51
|
Engqvist L. Evolutionary Modeling Predicts a Decrease in Postcopulatory Sperm Viability as a Response to Increasing Levels of Sperm Competition. Am Nat 2012; 179:667-77. [DOI: 10.1086/665000] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
52
|
Shifferman EM. It's all in your head: the role of quantity estimation in sperm competition. Proc Biol Sci 2012; 279:833-40. [PMID: 22171084 PMCID: PMC3259941 DOI: 10.1098/rspb.2011.2256] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Accepted: 11/25/2011] [Indexed: 11/12/2022] Open
Abstract
The study of animal cognition has provided valuable data throughout the years, yet its reliance on laboratory work leaves some open questions. The main question is whether animals employ cognition in daily decision-making. The following discussion uses sperm competition (SC) as a test case for demonstrating the effect of cognition on routine choices, in this case, sexual selection. Cognition is manifested here by males' ability to represent the number of rivals competing with them. I claim that response to SC is driven by quantity estimation and the ability to assess competition magnitude cognitively. Hence, cognition can determine males' response to SC, and consequentially it can be selected within this context. This supports the argument that cognition constitutes an integral part of an individual's toolbox in solving real-life problems, and shows that physical and behavioural phenomena can expose cognition to selection and facilitate its evolution.
Collapse
Affiliation(s)
- Eran M Shifferman
- Konrad Lorenz Institute for Evolution and Cognition Research, Adolf Lorenz Gasse 2, 3422 Altenberg, Austria.
| |
Collapse
|
53
|
Tuni C, Berger-Tal R. Male preference and female cues: males assess female sexual maturity and mating status in a web-building spider. Behav Ecol 2012. [DOI: 10.1093/beheco/ars001] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
54
|
Dowling DK, Simmons LW. Ejaculate economics: testing the effects of male sexual history on the trade-off between sperm and immune function in Australian crickets. PLoS One 2012; 7:e30172. [PMID: 22253916 PMCID: PMC3256214 DOI: 10.1371/journal.pone.0030172] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Accepted: 12/14/2011] [Indexed: 11/30/2022] Open
Abstract
Trade-offs between investment into male sexual traits and immune function provide the foundation for some of the most prominent models of sexual selection. Post-copulatory sexual selection on the male ejaculate is intense, and therefore trade-offs should occur between investment into the ejaculate and the immune system. Examples of such trade-offs exist, including that between sperm quality and immunity in the Australian cricket, Teleogryllus oceanicus. Here, we explore the dynamics of this trade-off, examining the effects that increased levels of sexual interaction have on the viability of a male's sperm across time, and the concomitant effects on immune function. Males were assigned to a treatment, whereby they cohabited with females that were sexually immature, sexually mature but incapable of copulation, or sexually mature and capable of copulation. Sperm viability of each male was then assessed at two time points: six and 13 days into the treatment, and immune function at day 13. Sperm viability decreased across the time points, but only for males exposed to treatment classes involving sexually mature females. This decrease was similar in magnitude across both sexually mature classes, indicating that costs to the expression of high sperm viability are incurred largely through levels of pre-copulatory investment. Males exposed to immature females produced sperm of low viability at both time points. Although we confirmed a weak negative association between sperm viability and lytic activity (a measure of immune response to bacterial infection) at day 13, this relationship was not altered across the mating treatment. Our results highlight that sperm viability is a labile trait, costly to produce, and subject to strategic allocation in these crickets.
Collapse
Affiliation(s)
- Damian K Dowling
- School of Biological Sciences, Monash University, Clayton, Victoria, Australia.
| | | |
Collapse
|
55
|
Gress BE, Kelly CD. Is sperm viability independent of ejaculate size in the house cricket (Acheta domesticus)? CAN J ZOOL 2011. [DOI: 10.1139/z11-103] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Assessing sperm viability is a popular means of testing hypotheses related to ejaculate quality. This technique has produced interesting results; however, the sperm viability assay itself may kill sperm. This is a serious pitfall, as assay-related mortality could confound results and produce artificially low estimates of viability. To avoid spurious results, it has been recommended that investigators include sperm number in their viability analyses. Unfortunately, studies conducted to date on internal fertilizers have not included sperm counts in their analyses, so it is not possible to assess whether this factor can indeed produce artefactual results. In this paper, we use male house crickets ( Acheta domesticus (L., 1758)) to show that sperm viability is dependent on sperm number and exclusion of this factor from statistical analyses affects our interpretation of experimental treatment results. We show that mechanically rupturing a spermatophore significantly reduces sperm viability, but this does not appear to drive the nonindependent relationship between viability and number. Instead, our study shows that nonindependence is due to processes other than differential physical damage to the sperm during collection. We also show that allowing a spermatophore to evacuate its sperm without rupturing for 10 min maximizes both sperm number and viability.
Collapse
Affiliation(s)
- Brian E. Gress
- Department of Ecology, Evolution and Organismal Biology, Iowa State University, 339A Bessey Hall, Ames, IA 50011, USA
| | - Clint D. Kelly
- Department of Ecology, Evolution and Organismal Biology, Iowa State University, 339A Bessey Hall, Ames, IA 50011, USA
| |
Collapse
|
56
|
Allen LE, Barry KL, Holwell GI, Herberstein ME. Perceived risk of sperm competition affects juvenile development and ejaculate expenditure in male praying mantids. Anim Behav 2011. [DOI: 10.1016/j.anbehav.2011.09.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
57
|
Bonilla MM, Zeh DW, White AM, Zeh JA. Discriminating Males and Unpredictable Females: Males Bias Sperm Allocation in Favor of Virgin Females. Ethology 2011. [DOI: 10.1111/j.1439-0310.2011.01928.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
58
|
Delbarco-Trillo J. Adjustment of sperm allocation under high risk of sperm competition across taxa: a meta-analysis. J Evol Biol 2011; 24:1706-14. [PMID: 21569157 DOI: 10.1111/j.1420-9101.2011.02293.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Sperm competition theory predicts that under high risk of sperm competition, males will increase the number of sperm that they allocate to a female. This prediction has been supported by some experimental studies but not by others. Here, I conducted a meta-analysis to determine whether the increase in sperm allocation under high risk of sperm competition is a generalized response across taxa. I collected data from 39 studies and 37 species. Across taxa, males under a high risk of sperm competition respond by increasing their sperm allocation (mean effect size=0.32). Number of offspring did not explain a significant portion of the variation in effect sizes. A traditional meta-analysis (i.e. without phylogenetic information) described the variation among effect sizes better than a meta-analysis that incorporates the phylogenetic relationships among species, suggesting that the increase in sperm allocation under high risk of sperm competition is similarly prevalent across taxa.
Collapse
Affiliation(s)
- J Delbarco-Trillo
- Department of Evolutionary Anthropology, Duke University, Durham, NC, USA.
| |
Collapse
|
59
|
Slatyer RA, Mautz BS, Backwell PRY, Jennions MD. Estimating genetic benefits of polyandry from experimental studies: a meta-analysis. Biol Rev Camb Philos Soc 2011; 87:1-33. [PMID: 21545390 DOI: 10.1111/j.1469-185x.2011.00182.x] [Citation(s) in RCA: 175] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Rachel A Slatyer
- Evolution, Ecology & Genetics, Research School of Biology, The Australian National University, Canberra, Australia
| | | | | | | |
Collapse
|
60
|
Simmons LW, Beveridge M. Seminal fluid affects sperm viability in a cricket. PLoS One 2011; 6:e17975. [PMID: 21455309 PMCID: PMC3063794 DOI: 10.1371/journal.pone.0017975] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2010] [Accepted: 02/17/2011] [Indexed: 11/17/2022] Open
Abstract
Recent studies have suggested that males may vary the quality of their ejaculates in response to sperm competition, although the mechanisms by which they do so remain unclear. The viability of sperm is an important aspect of ejaculate quality that determines competitive fertilization success in the field cricket Teleogryllus oceanicus. Using in vitro mixtures of sperm and seminal fluid from pairs of male crickets, we show that seminal fluid can affect the viability of sperm in this species. We found that males who invest greatly in the viability of their own sperm can enhance the viability of rival sperm, providing the opportunity for males to exploit the investments in sperm competition made by their rivals. Transitive effects of seminal fluids across the ejaculates of different males are expected to have important implications for the dynamics of male investments in sperm competition.
Collapse
Affiliation(s)
- Leigh W Simmons
- School of Animal Biology, Centre for Evolutionary Biology, The University of Western Australia, Crawley, Australia.
| | | |
Collapse
|
61
|
Kelly CD, Jennions MD. Sexual selection and sperm quantity: meta-analyses of strategic ejaculation. Biol Rev Camb Philos Soc 2011; 86:863-84. [PMID: 21414127 DOI: 10.1111/j.1469-185x.2011.00175.x] [Citation(s) in RCA: 214] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Clint D Kelly
- Department of Ecology, Evolution & Organismal Biology, Iowa State University, Ames, USA.
| | | |
Collapse
|
62
|
Klaus SP, Fitzsimmons LP, Pitcher TE, Bertram SM. Song and Sperm in Crickets: A Trade-off between Pre- and Post-copulatory Traits or Phenotype-Linked Fertility? Ethology 2010. [DOI: 10.1111/j.1439-0310.2010.01857.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
63
|
Lupold S, Manier MK, Ala-Honkola O, Belote JM, Pitnick S. Male Drosophila melanogaster adjust ejaculate size based on female mating status, fecundity, and age. Behav Ecol 2010. [DOI: 10.1093/beheco/arq193] [Citation(s) in RCA: 130] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
64
|
Drayton JM, Milner RNC, Hall MD, Jennions MD. Inbreeding and courtship calling in the cricket Teleogryllus commodus. J Evol Biol 2010; 24:47-58. [PMID: 21054622 DOI: 10.1111/j.1420-9101.2010.02135.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- J M Drayton
- Evolution, Ecology & Genetics, Research School of Biology, The Australian National University, Canberra, ACT, Australia.
| | | | | | | |
Collapse
|
65
|
Simmons LW, Tinghitella RM, Zuk M. Quantitative genetic variation in courtship song and its covariation with immune function and sperm quality in the field cricket Teleogryllus oceanicus. Behav Ecol 2010. [DOI: 10.1093/beheco/arq154] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
|
66
|
Simmons LW, Beveridge M. The strength of postcopulatory sexual selection within natural populations of field crickets. Behav Ecol 2010. [DOI: 10.1093/beheco/arq132] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
|
67
|
THOMAS MELISSAL, SIMMONS LEIGHW. Cuticular hydrocarbons influence female attractiveness to males in the Australian field cricket,Teleogryllus oceanicus. J Evol Biol 2010; 23:707-14. [DOI: 10.1111/j.1420-9101.2010.01943.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
68
|
|
69
|
Wada T, Takegaki T, Mori T, Natsukari Y. Sperm removal, ejaculation and their behavioural interaction in male cuttlefish in response to female mating history. Anim Behav 2010. [DOI: 10.1016/j.anbehav.2009.12.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
70
|
The role of chemical communication in sexual selection: hair-pencil displays in the diamondback moth, Plutella xylostella. Anim Behav 2010. [DOI: 10.1016/j.anbehav.2009.11.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
71
|
Bretman A, Fricke C, Hetherington P, Stone R, Chapman T. Exposure to rivals and plastic responses to sperm competition in Drosophila melanogaster. Behav Ecol 2010. [DOI: 10.1093/beheco/arp189] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
72
|
Dziminski MA, Roberts JD, Simmons LW. Sperm morphology, motility and fertilisation capacity in the myobatrachid frog Crinia georgiana. Reprod Fertil Dev 2010; 22:516-22. [DOI: 10.1071/rd09124] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2009] [Accepted: 09/10/2009] [Indexed: 11/23/2022] Open
Abstract
Sperm traits have been found to vary between individuals within populations in a variety of taxa. Sperm motility, morphometry and viability may be expected to have important effects on male fertility, although previous studies have found varying patterns, especially in external fertilisers. In the present study, we examined the effects of sperm swimming velocity, the proportion of motile spermatozoa, sperm head and tail length and the proportion of live spermatozoa on fertilisation success in the externally fertilising myobatrachid frog Crinia georgiana using IVF techniques and by controlling sperm numbers. We found no effect of any of the sperm traits we measured on IVF success. Neither did we find any relationship between sperm morphology and sperm performance. There was a negative relationship between sperm viability and male body size, which could be a function of age or an alternative tactic of differential investment in spermatozoa by smaller-sized males using sneak tactics in multiple matings. In contrast with most externally fertilising aquatic organisms, high rates of fertilisation appear to be achieved in C. georgiana with relatively low sperm swimming speeds.
Collapse
|
73
|
|
74
|
BRETMAN AMANDA, NEWCOMBE DEVI, TREGENZA TOM. Promiscuous females avoid inbreeding by controlling sperm storage. Mol Ecol 2009; 18:3340-5. [DOI: 10.1111/j.1365-294x.2009.04301.x] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
75
|
Thomas ML, Simmons LW. Male dominance influences pheromone expression, ejaculate quality, and fertilization success in the Australian field cricket, Teleogryllus oceanicus. Behav Ecol 2009. [DOI: 10.1093/beheco/arp105] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
76
|
Cornwallis CK, O'Connor EA. Sperm: seminal fluid interactions and the adjustment of sperm quality in relation to female attractiveness. Proc Biol Sci 2009; 276:3467-75. [PMID: 19586951 PMCID: PMC2817187 DOI: 10.1098/rspb.2009.0807] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
An important predictor of male fitness is the fertilizing efficiency of their ejaculates. Ejaculates are costly to produce and males are predicted to devote greater resources to copulations with reproductively superior females. It is well established that males allocate different numbers of sperm to ejaculates. However, less is known about how males adjust their sperm quality, which has important implications for our understanding of fertilization and the evolution of sexual strategies. Here we test in the fowl, Gallus gallus, whether males adjust their sperm velocity by differentially allocating seminal fluid to copulations with attractive and unattractive females. To disentangle the contributions of sperm and seminal fluid to sperm velocity, we separated and remixed sperm and seminal fluid from ejaculates allocated to females of different attractiveness. We show that dominant males increase the velocity of the sperm they invest in more attractive females by allocating larger ejaculates that contain seminal fluid that increases sperm velocity. Furthermore, we find weak evidence that males also allocate sperm with higher velocity, irrespective of seminal fluid, to more attractive females.
Collapse
Affiliation(s)
- Charlie K Cornwallis
- Edward Grey Institute, Department of Zoology, University of Oxford, Oxford OX1 3PS, UK.
| | | |
Collapse
|
77
|
|
78
|
den Boer SPA, Boomsma JJ, Baer B. Honey bee males and queens use glandular secretions to enhance sperm viability before and after storage. JOURNAL OF INSECT PHYSIOLOGY 2009; 55:538-543. [PMID: 19232404 DOI: 10.1016/j.jinsphys.2009.01.012] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2008] [Revised: 01/13/2009] [Accepted: 01/23/2009] [Indexed: 05/27/2023]
Abstract
Internal fertilization requires live sperm to be transferred from male to female before egg fertilization. Both males and females assist the insemination process by providing sperm with glandular secretions, which have been inferred to contain subsets of proteins that maintain sperm viability. Here we show that in the honeybee (Apis mellifera) secretions of the male accessory glands, the major contributors towards seminal fluid, enhance sperm survival. We further demonstrate that the protein fraction of the male accessory gland secretion is indeed important for achieving the maximal effect on sperm survival. After sperm storage, the queens also provide sperm with secretions from spermathecal glands and we show that these secretions have a comparable positive effect on sperm viability. SDS gels show that the proteomic profiles of accessory gland secretion and spermathecal fluid secretion hardly overlap, which suggests that males and females use different proteins to enhance sperm viability during, respectively, ejaculation and final sperm storage.
Collapse
Affiliation(s)
- Susanne P A den Boer
- Centre for Social Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
| | | | | |
Collapse
|
79
|
|
80
|
Heubel KU, Rankin DJ, Kokko H. How to go extinct by mating too much: population consequences of male mate choice and efficiency in a sexual-asexual species complex. OIKOS 2009. [DOI: 10.1111/j.1600-0706.2008.17024.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
81
|
Evans JP. No evidence for sperm priming responses under varying sperm competition risk or intensity in guppies. Naturwissenschaften 2009; 96:771-9. [DOI: 10.1007/s00114-009-0529-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2009] [Revised: 03/10/2009] [Accepted: 03/10/2009] [Indexed: 10/21/2022]
|
82
|
Thomas ML, Simmons LW. Male-derived cuticular hydrocarbons signal sperm competition intensity and affect ejaculate expenditure in crickets. Proc Biol Sci 2009; 276:383-8. [PMID: 18854298 DOI: 10.1098/rspb.2008.1206] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Female sexual promiscuity can have significant effects on male mating decisions because it increases the intensity of competition between ejaculates for fertilization. Because sperm production is costly, males that can detect multiple matings by females and allocate sperm strategically will have an obvious fitness advantage. The presence of rival males is widely recognized as a cue used by males to assess sperm competition. However, for species in which males neither congregate around nor guard females, other more cryptic cues might be involved. Here, we demonstrate unprecedented levels of sperm competition assessment by males, which is mediated via the use of chemical cues. Using the cricket Teleogryllus oceanicus, we manipulated male perception of sperm competition by experimentally coating live unmated females with cuticular compounds extracted from males. We found that males adjusted their ejaculate allocation in response to these compounds: the viability of sperm contained within a male's ejaculate decreased as the number of male extracts applied to his virgin female partner was increased. We further show that males do not respond to the relative concentration of male compounds present on females, but rather to the number of distinct signature odours of individual males. Our results conform to sperm competition theory, and show for the first time, to our knowledge, that males can detect different intensities of sperm competition by using distinct chemical cues of individual males present on females.
Collapse
Affiliation(s)
- Melissa L Thomas
- Centre for Evolutionary Biology, School of Animal Biology, The University of Western Australia, Crawley, Western Australia 6009, Australia.
| | | |
Collapse
|
83
|
Wong BBM, McCarthy M. Prudent male mate choice under perceived sperm competition risk in the eastern mosquito fish. Behav Ecol 2009. [DOI: 10.1093/beheco/arp010] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
84
|
Guevara-Fiore P, Skinner A, Watt P. Do male guppies distinguish virgin females from recently mated ones? Anim Behav 2009. [DOI: 10.1016/j.anbehav.2008.10.018] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
85
|
Male monarch butterflies, Danaus plexippus, adjust ejaculates in response to intensity of sperm competition. Anim Behav 2009. [DOI: 10.1016/j.anbehav.2008.10.026] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
86
|
Heubel KU, Schlupp I. Seasonal plasticity in male mating preferences in sailfin mollies. Behav Ecol 2008. [DOI: 10.1093/beheco/arn105] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
87
|
Abstract
Previous studies of the cricket Teleogryllus oceanicus have shown a paternity bias towards non-sibling males. Although non-kin-biased paternity could represent a mechanism of postcopulatory inbreeding avoidance by females, evolutionarily stable strategy (ESS) models of ejaculate evolution also predict that males should reduce their expenditure on the ejaculate when mating with their sisters. Here we provide a test of these models, finding that male crickets invest equally in matings with full-siblings, half-siblings and non-sibling females. The data suggest that in this species, males and females differ in their response to inbreeding.
Collapse
Affiliation(s)
- Leigh W Simmons
- Centre for Evolutionary Biology, School of Animal Biology (M092), The University of Western Australia, Crawley, Western Australia 6009, Australia.
| | | |
Collapse
|
88
|
|
89
|
Thomas ML, Simmons LW. Sexual dimorphism in cuticular hydrocarbons of the Australian field cricket Teleogryllus oceanicus (Orthoptera: Gryllidae). JOURNAL OF INSECT PHYSIOLOGY 2008; 54:1081-1089. [PMID: 18519139 DOI: 10.1016/j.jinsphys.2008.04.012] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2008] [Revised: 04/10/2008] [Accepted: 04/15/2008] [Indexed: 05/26/2023]
Abstract
Sexual dimorphism is presumed to reflect adaptive divergence in response to selection favouring different optimal character states in the two sexes. Here, we analyse patterns of sexual dimorphism in the cuticular hydrocarbons of the Australian field cricket Teleogryllus oceanicus using gas chromatography. Ten of the 25 peaks found in our chromatographs, differed in their relative abundance between the sexes. The presence of sexual dimorphism in T. oceanicus is discussed in reference to a review of sexual dimorphism in cuticular hydrocarbons of other insects. We found that this trait has been examined in 103 species across seven different orders. Seventy-six of these species (73%) displayed sex specificity of cuticular hydrocarbons, the presence/absence of which does not appear to be directly linked to phylogeny. The occurrence of sexual dimorphism in cuticular hydrocarbons of some but not other species, and the extent of variation within genera, suggest that this divergence has been driven primarily by sexual selection.
Collapse
Affiliation(s)
- Melissa L Thomas
- Centre for Evolutionary Biology, School of Animal Biology, The University of Western Australia, Australia.
| | | |
Collapse
|
90
|
Thomas ML, Simmons LW. Rival male relatedness does not affect ejaculate allocation as predicted by sperm competition theory. PLoS One 2008; 3:e2151. [PMID: 18478102 PMCID: PMC2364655 DOI: 10.1371/journal.pone.0002151] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2008] [Accepted: 03/20/2008] [Indexed: 11/21/2022] Open
Abstract
When females are sexually promiscuous, the intensity of sperm competition for males depends on how many partners females mate with. To maximize fitness, males should adjust their copulatory investment in relation to this intensity. However, fitness costs associated with sperm competition may not only depend on how many males a female has mated with, but also how related rival males are. According to theoretical predictions, males should adjust their copulatory investment in response to the relatedness of their male rival, and transfer more sperm to females that have first mated with a non-sibling male than females that have mated to a related male. Here, for the first time, we empirically test this theory using the Australian field cricket Teleogryllus oceanicus. We expose male crickets to sperm competition from either a full sibling or non-sibling male, by using both the presence of a rival male and the rival male's actual competing ejaculate as cues. Contrary to predictions, we find that males do not adjust ejaculates in response to the relatedness of their male rival. Instead, males with both full-sibling and non-sibling rivals allocate sperm of similar quality to females. This lack of kin biased behaviour is independent of any potentially confounding effect of strong competition between close relatives; kin biased behaviour was absent irrespective of whether males were raised in full sibling or mixed relatedness groups.
Collapse
Affiliation(s)
- Melissa L Thomas
- Centre for Evolutionary Biology, School of Animal Biology, The University of Western Australia, Crawley, Australia.
| | | |
Collapse
|
91
|
Rönn JL, Katvala M, Arnqvist G. Interspecific variation in ejaculate allocation and associated effects on female fitness in seed beetles. J Evol Biol 2008; 21:461-70. [PMID: 18205778 DOI: 10.1111/j.1420-9101.2007.01493.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
When ejaculates are costly to produce, males are expected to allocate their ejaculate resources over successive matings in a manner that optimizes their reproductive success and this may have important consequences for their mates. In seed beetles (Coleoptera; Bruchidae), ejaculates vary in size across species from weighing less than 1%, up to as much as 8%, of male body weight. Ejaculates contain not only sperm but also a range of additional substances and females in some species gain benefits from receiving large ejaculates. Male ejaculate allocation may thus affect female fitness. Here, we first characterized the pattern of male ejaculate allocation over successive matings in seven-seed beetle species. We then assessed how this allocation affected female fitness in each species. Although females generally benefited from receiving large ejaculates, the interspecific variation observed both in ejaculate allocation patterns and in their effects on female fitness was remarkably large considering that the species studied are closely related. Our analyses suggest that variation in ejaculate composition is the key, both within and across species. We discuss possible causes for this variation and conclude that coevolution between male ejaculates and female utilization of ejaculate substances has apparently been rapid in this clade.
Collapse
Affiliation(s)
- J L Rönn
- Evolutionary Biology Centre, Department of Animal Ecology, Uppsala University, Sweden
| | | | | |
Collapse
|
92
|
Simmons LW, Denholm A, Jackson C, Levy E, Madon E. Male crickets adjust ejaculate quality with both risk and intensity of sperm competition. Biol Lett 2007; 3:520-2. [PMID: 17686757 PMCID: PMC2391201 DOI: 10.1098/rsbl.2007.0328] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Sperm competition theory predicts that males should increase their expenditure on the ejaculate with increasing risk of sperm competition, but decrease their expenditure with increasing intensity. There is accumulating evidence for sperm competition theory, based on examinations of testes size and/or the numbers of sperm ejaculated. However, recent studies suggest that ejaculate quality can also be subject to selection by sperm competition. We used experimental manipulations of the risk and intensity of sperm competition in the cricket, Teleogryllus oceanicus. We found that males produced ejaculates with a greater percentage of live sperm when they had encountered a rival male prior to mating. However, when mating with a female that presented a high intensity of sperm competition, males did not respond to risk, but produced ejaculates with a reduced percentage of live sperm. Our data suggest that males exhibit a fine-tuned hierarchy of responses to these cues of sperm competition.
Collapse
Affiliation(s)
- Leigh W Simmons
- Centre for Evolutionary Biology, School of Animal Biology (M092), The University of Western Australia, Crawley, Western Australia 6009, Australia.
| | | | | | | | | |
Collapse
|