1
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Eberhard WG, Gelhaus JK. Stimulatory Functions of Male Genitalia in Tipula ( Triplicitipula) colei Alexander and Tipula ( Lunatipula) translucida Doane (Diptera: Tipulidae) and Implications for Theories of Genital Evolution. INSECTS 2024; 15:680. [PMID: 39336648 PMCID: PMC11432625 DOI: 10.3390/insects15090680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2024] [Revised: 08/30/2024] [Accepted: 09/04/2024] [Indexed: 09/30/2024]
Abstract
Male genitalia have been hypothesized to function as courtship devices during copulation, but it is difficult to use behavioral observations to test this hypothesis because male genitalia are usually hidden inside the female during copulation. In tipuloid flies, however, nearly all of the male's complex genital structures remain outside the female. Copulation behavior and genital morphology in Tipula (Triplicitipula) colei and T. (Lunatipula) translucida suggest that some male genital structures function to stimulate the female: male structures that contact the female bear tufts or dense arrays of modified setae on precisely the surfaces that contact the female; contact involves repeated, stereotyped rhythmic movements that include brushing, vibrating, scraping, and tapping; the movements are appropriately designed to utilize the morphology of the modified setae to stimulate the female; and the movements have little or no other perceptible mechanical effects on the female. The female structures contacted by these male genital movements fail to show the defensive designs predicted by the theories of genital evolution that are based on morphological species isolation or male-female morphological conflicts of interest; also unexplained by the conflict of interest hypothesis are female movements that seem designed to increase rather than avoid stimulation by the male.
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Affiliation(s)
- William G. Eberhard
- Smithsonian Tropical Research Institute and Escuela de Biología, Universidad de Costa Rica, Ciudad Universitaria, Costa Rica, and Museum of Natural Science, Louisiana State University, Baton Rouge, LA 70808, USA
| | - Jon K. Gelhaus
- Department of Biodiversity, Earth and Environmental Sciences, The Academy of Natural Sciences, Drexel University, 1900 Ben Franklin Parkway, Philadelphia, PA 19103-1195, USA;
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2
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Somjee U, Marting P, Anzaldo S, Simmons LW, Painting CJ. Extreme range in adult body size reveals hidden trade-offs among sexually selected traits. Evolution 2024; 78:1382-1395. [PMID: 38900629 DOI: 10.1093/evolut/qpae084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2023] [Revised: 05/13/2024] [Accepted: 05/24/2024] [Indexed: 06/22/2024]
Abstract
Sexually selected weapons used to monopolize mating opportunities are predicted to trade-off with traits used in competition for fertilization. Yet, the limited size range typically found among adults of a species often precludes clear comparisons between population-level and individual-level relative trait investment. The jousting weevil, Brentus anchorago (Coleoptera: Brentidae), varies more than 26-fold in body mass, which is among the most extreme adult body size ranges of any solitary terrestrial species. We reveal a trade-off at a population level: hypermetric scaling in male weapons (slope = 1.59) and a closely mirrored reversal in allocation to postcopulatory traits (slope = 0.54). Yet, at the individual level, we find the opposite pattern; males that invest relatively more in weapons for their size class also invest more in postcopulatory traits. Across 36 dung beetle and 41 brentine weevil species, we find the allometric slope explains more trait variation at larger body size ranges; in brentines, population-level scaling patterns become more detectable in species with a larger range in adult body size. Our findings reveal that population-level allometries and individual-level trade-offs can both be important in shaping relative trait allocation; we highlight that the adult body size range is rarely examined but may be integral to gaining a deeper understanding of trade-offs in reproductive allocation.
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Affiliation(s)
- Ummat Somjee
- Department of Integrative Biology, University of Texas, Austin, TX, United States
- Smithsonian Tropical Research Institute, Balboa, Panama
| | - Peter Marting
- Department of Biological Sciences, Auburn University, Auburn, AL, United States
| | - Salvatore Anzaldo
- School of Life Sciences, Arizona State University, Tempe, AZ, United States
| | - Leigh W Simmons
- School of Biological Sciences, University of Western Australia, Perth, WA, Australia
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3
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Cupello M, Ribeiro-Costa CS, Vaz-De-Mello FZ. The evolution of Bolbites onitoides (Coleoptera: Scarabaeidae: Phanaeini): its phylogenetic significance, geographical polychromatism and the subspecies problem. Zool J Linn Soc 2021. [DOI: 10.1093/zoolinnean/zlab015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
The distribution of the iridescent dung beetle Bolbites onitoides can be divided, based on dorsal colouration, into a blue western-half and a red eastern-half. This has raised the question, in 1959, of whether the two colour variants could represent distinct subspecies. Having examined ~1200 specimens and evaluated the proposal under both an ontological and an operational subspecies concept, we conclude that B. onitoides should continue to be treated as a single monotypic species because: (1) two kinds of colour intermediates were found living among populations of the two main variants; (2) the distribution of the variants overlaps; (3) no other characters were seen to vary consistently in accordance with the colour variants; (4) the overall geographical pattern can be explained by phenomena other than (incipient) speciation, such as phenotypic plasticity and distinct selective regimes; and (5) colour has been extensively shown not to be a reliable indicator of speciation processes among dung beetles. By comparing our findings with other cases of polychromatism among scarabaeines, we discuss publications proposing subspecies taxa relying uniquely upon colour variants. We contend that, due to the often continuous, populational, polytopic and, several times, clinal nature of the intraspecific geographical variation, subspecies classification schemes should not be established simply to classify variation across a species range without a commitment to the reality as evolutionary entities of the taxa being proposed. The alternative stance championed by many contemporary authors to give trinomina to conspecific (meta)population lineages, in turn, may eventually prove to be adequate, but we express some of our concerns as to the feasibility of this practice. Whether these intraspecific taxa should be ranked in a Linnaean hierarchy – e.g. as subspecies – is equally an open question. We also elaborate on an evolutionary scenario where the role of the iridescence in sexual selection, as hypothesized in a previous work, may be an exaptation, not an adaptation, among the horned Phanaeina.
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Affiliation(s)
- Mario Cupello
- Universidade Federal do Paraná, Departamento de Zoologia, Laboratório de Sistemática e Bioecologia de Coleoptera. Centro Politécnico, Jardim das Américas, CEP 81.531-980, Curitiba, PR, Brazil
- Fellow of the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
| | - Cibele S Ribeiro-Costa
- Universidade Federal do Paraná, Departamento de Zoologia, Laboratório de Sistemática e Bioecologia de Coleoptera. Centro Politécnico, Jardim das Américas, CEP 81.531-980, Curitiba, PR, Brazil
- Fellow of the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
| | - Fernando Z Vaz-De-Mello
- Universidade Federal de Mato Grosso, Instituto de Biociências, Departamento de Biologia e Zoologia. Av. Fernando Correa da Costa, 2367, Boa Esperança, 78.060-900, Cuiabá, MT, Brazil
- Fellow of the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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4
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Wylde Z, Bonduriansky R. Condition dependence of phenotypic integration and the evolvability of genitalic traits in a neriid fly. Biol Lett 2020; 16:20200124. [PMID: 32453964 DOI: 10.1098/rsbl.2020.0124] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The spectacular diversity of insect male genitalia, and their relative insensitivity to the environment, have long puzzled evolutionary biologists and taxonomists. We asked whether the unusual evolvability of male genitalia could be associated with low morphological integration of genitalic traits, by comparison with male somatic traits and female traits. We also asked whether this pattern was robust to variation in resource availability during development, which affects adult condition. To address these questions, we manipulated larval diet quality in a split-brood design and compared levels of integration of male and female genitalic and somatic traits in the neriid fly, Telostylinus angusticollis. We found that male genitalic traits were substantially less integrated than male somatic traits, and less integrated than female genitalic traits. Female genitalic traits were also less integrated than female somatic traits, but the difference was less pronounced than in males. However, integration of male genitalic traits was negatively condition-dependent, with high-condition males exhibiting lower trait integration than low-condition males. Finally, genitalic traits exhibited lower larval diet × family interactions than somatic traits. These results could help explain the unusually high evolvability of male genitalic traits in insects.
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Affiliation(s)
- Zachariah Wylde
- Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia
| | - Russell Bonduriansky
- Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia
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5
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House C, Tunstall P, Rapkin J, Bale MJ, Gage M, Del Castillo E, Hunt J. Multivariate stabilizing sexual selection and the evolution of male and female genital morphology in the red flour beetle. Evolution 2020; 74:883-896. [PMID: 31889313 PMCID: PMC7317928 DOI: 10.1111/evo.13912] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 12/11/2019] [Accepted: 12/15/2019] [Indexed: 11/28/2022]
Abstract
Male genitals are highly divergent in animals with internal fertilization. Most studies attempting to explain this diversity have focused on testing the major hypotheses of genital evolution (the lock‐and‐key, pleiotropy, and sexual selection hypotheses), and quantifying the form of selection targeting male genitals has played an important role in this endeavor. However, we currently know far less about selection targeting female genitals or how male and female genitals interact during mating. Here, we use formal selection analysis to show that genital size and shape is subject to strong multivariate stabilizing sexual selection in both sexes of the red flour beetle, Tribolium castaneum. Moreover, we show significant sexual selection on the covariance between the sexes for specific aspects of genital shape suggesting that male and female genitalia also interact to determine the successful transfer of a spermatophore during mating. Our work therefore highlights the important role that both male and female genital morphologies play in determining mating success and that these effects can occur independently, as well as through their interaction. Moreover, it cautions against the overly simplistic view that the sexual selection targeting genital morphology will always be directional in form and restricted primarily to males.
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Affiliation(s)
- Clarissa House
- School of Science and Health and Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, 2753, Australia
| | - Philip Tunstall
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Cornwall, TR10 9EZ, United Kingdom
| | - James Rapkin
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Cornwall, TR10 9EZ, United Kingdom
| | - Mathilda J Bale
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Cornwall, TR10 9EZ, United Kingdom
| | - Matthew Gage
- School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, United Kingdom
| | - Enrique Del Castillo
- Department of Industrial Engineering and Department of Statistics, Pennsylvania State University, State College, Pennsylvania, 16802
| | - John Hunt
- School of Science and Health and Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW, 2753, Australia.,Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Cornwall, TR10 9EZ, United Kingdom
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6
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Nunes RV, Vaz-de-Mello FZ. Taxonomic revision ofDichotomius (Cephagonus)Luederwaldt 1929 and the taxonomic status of remainingDichotomiusHope 1838 subgenera (Coleoptera: Scarabaeidae: Scarabaeinae: Dichotomiini). J NAT HIST 2020. [DOI: 10.1080/00222933.2019.1692088] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Rafael V. Nunes
- Instituto de Biociências, Departamento de Biologia e Zoologia, Coleção Entomológica, Universidade Federal de Mato Grosso, Cuiabá, Brasil
| | - Fernando Z. Vaz-de-Mello
- Instituto de Biociências, Departamento de Biologia e Zoologia, Coleção Entomológica, Universidade Federal de Mato Grosso, Cuiabá, Brasil
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7
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Zhou YL, Zhou HZ, Ślipiński A, Beutel RG. Evolution of a hyper-complex intromittent organ in rove beetles – the endophallus of Xantholinini (Staphylinidae: Coleoptera). Zool J Linn Soc 2019. [DOI: 10.1093/zoolinnean/zlz116] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
Studies on the functional morphology and evolution of genitalia have been crucial to understanding sexual traits in speciation, reproductive isolation and sexual selection in Coleoptera and insects in general. However, the focus of investigation of the intromittent organ of beetles was largely confined to the sclerotized elements of the aedeagus, whereas the membranous structures of the endophallus (=internal sac) have often not been adequately considered. Using a micro-operating technique, we observed living male rove beetles and found five different types of endophallus eversion and related morphological modifications. Analysing genital data of a larger sample of Xantholinini, we could demonstrate that endophallus complexity and modifications tend to vary inversely with the median lobe (penis: intromittent organ). Our comparative morphological study, combined with a molecular phylogenetic analysis, suggests that endophallus spiralling occurring after endophallus eversion is an innovation in beetle evolution.
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Affiliation(s)
- Yu-Lingzi Zhou
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Chaoyang District, Beijing, P. R. China
- Australian National Insect Collection, National Research Collections Australia, Commonwealth Scientific and Industrial Research Organisation, Canberra, ACT, Australia
| | - Hong-Zhang Zhou
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Chaoyang District, Beijing, P. R. China
| | - Adam Ślipiński
- Australian National Insect Collection, National Research Collections Australia, Commonwealth Scientific and Industrial Research Organisation, Canberra, ACT, Australia
| | - Rolf G Beutel
- Institut für Zoologie und Evolutionsforschung, Friedrich-Schiller-Universität Jena, Jena, Germany
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8
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Eberhard WG, Lehmann GUC. Demonstrating sexual selection by cryptic female choice on male genitalia: What is enough? Evolution 2019; 73:2415-2435. [PMID: 31599962 DOI: 10.1111/evo.13863] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 09/17/2019] [Accepted: 09/27/2019] [Indexed: 01/07/2023]
Abstract
Rapid divergence in external genital structures occurs in nearly all animal groups that practice internal insemination; explaining this pattern is a major challenge in evolutionary biology. The hypothesis that species-specific differences in male genitalia evolved under sexual selection as courtship devices to influence cryptic female choice (CFC) has been slow to be accepted. Doubts may stem from its radical departure from previous ideas, observational difficulties because crucial events occur hidden within the female's body, and alternative hypotheses involving biologically important phenomena such as speciation, sperm competition, and male-female conflicts of interest. We assess the current status of the CFC hypothesis by reviewing data from two groups in which crucial predictions have been especially well-tested, Glossina tsetse flies and Roeseliana (formerly Metrioptera) roeselii bushcrickets. Eighteen CFC predictions have been confirmed in Glossina and 19 in Roeseliana. We found data justifying rejection of alternative hypotheses, but none that contradicted CFC predictions. The number and extent of tests confirming predictions of the CFC hypothesis in these species is greater than that for other generally accepted hypotheses regarding the functions of nongenital structures. By this criterion, it is reasonable to conclude that some genital structures in both groups likely involved sexual selection by CFC.
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Affiliation(s)
- William G Eberhard
- Smithsonian Tropical Research Institute, Universidad de Costa Rica, and Museum of Natural Science, Louisiana State University, Baton Rouge, Louisiana, 70803
| | - Gerlind U C Lehmann
- Evolutionary Ecology, Department of Biology, Humboldt University Berlin, 10117, Berlin, Germany
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9
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Sloan NS, Simmons LW. The evolution of female genitalia. J Evol Biol 2019; 32:882-899. [PMID: 31267594 DOI: 10.1111/jeb.13503] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 06/14/2019] [Accepted: 06/21/2019] [Indexed: 02/07/2023]
Abstract
Female genitalia have been largely neglected in studies of genital evolution, perhaps due to the long-standing belief that they are relatively invariable and therefore taxonomically and evolutionarily uninformative in comparison with male genitalia. Contemporary studies of genital evolution have begun to dispute this view, and to demonstrate that female genitalia can be highly diverse and covary with the genitalia of males. Here, we examine evidence for three mechanisms of genital evolution in females: species isolating 'lock-and-key' evolution, cryptic female choice and sexual conflict. Lock-and-key genital evolution has been thought to be relatively unimportant; however, we present cases that show how species isolation may well play a role in the evolution of female genitalia. Much support for female genital evolution via sexual conflict comes from studies of both invertebrate and vertebrate species; however, the effects of sexual conflict can be difficult to distinguish from models of cryptic female choice that focus on putative benefits of choice for females. We offer potential solutions to alleviate this issue. Finally, we offer directions for future studies in order to expand and refine our knowledge surrounding female genital evolution.
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Affiliation(s)
- Nadia S Sloan
- Centre for Evolutionary Biology, School of Biological Sciences (M092), The University of Western Australia, Crawley, Western Australia, Australia
| | - Leigh W Simmons
- Centre for Evolutionary Biology, School of Biological Sciences (M092), The University of Western Australia, Crawley, Western Australia, Australia
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10
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Buzatto BA, Kotiaho JS, Assis LAF, Simmons LW. A link between heritable parasite resistance and mate choice in dung beetles. Behav Ecol 2019. [DOI: 10.1093/beheco/arz089] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
AbstractParasites play a central role in the adaptiveness of sexual reproduction. Sexual selection theory suggests a role for parasite resistance in the context of mate choice, but the evidence is mixed. The parasite-mediated sexual selection (PMSS) hypothesis derives a number of predictions, among which that resistance to parasites is heritable, and that female choice favors parasite resistance genes in males. Here, we tested the PMSS hypothesis using the dung beetle Onthophagus taurus, a species that can be heavily parasitized by Macrocheles merdarius mites, which are known to affect adult survival. We investigated the heritability of resistance to M. merdarius, as well as whether female O. taurus impose a mating bias against males susceptible to mite infestation. Female choice for parasite resistance is difficult to disentangle from the possibility that females are simply choosing less parasitized males due to naturally selected benefits of avoiding contracting those parasites. This is especially likely for ectoparasites, such as mites. We tackled this problem by performing a mate choice trial first, and then measuring a male’s resistance to mite infestation. Resistance to mite infestation exhibited significant levels of additive genetic variance. Although we found no relationship between mating success and parasite resistance, males with greater resistance to infestation mated for longer. If females control copula duration, given that short copulations often result in mating failure, female choice could act on parasite resistance.
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Affiliation(s)
- Bruno A Buzatto
- Centre for Evolutionary Biology, School of Biological Sciences (M092), The University of Western Australia, Crawley, WA, Australia
- Department of Biological Sciences (E8C 209), Macquarie University, Sydney, NSW, Australia
| | - Janne S Kotiaho
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
- School of Resource Wisdom, University of Jyväskylä, Jyväskylä, Finland
| | - Larissa A F Assis
- Departamento de Ecologia, Instituto de Biociências, Rua do Matão, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Leigh W Simmons
- Centre for Evolutionary Biology, School of Biological Sciences (M092), The University of Western Australia, Crawley, WA, Australia
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11
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Simmons LW, Fitzpatrick JL. Female genitalia can evolve more rapidly and divergently than male genitalia. Nat Commun 2019; 10:1312. [PMID: 30899023 PMCID: PMC6428859 DOI: 10.1038/s41467-019-09353-0] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 03/07/2019] [Indexed: 01/02/2023] Open
Abstract
Male genitalia exhibit patterns of divergent evolution driven by sexual selection. In contrast, for many taxonomic groups, female genitalia are relatively uniform and their patterns of evolution remain largely unexplored. Here we quantify variation in the shape of female genitalia across onthophagine dung beetles, and use new comparative methods to contrast their rates of divergence with those of male genitalia. As expected, male genital shape has diverged more rapidly than a naturally selected trait, the foretibia. Remarkably, female genital shape has diverged nearly three times as fast as male genital shape. Our results dispel the notion that female genitalia do not show the same patterns of divergent evolution as male genitalia, and suggest that female genitalia are under sexual selection through their role in female choice. Although male genital shape is known to evolve rapidly in response to sexual selection, relatively little is known about the evolution of female genital shape. Here, the authors show that across onthophagine dung beetles, female genital shape has diverged much more rapidly than male genital shape.
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Affiliation(s)
- Leigh W Simmons
- Centre for Evolutionary Biology, School of Biological Sciences (M092), The University of Western Australia, Crawley, WA, 6009, Australia.
| | - John L Fitzpatrick
- Department of Zoology/Ethology, Stockholm University, Svante Arrhenius väg 18B, SE-10691, Stockholm, Sweden
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12
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McCullough EL, Buzatto BA, Simmons LW. Population density mediates the interaction between pre‐ and postmating sexual selection. Evolution 2018; 72:893-905. [DOI: 10.1111/evo.13455] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 01/04/2018] [Accepted: 02/02/2018] [Indexed: 12/16/2022]
Affiliation(s)
- Erin L. McCullough
- Centre for Evolutionary Biology, School of Biological Sciences (M092) The University of Western Australia Crawley Western Australia 6009 Australia
| | - Bruno A. Buzatto
- Centre for Evolutionary Biology, School of Biological Sciences (M092) The University of Western Australia Crawley Western Australia 6009 Australia
| | - Leigh W. Simmons
- Centre for Evolutionary Biology, School of Biological Sciences (M092) The University of Western Australia Crawley Western Australia 6009 Australia
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13
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Parzer HF, David Polly P, Moczek AP. The evolution of relative trait size and shape: insights from the genitalia of dung beetles. Dev Genes Evol 2018; 228:83-93. [PMID: 29423654 DOI: 10.1007/s00427-018-0602-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 01/09/2018] [Indexed: 01/14/2023]
Abstract
Insects show relatively little genital variation within species compared to extraordinary and often rapid diversification among species. It has been suggested that selection for reproductive isolation through differences in genital shape might explain this phenomenon. This hypothesis predicts that populations diverge faster in genital shape than in genital size. We tested this prediction in males from 10 dung beetle species with known phylogenetic relationships from the genus Onthophagus (Coleoptera: Scarabaeidae), including four species for which we were able to sample multiple populations. Specifically, we compared intra- and interspecific differentiation in shape and relative sizes of genitalia and calculated their respective evolutionary rates. We compared these rates to two similarly sized non-genital traits, the head and the fore-tibia. We found significant intraspecific variation in genital shape in all four species for which multiple populations were sampled, but for three of them we also identified significant relative size variation. We also found that genital shape evolved at higher rates than relative genital size. Genital shape evolved faster than head shape, but not fore-tibia shape. However, shapes of all measured structures evolved faster than their relative size. We discuss the functional constraints that may bias the developmental evolution of relative size and shape of genitalia and other morphological traits.
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Affiliation(s)
- Harald F Parzer
- Department of Biology, Indiana University, Bloomington, IN, USA. .,Department of Biology and Allied Health Science, Fairleigh Dickinson University, Madison, NJ, USA.
| | - P David Polly
- Department of Biology, Indiana University, Bloomington, IN, USA.,Department of Earth and Atmospheric Sciences, Indiana University, Bloomington, IN, USA
| | - Armin P Moczek
- Department of Biology, Indiana University, Bloomington, IN, USA
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14
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Genevcius BC, Schwertner CF. Strong functional integration among multiple parts of the complex male and female genitalia of stink bugs. Biol J Linn Soc Lond 2017. [DOI: 10.1093/biolinnean/blx095] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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15
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Hernández L, Aisenberg A, Molina J. Mating plugs and sexual cannibalism in the Colombian orb-web spiderLeucauge mariana. Ethology 2017. [DOI: 10.1111/eth.12697] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Linda Hernández
- Centro de Investigaciones en Microbiología y Parasitología Tropical - CIMPAT; Bogotá Universidad de los Andes; Bogotá Colombia
| | - Anita Aisenberg
- Laboratorio de Etología, Ecología y Evolución; Instituto de Investigaciones Biológicas Clemente Estable; Montevideo Uruguay
| | - Jorge Molina
- Centro de Investigaciones en Microbiología y Parasitología Tropical - CIMPAT; Bogotá Universidad de los Andes; Bogotá Colombia
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16
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Richmond MP, Park J, Henry CS. The function and evolution of male and female genitalia in
Phyllophaga
Harris scarab beetles (Coleoptera: Scarabaeidae). J Evol Biol 2016; 29:2276-2288. [DOI: 10.1111/jeb.12955] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 06/23/2016] [Accepted: 07/13/2016] [Indexed: 12/01/2022]
Affiliation(s)
- M. P. Richmond
- Department of Ecology and Evolutionary Biology University of Connecticut Storrs CT USA
- Division of Biological Sciences UC San Diego La Jolla New York CA USA
| | - J. Park
- Division of Biological Sciences UC San Diego La Jolla New York CA USA
- Institute for Genomic Medicine Columbia University New York NY USA
| | - C. S. Henry
- Department of Ecology and Evolutionary Biology University of Connecticut Storrs CT USA
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17
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Esteve-Altava B. In search of morphological modules: a systematic review. Biol Rev Camb Philos Soc 2016; 92:1332-1347. [DOI: 10.1111/brv.12284] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2016] [Revised: 05/06/2016] [Accepted: 05/10/2016] [Indexed: 12/25/2022]
Affiliation(s)
- Borja Esteve-Altava
- Department of Comparative Biomedical Sciences; Royal Veterinary College; Hawkshead Lane, North Mymms Hatfield Hertfordshire AL9 7TA UK
- Department of Anatomy; College of Medicine, Howard University; 520 W Street, NW, Numa Adams Building Washington DC 20059 USA
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Macagno ALM, Moczek AP. Appendage-patterning genes regulate male and female copulatory structures in horned beetles. Evol Dev 2016; 17:248-53. [PMID: 26174101 DOI: 10.1111/ede.12129] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Explaining the extraordinarily rapid diversification of insect copulatory structures has been a longstanding objective in evolutionary biology. However, remarkably little is known about the developmental genetic underpinnings of their formation. Furthermore, recent work has questioned whether male genitalic structures in beetles are serially homologous to appendages, or even homologous to the genitalia of other orders. Using RNA interference, we demonstrate that several cardinal appendage-patterning genes regulate the formation of copulatory structures in Onthophagus beetles of both sexes. These results are in strong disagreement with previous findings in the model beetle species Tribolium castaneum, but congruent with earlier studies in true bugs and flies. Our results support the hypotheses that genitalic development is largely conserved across insect orders, and that genitalia constitute serial appendage homologues. Moreover, we identify two patterning genes with striking phenotypic effects in both sexes. In these cases, the affected structures are known to interact functionally during copulation, but are not homologous to each other. This suggests that shared developmental regulation of male and female copulatory structures may extend beyond components related by descent to those related by function.
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Affiliation(s)
- Anna L M Macagno
- Department of Biology, Indiana University, 915 East Third Street, 102 Myers Hall, Bloomington, Indiana, 47405-7107, USA
| | - Armin P Moczek
- Department of Biology, Indiana University, 915 East Third Street, 102 Myers Hall, Bloomington, Indiana, 47405-7107, USA
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19
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McCullough EL, Simmons LW. Selection on male physical performance during male–male competition and female choice. Behav Ecol 2016. [DOI: 10.1093/beheco/arw033] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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20
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Holwell GI, Kazakova O, Evans F, O’Hanlon JC, Barry KL. The Functional Significance of Chiral Genitalia: Patterns of Asymmetry, Functional Morphology and Mating Success in the Praying Mantis Ciulfina baldersoni. PLoS One 2015; 10:e0128755. [PMID: 26107629 PMCID: PMC4479579 DOI: 10.1371/journal.pone.0128755] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Accepted: 05/01/2015] [Indexed: 11/29/2022] Open
Abstract
Genital asymmetry is relatively common and widespread throughout the animal kingdom. The functional significance of genital asymmetry is however, poorly understood for most species. Male praying mantids of the genus Ciulfina are remarkable in possessing complex and directionally asymmetric genital phallomeres in some species, and chirally dimorphic/antisymmetric genitalia in others. Here we explore the chiral dimorphism in male genitalia of Ciulfina baldersoni which appear to exhibit genital antisymmetry. We test whether genital orientation influences mating success, copulation duration and the attachment duration of spermatophores. Additionally we investigate genital interactions between male and females using x-ray micro-computed tomography (micro-CT) and scanning electron microscopy (SEM). Lastly we assess whether genital asymmetry is associated with non-genital morphological asymmetry of a range of traits. Our results highlight the complex functional morphology of genitalia in this praying mantis species and yet demonstrate no functional difference between dextral and sinistral morphs other than the direction of attachment with both morphs enjoying equal levels of mating success. Chiral morphs also did not strongly associate with any other forms of asymmetry. We therefore conclude that genital chirality in Ciulfina baldersoni is a likely case of antisymmetry with no functional significance to genital orientation, and is likely to be selectively neutral.
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Affiliation(s)
- Gregory I. Holwell
- School of Biological Sciences, The University of Auckland, Auckland, 1142, New Zealand
- Department of Biological Sciences, Macquarie University, Sydney, NSW 2109, Australia
- * E-mail:
| | - Olga Kazakova
- Department of Biological Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Felicity Evans
- Department of Biological Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - James C. O’Hanlon
- Department of Biological Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Katherine L. Barry
- Department of Biological Sciences, Macquarie University, Sydney, NSW 2109, Australia
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Cayetano L, Bonduriansky R. Condition dependence of male and female genital structures in the seed beetle Callosobruchus maculatus (Coleoptera: Bruchidae). J Evol Biol 2015; 28:1364-72. [PMID: 26077617 DOI: 10.1111/jeb.12659] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 05/13/2015] [Indexed: 01/16/2023]
Abstract
Theory predicts that costly secondary sexual traits will evolve heightened condition dependence, and many studies have reported strong condition dependence of signal and weapon traits in a variety of species. However, although genital structures often play key roles in intersexual interactions and appear to be subject to sexual or sexually antagonistic selection, few studies have examined the condition dependence of genital structures, especially in both sexes simultaneously. We investigated the responses of male and female genital structures to manipulation of larval diet quality (new versus once-used mung beans) in the bruchid seed beetle Callosobruchus maculatus. We quantified effects on mean relative size and static allometry of the male aedeagus, aedeagal spines, flap and paramere and the female reproductive tract and bursal spines. None of the male traits showed a significant effect of diet quality. In females, we found that longer bursal spines (relative to body size) were expressed on low-quality diet. Although the function of bursal spines is poorly understood, we suggest that greater bursal spine length in low-condition females may represent a sexually antagonistic adaptation. Overall, we found no evidence that genital traits in C. maculatus are expressed to a greater extent when nutrients are more abundant. This suggests that, even though some genital traits appear to function as secondary sexual traits, genital traits do not exhibit heightened condition dependence in this species. We discuss possible reasons for this finding.
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Affiliation(s)
- L Cayetano
- EvoLab, Department of Environmental Science, Policy and Management, University of California, Berkeley, Berkeley, CA, USA
| | - R Bonduriansky
- Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, The University of New South Wales, Sydney, NSW, Australia
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23
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An unfinished speciation process revealed by geometric morphometrics, horn allometries and biomolecular analyses: The case of the fracticornis–similis–opacicollis species complex of the genus Onthophagus (Coleoptera: Scarabaeidae). ZOOL ANZ 2013. [DOI: 10.1016/j.jcz.2012.11.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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24
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House CM, Simmons LW. The genetics of primary and secondary sexual character trade-offs in a horned beetle. J Evol Biol 2012; 25:1711-7. [PMID: 22775558 DOI: 10.1111/j.1420-9101.2012.02559.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
When structures compete for shared resources, this may lead to acquisition and allocation trade-offs so that the enlargement of one structure occurs at the expense of another. Among the studies of morphological trade-offs, their importance has been demonstrated primarily through experimental manipulations and comparative analyses. Relatively, a few studies have investigated the underlying genetic basis of phenotypic patterns. Here, we use a half-sibling breeding design to determine the genetic underpinnings of the phenotypic trade-off between head horns and the male copulatory organ or aedeagus that has been found in the dung beetle Onthophagus taurus. Instead of the predicted negative genetic covariance among characters that trade-off, we find positive genetic covariance between absolute horn and aedeagus length and zero genetic covariance between relative horn and aedeagus length. Therefore, although the genetic covariance between absolute horn and aedeagus length would constrain the independent evolution of primary and secondary sexual characters in this population, there was no evidence of a trade-off. We discuss alternative hypotheses for the observed patterns of genetic correlation between traits that compete for resources and the implications that these have for selection and the evolution of such traits.
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Affiliation(s)
- C M House
- Centre for Ecology and Conservation, School of Biosciences, University of Exeter, Cornwall Campus, Penryn, UK
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25
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Okuzaki Y, Takami Y, Tsuchiya Y, Sota T. Mating Behavior and the Function of the Male Genital Spine in the Ground BeetleCarabus clathratus. Zoolog Sci 2012; 29:428-32. [DOI: 10.2108/zsj.29.428] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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26
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Pizzo A, Macagno ALM, Dusini S, Palestrini C. Trade-off between horns and other functional traits in two Onthophagus species (Scarabaeidae, Coleoptera). ZOOMORPHOLOGY 2012. [DOI: 10.1007/s00435-012-0148-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Wojcieszek JM, Austin P, Harvey MS, Simmons LW. Micro-CT scanning provides insight into the functional morphology of millipede genitalia. J Zool (1987) 2012. [DOI: 10.1111/j.1469-7998.2011.00892.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- J. M. Wojcieszek
- Centre for Evolutionary Biology; School of Animal Biology M092; University of Western Australia; Crawley; WA; Australia
| | - P. Austin
- CSIRO Process Science and Engineering; Australian Minerals Research Centre; Karawara; WA; Australia
| | | | - L. W. Simmons
- Centre for Evolutionary Biology; School of Animal Biology M092; University of Western Australia; Crawley; WA; Australia
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Shape--but not size--codivergence between male and female copulatory structures in Onthophagus beetles. PLoS One 2011; 6:e28893. [PMID: 22194942 PMCID: PMC3237555 DOI: 10.1371/journal.pone.0028893] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Accepted: 11/16/2011] [Indexed: 02/08/2023] Open
Abstract
Genitalia are among the fastest evolving morphological traits in arthropods. Among the many hypotheses aimed at explaining this observation, some explicitly or implicitly predict concomitant male and female changes of genital traits that interact during copulation (i.e., lock and key, sexual conflict, cryptic female choice and pleiotropy). Testing these hypotheses requires insights into whether male and female copulatory structures that physically interact during mating also affect each other's evolution and patterns of diversification. Here we compare and contrast size and shape evolution of male and female structures that are known to interact tightly during copulation using two model systems: (a) the sister species O. taurus (1 native, 3 recently established populations) and O. illyricus, and (b) the species-complex O. fracticornis-similis-opacicollis. Partial Least Squares analyses indicated very little to no correlation between size and shape of copulatory structures, both in males and females. Accordingly, comparing shape and size diversification patterns of genitalia within each sex showed that the two components diversify readily - though largely independently of each other - within and between species. Similarly, comparing patterns of divergence across sexes showed that relative sizes of male and female copulatory organs diversify largely independent of each other. However, performing this analysis for genital shape revealed a signature of parallel divergence. Our results therefore suggest that male and female copulatory structures that are linked mechanically during copulation may diverge in concert with respect to their shapes. Furthermore, our results suggest that genital divergence in general, and co-divergence of male and female genital shape in particular, can evolve over an extraordinarily short time frame. Results are discussed in the framework of the hypotheses that assume or predict concomitant evolutionary changes in male and female copulatory organs.
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Simmons LW, Garcia-Gonzalez F. Experimental coevolution of male and female genital morphology. Nat Commun 2011; 2:374. [DOI: 10.1038/ncomms1379] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2011] [Accepted: 06/08/2011] [Indexed: 11/09/2022] Open
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MACAGNO ANNALM, PIZZO ASTRID, ROLANDO ANTONIO, PALESTRINI CLAUDIA. Size and shape interspecific divergence patterns partly reflect phylogeny in an Onthophagus species-complex (Coleoptera: Scarabaeidae). Zool J Linn Soc 2011. [DOI: 10.1111/j.1096-3642.2010.00684.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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31
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Tarasov SI, Solodovnikov AY. Phylogenetic analyses reveal reliable morphological markers to classify mega-diversity in Onthophagini dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae). Cladistics 2011; 27:490-528. [DOI: 10.1111/j.1096-0031.2011.00351.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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32
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van Lieshout E, Elgar MA. Longer exaggerated male genitalia confer defensive sperm-competitive benefits in an earwig. Evol Ecol 2010. [DOI: 10.1007/s10682-010-9422-1] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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KAMIMURA YOSHITAKA, IWASE RYOTA. Evolutionary genetics of genital size and lateral asymmetry in the earwig Euborellia plebeja (Dermaptera: Anisolabididae). Biol J Linn Soc Lond 2010. [DOI: 10.1111/j.1095-8312.2010.01491.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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34
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van Lieshout E. Male genital length and mating status differentially affect mating behaviour in an earwig. Behav Ecol Sociobiol 2010. [DOI: 10.1007/s00265-010-1021-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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35
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Evolution of genitalia: theories, evidence, and new directions. Genetica 2010; 138:5-18. [PMID: 19308664 DOI: 10.1007/s10709-009-9358-y] [Citation(s) in RCA: 169] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2008] [Accepted: 02/26/2009] [Indexed: 10/21/2022]
Abstract
Many hypotheses have been proposed to explain why male intromittent genitalia consistently tend to diverge more rapidly than other body traits of the same individuals in a wide range of animal taxa. Currently the two most popular involve sexual selection: sexually antagonistic coevolution (SAC) and cryptic female choice (CFC). A review of the most extensive attempts to discriminate between these two hypotheses indicates that SAC is not likely to have played a major role in explaining this pattern of genital evolution. Promising lines for future, more direct tests of CFC include experimental modification of male genital form and female sensory abilities, analysis of possible male-female dialogues during copulation, and direct observations of genital behavior.
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36
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Evolutionary Response to Sexual Selection in Male Genital Morphology. Curr Biol 2009; 19:1442-6. [DOI: 10.1016/j.cub.2009.06.056] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2009] [Revised: 06/23/2009] [Accepted: 06/23/2009] [Indexed: 11/20/2022]
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37
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Cordero C. On the function of cornuti, sclerotized structures of the endophallus of Lepidoptera. Genetica 2009; 138:27-35. [DOI: 10.1007/s10709-009-9363-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2009] [Accepted: 04/06/2009] [Indexed: 11/30/2022]
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38
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EBERHARD W, RODRIGUEZ RL, POLIHRONAKIS M. Pitfalls in understanding the functional significance of genital allometry. J Evol Biol 2009; 22:435-45. [DOI: 10.1111/j.1420-9101.2008.01654.x] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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40
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Evans JP, Simmons LW. The genetic basis of traits regulating sperm competition and polyandry: can selection favour the evolution of good- and sexy-sperm? Genetica 2007; 134:5-19. [PMID: 17619174 DOI: 10.1007/s10709-007-9162-5] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2007] [Accepted: 06/05/2007] [Indexed: 11/28/2022]
Abstract
The good-sperm and sexy-sperm (GS-SS) hypotheses predict that female multiple mating (polyandry) can fuel sexual selection for heritable male traits that promote success in sperm competition. A major prediction generated by these models, therefore, is that polyandry will benefit females indirectly via their sons' enhanced fertilization success. Furthermore, like classic 'good genes' and 'sexy son' models for the evolution of female preferences, GS-SS processes predict a genetic correlation between genes for female mating frequency (analogous to the female preference) and those for traits influencing fertilization success (the sexually selected traits). We examine the premise for these predictions by exploring the genetic basis of traits thought to influence fertilization success and female mating frequency. We also highlight recent debates that stress the possible genetic constraints to evolution of traits influencing fertilization success via GS-SS processes, including sex-linked inheritance, nonadditive effects, interacting parental genotypes, and trade-offs between integrated ejaculate components. Despite these possible constraints, the available data suggest that male traits involved in sperm competition typically exhibit substantial additive genetic variance and rapid evolutionary responses to selection. Nevertheless, the limited data on the genetic variation in female mating frequency implicate strong genetic maternal effects, including X-linkage, which is inconsistent with GS-SS processes. Although the relative paucity of studies on the genetic basis of polyandry does not allow us to draw firm conclusions about the evolutionary origins of this trait, the emerging pattern of sex linkage in genes for polyandry is more consistent with an evolutionary history of antagonistic selection over mating frequency. We advocate further development of GS-SS theory to take account of the complex evolutionary dynamics imposed by sexual conflict over mating frequency.
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Affiliation(s)
- Jonathan P Evans
- Centre for Evolutionary Biology, School of Animal Biology M092, The University of Western Australia, Nedlands, WA, Australia.
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