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Macedo-Rego RC, Jennions MD, Santos ESA. Does the potential strength of sexual selection differ between mating systems with and without defensive behaviours? A meta-analysis. Biol Rev Camb Philos Soc 2024. [PMID: 38597347 DOI: 10.1111/brv.13078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 03/18/2024] [Accepted: 03/21/2024] [Indexed: 04/11/2024]
Abstract
The Darwin-Bateman paradigm predicts that females enhance their fitness by being choosy and mating with high-quality males, while males should compete to mate with as many females as possible. In many species, males enhance their fitness by defending females and/or resources used by females. That is, males directly defend access to mating opportunities. However, paternity analyses have repeatedly shown that females in most species mate polyandrously, which contradicts traditional expectations that male defensive behaviours lead to monandry. Here, in an extensive meta-analysis, encompassing 109 species and 1026 effect sizes from across the animal kingdom, we tested if the occurrence of defensive behaviours modulates sexual selection on females and males. If so, we can illuminate the extent to which males really succeed in defending access to mating and fertilisation opportunities. We used four different indices of the opportunity for sexual selection that comprise pre-mating and/or post-mating episodes of selection. We found, for both sexes, that the occurrence of defensive behaviours does not modulate the potential strength of sexual selection. This implies that male defensive behaviours do not predict the true intensity of sexual selection. While the most extreme levels of sexual selection on males are in species with male defensive behaviours, which indicates that males do sometimes succeed in restricting females' re-mating ability (e.g. elephant seals, Mirounga leonina), estimates of the opportunity for sexual selection vary greatly across species, regardless of whether or not defensive behaviours occur. Indeed, widespread polyandry shows that females are usually not restricted by male defensive behaviours. In addition, our results indicate that post-mating episodes of selection, such as cryptic female choice and sperm competition, might be important factors modulating the opportunity for sexual selection. We discuss: (i) why male defensive behaviours fail to lower the opportunity for sexual selection among females or fail to elevate it for males; (ii) how post-mating events might influence sexual selection; and (iii) the role of females as active participants in sexual selection. We also highlight that inadequate data reporting in the literature prevented us from extracting effect sizes from many studies that had presumably collected the relevant data.
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Affiliation(s)
- Renato C Macedo-Rego
- Programa de Pós-graduação em Ecologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, trav. 14, no. 321, São Paulo, SP 05508-090, Brazil
- Division of Ecology & Evolution, Research School of Biology, Australian National University, Canberra, ACT, Australia
| | - Michael D Jennions
- Division of Ecology & Evolution, Research School of Biology, Australian National University, Canberra, ACT, Australia
- Stellenbosch Institute for Advanced Study (STIAS), Wallenberg Centre, 10 Marais Street, Stellenbosch, 7600, South Africa
| | - Eduardo S A Santos
- Programa de Pós-graduação em Ecologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, trav. 14, no. 321, São Paulo, SP 05508-090, Brazil
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2
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Pärssinen V, Simmons LW, Kvarnemo C. Mating competition among females: testing the distinction between natural and sexual selection in an insect. ROYAL SOCIETY OPEN SCIENCE 2024; 11:240191. [PMID: 38586425 PMCID: PMC10999239 DOI: 10.1098/rsos.240191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Accepted: 02/10/2024] [Indexed: 04/09/2024]
Abstract
In species where females compete for mates, the male often provides the female with resources in addition to gametes. A recently suggested definition of sexual selection proposed that if females only benefit from additional resources that come with each mating and not additional gametes, female intrasexual competition for mating opportunities would result in natural selection rather than sexual selection. The nuptial gift-giving bushcricket Kawanaphila nartee has dynamic sex roles and has been a textbook example of sexual selection acting on females via mating competition. We investigated whether females of this species gain fitness benefits from nuptial gifts, additional ejaculates or both by controlling the number of matings and whether the female was allowed to consume the nutritious gift (spermatophylax) at mating. We found that egg production per day of life increased with the number of additional matings, both with and without spermatophylax consumption, but consuming the spermatophylax had an additional positive effect on the number of eggs. These effects were particularly strong in females with shorter lifespans. We discuss how the recently suggested definition of sexual selection applies to nuptial-feeding insects and conclude that both natural and sexual selections influence mating competition in K. nartee females.
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Affiliation(s)
- Varpu Pärssinen
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg40530, Sweden
| | - Leigh W. Simmons
- Centre for Evolutionary Biology, School of Biological Sciences (M092), The University of Western Australia, Crawley6009, Australia
| | - Charlotta Kvarnemo
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg40530, Sweden
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3
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Fissette SD, Buchinger TJ, Tamrakar S, Scott AM, Li W. Sensory trap leads to reliable communication without a shift in nonsexual responses to the model cue. Behav Ecol 2024; 35:arae006. [PMID: 38379814 PMCID: PMC10878365 DOI: 10.1093/beheco/arae006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 12/08/2023] [Accepted: 01/31/2024] [Indexed: 02/22/2024] Open
Abstract
The sensory trap model of signal evolution suggests that males manipulate females into mating using traits that mimic cues used in a nonsexual context. Despite much empirical support for sensory traps, little is known about how females evolve in response to these deceptive signals. Female sea lamprey (Petromyzon marinus) evolved to discriminate a male sex pheromone from the larval odor it mimics and orient only toward males during mate search. Larvae and males release the attractant 3-keto petromyzonol sulfate (3kPZS), but spawning females avoid larval odor using the pheromone antagonist, petromyzonol sulfate (PZS), which larvae but not males, release at higher rates than 3kPZS. We tested the hypothesis that migratory females also discriminate between larval odor and the male pheromone and orient only to larval odor during anadromous migration, when they navigate within spawning streams using larval odor before they begin mate search. In-stream behavioral assays revealed that, unlike spawning females, migratory females do not discriminate between mixtures of 3kPZS and PZS applied at ratios typical of larval versus male odorants. Our results indicate females discriminate between the sexual and nonsexual sources of 3kPZS during but not outside of mating and show sensory traps can lead to reliable sexual communication without females shifting their responses in the original context.
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Affiliation(s)
- Skye D Fissette
- Department of Fisheries and Wildlife, Michigan State University, 13 Natural Resources Building, 480 Wilson Rd., East Lansing MI 48824, USA
| | - Tyler J Buchinger
- Department of Fisheries and Wildlife, Michigan State University, 13 Natural Resources Building, 480 Wilson Rd., East Lansing MI 48824, USA
| | - Sonam Tamrakar
- Department of Fisheries and Wildlife, Michigan State University, 13 Natural Resources Building, 480 Wilson Rd., East Lansing MI 48824, USA
| | - Anne M Scott
- Department of Fisheries and Wildlife, Michigan State University, 13 Natural Resources Building, 480 Wilson Rd., East Lansing MI 48824, USA
| | - Weiming Li
- Department of Fisheries and Wildlife, Michigan State University, 13 Natural Resources Building, 480 Wilson Rd., East Lansing MI 48824, USA
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Ježová Z, Prokop P, Zvaríková M, Zvarík M. Unraveling the Significance of Draglines: Female Sexual Signalization in the Nursery-Web Spider, Pisaura mirabilis. INSECTS 2023; 14:765. [PMID: 37754733 PMCID: PMC10532251 DOI: 10.3390/insects14090765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 09/06/2023] [Accepted: 09/11/2023] [Indexed: 09/28/2023]
Abstract
Chemical signals used by animals to attract the opposite sex are well known in insects, but heavily understudied in spiders. We investigated the role of chemical signals in female draglines in a gift-giving spider, Pisaura mirabilis, using combined data from behavioral tests and high-performance liquid chromatography (HPLC). We also investigated whether the quality of sexual signalization is influenced by crucial factors, such as female spider ontogeny, nutritional status, and mating status. We found that draglines of adult (versus subadult) and hungry (versus fed) females stimulated male motivation to produce nuptial gift, and highly sexually excited males invested more silk in gift production than less sexually excited males. Unexpectedly, chemical signals of eggsac-carrying females were similarly sexually attractive to draglines of adult females not carrying eggsac. HPLC identified significant chemical differences in female draglines, but these differences did not always correspond to male behavior. The integration of behavioral and chemical approaches is required to better understand animal behavior in future research.
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Affiliation(s)
- Zuzana Ježová
- Department of Environmental Ecology and Landscape Management, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, 842 15 Bratislava, Slovakia; (Z.J.)
| | - Pavol Prokop
- Department of Environmental Ecology and Landscape Management, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, 842 15 Bratislava, Slovakia; (Z.J.)
- Institute of Zoology, Slovak Academy of Sciences, Dúbravská Cesta 9, 845 06 Bratislava, Slovakia
| | - Martina Zvaríková
- Department of Environmental Ecology and Landscape Management, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, 842 15 Bratislava, Slovakia; (Z.J.)
| | - Milan Zvarík
- Department of Nuclear Physics and Biophysics, Faculty of Mathematics, Physics and Informatics, Comenius University, Mlynská Dolina F1, 842 48 Bratislava, Slovakia;
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5
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Burke NW, Holwell G. Costs and benefits of polyandry in a sexually cannibalistic mantis. J Evol Biol 2023; 36:412-423. [PMID: 36537353 DOI: 10.1111/jeb.14135] [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: 07/06/2022] [Revised: 10/31/2022] [Accepted: 11/16/2022] [Indexed: 12/24/2022]
Abstract
Mating with more than one male often provides direct or indirect benefits to female fitness but can also increase the chance of injury and death. Costs of mating are expected to increase linearly with increasing mating number. But how such costs interact with benefits to determine the net payoff of mating multiply is not well understood. Using the highly cannibalistic Springbok mantis, Miomantis caffra, a species where females are stabbed in the abdomen by males during violent premating struggles that males initiate to avoid being cannibalized, we took an experimental approach to assess the economics of polyandry under the risk of external, male-inflicted injury. We predicted that females that mate multiply would be more likely to show abdominal injuries, have higher prereproductive mortality, produce fewer offspring and be more likely to engage in pre-mating cannibalism to avoid unwanted matings. In line with our predictions, we found that the likelihood of abdominal injury was highest among females that mated at least once, and prereproductive death was highest among females that mated twice or three times. Virgin females completely avoided these costs and produced some offspring parthenogenetically but not enough to provide a net benefit. Although mating was better than not mating, there was no singularly optimal mating number: females that mated once and three times produced similarly high numbers of offspring from the first ootheca, which resulted in an intermediate trough in offspring production at two matings. We also found little evidence that cannibalism was deployed as a mate-avoidance strategy: females consistently attacked and consumed males regardless of how many times they mated or how long they were housed with males. Our results suggest the possibility of two distinct mating strategies in M. caffra, where females either mate at a lower frequency to minimize costs or at a higher frequency to maximize benefits. We discuss possible explanations for this bimodal pattern in offspring production.
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Affiliation(s)
- Nathan W Burke
- School of Biological Sciences, University of Auckland, Auckland, New Zealand.,Institute of Cell and Systems Biology of Animals, University of Hamburg, Hamburg, Germany
| | - Gregory Holwell
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
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6
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Angelakakis A, Turetzek N, Tuni C. Female mating rates and their fitness consequences in the common house spider Parasteatoda tepidariorum. Ecol Evol 2022; 12:e9678. [PMID: 36590337 PMCID: PMC9797470 DOI: 10.1002/ece3.9678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 11/29/2022] [Accepted: 12/06/2022] [Indexed: 12/31/2022] Open
Abstract
Mating systems, with varying female mating rates occurring with the same partner (monandry) or with multiple mates (polyandry), can have far reaching consequences for population viability and the rate of gene flow. Here, we investigate the mating rates of the common house spider Parasteatoda tepidariorum (Theridiidae), an emerging model for genetic studies, with yet undescribed reproductive behavior. It is hypothesized that spiders belonging to this family have low re-mating rates. We paired females twice with the same male (monandry) or with different males (polyandry), and recorded behaviors, mating success and fitness resulting from single- and double-matings, either monandrous or polyandrous. Despite the study being explorative in nature, we predict successful matings to be more frequent during first encounters, to reduce female risk of remaining unmated. For re-mating to be adaptive, we expect higher fitness of double-mated females, and polyandrous females to experience highest mating success and fitness if reproductive gains are achieved by mating with multiple partners. We show that the majority of the females did not mate, and those that did mated only once, not necessarily on their first encounter. The likelihood of re-mating did not differ between monandrous and polyandrous encounters and female mating experience (mated once, twice monandrous, twice polyandrous) did not affect fitness, indicated by similar offspring production. Female twanging of the web leads to successful matings suggesting female behavioral receptivity. Cannibalism rates were low and mostly occurred pre-copulatory. We discuss how the species ecology, with potentially high mating costs for males and limited female receptivity, may shape a mating system with low mating rates.
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Affiliation(s)
- Apostolos Angelakakis
- Behavioral Ecology, Faculty of BiologyLudwig‐Maximilians‐University MunichPlanegg‐MartinsriedGermany,Evolutionary Ecology, Faculty of BiologyLudwig‐Maximilians‐University MunichPlanegg‐MartinsriedGermany
| | - Natascha Turetzek
- Evolutionary Ecology, Faculty of BiologyLudwig‐Maximilians‐University MunichPlanegg‐MartinsriedGermany
| | - Cristina Tuni
- Behavioral Ecology, Faculty of BiologyLudwig‐Maximilians‐University MunichPlanegg‐MartinsriedGermany
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7
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Matzke M, Toft S, Bechsgaard J, Pold Vilstrup A, Uhl G, Künzel S, Tuni C, Bilde T. Sperm competition intensity affects sperm precedence patterns in a polyandrous gift-giving spider. Mol Ecol 2022; 31:2435-2452. [PMID: 35178803 DOI: 10.1111/mec.16405] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 01/26/2022] [Accepted: 02/08/2022] [Indexed: 11/28/2022]
Abstract
Sperm competition drives traits that enhance fertilization success. The amount of sperm transferred relative to competitors is key for attaining paternity. Female reproductive morphology and male mating order may also influence fertilization, however the outcome for sperm precedence under intense sperm competition remains poorly understood. In the polyandrous spider Pisaura mirabilis, males offer nuptial gifts which prolong copulation and increase sperm transfer, factors proposed to alter sperm precedence patterns under strong sperm competition. First, we assessed the degree of female polyandry by genotyping wild broods. A conservative analysis identified up to 4 sires, with a mean of 2 sires per brood, consistent with an optimal mating female rate. Then we asked whether intense sperm competition shifts sperm precedence patterns from first male priority, as expected from female morphology, to last male advantage. We varied sexual selection intensity experimentally and determined competitive fertilization outcome by genotyping broods. In double matings, one male monopolised paternity regardless of mating order. A mating order effect with first male priority was revealed when females were mated to 4 males, however this effect disappeared when females were mated to 6 males, likely due to increased sperm mixing. The proportion of males that successfully sired offspring drastically decreased with the number of competitors. Longer copulations translated into higher paternity shares independently of mating order, reinforcing the advantage of traits that prolong copulation duration under intense competition, such as the nuptial gift. Sperm competition intensity enhances the impact of competitive sexual traits and imposes multiple effects on paternity.
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Affiliation(s)
- Magdalena Matzke
- Department of Biology, Ludwig Maximilian University of Munich, Großhaderner Str. 2, 82152, Planegg-Martinsried, Germany
| | - Søren Toft
- Department of Biology, Aarhus University, Ny Munkegade 116, DK-8000, Aarhus C, Denmark
| | - Jesper Bechsgaard
- Department of Biology, Aarhus University, Ny Munkegade 116, DK-8000, Aarhus C, Denmark
| | - Astrid Pold Vilstrup
- Department of Biology, Aarhus University, Ny Munkegade 116, DK-8000, Aarhus C, Denmark.,Department of Molecular Biology and Genetics, Aarhus University, DK-8000, Aarhus C, Denmark
| | - Gabriele Uhl
- General and Systematic Zoology, University of Greifswald, Zoological Institute and Museum, Loitzer Straße 26, D-17489, Greifswald, Germany
| | - Sven Künzel
- Department for Evolutionary Genetics, Max Planck Institute for Evolutionary Biology, August-Thienemann Straße 2, D-24306, Plön, Germany
| | - Cristina Tuni
- Department of Biology, Ludwig Maximilian University of Munich, Großhaderner Str. 2, 82152, Planegg-Martinsried, Germany
| | - Trine Bilde
- Department of Biology, Aarhus University, Ny Munkegade 116, DK-8000, Aarhus C, Denmark
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8
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Heimerl D, Dudová P, Wacker K, Schenkel E, Despréaux G, Tuni C. Adult sex ratio and male body condition affect alternative reproductive tactics in a spider. Behav Ecol 2021. [DOI: 10.1093/beheco/arab138] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Biases in adult sex ratios can alter the intensity of sexual selection by enhancing competition for mates. Under intense competition males increase their investment in behaviors to outcompete rivals (e.g., fighting). Yet, given that in male-biased environments mating opportunities are rare males may alternatively reduce costly courtship and/or adopt alternative reproductive tactics (ARTs). Males of the spider Pisaura mirabilis adopt different mating tactics, offering females genuine nuptial gifts (prey), nutritionally worthless gifts (prey leftovers), or no gifts. To test whether behavioral shifts between gift tactics are triggered by changes in the competitive environment, we established replicate spider populations under natural conditions at varying adult sex ratios (male-biased, female-biased and equal) and sampled gift tactics repeatedly over time. We additionally explored how male individual traits, such as body size and condition, affect the expression of ARTs. In male-biased populations males produced more gifts but of low quality, suggesting competition to trigger increased mating effort to ensure mate acquisition and fertilizations, but through a worthless gift tactic. Production of gifts and of genuine gifts was favored by high body condition, pointing to energetic limitations as being central for male reproductive capacity. We hence highlight two co-existing mechanisms at play to explain ARTs in this system, the competitive social environment where expression of gift tactics is based on optimal-decision making to overcome competition, and a conditional strategy linked to the individual’s energetic state.
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Affiliation(s)
- Daniel Heimerl
- Department of Biology, Ludwig Maximilian University of Munich, Großhaderner Str. 2 82152 Planegg-Martinsried, Germany
| | - Pavla Dudová
- Czech Academy of Sciences, Biology Centre, Institute of Entomology, Branišovská 1160/31, České Budějovice, Czech Republic
- Department of Zoology, Faculty of Science, University of South Bohemia, Branišovská 1645/31A, České Budějovice, Czech Republic
| | - Karoline Wacker
- Department of Biology, Ludwig Maximilian University of Munich, Großhaderner Str. 2 82152 Planegg-Martinsried, Germany
| | - Elisa Schenkel
- Department of Biology, Ludwig Maximilian University of Munich, Großhaderner Str. 2 82152 Planegg-Martinsried, Germany
| | - Garance Despréaux
- Department of Biology, Ludwig Maximilian University of Munich, Großhaderner Str. 2 82152 Planegg-Martinsried, Germany
| | - Cristina Tuni
- Department of Biology, Ludwig Maximilian University of Munich, Großhaderner Str. 2 82152 Planegg-Martinsried, Germany
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9
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Beyer M, Mangliers J, Tuni C. Silk-borne chemicals of spider nuptial gifts elicit female gift acceptance. Biol Lett 2021; 17:20210386. [PMID: 34727704 PMCID: PMC8563295 DOI: 10.1098/rsbl.2021.0386] [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: 07/19/2021] [Accepted: 10/11/2021] [Indexed: 11/12/2022] Open
Abstract
Chemical communication is important in a reproductive context for conveying information used for mate recognition and/or assessment during courtship and mating. Spider silk is a common vehicle for chemical communication between the sexes. However, despite being well described in females, male silk-borne chemicals remain largely unexplored. Males of the spider Pisaura mirabilis silk-wrap prey (i.e. nuptial gifts) that is offered to females during courtship and eaten by the female during mating. Interestingly, rejected males often add more silk to their gift which leads to successful mating, suggesting the presence of silk-borne chemicals that facilitate female gift acceptance. To test this hypothesis, we offered females standardized gifts covered with male silk that was either washed in solvents or unwashed, respectively, to remove or not any chemically active components. We scored female gift acceptance, and as expected in the case chemicals that mediate female mating behaviour are present in male silk, females were more likely to accept gifts covered with unwashed silk. Our findings suggest that silk-borne chemicals of nuptial gifts prime female responses, potentially signalling male quality or manipulating females into mating beyond their interests given the occurrence of male cheating behaviour via nutritionally worthless gifts in this system.
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Affiliation(s)
- Michelle Beyer
- Department of Biology, Ludwig-Maximilians-University of Munich, Großhaderner Str. 2, Planegg-Martinsried 82152, Germany
| | - Julia Mangliers
- Department of Biology, Ludwig-Maximilians-University of Munich, Großhaderner Str. 2, Planegg-Martinsried 82152, Germany
| | - Cristina Tuni
- Department of Biology, Ludwig-Maximilians-University of Munich, Großhaderner Str. 2, Planegg-Martinsried 82152, Germany
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10
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Differential allocation in a gift-giving spider: males adjust their reproductive investment in response to female condition. BMC Ecol Evol 2021; 21:140. [PMID: 34238218 PMCID: PMC8268551 DOI: 10.1186/s12862-021-01870-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 06/25/2021] [Indexed: 11/24/2022] Open
Abstract
Background When males are selective, they can either reject low-quality females or adjust their reproductive investment in response to traits that indicate female quality (e.g., body size or condition). According to the differential allocation hypothesis, males increase their reproductive investment when paired with high-quality females (positive differential allocation) or increase their reproductive investment when paired with low-quality females (negative differential allocation). This hypothesis has been proposed for monogamous species with biparental care, and most empirical studies focus on birds. Here we used the polygamous spider Paratrechalea ornata, in which males offer prey wrapped in silk as nuptial gifts, to test whether males adjust their reproductive investment in gift size, pre-copulatory and copulatory courtship, and sperm transfer in response to female body condition. Results Males exposed to females in good body condition added more flies to the gift, stimulated these females longer with abdominal touches during pre-copulatory courtship, and had longer pedipalp insertions than males exposed to females in poor body condition. Female condition affected neither silk investment in nuptial gift wrapping nor the quantity of sperm transferred by males. Finally, females in good body condition oviposited faster after copulation and laid more eggs than females in poor body condition. Conclusions We provide experimental evidence that males of a gift-giving spider exhibit positive differential allocation in three key aspects of their reproductive investment: the size of the nutritious gift, duration of pre-copulatory courtship, and duration of pedipalp insertions, which is regarded as a form of copulatory courtship in spiders. This positive differential allocation is likely associated with the benefits of copulating with females in good body condition. These females are more fecund and oviposit faster after copulation than females in poor body condition, which under natural field conditions probably reduces the risk of multiple matings and thus the level of sperm competition faced by the males. As a final remark, our findings indicate that the hypothesis of differential allocation also applies to species with a scramble competition mating system, in which males heavily invest in nuptial gift construction, but not in parental care. Supplementary Information The online version contains supplementary material available at 10.1186/s12862-021-01870-1.
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11
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Martínez Villar M, Trillo MC, Albo MJ. Ineffective nuptial gifts suggest female emancipation from sensory exploitation. Behav Ecol Sociobiol 2021. [DOI: 10.1007/s00265-021-02994-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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12
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Eberhard MJB, Möller TA, Uhl G. Dragline silk reveals female developmental stage and mediates male vibratory courtship in the nuptial gift‐giving spider
Pisaura mirabilis. Ethology 2020. [DOI: 10.1111/eth.13124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Monika J. B. Eberhard
- General Zoology and Zoological Systematics Zoological Institute and Museum University of Greifswald Greifswald Germany
| | - Timon A. Möller
- General Zoology and Zoological Systematics Zoological Institute and Museum University of Greifswald Greifswald Germany
| | - Gabriele Uhl
- General Zoology and Zoological Systematics Zoological Institute and Museum University of Greifswald Greifswald Germany
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13
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Abstract
Abstract
Females mate multiply despite numerous costs. It is well established that polyandry can result in sexual conflict, favoring male adaptations that prevent sperm competition often to the disadvantage of the female. Such adaptations are extreme in spiders with one-shot genitalia of which parts break off and act as mating plugs, rendering them dysfunctional. In the spider Argiope bruennichi, mating plugs effectively prevent further males from inseminating and males that inseminate and plug both genital openings of a female secure exclusive paternity. However, females frequently prevent monopolization by attacking and cannibalizing males during their first copulation, leaving their second spermatheca free for another male. Here, we test whether the high frequency of sexual cannibalism evolved as a female adaptation to resist monopolization and secure indirect benefits of polyandry. To standardize conditions, we double-mated females either with the same or two different males and prevented male consumption. Using a split-brood design, we raised offspring to maturity under poor and rich food conditions and measured their survival, duration of juvenile phase, and adult body mass. Under low food, daughters of polyandrous mothers matured later but slightly heavier than daughters of monandrous females. Since the adaptive value of this combination is unclear, these findings lend no conclusive support to our hypothesis. We discuss the stereotypic nature of the female attack in the context of antagonistic co-evolution considering previous studies that found modest direct benefits of cannibalism as well as a potential for non-additive benefits.
Significance statement
Sexual conflict is extreme in spiders where sexual cannibalism impairs male mating rates. Males of the spider Argiope bruennichi possess one-shot genitalia which they break off to plug female genital openings. They gain exclusive paternity with a female if two copulations are achieved and both genital openings plugged. Females, however, stereotypically attack every male at the onset of copulation, limiting most males to single copulation but retaining the option to secure potential benefits of polyandry. Previous studies revealed weak direct and non-additive indirect benefits of multiple mating. In this study, we tested for the presence of additive genetic benefits but again found only inconclusive evidence for adaptive differences in offspring quality between monandrous and polyandrous females. All results combined, we here speculate that the stereotypic female attack might be a ghost of a past antagonistic co-evolution.
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14
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Jigisha, Iglesias-Carrasco M, Vincent A, Head ML. Disentangling the costs of mating and harassment across different environments. Anim Behav 2020. [DOI: 10.1016/j.anbehav.2020.05.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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15
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Dutra AL, Schlindwein C, Oliveira R. Females of a solitary bee reject males to collect food for offspring. Behav Ecol 2020. [DOI: 10.1093/beheco/araa026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
The time dedicated to courtship and copulation is the most general cost of mating for females. However, quantitative estimates of this cost and the consequences for female mating behavior have been investigated for only a few model organisms and mostly under laboratory conditions. We determined the costs of copulations and persistent courtship by males in terms of time for females of the solitary bee Anthrenoides micans. We estimated the rate and duration of male mating behaviors and the consequences for sexual interactions for females with respect to the loss of foraging opportunity in the wild. Males invested most of their time searching for mates and intercepted foraging females every 3 min. Copulas lasted, on average, 10 times longer than the time females took to resist male mating attempts. Despite the high frequency of these rejections (82%), females spent 3-fold more time copulating than rejecting males. Considering the rate of encounters with males and the mean duration of flower visits by females, we estimated that females would perform 64% fewer flower visits per hour if they accepted all copulation attempts. The loss of time is especially significant in the natural habitat of the species, where host cacti blossom for extraordinary short periods of time and females compete with other cacti-specialized bees and conspecifics. Because the offspring production of a female solitary bee depends on its pollen collection capacity, reduced foraging performance directly influences female reproductive success.
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Affiliation(s)
- Ana Laura Dutra
- Programa de Pós-Graduação em Ecologia, Conservação e Manejo da Vida Silvestre, Universidade Federal de Minas Gerais, Pampulha, Belo Horizonte, Minas Gerais, Brazil
| | - Clemens Schlindwein
- Departamento de Botânica, Universidade Federal de Minas Gerais, Pampulha, Belo Horizonte, Minas Gerais, Brazil
| | - Reisla Oliveira
- Programa de Pós-Graduação em Ecologia, Conservação e Manejo da Vida Silvestre, Universidade Federal de Minas Gerais, Pampulha, Belo Horizonte, Minas Gerais, Brazil
- Departamento de Genética, Ecologia e Evolução, Universidade Federal de Minas Gerais, Pampulha, Belo Horizonte, Minas Gerais, Brazil
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16
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Vincent A, Head ML, Iglesias-Carrasco M. Sexual conflict and the environment: teasing apart effects arising via males and females. Anim Behav 2020. [DOI: 10.1016/j.anbehav.2020.01.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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17
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Albo MJ, Franco-Trecu V, Wojciechowski FJ, Toft S, Bilde T. Maintenance of deceptive gifts in a natural spider population: ecological and demographic factors. Behav Ecol 2019. [DOI: 10.1093/beheco/arz040] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
AbstractAlternative mating tactics are expected to occur predominantly when mate competition is intense, resources are in short supply, or as a result of asymmetric power relationships between individuals. Males of the nuptial gift-giving spider Pisaura mirabilis use a prevailing tactic of offering a nutritive gift (insect prey) and a deceptive tactic of offering a worthless gift (consumed prey) to prospective mates. If the male’s tactic depends on precopulatory male–male competition, worthless gifts should occur primarily late in the season, when the operational sex ratio (OSR) becomes male-biased. If it depends on resource availability and/or postcopulatory sexual selection (sperm competition), worthless gifts should occur mostly early in the mating season, when prey availability is low and most females are unmated (i.e., postcopulatory sexual selection is weak). Nuptial gift construction correlated positively with prey availability and negatively with OSR, suggesting that males increase reproductive effort when resource and mate availability increase. We did not find evidence for body condition affecting male tactic use. Male size had a marked effect on the reproductive tactic employed. Males that matured early in the season were very small and employed mostly the nutritive gift tactic during their short life. Among the males that matured later and persisted through the season, relatively small males employed the worthless gift tactic whereas large males employed the nutritive gift tactic. We suggest that the existence of 2 distinct life-history strategies among males (early small and late large size) interacts with environmental and demographic conditions to maintain the deceptive tactic.
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Affiliation(s)
- Maria J Albo
- Departamento de Ecología y Biología Evolutiva, Instituto de Investigaciones Biológicas Clemente Estable, Avenida Italia, Montevideo, Uruguay
- Department of Bioscience, Aarhus University, Ny Munkegade, Aarhus C, Denmark
| | - Valentina Franco-Trecu
- Departamento de Ecología y Evolución, Facultad de Ciencias, Universidad de la República, Iguá, Montevideo, Uruguay
| | - Filip J Wojciechowski
- Department of Bioscience, Aarhus University, Ny Munkegade, Aarhus C, Denmark
- Department of Human Evolutionary Ecology, Adam Mickiewicz University, ul. Umultowska Poznań, Poland
| | - Søren Toft
- Department of Bioscience, Aarhus University, Ny Munkegade, Aarhus C, Denmark
| | - Trine Bilde
- Department of Bioscience, Aarhus University, Ny Munkegade, Aarhus C, Denmark
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18
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Boulton RA, Cook N, Greenway EV(G, Glaser GL, Green J, Shuker DM. Local mate competition modifies the costs of mating in a mostly monandrous parasitoid wasp. Behav Ecol 2019. [DOI: 10.1093/beheco/ary181] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Affiliation(s)
- Rebecca A Boulton
- School of Biology, University of St Andrews, St Andrews, UK
- College of Life and Environmental Sciences, University of Exeter, Penryn, Cornwall, UK
| | - Nicola Cook
- School of Biology, University of St Andrews, St Andrews, UK
| | | | | | - Jade Green
- School of Biology, University of St Andrews, St Andrews, UK
| | - David M Shuker
- School of Biology, University of St Andrews, St Andrews, UK
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19
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The fitness cost to females of exposure to males does not depend on water availability in seed beetles. Anim Behav 2018. [DOI: 10.1016/j.anbehav.2018.06.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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20
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Ghislandi PG, Pekár S, Matzke M, Schulte-Döinghaus S, Bilde T, Tuni C. Resource availability, mating opportunity and sexual selection intensity influence the expression of male alternative reproductive tactics. J Evol Biol 2018; 31:1035-1046. [DOI: 10.1111/jeb.13284] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2017] [Revised: 03/12/2018] [Accepted: 04/09/2018] [Indexed: 11/29/2022]
Affiliation(s)
| | - Stano Pekár
- Department of Botany and Zoology; Masaryk University; Brno Czech Republic
| | - Magdalena Matzke
- Department of Biology; Ludwig-Maximilians University; Munich Germany
| | | | - Trine Bilde
- Department of Bioscience; Aarhus University; Aarhus Denmark
| | - Cristina Tuni
- Department of Biology; Ludwig-Maximilians University; Munich Germany
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21
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Beyer M, Czaczkes TJ, Tuni C. Does silk mediate chemical communication between the sexes in a nuptial feeding spider? Behav Ecol Sociobiol 2018. [DOI: 10.1007/s00265-018-2454-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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22
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Meade L, Harley E, Cotton A, Howie JM, Pomiankowski A, Fowler K. Variation in the benefits of multiple mating on female fertility in wild stalk-eyed flies. Ecol Evol 2017; 7:10103-10115. [PMID: 29238540 PMCID: PMC5723596 DOI: 10.1002/ece3.3486] [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: 08/17/2017] [Accepted: 09/04/2017] [Indexed: 01/22/2023] Open
Abstract
Polyandry, female mating with multiple males, is widespread across many taxa and almost ubiquitous in insects. This conflicts with the traditional idea that females are constrained by their comparatively large investment in each offspring, and so should only need to mate once or a few times. Females may need to mate multiply to gain sufficient sperm supplies to maintain their fertility, especially in species in which male promiscuity results in division of their ejaculate among many females. Here, we take a novel approach, utilizing wild-caught individuals to explore how natural variation among females and males influences fertility gains for females. We studied this in the Malaysian stalk-eyed fly species Teleopsis dalmanni. After an additional mating, females benefit from greatly increased fertility (proportion fertile eggs). Gains from multiple mating are not uniform across females; they are greatest when females have high fecundity or low fertility. Fertility gains also vary spatially, as we find an additional strong effect of the stream from which females were collected. Responses were unaffected by male mating history (males kept with females or in male-only groups). Recent male mating may be of lesser importance because males in many species, including T. dalmanni, partition their ejaculate to maintain their fertility over many matings. This study highlights the importance of complementing laboratory studies with data on wild-caught populations, where there is considerable heterogeneity between individuals. Future research should focus on environmental, demographic and genetic factors that are likely to significantly influence variation in individual female fecundity and fertility.
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Affiliation(s)
- Lara Meade
- Department of Genetics, Evolution and EnvironmentUniversity College LondonLondonUK
| | - Elisabeth Harley
- Department of Genetics, Evolution and EnvironmentUniversity College LondonLondonUK
| | - Alison Cotton
- Department of Genetics, Evolution and EnvironmentUniversity College LondonLondonUK
- CoMPLEXUniversity College LondonLondonUK
- Bristol Zoological SocietyBristol Zoo GardensCliftonBristolUK
| | - James M. Howie
- Department of Genetics, Evolution and EnvironmentUniversity College LondonLondonUK
| | - Andrew Pomiankowski
- Department of Genetics, Evolution and EnvironmentUniversity College LondonLondonUK
- CoMPLEXUniversity College LondonLondonUK
| | - Kevin Fowler
- Department of Genetics, Evolution and EnvironmentUniversity College LondonLondonUK
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23
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Toft S, Albo MJ. The shield effect: nuptial gifts protect males against pre-copulatory sexual cannibalism. Biol Lett 2017; 12:rsbl.2015.1082. [PMID: 27194284 DOI: 10.1098/rsbl.2015.1082] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 04/20/2016] [Indexed: 11/12/2022] Open
Abstract
Several not mutually exclusive functions have been ascribed to nuptial gifts across different taxa. Although the idea that a nuptial prey gift may protect the male from pre-copulatory sexual cannibalism is attractive, it has previously been considered of no importance based on indirect evidence and rejected by experimental tests. We reinvestigated whether nuptial gifts may function as a shield against female attacks during mating encounters in the spider Pisaura mirabilis and whether female hunger influences the likelihood of cannibalistic attacks. The results showed that pre-copulatory sexual cannibalism was enhanced when males courted without a gift and this was independent of female hunger. We propose that the nuptial gift trait has evolved partly as a counteradaptation to female aggression in this spider species.
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Affiliation(s)
- Søren Toft
- Department of Bioscience, Aarhus University, Aarhus 8000, Denmark
| | - Maria J Albo
- Department of Bioscience, Aarhus University, Aarhus 8000, Denmark Laboratorio de Etología, Ecología y Evolución, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay
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24
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Prokop P, Semelbauer M. Biometrical and behavioural associations with offering nuptial gifts by males in the spider Pisaura mirabilis. Anim Behav 2017. [DOI: 10.1016/j.anbehav.2017.05.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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25
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Albo MJ, Macías-Hernández N, Bilde T, Toft S. Mutual benefit from exploitation of female foraging motivation may account for the early evolution of gifts in spiders. Anim Behav 2017. [DOI: 10.1016/j.anbehav.2017.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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26
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Bürkli A, Jokela J. Increase in multiple paternity across the reproductive lifespan in a sperm-storing, hermaphroditic freshwater snail. Mol Ecol 2017; 26:5264-5278. [PMID: 28605149 DOI: 10.1111/mec.14200] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 06/01/2017] [Accepted: 06/02/2017] [Indexed: 12/28/2022]
Abstract
Polyandry is a common phenomenon and challenges the traditional view of stronger sexual selection in males than in females. In simultaneous hermaphrodites, the physical proximity of both sex functions was long thought to preclude the operation of sexual selection. Laboratory studies suggest that multiple mating and polyandry in hermaphrodites may actually be common, but data from natural populations are sparse. We therefore estimated the rate of multiple paternity and its seasonal variability in the annual, sperm-storing, simultaneously hermaphroditic freshwater snail Radix balthica for the entire duration of the reproductive lifespan. We also tested whether multiple paternity was associated with clutch size or embryonic development. To obtain these data, we measured and genotyped 60 field-collected egg clutches using nine highly polymorphic microsatellite markers. Overall, 50% of the clutches had multiple fathers, and both the frequency (20-93% of clutches) and magnitude of multiple paternity (mean 1.3-3.8 fathers per clutch) substantially increased over time, probably because of extensive sperm storage. Most multiply sired clutches (83%) had a dominant father, but neither clutch size nor the proportion of developed embryos per clutch was associated with levels of multiple paternity. Both the evident promiscuity and the frequent skew of paternity shares suggest that sexual selection may be an important evolutionary force in the study population.
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Affiliation(s)
- Anja Bürkli
- Department of Aquatic Ecology, EAWAG, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland.,ETH Zurich, D-USYS, Institute of Integrative Biology, Zürich, Switzerland
| | - Jukka Jokela
- Department of Aquatic Ecology, EAWAG, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland.,ETH Zurich, D-USYS, Institute of Integrative Biology, Zürich, Switzerland
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27
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Pandulli-Alonso I, Quaglia A, Albo MJ. Females of a gift-giving spider do not trade sex for food gifts: a consequence of male deception? BMC Evol Biol 2017; 17:112. [PMID: 28506206 PMCID: PMC5433081 DOI: 10.1186/s12862-017-0953-8] [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: 02/20/2017] [Accepted: 04/12/2017] [Indexed: 11/25/2022] Open
Abstract
Background Polyandry is commonly maintained by direct benefits in gift-giving species, so females may remate as an adaptive foraging strategy. However, the assumption of a direct benefit fades in mating systems where male gift-giving behaviour has evolved from offering nutritive to worthless (non-nutritive) items. In the spider Paratrechalea ornata, 70% of gifts in nature are worthless. We therefore predicted female receptivity to be independent of hunger in this species. We exposed poorly-fed and well-fed females to multiple males offering nutritive gifts and well-fed females to males offering worthless gifts. Results Though the treatments strongly affected fecundity, females of all groups had similar number of matings. This confirms that female receptivity is independent of their nutritional state, i.e. polyandry does not prevail as a foraging strategy. Conclusions In the spider Pisaura mirabilis, in which the majority (62%) of gifts in nature are nutritive, female receptivity depends on hunger. We therefore propose that the dependence of female receptivity on hunger state may have evolved in species with predominantly nutritive gifts but is absent in species with predominantly worthless gifts. Electronic supplementary material The online version of this article (doi:10.1186/s12862-017-0953-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Irene Pandulli-Alonso
- Laboratorio de Etología, Ecología y Evolución, Instituto de Investigaciones Biológicas Clemente Estable, Avenida Italia, 3318, Montevideo, Uruguay
| | - Agustín Quaglia
- Laboratorio de Arbovirus-Instituto de Virología "Dr. J. M. Vanella"-Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Maria J Albo
- Laboratorio de Etología, Ecología y Evolución, Instituto de Investigaciones Biológicas Clemente Estable, Avenida Italia, 3318, Montevideo, Uruguay.
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28
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Ghislandi PG, Beyer M, Velado P, Tuni C. Silk wrapping of nuptial gifts aids cheating behaviour in male spiders. Behav Ecol 2017. [DOI: 10.1093/beheco/arx028] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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29
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Boulton RA, Shuker DM. Polyandry is context dependent but not convenient in a mostly monandrous wasp. Anim Behav 2016. [DOI: 10.1016/j.anbehav.2015.12.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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30
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Boulton RA, Shuker DM. The costs and benefits of multiple mating in a mostly monandrous wasp. Evolution 2015; 69:939-49. [PMID: 25756346 PMCID: PMC4989449 DOI: 10.1111/evo.12636] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Accepted: 02/22/2015] [Indexed: 02/02/2023]
Abstract
The taxonomically widespread nature of polyandry remains a puzzle. Much of the empirical work regarding the costs and benefits of multiple mating to females has, for obvious reasons, relied on species that are already highly polyandrous. However, this makes it difficult to separate the processes that maintain the current level of polyandry from the processes that facilitate its expression and initiated its evolution. Here we consider the costs and benefits of polyandry in Nasonia vitripennis, a species of parasitoid wasp that is "mostly monandrous" in the wild, but which evolves polyandry under laboratory culture conditions. In a series of six experiments, we show that females gain a direct fecundity and longevity benefit from mating multiply with virgin males. Conversely, mating multiply with previously mated males actually results in a fecundity cost. Sexual harassment may also represent a significant cost of reproduction. Harassment was, however, only costly during oviposition, resulting in reduced fecundity, longevity, and disrupted sex allocation. Our results show that ecological changes, in our case associated with differences in the local mating structure in the laboratory can alter the costs and benefits of mating and harassment and potentially lead to shifts in mating patterns.
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