversity and Evolutionary BiologyUniversity of ValenciaValenciaSpain
| | - Pau Carazo
- Ethology LabCavanilles Institute of Biodiversity and Evolutionary BiologyUniversity of ValenciaValenciaSpain
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12
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Geeta Arun M, Chechi TS, Meena R, Bhosle SD, Srishti, Prasad NG. Investigating the interaction between inter-locus and intra-locus sexual conflict using hemiclonal analysis in Drosophila melanogaster. BMC Ecol Evol 2022; 22:38. [PMID: 35346023 PMCID: PMC8962633 DOI: 10.1186/s12862-022-01992-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 03/15/2022] [Indexed: 12/02/2022] Open
Abstract
Background Divergence in the evolutionary interests of males and females leads to sexual conflict. Traditionally, sexual conflict has been classified into two types: inter-locus sexual conflict (IeSC) and intra-locus sexual conflict (IaSC). IeSC is modeled as a conflict over outcomes of intersexual reproductive interactions mediated by loci that are sex-limited in their effects. IaSC is thought to be a product of selection acting in opposite directions in males and females on traits with a common underlying genetic basis. While in their canonical formalisms IaSC and IeSC are mutually exclusive, there is growing support for the idea that the two may interact. Empirical evidence for such interactions, however, is limited. Results Here, we investigated the interaction between IeSC and IaSC in Drosophila melanogaster. Using hemiclonal analysis, we sampled 39 hemigenomes from a laboratory-adapted population of D. melanogaster. We measured the contribution of each hemigenome to adult male and female fitness at three different intensities of IeSC, obtained by varying the operational sex ratio. Subsequently, we estimated the intensity of IaSC at each sex ratio by calculating the intersexual genetic correlation (rw,g,mf) for fitness and the proportion of sexually antagonistic fitness-variation. We found that the intersexual genetic correlation for fitness was positive at all three sex ratios. Additionally, at male biased and equal sex ratios the rw,g,mf was higher, and the proportion of sexually antagonistic fitness variation lower, relative to the female biased sex ratio, although this trend was not statistically significant. Conclusion Our results indicate a statistically non-significant trend suggesting that increasing the strength of IeSC ameliorates IaSC in the population. Supplementary Information The online version contains supplementary material available at 10.1186/s12862-022-01992-0.
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Affiliation(s)
- Manas Geeta Arun
- Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Sector 81, SAS Nagar, Mohali, Punjab, 140306, India
| | - Tejinder Singh Chechi
- Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Sector 81, SAS Nagar, Mohali, Punjab, 140306, India
| | - Rakesh Meena
- Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Sector 81, SAS Nagar, Mohali, Punjab, 140306, India
| | - Shradha Dattaraya Bhosle
- Department of Biochemistry, Dr. Babasaheb Ambedkar Marathwada University, University Campus, Jaisigpura, Aurangabad, Maharashtra, 431004, India
| | - Srishti
- Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Sector 81, SAS Nagar, Mohali, Punjab, 140306, India
| | - Nagaraj Guru Prasad
- Department of Biological Sciences, Indian Institute of Science Education and Research Mohali, Sector 81, SAS Nagar, Mohali, Punjab, 140306, India.
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13
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Mital A, Sarangi M, Nandy B, Pandey N, Joshi A. Shorter effective lifespan in laboratory populations of D. melanogaster might reduce sexual selection. Behav Ecol Sociobiol 2022. [DOI: 10.1007/s00265-022-03158-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Abstract
The role of sexual selection in mediating levels of sexual conflict has been demonstrated in many experimental evolution studies on Drosophila spp. where competition among males for mating was the target of selection. Sexual selection has also been shown to affect the evolution of life-histories. However, the influence of divergent life-histories on reproductive strategies and, therefore, sexual selection and possibly sexual conflict has been less well studied. We examined D. melanogaster populations selected for a short development time and early age at reproduction for changes in reproductive behavior and traits that are proxies of sexual selection. We report a large reduction in reproductive competition experienced by the males of these populations, compared to ancestral populations that are not consciously selected for rapid development or early reproduction, potentially leading to reduced sexual selection. We show that rapidly developing and early reproducing populations have very low levels of mating in their lifetime (females are more or less monandrous), low courtship levels, shorter copulation duration, and longer time from eclosion to first mating, compared to the controls. These results are discussed in the context of the previously demonstrated reduction of inter-locus sexual conflict in these populations. We show that life-history strategies might have a large and significant impact on sexual selection, with each influencing the other and contributing to the complexities of adaptation.
Significance statement
Sexual conflict, often manifested as an arms-race between males and females trying to enhance their own reproductive success at some cost to the other, is of great evolutionary interest because it can maintain genetic variation in populations, prevent the independent optimization of male and female traits, and also promote speciation. Sexual selection, or variation in mating success, is well known to affect levels of sexual conflict. However, it is not so clear whether, and how, the regular evolution of life-histories also affects sexual selection. Here, we show that life-history evolution in fruit fly populations selected for traits not directly related to sexual conflict might, nevertheless, mediate the possible evolution of altered sexual conflict levels through effects on sexual selection. Populations that evolved to develop to adulthood fast, and reproduce relatively early in life, are shown to potentially experience less sexual selection, which can explain the low sexual conflict levels earlier observed in them.
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14
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Hopkins BR, Perry JC. The evolution of sex peptide: sexual conflict, cooperation, and coevolution. Biol Rev Camb Philos Soc 2022; 97:1426-1448. [PMID: 35249265 PMCID: PMC9256762 DOI: 10.1111/brv.12849] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 02/18/2022] [Accepted: 02/22/2022] [Indexed: 12/17/2022]
Abstract
A central paradigm in evolutionary biology is that the fundamental divergence in the fitness interests of the sexes (‘sexual conflict’) can lead to both the evolution of sex‐specific traits that reduce fitness for individuals of the opposite sex, and sexually antagonistic coevolution between the sexes. However, clear examples of traits that evolved in this way – where a single trait in one sex demonstrably depresses the fitness of members of the opposite sex, resulting in antagonistic coevolution – are rare. The Drosophila seminal protein ‘sex peptide’ (SP) is perhaps the most widely cited example of a trait that appears to harm females while benefitting males. Transferred in the ejaculate by males during mating, SP triggers profound and wide‐ranging changes in female behaviour and physiology. Early studies reported that the transfer of SP enhances male fitness while depressing female fitness, providing the foundations for the widespread view that SP has evolved to manipulate females for male benefit. Here, we argue that this view is (i) a simplification of a wider body of contradictory empirical research, (ii) narrow with respect to theory describing the origin and maintenance of sexually selected traits, and (iii) hard to reconcile with what we know of the evolutionary history of SP's effects on females. We begin by charting the history of thought regarding SP, both at proximate (its production, function, and mechanism of action) and ultimate (its fitness consequences and evolutionary history) levels, reviewing how studies of SP were central to the development of the field of sexual conflict. We describe a prevailing paradigm for SP's evolution: that SP originated and continues to evolve to manipulate females for male benefit. In contrast to this view, we argue on three grounds that the weight of evidence does not support the view that receipt of SP decreases female fitness: (i) results from studies of SP's impact on female fitness are mixed and more often neutral or positive, with fitness costs emerging only under nutritional extremes; (ii) whether costs from SP are appreciable in wild‐living populations remains untested; and (iii) recently described confounds in genetic manipulations of SP raise the possibility that measures of the costs and benefits of SP have been distorted. Beyond SP's fitness effects, comparative and genetic data are also difficult to square with the idea that females suffer fitness costs from SP. Instead, these data – from functional and evolutionary genetics and the neural circuitry of female responses to SP – suggest an evolutionary history involving the evolution of a dedicated SP‐sensing apparatus in the female reproductive tract that is likely to have evolved because it benefits females, rather than harms them. We end by exploring theory and evidence that SP benefits females by functioning as a signal of male quality or of sperm receipt and storage (or both). The expanded view of the evolution of SP that we outline recognises the context‐dependent and fluctuating roles played by both cooperative and antagonistic selection in the origin and maintenance of reproductive traits.
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Affiliation(s)
- Ben R. Hopkins
- Department of Evolution and Ecology University of California – Davis One Shields Avenue Davis CA 95616 U.S.A
| | - Jennifer C. Perry
- School of Biological Sciences University of East Anglia Norwich NR4 7TJ U.K
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15
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16
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Bath E, Buzzoni D, Ralph T, Wigby S, Sepil I. Male condition influences female post mating aggression and feeding in
Drosophila. Funct Ecol 2021. [DOI: 10.1111/1365-2435.13791] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Eleanor Bath
- Department of Zoology University of Oxford Oxford UK
| | - Daisy Buzzoni
- Department of Zoology University of Oxford Oxford UK
- University of Victoria Victoria BC Canada
| | - Toby Ralph
- Department of Zoology University of Oxford Oxford UK
| | - Stuart Wigby
- Department of Zoology University of Oxford Oxford UK
- Department of Evolution, Ecology, and Behaviour Institute of Infection, Veterinary & Ecological Sciences University of Liverpool Liverpool UK
| | - Irem Sepil
- Department of Zoology University of Oxford Oxford UK
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17
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Burke NW, Holwell GI. Male coercion and female injury in a sexually cannibalistic mantis. Biol Lett 2021; 17:20200811. [PMID: 33465328 DOI: 10.1098/rsbl.2020.0811] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Sexual conflict can generate coercive traits in males that enhance mating success at the expense of female fitness. Pre-copulatory sexual cannibalism-where females consume males without mating-typically favours cautious rather than coercive mating tactics, and few examples of the latter are known. Here, we show that males of the highly cannibalistic springbok mantis, Miomantis caffra, wrestle females during pre-mating interactions. We find that most initial contacts between males and females involve a violent struggle whereby each sex tries be the first to grasp hold of the other with their raptorial forelegs. When females win the struggle, they always cannibalize males. However, when males grasp females first, they dramatically increase the chance of mating. We also find striking evidence that, on some occasions, males wound females with their fore-tibial claws during struggles, resulting in haemolymph loss and scar tissue formation. Taken together, our results show how males can overcome the threat of cannibalism by coercively wrestling females. We argue that pre-copulatory injury in this species is likely to be a negative pleiotropic side-effect of coercive mating behaviour and foraging morphology.
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Affiliation(s)
- Nathan W Burke
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Gregory I Holwell
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
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18
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R Rodrigues L, Torralba Sáez M, Alpedrinha J, Lefèvre S, Brengues M, Magalhães S, Duncan AB. Consequences of population structure for sex allocation and sexual conflict. J Evol Biol 2021; 34:525-536. [PMID: 33314358 DOI: 10.1111/jeb.13755] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 11/07/2020] [Accepted: 11/30/2020] [Indexed: 11/29/2022]
Abstract
Both sex allocation and sexual conflict can be modulated by spatial structure. However, how the interplay between the type of dispersal and the scale of competition simultaneously affects these traits in sub-divided populations is rarely considered. We investigated sex allocation and sexual conflict evolution in meta-populations of the spider mite Tetranychus urticae evolving under budding (pairing females from the same patch) or random (pairing females from different patches) dispersal and either local (fixed sampling from each subpopulation) or global (sampling as a function of subpopulation productivity) competition. Females evolving under budding dispersal produced less female-biased offspring sex ratios than those from the random dispersal selection regimes, contradicting theoretical predictions. In contrast, the scale of competition did not strongly affect sex allocation. Offspring sex ratio and female fecundity were unaffected by the number of mates, but female fecundity was highest when their mates evolved under budding dispersal, suggesting these males inflict less harm than those evolving under random dispersal. This work highlights that population structure can impact the evolution of sex allocation and sexual conflict. Moreover, selection on either trait may reciprocally affect the evolution of the other, for example via effects on fecundity.
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Affiliation(s)
- Leonor R Rodrigues
- cE3c, Centre for Ecology, Evolution, and Environmental Changes, Faculty of Sciences, University of Lisbon, Lisboa, Portugal
| | - Mario Torralba Sáez
- Institut des Sciences de l'Évolution, Université de Montpellier, CNRS, IRD, EPHE, Montpellier, France
| | - João Alpedrinha
- cE3c, Centre for Ecology, Evolution, and Environmental Changes, Faculty of Sciences, University of Lisbon, Lisboa, Portugal
| | - Sophie Lefèvre
- Institut des Sciences de l'Évolution, Université de Montpellier, CNRS, IRD, EPHE, Montpellier, France
| | | | - Sara Magalhães
- cE3c, Centre for Ecology, Evolution, and Environmental Changes, Faculty of Sciences, University of Lisbon, Lisboa, Portugal
| | - Alison B Duncan
- Institut des Sciences de l'Évolution, Université de Montpellier, CNRS, IRD, EPHE, Montpellier, France
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19
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Filice DCS, Bhargava R, Dukas R. Female mating experience and genetic background independently influence male mating success in fruit flies. J Evol Biol 2020; 34:309-318. [PMID: 33128417 DOI: 10.1111/jeb.13729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 10/12/2020] [Accepted: 10/25/2020] [Indexed: 11/29/2022]
Abstract
When the reproductive interests of males and females conflict, males can evolve traits that are harmful to females, and females can coevolve traits to resist this harm. In the fruit fly, Drosophila melanogaster, there is genetic variation in female resistance traits, which can affect the pre- and post-mating success of males that try to mate with them. However, it is not clear to what extent the expression of these phenotypes can be modified by environmental factors such as sociosexual experience. Here, we tested how the genetic background of a female and her previous mating experience interact to affect the mating success of focal males. In the experience phase, we placed females from 28 distinct genetic backgrounds individually either with a single male (low conflict) or with three males (high conflict) for 48 hr. In the subsequent test phase, we measured the mating and post-mating fertilization success of focal males paired individually with each female. We found that focal males paired with females from the high-conflict treatment were less successful at mating, took longer to mate when they were successful, and had a lower proportion of paternity share. Furthermore, we identified significant female genetic variation associated with male mating success. These results indicate that female experience, along with intrinsic genetic factors, can independently influence different fitness components of her subsequent mates and has implications for our understanding of plastic female mating strategies and the evolution of sexually antagonistic traits in males and females.
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Affiliation(s)
- David C S Filice
- Department of Psychology, Neuroscience and Behaviour, McMaster University, Hamilton, ON, Canada
| | - Rajat Bhargava
- Department of Psychology, Neuroscience and Behaviour, McMaster University, Hamilton, ON, Canada
| | - Reuven Dukas
- Department of Psychology, Neuroscience and Behaviour, McMaster University, Hamilton, ON, Canada
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20
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Stångberg J, Immonen E, Moreno PP, Bolund E. Experimentally induced intrasexual mating competition and sex-specific evolution in female and male nematodes. J Evol Biol 2020; 33:1677-1688. [PMID: 32945028 PMCID: PMC7756511 DOI: 10.1111/jeb.13706] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 08/28/2020] [Accepted: 09/04/2020] [Indexed: 01/01/2023]
Abstract
Sexual dimorphism in life history traits and their trade-offs is widespread among sexually reproducing animals and is strongly influenced by the differences in reproductive strategies between the sexes. We investigated how intrasexual competition influenced specific life history traits, important to fitness and their trade-offs in the outcrossing nematode Caenorhabditis remanei. Here, we altered the strength of sex-specific selection through experimental evolution with increased potential for intrasexual competition by skewing the adult sex ratio towards either females or males (1:10 or 10:1) over 30 generations and subsequently measured the phenotypic response to selection in three traits related to fitness: body size, fecundity and tolerance to heat stress. We observed a greater evolutionary change in females than males for body size and peak fitness, suggesting that females may experience stronger net selection and potentially harbour higher amounts of standing genetic variance compared to males. Our study highlights the importance of investigating direct and indirect effects of intrasexual competition in both sexes in order to capture sex-specific responses and understand the evolution of sexual dimorphism in traits expressed by both sexes.
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Affiliation(s)
- Josefine Stångberg
- Department of Ecology and Genetics, Animal Ecology, Uppsala University, Uppsala, Sweden
| | - Elina Immonen
- Department of Ecology and Genetics, Evolutionary Biology, Uppsala University, Uppsala, Sweden
| | - Pilar Puimedon Moreno
- Department of Ecology and Genetics, Animal Ecology, Uppsala University, Uppsala, Sweden
| | - Elisabeth Bolund
- Department of Ecology and Genetics, Animal Ecology, Uppsala University, Uppsala, Sweden
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21
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Dore AA, Rostant WG, Bretman A, Chapman T. Plastic male mating behavior evolves in response to the competitive environment. Evolution 2020; 75:101-115. [PMID: 32844404 DOI: 10.1111/evo.14089] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 08/08/2020] [Accepted: 08/14/2020] [Indexed: 01/08/2023]
Abstract
Male reproductive phenotypes can evolve in response to the social and sexual environment. The expression of many such phenotypes may also be plastic within an individual's lifetime. For example, male Drosophila melanogaster show significantly extended mating duration following a period of exposure to conspecific male rivals. The costs and benefits of reproductive investment, and plasticity itself, can be shaped by the prevailing sociosexual environment and by resource availability. We investigated these ideas using experimental evolution lines of D. melanogaster evolving under three fixed sex ratios (high, medium, and low male-male competition) on either rich or poor adult diets. We found that males evolving in high-competition environments evolved longer mating durations overall. In addition, these males expressed a novel type of plastic behavioral response following exposure to rival males: they both significantly reduced and showed altered courtship delivery, and exhibited significantly longer mating latencies. Plasticity in male mating duration in response to rivals was maintained in all of the lines, suggesting that the costs of plasticity were minimal. None of the evolutionary responses tested were consistently affected by dietary resource regimes. Collectively, the results show that fixed behavioral changes and new augmentations to the repertoire of reproductive behaviors can evolve rapidly.
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Affiliation(s)
- Alice A Dore
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, United Kingdom
| | - Wayne G Rostant
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, United Kingdom
| | - Amanda Bretman
- Faculty of Biological Sciences, School of Biology, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Tracey Chapman
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, United Kingdom
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22
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García-Roa R, Garcia-Gonzalez F, Noble DWA, Carazo P. Temperature as a modulator of sexual selection. Biol Rev Camb Philos Soc 2020; 95:1607-1629. [PMID: 32691483 DOI: 10.1111/brv.12632] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 06/10/2020] [Accepted: 06/12/2020] [Indexed: 12/25/2022]
Abstract
A central question in ecology and evolution is to understand why sexual selection varies so much in strength across taxa; it has long been known that ecological factors are crucial to this. Temperature is a particularly salient abiotic ecological factor that modulates a wide range of physiological, morphological and behavioural traits, impacting individuals and populations at a global taxonomic scale. Furthermore, temperature exhibits substantial temporal variation (e.g. daily, seasonally and inter-seasonally), and hence for most species in the wild sexual selection will regularly unfold in a dynamic thermal environment. Unfortunately, studies have so far almost completely neglected the role of temperature as a modulator of sexual selection. Here, we outline the main pathways through which temperature can affect the intensity and form (i.e. mechanisms) of sexual selection, via: (i) direct effects on secondary sexual traits and preferences (i.e. trait variance, opportunity for selection and trait-fitness covariance), and (ii) indirect effects on key mating parameters, sex-specific reproductive costs/benefits, trade-offs, demography and correlated abiotic factors. Building upon this framework, we show that, by focusing exclusively on the first-order effects that environmental temperature has on traits linked with individual fitness and population viability, current global warming studies may be ignoring eco-evolutionary feedbacks mediated by sexual selection. Finally, we tested the general prediction that temperature modulates sexual selection by conducting a meta-analysis of available studies experimentally manipulating temperature and reporting effects on the variance of male/female reproductive success and/or traits under sexual selection. Our results show a clear association between temperature and sexual selection measures in both sexes. In short, we suggest that studying the feedback between temperature and sexual selection processes may be vital to developing a better understanding of variation in the strength of sexual selection in nature, and its consequences for population viability in response to environmental change (e.g. global warming).
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Affiliation(s)
- Roberto García-Roa
- Behaviour and Evolution, Ethology Lab, Cavanilles Institute of Biodiversity and Evolutionary Biology, University of Valencia, C/Catedrático José Beltrán 2, Paterna, Valencia, 46980, Spain
| | - Francisco Garcia-Gonzalez
- Doñana Biological Station, Spanish Research Council CSIC, c/Americo Vespucio, 26, Isla de la Cartuja, Sevilla, 41092, Spain.,Centre for Evolutionary Biology, School of Biological Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia
| | - Daniel W A Noble
- Ecology and Evolution Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales, 2052, Australia.,Division of Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, Australian Capital Territory, 2061, Australia
| | - Pau Carazo
- Behaviour and Evolution, Ethology Lab, Cavanilles Institute of Biodiversity and Evolutionary Biology, University of Valencia, C/Catedrático José Beltrán 2, Paterna, Valencia, 46980, Spain
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23
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McNamara KB, Sloan NS, Kershaw SE, van Lieshout E, Simmons LW. Males evolve to be more harmful under increased sexual conflict intensity in a seed beetle. Behav Ecol 2020. [DOI: 10.1093/beheco/arz186] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
One conspicuous manifestation of sexual conflict is traumatic mating, in which male genitalia damage the female during copulation. The penis of the seed beetle, Callosobruchus maculatus, is covered in spines that damage the female reproductive tract. Females kick males ostensibly to shorten these harmful copulations. How these iconic conflict behaviors coevolve in response to sexual conflict intensity can provide insight into the economics of these traits. We examined whether male harm and female resistance coevolved in response to elevated sexual conflict. We quantified copulation behavior and female reproductive tract damage of individuals from replicated populations evolving for 32 generations under low or high sexual conflict (female- and male-biased treatments, respectively). First, we permitted females ad libitum matings with males from either sex-ratio treatment, recording her tract damage and longevity. Second, we performed a full-factorial cross of matings by males and females from each of the replicate populations, recording mating and kicking duration and reproductive output. We found manipulation of sexual conflict intensity led to the evolution of male harmfulness, but not female resistance to harm. We also demonstrate that female kicking does not respond to sexual conflict intensity, suggesting it does not function to mitigate male harm in this species. Our findings demonstrate the complexities of behavioral and morphological coevolutionary responses to sexual conflict intensity in an important model species.
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Affiliation(s)
- Kathryn B McNamara
- Centre for Evolutionary Biology, School of Biological Sciences, University of Western Australia, Crawley, Australia
- School of BioSciences, University of Melbourne, BioSciences 4, Royal Parade, Parkville, Australia
| | - Nadia S Sloan
- Centre for Evolutionary Biology, School of Biological Sciences, University of Western Australia, Crawley, Australia
| | - Sian E Kershaw
- Centre for Evolutionary Biology, School of Biological Sciences, University of Western Australia, Crawley, Australia
| | - Emile van Lieshout
- Centre for Evolutionary Biology, School of Biological Sciences, University of Western Australia, Crawley, Australia
| | - Leigh W Simmons
- Centre for Evolutionary Biology, School of Biological Sciences, University of Western Australia, Crawley, Australia
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24
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Filice DCS, Bhargava R, Dukas R. Plasticity in male mating behavior modulates female life history in fruit flies. Evolution 2020; 74:365-376. [DOI: 10.1111/evo.13926] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 12/12/2019] [Accepted: 12/27/2019] [Indexed: 12/16/2022]
Affiliation(s)
- David C. S. Filice
- Department of Psychology, Neuroscience, and BehaviourMcMaster University Hamilton ON L8S 4K1 Canada
| | - Rajat Bhargava
- Department of Psychology, Neuroscience, and BehaviourMcMaster University Hamilton ON L8S 4K1 Canada
| | - Reuven Dukas
- Department of Psychology, Neuroscience, and BehaviourMcMaster University Hamilton ON L8S 4K1 Canada
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25
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Rostant WG, Mason JS, de Coriolis JC, Chapman T. Resource-dependent evolution of female resistance responses to sexual conflict. Evol Lett 2020; 4:54-64. [PMID: 32055411 PMCID: PMC7006461 DOI: 10.1002/evl3.153] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 12/02/2019] [Accepted: 12/06/2019] [Indexed: 01/31/2023] Open
Abstract
Sexual conflict can promote the evolution of dramatic reproductive adaptations as well as resistance to its potentially costly effects. Theory predicts that responses to sexual conflict will vary significantly with resource levels—when scant, responses should be constrained by trade‐offs, when abundant, they should not. However, this can be difficult to test because the evolutionary interests of the sexes align upon short‐term exposure to novel environments, swamping any selection due to sexual conflict. What is needed are investigations of populations that are well adapted to both differing levels of sexual conflict and resources. Here, we used this approach in a long‐term experimental evolution study to track the evolution of female resistance to sexual conflict in the fruit fly Drosophila melanogaster. In resource‐rich regimes, high‐conflict females evolved resistance to continual exposure to males. There was no difference in baseline survival, consistent with the idea that responses evolving under nutritional abundance experienced no trade‐offs with resistance. In the poor resource regimes, the ability of high‐conflict females to evolve resistance to males was severely compromised and they also showed lower baseline survival than low‐conflict females. This suggested high‐conflict females traded off somatic maintenance against any limited resistance they had evolved in response to sexual conflict. Overall, these findings provide experimental support for the hypothesis that evolutionary responses to sexual conflict are critically dependent upon resource levels.
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Affiliation(s)
- Wayne G Rostant
- School of Biological Sciences University of East Anglia Norwich NR4 7TJ United Kingdom
| | - Janet S Mason
- School of Biological Sciences University of East Anglia Norwich NR4 7TJ United Kingdom
| | | | - Tracey Chapman
- School of Biological Sciences University of East Anglia Norwich NR4 7TJ United Kingdom
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26
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Baxter CM, Yan JL, Dukas R. Genetic variation in sexual aggression and the factors that determine forced copulation success. Anim Behav 2019. [DOI: 10.1016/j.anbehav.2019.09.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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27
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Sutter A, Travers LM, Weedon M, Oku K, Price TAR, Wedell N. No selection for change in polyandry under experimental evolution. J Evol Biol 2019; 32:717-730. [PMID: 30970158 DOI: 10.1111/jeb.13476] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 04/04/2019] [Accepted: 04/05/2019] [Indexed: 12/11/2022]
Abstract
What drives mating system variation is a major question in evolutionary biology. Female multiple mating (polyandry) has diverse evolutionary consequences, and there are many potential benefits and costs of polyandry. However, our understanding of its evolution is biased towards studies enforcing monandry in polyandrous species. What drives and maintains variation in polyandry between individuals, genotypes, populations and species remains poorly understood. Genetic variation in polyandry may be actively maintained by selection, or arise by chance if polyandry is selectively neutral. In Drosophila pseudoobscura, there is genetic variation in polyandry between and within populations. We used isofemale lines to found replicate populations with high or low initial levels of polyandry and tracked polyandry under experimental evolution over seven generations. Polyandry remained relatively stable, reflecting the starting frequencies of the experimental populations. There were no clear fitness differences between high versus low polyandry genotypes, and there was no signature of balancing selection. We confirmed these patterns in direct comparisons between evolved and ancestral females and found no consequences of polyandry for female fecundity. The absence of differential selection even when initiating populations with major differences in polyandry casts some doubt on the importance of polyandry for female fitness.
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Affiliation(s)
- Andreas Sutter
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn, UK.,School of Biological Sciences, University of East Anglia, Norwich, UK
| | - Laura M Travers
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn, UK.,School of Biological Sciences, University of East Anglia, Norwich, UK
| | - Melanie Weedon
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn, UK
| | - Keiko Oku
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn, UK
| | - Thomas A R Price
- Institute of Integrative Biology, University of Liverpool, Liverpool, UK
| | - Nina Wedell
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn, UK
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28
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Males can evolve lower resistance to sexually transmitted infections to infect their mates and thereby increase their own fitness. Evol Ecol 2019. [DOI: 10.1007/s10682-019-09976-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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29
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García‐Roa R, Chirinos V, Carazo P. The ecology of sexual conflict: Temperature variation in the social environment can drastically modulate male harm to females. Funct Ecol 2019. [DOI: 10.1111/1365-2435.13275] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Roberto García‐Roa
- Behaviour and Evolution Group, Ethology Lab, Cavanilles Institute of Biodiversity and Evolutionary Biology University of Valencia Valencia Spain
| | - Valeria Chirinos
- Behaviour and Evolution Group, Ethology Lab, Cavanilles Institute of Biodiversity and Evolutionary Biology University of Valencia Valencia Spain
| | - Pau Carazo
- Behaviour and Evolution Group, Ethology Lab, Cavanilles Institute of Biodiversity and Evolutionary Biology University of Valencia Valencia Spain
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30
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Nystrand M, Cassidy EJ, Dowling DK. The effects of a bacterial challenge on reproductive success of fruit flies evolved under low or high sexual selection. Ecol Evol 2018; 8:9341-9352. [PMID: 30377505 PMCID: PMC6194216 DOI: 10.1002/ece3.4450] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2018] [Revised: 06/24/2018] [Accepted: 07/09/2018] [Indexed: 01/22/2023] Open
Abstract
The capacity of individuals to cope with stress, for example, from pathogen exposure, might decrease with increasing levels of sexual selection, although it remains unclear which sex should be more sensitive. Here, we measured the ability of each sex to maintain high reproductive success following challenges with either heat-killed bacteria or procedural control, across replicate populations of Drosophila melanogaster evolved under either high or low levels of sexual selection. Our experiment was run across four separate sampling blocks. We found an interaction between bacterial treatment, sexual selection treatment, and sampling block on female reproductive success. Specifically, and only in the fourth block, we observed that bacterial-challenged females that had evolved under high sexual selection, exhibited lower reproductive success than bacterial-challenged females that had evolved under low sexual selection. Furthermore, we could trace this block-specific effect to a reduction in viscosity of the ovipositioning substrate in the fourth block, in which females laid around 50% more eggs than in previous blocks. In contrast, patterns of male reproductive success were consistent across blocks. Males that evolved under high sexual selection exhibited higher reproductive success than their low-selection counterparts, regardless of whether they were subjected to a bacterial challenge or not. Our results are consistent with the prediction that heightened sexual selection will invoke male-specific evolutionary increases in reproductive fitness. Furthermore, our findings suggest that females might pay fitness costs when exposed to high levels of sexual selection, but that these costs may lie cryptic, and only be revealed under certain environmental contexts.
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Affiliation(s)
| | - Elizabeth J. Cassidy
- School of Biological SciencesMonash UniversityClaytonVic.Australia
- Department of Plant and Organismal BiologyUniversity of CopenhagenCopenhagenDenmark
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31
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Stanley CR, Liddiard Williams H, Preziosi RF. Female clustering in cockroach aggregations-A case of social niche construction? Ethology 2018. [DOI: 10.1111/eth.12799] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Christina R. Stanley
- Department of Biological Sciences; University of Chester; Chester UK
- Faculty of Life Sciences; University of Manchester; Manchester UK
| | | | - Richard F. Preziosi
- Faculty of Life Sciences; University of Manchester; Manchester UK
- School of Science and the Environment; Manchester Metropolitan University; Manchester UK
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32
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Abstract
Sexual conflict is acknowledged as pervasive, with the potential to generate and maintain genetic variation. Mechanistic studies of conflict have been important in providing direct evidence for the existence of sexual conflict. They have also led to the growing realization that there is a striking phenotypic diversity of adaptations whose evolution can be shaped by sexually antagonistic selection. The mechanisms involved range from the use of genital spines, claspers, songs, and smells to ejaculate molecules. In one well-studied example, sexual conflict can occur over the sexually antagonistic effects of seminal fluid proteins in Drosophila melanogaster. However, an important puzzle remains, namely, why seminal fluid proteins are so numerous and complex, hence whether all or some are involved in mediating sexual conflict. I hypothesize that this rich diversity and the complexity of traits subject to sexually antagonistic selection in general may arise, at least in part, due to the deployment of sexually antagonistic adaptations in males in a way that lessens the probability of broadscale, strong resistance evolution in females. In elaborating this hypothesis, I explore how research into the evolution of resistance to insecticides, antimicrobials, and vaccines might be used to provide insights into the evolution of female resistance to the effects of sexually antagonistic manipulative traits of males. In this manner, the manipulative traits of males can be resistance-proofed.
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33
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Skwierzyńska AM, Plesnar‐Bielak A. Proximate mechanisms of the differences in reproductive success of males bearing different alleles of Pgdh – a gene involved in a sexual conflict in bulb mite. J Evol Biol 2018; 31:657-664. [DOI: 10.1111/jeb.13250] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 02/09/2018] [Indexed: 11/26/2022]
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34
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Signor SA, Abbasi M, Marjoram P, Nuzhdin SV. Conservation of social effects (Ψ ) between two species of Drosophila despite reversal of sexual dimorphism. Ecol Evol 2017; 7:10031-10041. [PMID: 29238534 PMCID: PMC5723616 DOI: 10.1002/ece3.3523] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 09/19/2017] [Accepted: 09/20/2017] [Indexed: 12/15/2022] Open
Abstract
Indirect genetic effects (IGEs) describe the effect of the genes of social partners on the phenotype of a focal individual. Here, we measure indirect genetic effects using the “coefficient of interaction” (Ψ) to test whether Ψ evolved between Drosophila melanogaster and D. simulans. We compare Ψ for locomotion between ethanol and nonethanol environments in both species, but only D. melanogaster utilizes ethanol ecologically. We find that while sexual dimorphism for locomotion has been reversed in D. simulans, there has been no evolution of social effects between these two species. What did evolve was the interaction between genotype‐specific Ψ and the environment, as D. melanogaster varies unpredictably between environments and D. simulans does not. In this system, this suggests evolutionary lability of sexual dimorphism but a conservation of social effects, which brings forth interesting questions about the role of the social environment in sexual selection.
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Affiliation(s)
- Sarah A Signor
- Program in Molecular and Computational Biology Dornsife College of Letters, Arts and Sciences University of Southern California Los Angeles CA USA
| | - Mohammad Abbasi
- Graduate Program in Computational Biology Dornsife College of Letters, Arts and Sciences University of Southern California Los Angeles CA USA
| | - Paul Marjoram
- Program in Molecular and Computational Biology Dornsife College of Letters, Arts and Sciences University of Southern California Los Angeles CA USA.,Department of Preventive Medicine Keck School of Medicine University of Southern California Los Angeles CA USA
| | - Sergey V Nuzhdin
- Program in Molecular and Computational Biology Dornsife College of Letters, Arts and Sciences University of Southern California Los Angeles CA USA
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35
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Wensing KU, Koppik M, Fricke C. Precopulatory but not postcopulatory male reproductive traits diverge in response to mating system manipulation in Drosophila melanogaster. Ecol Evol 2017; 7:10361-10378. [PMID: 29238561 PMCID: PMC5723610 DOI: 10.1002/ece3.3542] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 09/11/2017] [Accepted: 09/14/2017] [Indexed: 01/01/2023] Open
Abstract
Competition between males creates potential for pre‐ and postcopulatory sexual selection and conflict. Theory predicts that males facing risk of sperm competition should evolve traits to secure their reproductive success. If those traits are costly to females, the evolution of such traits may also increase conflict between the sexes. Conversely, under the absence of sperm competition, one expectation is for selection on male competitive traits to relax thereby also relaxing sexual conflict. Experimental evolution studies are a powerful tool to test this expectation. Studies in multiple insect species have yielded mixed and partially conflicting results. In this study, we evaluated male competitive traits and male effects on female costs of mating in Drosophila melanogaster after replicate lines evolved for more than 50 generations either under enforced monogamy or sustained polygamy, thus manipulating the extent of intrasexual competition between males. We found that in a setting where males competed directly with a rival male for access to a female and fertilization of her ova polygamous males had superior reproductive success compared to monogamous males. When comparing reproductive success solely in double mating standard sperm competition assays, however, we found no difference in male sperm defense competitiveness between the different selection regimes. Instead, we found monogamous males to be inferior in precopulatory competition, which indicates that in our system, enforced monogamy relaxed selection on traits important in precopulatory rather than postcopulatory competition. We discuss our findings in the context of findings from previous experimental evolution studies in Drosophila ssp. and other invertebrate species.
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Affiliation(s)
- Kristina U. Wensing
- Institute for Evolution and BiodiversityUniversity of MuensterMuensterGermany
- Muenster Graduate School of EvolutionUniversity of MuensterMuensterGermany
| | - Mareike Koppik
- Institute for Evolution and BiodiversityUniversity of MuensterMuensterGermany
| | - Claudia Fricke
- Institute for Evolution and BiodiversityUniversity of MuensterMuensterGermany
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36
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Bath E, Bowden S, Peters C, Reddy A, Tobias JA, Easton-Calabria E, Seddon N, Goodwin SF, Wigby S. Sperm and sex peptide stimulate aggression in female Drosophila. Nat Ecol Evol 2017; 1:0154. [PMID: 28580431 PMCID: PMC5447820 DOI: 10.1038/s41559-017-0154] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Female aggression towards other females is associated with reproduction in many taxa, and traditionally thought to be related to the protection or provisioning of offspring, such as through increased resource acquisition. However, the underlying reproductive factors causing aggressive behaviour in females remain unknown. Here we show that female aggression in the fruit fly Drosophila melanogaster is strongly stimulated by the receipt of sperm at mating, and in part by an associated seminal fluid protein, the sex peptide. We further show that the post-mating increase in female aggression is decoupled from the costs of egg production and from post-mating decreases in sexual receptivity. Our results suggest that male ejaculates can have a surprisingly direct influence on aggression in recipient females. Male ejaculate traits thus influence the female social competitive environment with potentially far-reaching ecological and evolutionary consequences.
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Affiliation(s)
- Eleanor Bath
- Edward Grey Institute, Department of Zoology, University of Oxford, Oxford, UK OX1 3PS
| | - Samuel Bowden
- Edward Grey Institute, Department of Zoology, University of Oxford, Oxford, UK OX1 3PS
| | - Carla Peters
- Edward Grey Institute, Department of Zoology, University of Oxford, Oxford, UK OX1 3PS
| | - Anjali Reddy
- Edward Grey Institute, Department of Zoology, University of Oxford, Oxford, UK OX1 3PS
| | - Joseph A Tobias
- Edward Grey Institute, Department of Zoology, University of Oxford, Oxford, UK OX1 3PS.,Faculty of Natural Sciences, Department of Life Sciences, Imperial College, London, UK SW7 2AZ
| | - Evan Easton-Calabria
- Department of International Development, University of Oxford, Oxford, UK OX1 3TB
| | - Nathalie Seddon
- Edward Grey Institute, Department of Zoology, University of Oxford, Oxford, UK OX1 3PS
| | - Stephen F Goodwin
- Centre for Neural Circuits and Behaviour, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK OX1 3SR
| | - Stuart Wigby
- Edward Grey Institute, Department of Zoology, University of Oxford, Oxford, UK OX1 3PS
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37
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Chechi TS, Ali Syed Z, Prasad NG. Virility does not imply immensity: Testis size, accessory gland size and ejaculate depletion pattern do not evolve in response to experimental manipulation of sex ratio in Drosophila melanogaster. JOURNAL OF INSECT PHYSIOLOGY 2017; 98:67-73. [PMID: 27913151 DOI: 10.1016/j.jinsphys.2016.11.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 11/21/2016] [Accepted: 11/22/2016] [Indexed: 06/06/2023]
Abstract
Sperm competition theory predicts that with increase in sperm competition, males either invest more in reproductive organ(s) and/or improve ejaculate investment. We test this idea using experimental evolution in Drosophila melanogaster. We maintained replicate populations of Drosophila melanogaster under male (M) and female (F) biased sex ratio regimes for more than a hundred generations with the result that males from the M regime evolved higher sperm competitive abilities relative to males from the F regime. In the present study, we measured the testes and the accessory gland size of virgin and singly mated males from the M and F regimes. The M and F males do not differ in either testis or accessory gland size. Additionally, ejaculate investment is not different in the M and F males, as measured by reduction in testis and accessory gland sizes. Thus, contrary to theoretical prediction and evidence from other species, we found that evolved differences in sperm competitive ability are not necessarily due to evolution of testis/accessory gland size or strategic ejaculate investment in these populations.
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Affiliation(s)
- Tejinder Singh Chechi
- Indian Institute of Science Education and Research, Mohali, Knowledge City, Sector 81, SAS Nagar, Mohali, Punjab 140306, India
| | - Zeeshan Ali Syed
- Indian Institute of Science Education and Research, Mohali, Knowledge City, Sector 81, SAS Nagar, Mohali, Punjab 140306, India
| | - Nagaraj Guru Prasad
- Indian Institute of Science Education and Research, Mohali, Knowledge City, Sector 81, SAS Nagar, Mohali, Punjab 140306, India.
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38
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Giardina TJ, Clark AG, Fiumera AC. Estimating mating rates in wild Drosophila melanogaster females by decay rates of male reproductive proteins in their reproductive tracts. Mol Ecol Resour 2017; 17:1202-1209. [PMID: 28213940 DOI: 10.1111/1755-0998.12661] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 02/01/2017] [Indexed: 11/29/2022]
Abstract
Female Drosophila melanogaster frequently mate with multiple males in nature as shown through parentage analysis. Although polyandry is well documented, we know little about the timing between mating events in wild Drosophila populations due to the challenge of following behaviours of individual females. In this study, we used the presence of a male reproductive protein that is transferred to the female during mating (Sex Peptide, SP) to determine whether she had recently mated. We sampled females throughout the day, conducted control matings to determine the decay rate of SP within the female reproductive tract and performed computer simulations to fit the observed proportion of mated females to a nonhomogenous Poisson process that defined the expected time between successive matings for a given female. In our control matings, 100% of mated females tested positive for SP 0.5 h after the start of mating (ASM), but only 24% tested positive 24 h ASM. Overall, 35% of wild-caught females tested positive for the presence of SP. Fitting our observed data to our simple nonhomogenous Poisson model provided the inference that females are mating, on average, approximately every 27 h (with 95% credibility interval 23-31 h). Thus, it appears that females are mating a bit less frequently that once per day in this natural population and that mating events tend to occur either early in the morning or late in the afternoon.
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Affiliation(s)
- Thomas J Giardina
- Department of Biological Sciences, Binghamton University, Binghamton, NY, 13902, USA
| | - Andrew G Clark
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, 14853, USA
| | - Anthony C Fiumera
- Department of Biological Sciences, Binghamton University, Binghamton, NY, 13902, USA
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39
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Genevcius BC, Caetano DS, Schwertner CF. Rapid differentiation and asynchronous coevolution of male and female genitalia in stink bugs. J Evol Biol 2017; 30:461-473. [DOI: 10.1111/jeb.13026] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 10/27/2016] [Accepted: 12/07/2016] [Indexed: 02/04/2023]
Affiliation(s)
- B. C. Genevcius
- Department of Ecology and Evolutionary Biology; Graduate Program in Ecology and Evolution; Federal University of São Paulo; Diadema SP Brazil
- Museum of Zoology (MZUSP); University of São Paulo; São Paulo SP Brazil
| | - D. S. Caetano
- Department of Biological Sciences; University of Idaho; Moscow ID USA
| | - C. F. Schwertner
- Department of Ecology and Evolutionary Biology; Graduate Program in Ecology and Evolution; Federal University of São Paulo; Diadema SP Brazil
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40
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Baxter CM, Dukas R. Life history of aggression: effects of age and sexual experience on male aggression towards males and females. Anim Behav 2017. [DOI: 10.1016/j.anbehav.2016.10.022] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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41
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Fritzsche K, Booksmythe I, Arnqvist G. Sex Ratio Bias Leads to the Evolution of Sex Role Reversal in Honey Locust Beetles. Curr Biol 2016; 26:2522-2526. [PMID: 27593373 DOI: 10.1016/j.cub.2016.07.018] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 07/05/2016] [Accepted: 07/08/2016] [Indexed: 11/29/2022]
Abstract
The reversal of conventional sex roles was enigmatic to Darwin, who suggested that it may evolve when sex ratios are female biased [1]. Here we present direct evidence confirming Darwin's hypothesis. We investigated mating system evolution in a sex-role-reversed beetle (Megabruchidius dorsalis) using experimental evolution under manipulated sex ratios and food regimes. In female-biased populations, where reproductive competition among females was intensified, females evolved to be more attractive and the sex roles became more reversed. Interestingly, female-specific mating behavior evolved more rapidly than male-specific mating behavior. We show that sexual selection due to reproductive competition can be strong in females and can target much the same traits as in males of species with conventional mating systems. Our study highlights two central points: the role of ecology in directing sexual selection and the role that females play in mating system evolution.
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Affiliation(s)
- Karoline Fritzsche
- Department of Zoology, University of Graz, Universitätsplatz 2, 8010 Graz, Austria.
| | - Isobel Booksmythe
- Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Göran Arnqvist
- Animal Ecology, Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, 752 36 Uppsala, Sweden
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42
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Evans JP, Garcia-Gonzalez F. The total opportunity for sexual selection and the integration of pre- and post-mating episodes of sexual selection in a complex world. J Evol Biol 2016; 29:2338-2361. [PMID: 27520979 DOI: 10.1111/jeb.12960] [Citation(s) in RCA: 98] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 08/05/2016] [Accepted: 08/05/2016] [Indexed: 12/30/2022]
Abstract
It is well known that sexual selection can target reproductive traits during successive pre- and post-mating episodes of selection. A key focus of recent studies has been to understand and quantify how these episodes of sexual selection interact to determine overall variance in reproductive success. In this article, we review empirical developments in this field but also highlight the considerable variability in patterns of pre- and post-mating sexual selection, attributable to variation in patterns of resource acquisition and allocation, ecological and social factors, genotype-by-environment interaction and possible methodological factors that might obscure such patterns. Our aim is to highlight how (co)variances in pre- and post-mating sexually selected traits can be sensitive to changes in a range of ecological and environmental variables. We argue that failure to capture this variation when quantifying the opportunity for sexual selection may lead to erroneous conclusions about the strength, direction or form of sexual selection operating on pre- and post-mating traits. Overall, we advocate for approaches that combine measures of pre- and post-mating selection across contrasting environmental or ecological gradients to better understand the dynamics of sexual selection in polyandrous species. We also discuss some directions for future research in this area.
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Affiliation(s)
- J P Evans
- Centre for Evolutionary Biology, School of Animal Biology (M092), University of Western Australia, Crawley, WA, Australia
| | - F Garcia-Gonzalez
- Centre for Evolutionary Biology, School of Animal Biology (M092), University of Western Australia, Crawley, WA, Australia.,Doñana Biological Station, Spanish Research Council CSIC, Sevilla, Spain
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43
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McNamara KB, Robinson SP, Rosa ME, Sloan NS, van Lieshout E, Simmons LW. Male-biased sex ratio does not promote increased sperm competitiveness in the seed beetle, Callosobruchus maculatus. Sci Rep 2016; 6:28153. [PMID: 27306351 PMCID: PMC4910101 DOI: 10.1038/srep28153] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 05/27/2016] [Indexed: 11/09/2022] Open
Abstract
Sperm competition risk and intensity can select for adaptations that increase male fertilisation success. Evolutionary responses are examined typically by generating increased strength of sexual selection via direct manipulation of female mating rates (by enforcing monandry or polyandry) or by alteration of adult sex ratios. Despite being a model species for sexual selection research, the effect of sexual selection intensity via adult sex-ratio manipulation on male investment strategies has not been investigated in the seed beetle, Callosobruchus maculatus. We imposed 32 generations of experimental evolution on 10 populations of beetles by manipulating adult sex ratio. Contrary to predictions, males evolving in male-biased populations did not increase their testes and accessory gland size. This absence of divergence in ejaculate investment was also reflected in the fact that males from male-biased populations were not more successful in either preventing females from remating, or in competing directly for fertilisations. These populations already demonstrate divergence in mating behaviour and immunity, suggesting sufficient generations have passed to allow divergence in physiological and behavioural traits. We propose several explanations for the absence of divergence in sperm competitiveness among our populations and the pitfalls of using sex ratio manipulation to assess evolutionary responses to sexual selection intensity.
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Affiliation(s)
- Kathryn B McNamara
- Centre for Evolutionary Biology, School of Animal Biology (M092), the University of Western Australia, Crawley, 6009, Australia
| | - Stephen P Robinson
- Centre for Evolutionary Biology, School of Animal Biology (M092), the University of Western Australia, Crawley, 6009, Australia
| | - Márta E Rosa
- Department of Evolutionary Zoology and Human Biology, University of Debrecen, Debrecen, H-4032, Hungary.,Department of Ecology, Szent István University, Budapest, H-1077, Hungary
| | - Nadia S Sloan
- Centre for Evolutionary Biology, School of Animal Biology (M092), the University of Western Australia, Crawley, 6009, Australia
| | - Emile van Lieshout
- Centre for Evolutionary Biology, School of Animal Biology (M092), the University of Western Australia, Crawley, 6009, Australia
| | - Leigh W Simmons
- Centre for Evolutionary Biology, School of Animal Biology (M092), the University of Western Australia, Crawley, 6009, Australia
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44
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Perry JC, Joag R, Hosken DJ, Wedell N, Radwan J, Wigby S. Experimental evolution under hyper-promiscuity in Drosophila melanogaster. BMC Evol Biol 2016; 16:131. [PMID: 27311887 PMCID: PMC4910217 DOI: 10.1186/s12862-016-0699-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 06/05/2016] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND The number of partners that individuals mate with over their lifetime is a defining feature of mating systems, and variation in mate number is thought to be a major driver of sexual evolution. Although previous research has investigated the evolutionary consequences of reductions in the number of mates, we know little about the costs and benefits of increased numbers of mates. Here, we use a genetic manipulation of mating frequency in Drosophila melanogaster to create a novel, highly promiscuous mating system. We generated D. melanogaster populations in which flies were deficient for the sex peptide receptor (SPR) gene - resulting in SPR- females that mated more frequently - and genetically-matched control populations, and allowed them to evolve for 55 generations. At several time-points during this experimental evolution, we assayed behavioural, morphological and transcriptional reproductive phenotypes expected to evolve in response to increased population mating frequencies. RESULTS We found that males from the high mating frequency SPR- populations evolved decreased ability to inhibit the receptivity of their mates and decreased copulation duration, in line with predictions of decreased per-mating investment with increased sperm competition. Unexpectedly, SPR- population males also evolved weakly increased sex peptide (SP) gene expression. Males from SPR- populations initially (i.e., before experimental evolution) exhibited more frequent courtship and faster time until mating relative to controls, but over evolutionary time these differences diminished or reversed. CONCLUSIONS In response to experimentally increased mating frequency, SPR- males evolved behavioural responses consistent with decreased male post-copulatory investment at each mating and decreased overall pre-copulatory performance. The trend towards increased SP gene expression might plausibly relate to functional differences in the two domains of the SP protein. Our study highlights the utility of genetic manipulations of animal social and sexual environments coupled with experimental evolution.
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Affiliation(s)
- Jennifer C Perry
- Edward Grey Institute, Department of Zoology, University of Oxford, Oxford, UK. .,Jesus College, University of Oxford, Oxford, UK.
| | - Richa Joag
- University of Exeter, Penryn, UK.,Institute of Environmental Sciences, Jagiellonian University, Kraków, Poland
| | | | | | - Jacek Radwan
- Institute of Environmental Sciences, Jagiellonian University, Kraków, Poland
| | - Stuart Wigby
- Edward Grey Institute, Department of Zoology, University of Oxford, Oxford, UK
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45
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Chippindale AK, Berggren M, Alpern JHM, Montgomerie R. Does kin selection moderate sexual conflict in Drosophila? Proc Biol Sci 2016; 282:20151417. [PMID: 26269501 DOI: 10.1098/rspb.2015.1417] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Two recent studies provide provocative experimental findings about the potential influence of kin recognition and cooperation on the level of sexual conflict in Drosophila melanogaster. In both studies, male fruit flies apparently curbed their mate-harming behaviours in the presence of a few familiar or related males, suggesting some form of cooperation mediated by kin selection. In one study, the reduction in agonistic behaviour by brothers apparently rendered them vulnerable to dramatic loss of paternity share when competing with an unrelated male. If these results are robust and generalizable, fruit flies could be a major new focus for the experimental study of kin selection and social evolution. In our opinion, however, the restrictive conditions required for male cooperation to be adaptive in this species make it unlikely to evolve. We investigated these phenomena in two different populations of D. melanogaster using protocols very similar to those in the two previous studies. Our experiments show no evidence for a reduction in mate harm based upon either relatedness or familiarity between males, and no reduction in male reproductive success when two brothers are in the presence of an unfamiliar, unrelated, 'foreign' male. Thus, the reduction of sexual conflict owing to male cooperation does not appear to be a general feature of the species, at least under domestication, and these contrasting results call for further investigation: in new populations, in the field and in the laboratory populations in which these phenomena have been reported.
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Affiliation(s)
- Adam K Chippindale
- Department of Biology, Queen's University, Kingston, Ontario, Canada K7L 3N6
| | - Meredith Berggren
- Department of Biology, Queen's University, Kingston, Ontario, Canada K7L 3N6
| | - Joshua H M Alpern
- Department of Biology, Queen's University, Kingston, Ontario, Canada K7L 3N6
| | - Robert Montgomerie
- Department of Biology, Queen's University, Kingston, Ontario, Canada K7L 3N6
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46
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Debelle A, Ritchie MG, Snook RR. Sexual selection and assortative mating: an experimental test. J Evol Biol 2016; 29:1307-16. [PMID: 26970522 DOI: 10.1111/jeb.12855] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Revised: 02/03/2016] [Accepted: 02/26/2016] [Indexed: 11/29/2022]
Abstract
Mate choice and mate competition can both influence the evolution of sexual isolation between populations. Assortative mating may arise if traits and preferences diverge in step, and, alternatively, mate competition may counteract mating preferences and decrease assortative mating. Here, we examine potential assortative mating between populations of Drosophila pseudoobscura that have experimentally evolved under either increased ('polyandry') or decreased ('monogamy') sexual selection intensity for 100 generations. These populations have evolved differences in numerous traits, including a male signal and female preference traits. We use a two males: one female design, allowing both mate choice and competition to influence mating outcomes, to test for assortative mating between our populations. Mating latency shows subtle effects of male and female interactions, with females from the monogamous populations appearing reluctant to mate with males from the polyandrous populations. However, males from the polyandrous populations have a significantly higher probability of mating regardless of the female's population. Our results suggest that if populations differ in the intensity of sexual selection, effects on mate competition may overcome mate choice.
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Affiliation(s)
- A Debelle
- School of Life Sciences, University of Sussex, Brighton, UK
| | - M G Ritchie
- School of Biology, University of St Andrews, St Andrews, UK
| | - R R Snook
- Animal and Plant Sciences, University of Sheffield, Sheffield, UK
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47
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Schneider J, Atallah J, Levine JD. Social structure and indirect genetic effects: genetics of social behaviour. Biol Rev Camb Philos Soc 2016; 92:1027-1038. [PMID: 26990016 DOI: 10.1111/brv.12267] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 02/23/2016] [Accepted: 02/25/2016] [Indexed: 12/20/2022]
Abstract
The social environment modulates gene expression, physiology, behaviour and patterns of inheritance. For more than 50 years, this concept has been investigated using approaches that include partitioning the social component out of behavioural heritability estimates, studying maternal effects on offspring, and analysing dominance hierarchies. Recent advances have formalized this 'social environment effect' by providing a more nuanced approach to the study of social influences on behaviour while recognizing evolutionary implications. Yet, in most of these formulations, the dynamics of social interactions are not accounted for. Also, the reciprocity between individual behaviour and group-level interactions has been largely ignored. Consistent with evolutionary theory, the principles of social interaction are conserved across a broad range of taxa. While noting parallels in diverse organisms, this review uses Drosophila melanogaster as a case study to revisit what is known about social interaction paradigms. We highlight the benefits of integrating the history and pattern of interactions among individuals for dissecting molecular mechanisms that underlie social modulation of behaviour.
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Affiliation(s)
- Jonathan Schneider
- Department of Biology, University of Toronto at Mississauga, Mississauga, Ontario, L5L 1C6, Canada
| | - Jade Atallah
- Department of Biology, University of Toronto at Mississauga, Mississauga, Ontario, L5L 1C6, Canada
| | - Joel D Levine
- Department of Biology, University of Toronto at Mississauga, Mississauga, Ontario, L5L 1C6, Canada
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48
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Green D, Dalmay T, Chapman T. Microguards and micromessengers of the genome. Heredity (Edinb) 2016; 116:125-34. [PMID: 26419338 PMCID: PMC4806885 DOI: 10.1038/hdy.2015.84] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Revised: 07/23/2015] [Accepted: 08/03/2015] [Indexed: 01/12/2023] Open
Abstract
The regulation of gene expression is of fundamental importance to maintain organismal function and integrity and requires a multifaceted and highly ordered sequence of events. The cyclic nature of gene expression is known as 'transcription dynamics'. Disruption or perturbation of these dynamics can result in significant fitness costs arising from genome instability, accelerated ageing and disease. We review recent research that supports the idea that an important new role for small RNAs, particularly microRNAs (miRNAs), is in protecting the genome against short-term transcriptional fluctuations, in a process we term 'microguarding'. An additional emerging role for miRNAs is as 'micromessengers'-through alteration of gene expression in target cells to which they are trafficked within microvesicles. We describe the scant but emerging evidence that miRNAs can be moved between different cells, individuals and even species, to exert biologically significant responses. With these two new roles, miRNAs have the potential to protect against deleterious gene expression variation from perturbation and to themselves perturb the expression of genes in target cells. These interactions between cells will frequently be subject to conflicts of interest when they occur between unrelated cells that lack a coincidence of fitness interests. Hence, there is the potential for miRNAs to represent both a means to resolve conflicts of interest, as well as instigate them. We conclude by exploring this conflict hypothesis, by describing some of the initial evidence consistent with it and proposing new ideas for future research into this exciting topic.
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Affiliation(s)
- D Green
- Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich, UK
| | - T Dalmay
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, UK
| | - T Chapman
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, UK
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49
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Ramm SA, Edward DA, Claydon AJ, Hammond DE, Brownridge P, Hurst JL, Beynon RJ, Stockley P. Sperm competition risk drives plasticity in seminal fluid composition. BMC Biol 2015; 13:87. [PMID: 26507392 PMCID: PMC4624372 DOI: 10.1186/s12915-015-0197-2] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 10/07/2015] [Indexed: 12/24/2022] Open
Abstract
Background Ejaculates contain a diverse mixture of sperm and seminal fluid proteins, the combination of which is crucial to male reproductive success under competitive conditions. Males should therefore tailor the production of different ejaculate components according to their social environment, with particular sensitivity to cues of sperm competition risk (i.e. how likely it is that females will mate promiscuously). Here we test this hypothesis using an established vertebrate model system, the house mouse (Mus musculus domesticus), combining experimental data with a quantitative proteomics analysis of seminal fluid composition. Our study tests for the first time how both sperm and seminal fluid components of the ejaculate are tailored to the social environment. Results Our quantitative proteomics analysis reveals that the relative production of different proteins found in seminal fluid – i.e. seminal fluid proteome composition – differs significantly according to cues of sperm competition risk. Using a conservative analytical approach to identify differential expression of individual seminal fluid components, at least seven of 31 secreted seminal fluid proteins examined showed consistent differences in relative abundance under high versus low sperm competition conditions. Notably three important proteins with potential roles in sperm competition – SVS 6, SVS 5 and CEACAM 10 – were more abundant in the high competition treatment groups. Total investment in both sperm and seminal fluid production also increased with cues of heightened sperm competition risk in the social environment. By contrast, relative investment in different ejaculate components was unaffected by cues of mating opportunities. Conclusions Our study reveals significant plasticity in different ejaculate components, with the production of both sperm and non-sperm fractions of the ejaculate strongly influenced by the social environment. Sperm competition risk is thus shown to be a key factor in male ejaculate production decisions, including driving plasticity in seminal fluid composition. Electronic supplementary material The online version of this article (doi:10.1186/s12915-015-0197-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Steven A Ramm
- Mammalian Behaviour and Evolution Group, Institute of Integrative Biology, University of Liverpool, Leahurst Campus, Chester High Road, Neston, CH64 7TE, UK. .,Evolutionary Biology, Bielefeld University, Morgenbreede 45, 33615, Bielefeld, Germany.
| | - Dominic A Edward
- Mammalian Behaviour and Evolution Group, Institute of Integrative Biology, University of Liverpool, Leahurst Campus, Chester High Road, Neston, CH64 7TE, UK.
| | - Amy J Claydon
- Mammalian Behaviour and Evolution Group, Institute of Integrative Biology, University of Liverpool, Leahurst Campus, Chester High Road, Neston, CH64 7TE, UK. .,Centre for Proteome Research, Institute of Integrative Biology, University of Liverpool, Biosciences Building, Crown Street, Liverpool, L69 7ZB, UK.
| | - Dean E Hammond
- Centre for Proteome Research, Institute of Integrative Biology, University of Liverpool, Biosciences Building, Crown Street, Liverpool, L69 7ZB, UK.
| | - Philip Brownridge
- Centre for Proteome Research, Institute of Integrative Biology, University of Liverpool, Biosciences Building, Crown Street, Liverpool, L69 7ZB, UK.
| | - Jane L Hurst
- Mammalian Behaviour and Evolution Group, Institute of Integrative Biology, University of Liverpool, Leahurst Campus, Chester High Road, Neston, CH64 7TE, UK.
| | - Robert J Beynon
- Centre for Proteome Research, Institute of Integrative Biology, University of Liverpool, Biosciences Building, Crown Street, Liverpool, L69 7ZB, UK.
| | - Paula Stockley
- Mammalian Behaviour and Evolution Group, Institute of Integrative Biology, University of Liverpool, Leahurst Campus, Chester High Road, Neston, CH64 7TE, UK.
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50
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Evans GMV, Nowlan T, Shuker DM. Patterns of reproductive isolation within and between twoLygaeusspecies characterized by sexual conflicts over mating. Biol J Linn Soc Lond 2015. [DOI: 10.1111/bij.12639] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Gethin M. V. Evans
- Institute of Evolutionary Biology; University of Edinburgh; West Mains Road Edinburgh EH9 3JT UK
| | - Toby Nowlan
- Institute of Evolutionary Biology; University of Edinburgh; West Mains Road Edinburgh EH9 3JT UK
| | - David M. Shuker
- School of Biology; University of St Andrews; Harold Mitchell Building St Andrews KY16 9TH UK
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