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Kappeler PM, Benhaiem S, Fichtel C, Fromhage L, Höner OP, Jennions MD, Kaiser S, Krüger O, Schneider JM, Tuni C, van Schaik J, Goymann W. Sex roles and sex ratios in animals. Biol Rev Camb Philos Soc 2023; 98:462-480. [PMID: 36307924 DOI: 10.1111/brv.12915] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 10/12/2022] [Accepted: 10/14/2022] [Indexed: 11/29/2022]
Abstract
In species with separate sexes, females and males often differ in their morphology, physiology and behaviour. Such sex-specific traits are functionally linked to variation in reproductive competition, mate choice and parental care, which have all been linked to sex roles. At the 150th anniversary of Darwin's theory on sexual selection, the question of why patterns of sex roles vary within and across species remains a key topic in behavioural and evolutionary ecology. New theoretical, experimental and comparative evidence suggests that variation in the adult sex ratio (ASR) is a key driver of variation in sex roles. Here, we first define and discuss the historical emergence of the sex role concept, including recent criticisms and rebuttals. Second, we review the various sex ratios with a focus on ASR, and explore its theoretical links to sex roles. Third, we explore the causes, and especially the consequences, of biased ASRs, focusing on the results of correlational and experimental studies of the effect of ASR variation on mate choice, sexual conflict, parental care and mating systems, social behaviour, hormone physiology and fitness. We present evidence that animals in diverse societies are sensitive to variation in local ASR, even on short timescales, and propose explanations for conflicting results. We conclude with an overview of open questions in this field integrating demography, life history and behaviour.
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Affiliation(s)
- Peter M Kappeler
- Behavioral Ecology and Sociobiology Unit, German Primate Center - Leibniz Institute of Primatology, Kellnerweg 4, 37077, Göttingen, Germany
- Department of Sociobiology/Anthropology, University of Göttingen, Kellnerweg 6, 37077, Göttingen, Germany
| | - Sarah Benhaiem
- Department of Ecological Dynamics, Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, D-10315, Berlin, Germany
| | - Claudia Fichtel
- Behavioral Ecology and Sociobiology Unit, German Primate Center - Leibniz Institute of Primatology, Kellnerweg 4, 37077, Göttingen, Germany
| | - Lutz Fromhage
- Department of Biological and Environmental Science, Ambiotica, University of Jyväskylä, PO Box 35, 40014, Jyväskylä, Finland
| | - Oliver P Höner
- Department of Evolutionary Ecology, Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, D-10315, Berlin, Germany
| | - Michael D Jennions
- Division of Ecology & Evolution, Research School of Biology, ANU College of Science, The Australian National University, RN Robertson Building, 46 Sullivans Creek Road, Canberra, ACT, 2600, Australia
| | - Sylvia Kaiser
- Department of Behavioural Biology, University of Münster, Badestr. 13, 48149, Münster, Germany
| | - Oliver Krüger
- Department of Animal Behavior, Bielefeld University, Morgenbreede 45, 33615, Bielefeld, Germany
| | - Jutta M Schneider
- Department of Biology, Institute of Zoology, Universität Hamburg, Martin-Luther-King Platz 3, 20146, Hamburg, Germany
| | - Cristina Tuni
- Department of Biology II, Ludwig Maximilians University of Munich, Großhaderner Str 2, 82152, Planegg-Martinsried, Germany
| | - Jaap van Schaik
- Applied Zoology and Nature Conservation, University of Greifswald, Loitzer Str. 26, 17489, Greifswald, Germany
| | - Wolfgang Goymann
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, Eberhard-Gwinner-Str. 6a, D-82319, Seewiesen, Germany
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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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3
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A decade of sexual selection studies reveals patterns and processes of fitness variation in male collared lizards. Anim Behav 2021. [DOI: 10.1016/j.anbehav.2021.07.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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4
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Walter KV, Conroy-Beam D, Buss DM, Asao K, Sorokowska A, Sorokowski P, Aavik T, Akello G, Alhabahba MM, Alm C, Amjad N, Anjum A, Atama CS, Duyar DA, Ayebare R, Batres C, Bendixen M, Bensafia A, Bizumic B, Boussena M, Butovskaya M, Can S, Cantarero K, Carrier A, Cetinkaya H, Croy I, Cueto RM, Czub M, Dronova D, Dural S, Duyar I, Ertugrul B, Espinosa A, Estevan I, Esteves CS, Fang L, Frackowiak T, Garduño JC, González KU, Guemaz F, Gyuris P, Halamová M, Herak I, Horvat M, Hromatko I, Hui CM, Jaafar JL, Jiang F, Kafetsios K, Kavčič T, Kennair LEO, Kervyn N, Khanh Ha TT, Khilji IA, Köbis NC, Lan HM, Láng A, Lennard GR, León E, Lindholm T, Linh TT, Lopez G, Luot NV, Mailhos A, Manesi Z, Martinez R, McKerchar SL, Meskó N, Misra G, Monaghan C, Mora EC, Moya-Garófano A, Musil B, Natividade JC, Niemczyk A, Nizharadze G, Oberzaucher E, Oleszkiewicz A, Omar-Fauzee MS, Onyishi IE, Özener B, Pagani AF, Pakalniskiene V, Parise M, Pazhoohi F, Pisanski A, Pisanski K, Ponciano E, Popa C, Prokop P, Rizwan M, Sainz M, Salkičević S, Sargautyte R, Sarmány-Schuller I, Schmehl S, Sharad S, Siddiqui RS, Simonetti F, Stoyanova SY, Tadinac M, Correa Varella MA, Vauclair CM, Vega LD, Widarini DA, Yoo G, Zaťková MM, Zupančič M. Sex differences in human mate preferences vary across sex ratios. Proc Biol Sci 2021; 288:20211115. [PMID: 34284630 PMCID: PMC8292757 DOI: 10.1098/rspb.2021.1115] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 06/28/2021] [Indexed: 11/12/2022] Open
Abstract
A wide range of literature connects sex ratio and mating behaviours in non-human animals. However, research examining sex ratio and human mating is limited in scope. Prior work has examined the relationship between sex ratio and desire for short-term, uncommitted mating as well as outcomes such as marriage and divorce rates. Less empirical attention has been directed towards the relationship between sex ratio and mate preferences, despite the importance of mate preferences in the human mating literature. To address this gap, we examined sex ratio's relationship to the variation in preferences for attractiveness, resources, kindness, intelligence and health in a long-term mate across 45 countries (n = 14 487). We predicted that mate preferences would vary according to relative power of choice on the mating market, with increased power derived from having relatively few competitors and numerous potential mates. We found that each sex tended to report more demanding preferences for attractiveness and resources where the opposite sex was abundant, compared to where the opposite sex was scarce. This pattern dovetails with those found for mating strategies in humans and mate preferences across species, highlighting the importance of sex ratio for understanding variation in human mate preferences.
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Affiliation(s)
- Kathryn V. Walter
- Department of Psychological and Brain Sciences, University of California, Santa Barbara, CA 93106, USA
| | - Daniel Conroy-Beam
- Department of Psychological and Brain Sciences, University of California, Santa Barbara, CA 93106, USA
| | - David M. Buss
- Department of Psychology, University of Texas at Austin, Austin, TX 78712, USA
| | - Kelly Asao
- Department of Psychology, Westminster College, Salt Lake City, UT 84105, USA
| | - Agnieszka Sorokowska
- Institute of Psychology, University of Wroclaw, Wroclaw 50137, Poland
- Smell and Taste Clinic, Department of Otorhinolaryngology, TU Dresden, Dresden 01307, Germany
| | - Piotr Sorokowski
- Institute of Psychology, University of Wroclaw, Wroclaw 50137, Poland
| | - Toivo Aavik
- Institute of Psychology, University of Tartu, Tartu 50090, Estonia
| | - Grace Akello
- Department of Mental Health, Faculty of Medicine, Gulu University, Gulu 166, Uganda
| | | | - Charlotte Alm
- Department of Psychology, Stockholm University, Stockholm 10691, Sweden
| | - Naumana Amjad
- Department of Applied Psychology, NUR International University, Lahore, Pakistan
| | - Afifa Anjum
- Institute of Applied Psychology, University of the Punjab, Lahore 54590, Pakistan
| | | | | | | | - Carlota Batres
- Department of Psychology, Franklin and Marshall College, Lancaster 17603, USA
| | - Mons Bendixen
- Department of Psychology, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway
| | - Aicha Bensafia
- Laboratory Education-Formation-Travail (EFORT), Department of Sociology, and
| | - Boris Bizumic
- Research School of Psychology, Australian National University, Canberra 2601, Australia
| | - Mahmoud Boussena
- Laboratory EFORT, Department of Psychology and Educational Sciences, University of Algiers 2, Algiers 16000, Algeria
| | - Marina Butovskaya
- Institute of Ethnology and Anthropology, Russian Academy of Sciences, Moscow 119991, Russia
- Center for Social Anthropology, Russian State University for the Humanities, Moscow 119991, Russia
| | - Seda Can
- Department of Psychology, Izmir University of Economics, Izmir 35300, Turkey
| | - Katarzyna Cantarero
- Social Behavior Research Center, Faculty in Wroclaw, SWPS University of Social Sciences and Humanities, Wroclaw 53238, Poland
| | - Antonin Carrier
- Psychology Faculty (Center for the Study of Social Behavior), and
| | - Hakan Cetinkaya
- Department of Psychology, Ankara University, Ankara 6560, Turkey
| | - Ilona Croy
- Department of Psychotherapy and Psychosomatic Medicine, TU Dresden, Dresden 1069, Germany
| | - Rosa María Cueto
- Grupo de Psicología Política y Social (GPPS), Departamento de Psicología, Pontificia Universidad Católica del Perú, Lima 15088, Perú
| | - Marcin Czub
- Department of Psychology, Westminster College, Salt Lake City, UT 84105, USA
| | - Daria Dronova
- Institute of Ethnology and Anthropology, Russian Academy of Sciences, Moscow 119991, Russia
| | - Seda Dural
- Department of Psychology, Izmir University of Economics, Izmir 35300, Turkey
| | - Izzet Duyar
- Deparment of Anthropology, Istanbul University, Istanbul 34452, Turkey
| | - Berna Ertugrul
- Deparment of Anthropology, Istanbul University, Istanbul 34452, Turkey
| | - Agustín Espinosa
- Grupo de Psicología Política y Social (GPPS), Departamento de Psicología, Pontificia Universidad Católica del Perú, Lima 15088, Perú
| | - Ignacio Estevan
- Facultad de Psicología, Universidad de la República, Motevideo 11200, Uruguay
| | - Carla Sofia Esteves
- Universidade Católica Portuguesa, Católica Lisbon School of Business and Economics, Católica Lisbon Research Unit in Business and Economics, Portugal
| | - Luxi Fang
- Department of Psychology, Chinese University of Hong Kong, Hong Kong, People's Republic of China
| | - Tomasz Frackowiak
- Institute of Psychology, University of Wroclaw, Wroclaw 50137, Poland
| | | | | | - Farida Guemaz
- Department of Psychology and Educational Sciences, University of Sétif2, Sétif 16000, Algeria
| | - Petra Gyuris
- Institute of Psychology, University of Pécs, Pécs 7624, Hungary
| | - Mária Halamová
- Faculty of Social Sciences and Health Care, Department of Psychological Sciences, Constantine the Philosopher University in Nitra, Nitra 94974, Slovakia
| | - Iskra Herak
- Louvain Research Institute in Management and Organisations (LOURiM), Université Catholique de Louvain, Louvain-la-Neuve 1348, Belgium
| | - Marina Horvat
- Faculty of Arts, Department of Psychology, University of Maribor, Maribor 2000, Slovenia
| | - Ivana Hromatko
- Department of Psychology, Faculty for Humanities and Social Sciences, University of Zagreb, Zagreb 10000, Croatia
| | - Chin-Ming Hui
- Escuela Nacional de Estudios Superiores, Unidad Morelia UNAM, Morelia 58190, Mexico
| | - Jas Laile Jaafar
- Department of Educational Psychology and Counseling, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Feng Jiang
- Organization and Human Resource Management, Central University of Finance and Economics, Beijing 102202, People's Republic of China
| | - Konstantinos Kafetsios
- School of Fine Arts, Aristotle University of Thessaloniki, Greece and Katedra Psychologie, Palacký University Olomouc, Czech Republic
| | | | | | - Nicolas Kervyn
- Louvain Research Institute in Management and Organisations (LOURiM), Université Catholique de Louvain, Louvain-la-Neuve 1348, Belgium
| | - Truong Thi Khanh Ha
- Department of Psychology, University of Social Sciences and Humanities, Vietnam National University, Hanoi 100000, Vietnam
| | - Imran Ahmed Khilji
- Department of Psychology, Islamabad Model College for Boys, F-10/4, Islamabad 44000, Pakistan
| | - Nils C. Köbis
- Center for Research in Experimental Economics and Political Decision Making, Department of Economics, University of Amsterdam, Amsterdam 1081, The Netherlands
| | - Hoang Moc Lan
- Department of Psychology, University of Social Sciences and Humanities, Vietnam National University, Hanoi 100000, Vietnam
| | - András Láng
- Institute of Psychology, University of Pécs, Pécs 7624, Hungary
| | - Georgina R. Lennard
- Research School of Psychology, Australian National University, Canberra 2601, Australia
| | - Ernesto León
- Grupo de Psicología Política y Social (GPPS), Departamento de Psicología, Pontificia Universidad Católica del Perú, Lima 15088, Perú
| | - Torun Lindholm
- Department of Psychology, Stockholm University, Stockholm 10691, Sweden
| | - Trinh Thi Linh
- Department of Psychology, University of Social Sciences and Humanities, Vietnam National University, Hanoi 100000, Vietnam
| | - Giulia Lopez
- Department of Psychology, Università Cattolica del Sacro Cuore, Milan 20123, Italy
| | - Nguyen Van Luot
- Department of Psychology, University of Social Sciences and Humanities, Vietnam National University, Hanoi 100000, Vietnam
| | - Alvaro Mailhos
- Facultad de Psicología, Universidad de la República, Motevideo 11200, Uruguay
| | - Zoi Manesi
- Department of Experimental and Applied Psychology, Vrije Universiteit Amsterdam, Amsterdam 1081, The Netherlands
| | - Rocio Martinez
- Department of Social Psychology, University of Granada, Grenada 18010, Spain
| | - Sarah L. McKerchar
- Research School of Psychology, Australian National University, Canberra 2601, Australia
| | - Norbert Meskó
- Institute of Psychology, University of Pécs, Pécs 7624, Hungary
| | - Girishwar Misra
- Department of Psychology, University of Delhi, Delhi 110021, India
| | - Conal Monaghan
- Research School of Psychology, Australian National University, Canberra 2601, Australia
| | - Emanuel C. Mora
- Department of Animal and Human Biology, Faculty of Biology, University of Havana, Havana, Cuba
| | - Alba Moya-Garófano
- Department of Psychology, Islamabad Model College for Boys, F-10/4, Islamabad 44000, Pakistan
| | - Bojan Musil
- Faculty of Arts, Department of Psychology, University of Maribor, Maribor 2000, Slovenia
| | - Jean Carlos Natividade
- Department of Psychology, Pontifical Catholic University of Rio de Janeiro, Rio de Janeiro 22451-000, Brazil
| | | | - George Nizharadze
- Department of Social Sciences, Free University of Tbilisi, Tbilisi 2, Georgia
| | | | - Anna Oleszkiewicz
- Institute of Psychology, University of Wroclaw, Wroclaw 50137, Poland
- Smell and Taste Clinic, Department of Otorhinolaryngology, TU Dresden, Dresden 01307, Germany
| | | | - Ike E. Onyishi
- Department of Psychology, University of Nigeria, Nsukka 410002, Nigeria
| | - Baris Özener
- Deparment of Anthropology, Istanbul University, Istanbul 34452, Turkey
| | | | | | - Miriam Parise
- Department of Psychology, Università Cattolica del Sacro Cuore, Milan 20123, Italy
| | - Farid Pazhoohi
- Department of Psychology, University of British Columbia, Vancouver, Canada V6T 1Z4
| | - Annette Pisanski
- Department of Animal and Human Biology, Faculty of Biology, University of Havana, Havana, Cuba
| | - Katarzyna Pisanski
- Institute of Psychology, University of Wroclaw, Wroclaw 50137, Poland
- Equipe de Neuro-Ethologie Sensorielle (ENES), Centre de Recherche en Neurosciences de Lyon (CRNL), Centre National de la Recherche Scientifique (CNRS), Jean Monnet University, Saint-Etienne, France
- CNRS National Center for Scientific Research, Dynamic Language Laboratory, University Lyon 2, Lyon, France
| | - Edna Ponciano
- Institute of Psychology, University of the State of Rio de Janeiro, Rio de Janeiro 21941-901, Brazil
- Center of Social Studies, University of Coimbra, 3004 Coimba, Portugal
| | - Camelia Popa
- Department of Psychology—Institute of Philosophy and Psychology “C. Rădulescu Motru” of Romanian Academy, UNATC Bucharest, Bucharest, Romania
| | - Pavol Prokop
- Department of Environmental Ecology and Landscape Management, Faculty of Natural Sciences, Comenius University, Bratislava 84215, Slovakia
- Institute of Zoology, Slovak Academy of Sciences, Bratislava 84506, Slovakia
| | - Muhammad Rizwan
- Department of Psychology, University of Haripur, 22620, Pakistan
| | - Mario Sainz
- Escuela de Psicología, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
| | - Svjetlana Salkičević
- Department of Psychology, Faculty for Humanities and Social Sciences, University of Zagreb, Zagreb 10000, Croatia
| | - Ruta Sargautyte
- Institute of Psychology, Vilnius University, Vilnius 1513, Lithuania
| | - Ivan Sarmány-Schuller
- Center for Social and Psychological Sciences, Institute of Experimental Psychology SAS, Bratislava, 84104, Slovakia
| | - Susanne Schmehl
- Faculty of Life Sciences, University of Vienna, Vienna 1090, Austria
| | - Shivantika Sharad
- Department of Applied Psychology, Vivekananda College, University of Delhi, Delhi 110095, India
| | - Razi Sultan Siddiqui
- Department of Management Sciences, DHA Suffa University, Karachi 75500, Pakistan
| | - Franco Simonetti
- School of Psychology, Pontificia Universidad Catolica de Chile, Santiago 8331150, Chile
| | | | - Meri Tadinac
- Department of Psychology, Faculty for Humanities and Social Sciences, University of Zagreb, Zagreb 10000, Croatia
| | - Marco Antonio Correa Varella
- Department of Experimental Psychology, Institute of Psychology, University of São Paulo, São Paulo 05508-030, Brazil
| | | | - Luis Diego Vega
- Department of Psychology and Educational Sciences, University of Sétif2, Sétif 16000, Algeria
| | - Dwi Ajeng Widarini
- Fakultas Ilmu Komunikasi, Universitas Prof. Dr Moestopo (Beragama), Jakarta 10270, Indonesia
| | - Gyesook Yoo
- Department of Child and Family Studies, Kyung Hee University, Seoul 024-47, Republic of Korea
| | - Marta Marta Zaťková
- Department of Psychology and Educational Sciences, University of Sétif2, Sétif 16000, Algeria
| | - Maja Zupančič
- Department of Psychology, Faculty of Arts, University of Ljubljana, Ljubljana 1000, Slovenia
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5
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López Galán A, Chung WS, Marshall NJ. Dynamic Courtship Signals and Mate Preferences in Sepia plangon. Front Physiol 2020; 11:845. [PMID: 32903768 PMCID: PMC7438932 DOI: 10.3389/fphys.2020.00845] [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: 12/21/2019] [Accepted: 06/24/2020] [Indexed: 11/17/2022] Open
Abstract
Communication in cuttlefish includes rapid changes in skin coloration and texture, body posture and movements, and potentially polarized signals. The dynamic displays are fundamental for mate choice and agonistic behavior. We analyzed the reproductive behavior of the mourning cuttlefish Sepia plangon in the laboratory. Mate preference was analyzed via choice assays (n = 33) under three sex ratios, 1 male (M): 1 female (F), 2M:1F, and 1M:2F. We evaluated the effect of modifying polarized light from the arms stripes and ambient light with polarized and unpolarized barriers between the cuttlefish. Additionally, to assess whether a particular trait was a determinant for mating, we used 3D printed cuttlefish dummies. The dummies had different sets of visual signals: two sizes (60 or 90 mm mantle length), raised or dropped arms, high or low contrast body coloration, and polarized or unpolarized filters to simulate the arms stripes. Frequency and duration (s) of courtship displays, mating, and agonistic behaviors were analyzed with GLM and ANOVAs. The behaviors, body patterns, and their components were integrated into an ethogram to describe the reproductive behavior of S. plangon. We identified 18 body patterns, 57 body patterns components, and three reproductive behaviors (mating, courtship, and mate guarding). Only sex ratio had a significant effect on courtship frequency, and the male courtship success rate was 80%. Five small (ML < 80 mm) males showed the dual-lateral display to access mates while avoiding fights with large males; this behavior is characteristic of male "sneaker" cuttlefish. Winner males showed up to 17 body patterns and 33 components, whereas loser males only showed 12 patterns and 24 components. We identified 32 combinations of body patterns and components that tended to occur in a specific order and were relevant for mating success in males. Cuttlefish were visually aware of the 3D-printed dummies; however, they did not start mating or agonistic behavior toward the dummies. Our findings suggest that in S. plangon, the dynamic courtship displays with specific sequences of visual signals, and the sex ratio are critical for mate choice and mating success.
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Affiliation(s)
- Alejandra López Galán
- Sensory Neurobiology Group, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia
| | - Wen-Sung Chung
- Sensory Neurobiology Group, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia
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6
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Female Self-Sexualization Covaries with Mate Value but Not Mate Availability. ADAPTIVE HUMAN BEHAVIOR AND PHYSIOLOGY 2020. [DOI: 10.1007/s40750-020-00133-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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7
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Integrating an individual-based model with approximate Bayesian computation to predict the invasion of a freshwater fish provides insights into dispersal and range expansion dynamics. Biol Invasions 2020. [DOI: 10.1007/s10530-020-02197-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
AbstractShort-distance dispersal enables introduced alien species to colonise and invade local habitats following their initial introduction, but is often poorly understood for many freshwater taxa. Knowledge gaps in range expansion of alien species can be overcome using predictive approaches such as individual based models (IBMs), especially if predictions can be improved through fitting to empirical data, but this can be challenging for models having multiple parameters. We therefore estimated the parameters of a model implemented in the RangeShifter IBM platform by approximate Bayesian computation (ABC) in order to predict the further invasion of a lowland river (Great Ouse, England) by a small-bodied invasive fish (bitterling Rhodeus sericeus). Prior estimates for parameters were obtained from the literature and expert opinion. Model fitting was conducted using a time-series (1983 to 2018) of sampling data at fixed locations and revealed that for 5 of 11 model parameters, the posterior distributions differed markedly from prior assumptions. In particular, sub-adult maximum emigration probability was substantially higher in the posteriors than priors. Simulations of bitterling range expansion predicted that following detection in 1984, their early expansion involved a relatively high population growth rate that stabilised after 5 years. The pattern of bitterling patch occupancy was sigmoidal, with 20% of the catchment occupied after 20 years, increasing to 80% after 30 years. Predictions were then for 95% occupancy after 69 years. The development of this IBM thus successfully simulated the range expansion dynamics of this small-bodied invasive fish, with ABC improving the simulation precision. This combined methodology also highlighted that sub-adult dispersal was more likely to contribute to the rapid colonisation rate than expert opinion suggested. These results emphasise the importance of time-series data for refining IBM parameters generally and increasing our understanding of dispersal behaviour and range expansion dynamics specifically.
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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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9
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Hata H, Uemura Y, Ouchi K, Matsuba H. Hybridization between an endangered freshwater fish and an introduced congeneric species and consequent genetic introgression. PLoS One 2019; 14:e0212452. [PMID: 30763376 PMCID: PMC6375628 DOI: 10.1371/journal.pone.0212452] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 02/01/2019] [Indexed: 11/19/2022] Open
Abstract
Artificial transplantation of organisms and consequent invasive hybridization can lead to the extinction of native species. In Matsuyama, Japan, a native bitterling fish, Tanakia lanceolata, is known to form hybrids with another bitterling species, T. limbata, which was recently introduced from western Kyushu, Japan. These bitterlings spawn in the gills of two freshwater unionid species, Pronodularia japanensis and Nodularia douglasiae nipponensis, which have rapidly declined on the Matsuyama Plain in the past 30 years. To gauge the effect of invasive hybridization, we determined the genetic introgression between T. lanceolata and T. limbata and analyzed the morphology of these species and their hybrids to infer their niche overlap. We collected adult individuals of Tanakia spp. and genotyped them based on six microsatellite loci and mitochondrial cytochrome b sequences. We analyzed their meristic characters and body shapes by geometric morphometrics. We found that 10.9% of all individuals collected were hybrids. Whereas T. lanceolata were more densely distributed downstream and T. limbata were distributed upstream, their hybrids were widely distributed, covering the entire range of native T. lanceolata. The body height and anal fin length of T. limbata were greater than those of T. lanceolata, but their hybrids were highly morphologically variable, covering both parental morphs, and were widely distributed in the habitats of both parental species. Hybridization has occurred in both directions, but introduced T. limbata females and native T. lanceolata males are more likely to have crossed. This study shows that invasive hybridization with the introduced T. limbata is a potential threat to the native population of T. lanceolata via genetic introgression and replacement of its niche in streams.
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Affiliation(s)
- Hiroki Hata
- Graduate School of Science and Engineering, Ehime University, Matsuyama, Ehime, Japan
- * E-mail:
| | - Yohsuke Uemura
- Department of Biology, Faculty of Science, Ehime University, Matsuyama, Ehime, Japan
| | - Kaito Ouchi
- Graduate School of Science and Engineering, Ehime University, Matsuyama, Ehime, Japan
| | - Hideki Matsuba
- Graduate School of Science and Engineering, Ehime University, Matsuyama, Ehime, Japan
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10
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Shuster SM, Willen RM, Keane B, Solomon NG. Alternative Mating Tactics in Socially Monogamous Prairie Voles, Microtus ochrogaster. Front Ecol Evol 2019. [DOI: 10.3389/fevo.2019.00007] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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11
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Mair MM, Ruther J. Territoriality and behavioural strategies at the natal host patch differ in two microsympatric Nasonia species. Anim Behav 2018. [DOI: 10.1016/j.anbehav.2018.07.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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12
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Braun CA, Baird TA, York JR. Behavioural plasticity in physically variable microhabitats: a field test of potential adaptive consequences in male collared lizards (Crotaphytus collaris). Biol J Linn Soc Lond 2018. [DOI: 10.1093/biolinnean/bly100] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Cody A Braun
- Department of Biology, University of Central Oklahoma, Edmond, OK, USA
| | - Troy A Baird
- Department of Biology, University of Central Oklahoma, Edmond, OK, USA
| | - Joshua R York
- Department of Biology, University of Oklahoma, Norman, OK, USA
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13
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Morgado-Santos M, Magalhães MF, Vicente L, Collares-Pereira MJ. Mate choice driven by genome in an allopolyploid fish complex. Behav Ecol 2018. [DOI: 10.1093/beheco/ary117] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- M Morgado-Santos
- Centro de Ecologia, Evolução e Alterações Climáticas (cE3c), Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal
| | - M F Magalhães
- Centro de Ecologia, Evolução e Alterações Climáticas (cE3c), Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal
| | - L Vicente
- Centro de Filosofia das Ciências da Universidade de Lisboa (CFCUL), Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal
| | - M J Collares-Pereira
- Centro de Ecologia, Evolução e Alterações Climáticas (cE3c), Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal
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14
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Affiliation(s)
- P. Muralidhar
- Department of Organismic and Evolutionary Biology Harvard University Cambridge MA USA
| | - M. A. Johnson
- Department of Biology Trinity University San Antonio TX USA
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15
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Karkarey R, Zambre A, Isvaran K, Arthur R. Alternative reproductive tactics and inverse size-assortment in a high-density fish spawning aggregation. BMC Ecol 2017; 17:10. [PMID: 28245824 PMCID: PMC5331645 DOI: 10.1186/s12898-017-0120-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 02/20/2017] [Indexed: 11/17/2022] Open
Abstract
Background At high densities, terrestrial and marine species often employ alternate reproductive tactics (ARTs) to maximize reproductive benefits. We describe ARTs in a high-density and unfished spawning aggregation of the squaretail grouper (Plectropomus areolatus) in Lakshadweep, India. Results As previously reported for this species, territorial males engage in pair-courtship, which is associated with a pair-spawning tactic. Here, we document a previously unreported school-courtship tactic; where territorial males court multiple females in mid-water schools, which appears to culminate in a unique ‘school-spawning’ tactic. Courtship tactics were conditional on body size, local mate density and habitat, likely associated with changing trade-offs between potential mating opportunities and intra-sexual competition. Counter-intuitively, the aggregation showed a habitat-specific inverse size-assortment: large males courted small females on the reef slope while small males courted equal-sized or larger females on the shelf. These patterns remained stable across two years of observation at high, unfished densities. Conclusions These unique density-dependent behaviours may disappear from this aggregation as overall densities decline due to increasing commercial fishing pressure, with potentially large consequences for demographics and fitness. Electronic supplementary material The online version of this article (doi:10.1186/s12898-017-0120-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Rucha Karkarey
- Oceans and Coasts Program, Nature Conservation Foundation, 3076/5, 4th Cross, Gokulam Park, Mysore, Karnataka, 570002, India. .,Manipal University, Manipal, Karnataka, 576104, India.
| | - Amod Zambre
- Post-graduate Programme in Wildlife Biology and Conservation, National Centre for Biological Sciences-Wildlife Conservation Society, Bangalore, Karnataka, India
| | - Kavita Isvaran
- Centre for Ecological Sciences, Indian Institute of Science, Bangalore, Karnataka, India
| | - Rohan Arthur
- Oceans and Coasts Program, Nature Conservation Foundation, 3076/5, 4th Cross, Gokulam Park, Mysore, Karnataka, 570002, India.,Centre d'Estudis Avançats de Blanes (CSIC), Blanes, Spain
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16
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Chuard PJ, Brown GE, Grant JW. The effects of adult sex ratio on mating competition in male and female guppies (Poecilia reticulata) in two wild populations. Behav Processes 2016; 129:1-10. [DOI: 10.1016/j.beproc.2016.05.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Revised: 05/03/2016] [Accepted: 05/05/2016] [Indexed: 10/21/2022]
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17
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Mokkonen M, Koskela E, Mappes T, Mills SC. Evolutionary Conflict Between Maternal and Paternal Interests: Integration with Evolutionary Endocrinology. Integr Comp Biol 2016; 56:146-58. [DOI: 10.1093/icb/icw053] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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18
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Mandal B, Kumar R, Jayasankar P. Efficacy of exogenous hormone (GnRHa) for induced breeding of climbing perch Anabas testudineus (Bloch, 1792) and influence of operational sex ratio on spawning success. Anim Reprod Sci 2016; 171:114-20. [PMID: 27346586 DOI: 10.1016/j.anireprosci.2016.06.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2016] [Revised: 06/01/2016] [Accepted: 06/10/2016] [Indexed: 11/30/2022]
Abstract
The climbing perch, Anabas testudineus, is an air-breathing fish having great consumer preference as a food fish and is considered a prime candidate species for aquaculture. Spawning success is an important issue while using hormones for captive induced breeding. In the first experiment, a trial was conducted to assess the efficacy of a synthetic Gonadotropin Releasing Hormone analog (sGnRHa) on the spawning success of climbing perch. Female fish were administered six different doses each with a single intramuscular injection of sGnRHa hormone at 0.002 (TOD1), 0.005 (TOD2), 0.01 (TOD3), 0.015 (TOD4), 0.02 (TOD5), 0.03 (TOD6) μg/g body weight. Similarly, males were administered half of the hormone dose of females in all the respective treatment groups. The greatest (P<0.05) relative fecundity (715.13±15.0 eggs/g female body weight) and fertilization percentage rates (93.1±8.0%) occurred when female fish were treated at the 0.015μg/g body weight dose. There was a reduction in relative fecundity and hatching rate in female fish injected with the largest dose (1.5μL/g body weight) of sGnRHa. A second experiment was conducted to assess the effect of a different male-female ratio on optimum spawning success in climbing perch. For this study a different female to male ratio (1:1, 1:2, 1:3 and 1:4) and male to female ratio (1:1, 1:2 and 1:3) were used. There were a greater (P<0.05) relative fecundity (886.62±17.9 eggs/g female body weight), fertilization (98±6.7%) and hatching (99±5.4%) rates with the female to male ratio of 1:2. This indicated that the hormone dose of 0.015μg/g body weight and a female-male ratio of 1:2 are optimal for enhanced spawning success in the climbing perch.
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Affiliation(s)
- Babita Mandal
- ICAR-Central Institute of Brackishwater Aquaculture, Chennai 600028, India
| | - Rajesh Kumar
- ICAR-Central Institute of Freshwater Aquaculture, Bhubaneswar, Odisha 751002, India.
| | - P Jayasankar
- ICAR-Central Institute of Freshwater Aquaculture, Bhubaneswar, Odisha 751002, India
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19
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Muramatsu D, Koga T. Fighting with an unreliable weapon: opponent choice and risk avoidance in fiddler crab contests. Behav Ecol Sociobiol 2016. [DOI: 10.1007/s00265-016-2094-2] [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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20
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Size Dependent Male Reproductive Tactic in the Two-Spotted Goby (Gobiusculus flavescens). PLoS One 2015; 10:e0143487. [PMID: 26642324 PMCID: PMC4674270 DOI: 10.1371/journal.pone.0143487] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Accepted: 11/05/2015] [Indexed: 11/27/2022] Open
Abstract
Male investment in testes and sperm duct gland in the polygamous nest breeding
two-spotted goby Gobiusculus flavescens (Fabricius) was
investigated in relation to time in reproductive season and individual physical
parameters. This small teleost fish is most likely the most abundant species
found along the rocky shores of the North East Atlantic. The two-spotted goby
has a single reproductive season, during which nest-caring males can raise
several clutches of offspring. According to the literature the males are on
average larger than the females. Here we report for the first time a population
showing a reversal of this trend, with males on average being smaller than
females, a difference likely caused by a large proportion of small males. Early
in the breeding season these small males have typical sneaker characters, with
relatively large testes and small seminal duct glands compared to the larger
dominant territorial males. The presence of these two alternative male
reproductive tactics is confirmed by histological studies, which shows the
presence of sperm in the sperm duct glands (SDG) of smaller males, but not in
the SDG of intermediate and larger males. To our knowledge, males with typical
sneaker characters have not been reported in earlier studied populations of
two-spotted goby. Interestingly we found that testes investment declined
significantly over the course of the breeding season, and that this reduction
was significantly more pronounced in small compared to the large males. Further,
a significant increase in seminal duct gland (SDG) mass was observed for the
smaller males over the breeding season. We propose that this indicates a
possible shift in mating tactic by smaller males from a parasitic to a
nest-holding tactic over the course of the breeding season. Thus, the observed
size dependent plasticity in investment in SDG over time suggests that the
reproductive tactic of G. flavescens is
conditional, and possibly influenced by mate availability and male—male
competition.
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21
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Holveck MJ, Gauthier AL, Nieberding CM. Dense, small and male-biased cages exacerbate male–male competition and reduce female choosiness in Bicyclus anynana. Anim Behav 2015. [DOI: 10.1016/j.anbehav.2015.03.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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22
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Schacht R, Borgerhoff Mulder M. Sex ratio effects on reproductive strategies in humans. ROYAL SOCIETY OPEN SCIENCE 2015; 2:140402. [PMID: 26064588 PMCID: PMC4448795 DOI: 10.1098/rsos.140402] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 12/08/2014] [Indexed: 05/10/2023]
Abstract
Characterizations of coy females and ardent males are rooted in models of sexual selection that are increasingly outdated. Evolutionary feedbacks can strongly influence the sex roles and subsequent patterns of sex differentiated investment in mating effort, with a key component being the adult sex ratio (ASR). Using data from eight Makushi communities of southern Guyana, characterized by varying ASRs contingent on migration, we show that even within a single ethnic group, male mating effort varies in predictable ways with the ASR. At male-biased sex ratios, men's and women's investment in mating effort are indistinguishable; only when men are in the minority are they more inclined towards short-term, low investment relationships than women. Our results support the behavioural ecological tenet that reproductive strategies are predictable and contingent on varying situational factors.
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Affiliation(s)
- Ryan Schacht
- Department of Anthropology, University of Utah, Salt Lake City, UT 84112, USA
- Author for correspondence: Ryan Schacht e-mail:
| | - Monique Borgerhoff Mulder
- Department of Anthropology, University of California-Davis, Davis, CA 95616, USA
- Graduate Group in Ecology, University of California-Davis, Davis, CA 95616, USA
- Center for Population Biology, University of California-Davis, Davis, CA 95616, USA
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23
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Cogliati KM, Mistakidis AF, Marentette JR, Lau A, Bolker BM, Neff BD, Balshine S. Comparing population level sexual selection in a species with alternative reproductive tactics. Behav Ecol 2014. [DOI: 10.1093/beheco/aru147] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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25
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Michálková V, Ondračková M. Experimental evidence for parasite-induced over-winter mortality in juvenile Rhodeus amarus. JOURNAL OF FISH BIOLOGY 2014; 84:1377-1388. [PMID: 24773537 DOI: 10.1111/jfb.12363] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 01/30/2014] [Indexed: 06/03/2023]
Abstract
In this study, the effects of the eye fluke Diplostomum pseudospathaceum (Trematoda) infection on over-winter survival of young-of-the-year (YOY) European bitterling Rhodeus amarus (Cyprinidae) were examined between September 2010 and April 2011. The fish were reared in semi-natural conditions to ensure that results were not confounded by other parasite infections. The cumulative mortality of R. amarus from November until April was significantly higher in D. pseudospathaceum-infected fish (57·3%) compared to controls (42·1%). Infection of the parental generation did not have any effect on the mortality of juveniles. The results indicate that D. pseudospathaceum infection increases over-winter mortality of YOY R. amarus. The possible mechanisms causing mortality are discussed.
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Affiliation(s)
- V Michálková
- Institute of Vertebrate Biology, v.v.i., Academy of Sciences of the Czech Republic, Květná 8, 603 65, Brno, Czech Republic; Department of Botany and Zoology, Faculty of Science, Masaryk University, Kotlářská 2, 611 37, Brno, Czech Republic
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27
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The effect of social environment on alternative mating tactics in male Endler's guppy, Poecilia wingei. Anim Behav 2014. [DOI: 10.1016/j.anbehav.2013.12.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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28
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Mobley KB, Abou Chakra M, Jones AG. No evidence for size-assortative mating in the wild despite mutual mate choice in sex-role-reversed pipefishes. Ecol Evol 2013; 4:67-78. [PMID: 24455162 PMCID: PMC3894889 DOI: 10.1002/ece3.907] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Revised: 11/05/2013] [Accepted: 11/10/2013] [Indexed: 11/30/2022] Open
Abstract
Size-assortative mating is a nonrandom association of body size between members of mating pairs and is expected to be common in species with mutual preferences for body size. In this study, we investigated whether there is direct evidence for size-assortative mating in two species of pipefishes, Syngnathus floridae and S. typhle, that share the characteristics of male pregnancy, sex-role reversal, and a polygynandrous mating system. We take advantage of microsatellite-based “genetic-capture” techniques to match wild-caught females with female genotypes reconstructed from broods of pregnant males and use these data to explore patterns of size-assortative mating in these species. We also develop a simulation model to explore how positive, negative, and antagonistic preferences of each sex for body size affect size-assortative mating. Contrary to expectations, we were unable to find any evidence of size-assortative mating in either species at different geographic locations or at different sampling times. Furthermore, two traits that potentially confer a fitness advantage in terms of reproductive success, female mating order and number of eggs transferred per female, do not affect pairing patterns in the wild. Results from model simulations demonstrate that strong mating preferences are unlikely to explain the observed patterns of mating in the studied populations. Our study shows that individual mating preferences, as ascertained by laboratory-based mating trials, can be decoupled from realized patterns of mating in the wild, and therefore, field studies are also necessary to determine actual patterns of mate choice in nature. We conclude that this disconnect between preferences and assortative mating is likely due to ecological constraints and multiple mating that may limit mate choice in natural populations.
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Affiliation(s)
- Kenyon B Mobley
- Max Planck Institute of Evolutionary Biology August-Thienemann Str. 2, Plön, 24306, Germany
| | - Maria Abou Chakra
- Max Planck Institute of Evolutionary Biology August-Thienemann Str. 2, Plön, 24306, Germany
| | - Adam G Jones
- Department of Biology, Texas A&M University 3258 TAMU, College Station, Texas, 77843, USA
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29
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Rios Moura R, Peixoto PEC. The effect of operational sex ratio on the opportunity for sexual selection: a meta-analysis. Anim Behav 2013. [DOI: 10.1016/j.anbehav.2013.07.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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30
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Liao CP, Yu D, Chen YY, Liu HZ. Reproductive behavior of the male rose bitterling Rhodeus ocellatus as influenced by the operational sex ratio. Zool Stud 2013. [DOI: 10.1186/1810-522x-52-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Abstract
Background
Game theory predicts that as the operational sex ratio (OSR; the ratio of sexually active males to fertilizable females) increases, reproductive males may adopt alternative reproductive behaviors. Empirical studies indicated that alternative behaviors may differ for different species. In the present study, we investigated the influence of different male-biased OSRs on male reproductive behaviors shown by a freshwater fish, the rose bitterling Rhodeus ocellatus.
Results
Six levels of the OSR (1:1, 2:1, 3:1, 5:1, 7:1, and 9:1) were established, and male leading, aggression, and preoviposition ejaculation behaviors were recorded. Our experiments showed that at low OSRs, the leading behavior of male rose bitterling increased with an increasing OSR, reaching a maximum at an OSR of 3:1, and then decreased as the OSR further increased. In contrast, aggression and preoviposition ejaculation behavior continually increased with an increasing OSR. Notably, males possibly lost their territorial position to other males and became sneakers when facing more rivals.
Conclusions
These observations suggest that at lower OSRs, male rose bitterling mainly rely on leading behavior, while at higher OSRs, they increasingly adopt aggression and preoviposition ejaculation. Therefore, for the rose bitterling, (1) decreased leading behavior and (2) increased aggression and preoviposition ejaculation are two alternative responses in the face of an increasing OSR, which is a more straightforward strategy for facing an increased risk of sperm competition than that adopted by its congener, the European bitterling.
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Aronsen T, Berglund A, Mobley KB, Ratikainen II, Rosenqvist G. SEX RATIO AND DENSITY AFFECT SEXUAL SELECTION IN A SEX-ROLE REVERSED FISH. Evolution 2013; 67:3243-57. [DOI: 10.1111/evo.12201] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Accepted: 06/13/2013] [Indexed: 11/30/2022]
Affiliation(s)
- Tonje Aronsen
- Department of Biology, Centre for Biodiversity Dynamics; Norwegian University of Science and Technology; NO-7491 Trondheim Norway
| | - Anders Berglund
- Department of Ecology and Genetics/Animal Ecology; Uppsala University; SE-752 36 Uppsala Sweden
| | - Kenyon B. Mobley
- Department of Evolutionary Ecology; Max Planck Institute for Evolutionary Biology; 24306 Plön Germany
| | - Irja I. Ratikainen
- Department of Biology, Centre for Biodiversity Dynamics; Norwegian University of Science and Technology; NO-7491 Trondheim Norway
| | - Gunilla Rosenqvist
- Department of Biology, Centre for Biodiversity Dynamics; Norwegian University of Science and Technology; NO-7491 Trondheim Norway
- University of Gotland; SE-621 67 Visby Sweden
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32
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Wacker S, Mobley K, Forsgren E, Myhre LC, de Jong K, Amundsen T. OPERATIONAL SEX RATIO BUT NOT DENSITY AFFECTS SEXUAL SELECTION IN A FISH. Evolution 2013; 67:1937-49. [DOI: 10.1111/evo.12092] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Accepted: 01/24/2013] [Indexed: 01/27/2023]
Affiliation(s)
- Sebastian Wacker
- Department of Biology; Norwegian University of Science and Technology; 7491 Trondheim Norway
| | - Kenyon Mobley
- Department of Biology; Norwegian University of Science and Technology; 7491 Trondheim Norway
- Max Planck Institute of Evolutionary Biology; 24306 Plön Germany
| | | | - Lise Cats Myhre
- Department of Biology; Norwegian University of Science and Technology; 7491 Trondheim Norway
| | - Karen de Jong
- Department of Biology; Norwegian University of Science and Technology; 7491 Trondheim Norway
| | - Trond Amundsen
- Department of Biology; Norwegian University of Science and Technology; 7491 Trondheim Norway
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Aronsen T, Mobley K, Berglund A, Sundin J, Billing A, Rosenqvist G. The operational sex ratio and density influence spatial relationships between breeding pipefish. Behav Ecol 2013. [DOI: 10.1093/beheco/art019] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Weir LK. Male–male competition and alternative male mating tactics influence female behavior and fertility in Japanese medaka (Oryzias latipes). Behav Ecol Sociobiol 2012. [DOI: 10.1007/s00265-012-1438-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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36
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Kokko H, Klug H, Jennions MD. Unifying cornerstones of sexual selection: operational sex ratio, Bateman gradient and the scope for competitive investment. Ecol Lett 2012; 15:1340-1351. [PMID: 22925080 DOI: 10.1111/j.1461-0248.2012.01859.x] [Citation(s) in RCA: 128] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Revised: 05/10/2012] [Accepted: 07/23/2012] [Indexed: 11/28/2022]
Abstract
What explains variation in the strength of sexual selection across species, populations or differences between the sexes? Here, we show that unifying two well-known lines of thinking provides the necessary conceptual framework to account for variation in sexual selection. The Bateman gradient and the operational sex ratio (OSR) are incomplete in complementary ways: the former describes the fitness gain per mating and the latter the potential difficulty of achieving it. We combine this insight with an analysis of the scope for sexually selected traits to spread despite naturally selected costs. We explain why the OSR sometimes does not affect the strength of sexual selection. An explanation of sexual selection becomes more logical when a long 'dry time' ('time out', recovery after mating due to e.g. parental care) is understood to reduce the expected time to the next mating when in the mating pool (i.e. available to mate again). This implies weaker selection to shorten the wait. An integrative view of sexual selection combines an understanding of the origin of OSR biases with how they are reflected in the Bateman gradient, and how this can produce selection for mate acquisition traits despite naturally selected costs.
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Affiliation(s)
- Hanna Kokko
- Centre of Excellence in Biological Interactions, Division of Ecology, Evolution & Genetics, Research School of Biology, Australian National University, Canberra, ACT 0200, Australia
| | - Hope Klug
- Department of Biological & Environmental Sciences, University of Tennessee Chattanooga, 215 Holt Hall, Dept 2653, 615 McCallie Aven, Chattanooga, TN, 37403, USA
| | - Michael D Jennions
- Centre of Excellence in Biological Interactions, Division of Ecology, Evolution & Genetics, Research School of Biology, Australian National University, Canberra, ACT 0200, Australia
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Wacker S, de Jong K, Forsgren E, Amundsen T. Large males fight and court more across a range of social environments: an experiment on the two spotted goby Gobiusculus flavescens. JOURNAL OF FISH BIOLOGY 2012; 81:21-34. [PMID: 22747802 DOI: 10.1111/j.1095-8649.2012.03296.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The present study explored how male size relates to mating competition across a natural range of male and female densities in the two-spotted goby Gobiusculus flavescens. Across this range of social environments, large males were more than twice as likely as small ones to chase other males, to become nest-holders, and to court females, but large males were not significantly more likely to engage in agonistic fin displays. Overall, the study showed that large males court and fight more than small ones across a wide, yet natural, span of social environments. Having a large body size appears to confer competitive advantage for males in any social environment of the study species. Further studies are needed to disentangle whether the benefit of large size is mainly in competition over resources, over matings as such, or both.
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Affiliation(s)
- S Wacker
- Department of Biology, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway.
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Changes in reproductive life-history strategies in response to nest density in a shell-brooding cichlid, Telmatochromis vittatus. Naturwissenschaften 2011; 99:23-31. [PMID: 22089034 DOI: 10.1007/s00114-011-0864-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2011] [Revised: 10/31/2011] [Accepted: 11/03/2011] [Indexed: 10/15/2022]
Abstract
To determine whether the appearance of a reproductively parasitic tactic varies, and how this variation affects territorial males of the Lake Tanganyika cichlid fish Telmatochromis vittatus, we examined the reproductive ecology of territorial males in Mtondwe and compared it with that of a neighboring Wonzye population, where nest density differs from that at Mtondwe. In Wonzye, with high nest density, male tactics change with their body size from a territorial to a non-territorial parasitic tactic called piracy in which they conquer several nests defended by territorial males and take over the nests while females are spawning. These "pirate" males could decrease the costs incurred by travelling among nests by exclusively targeting aggregations of nests in close proximity while avoiding separate nests. Territorial males in Wonzye sacrifice the potential higher attractiveness offered by large nests and instead compete for nests farther from neighbors on which pirates less frequently intrude. In contrast, the Mtondwe population had lower nest density and piracy was absent. Given that the success of piracy depends on the close proximity of nests, nest density is likely responsible for the observed variation in the occurrence of piracy between the two populations. Furthermore, in Mtondwe, territorial males competed for larger nests and were smaller than the territorial males in Wonzye. Thus, this lower nest density may free territorial males from the selection pressures for increased size caused by both defense against nest piracy and the need to develop into pirates as they grow.
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Weir LK, Grant JWA, Hutchings JA. The influence of operational sex ratio on the intensity of competition for mates. Am Nat 2011; 177:167-76. [PMID: 21460553 DOI: 10.1086/657918] [Citation(s) in RCA: 188] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The evolution and maintenance of secondary sexual characteristics and behavior are heavily influenced by the variance in mating success among individuals in a population. The operational sex ratio (OSR) is often used as a predictor of the intensity of competition for mates, as it describes the relative number of males and females who are ready to mate. We investigate changes in aggression, courtship, mate guarding, and sperm release as a function of changes in the OSR using meta-analytic techniques. As the OSR becomes increasingly biased, aggression increases as competitors attempt to defend mates, but this aggression begins to decrease at an OSR of 1.99, presumably due to the increased costs of competition as rivals become more numerous. Sperm release follows a similar but not significant trend. By contrast, courtship rate decreases as the OSR becomes increasingly biased, whereas mate guarding and copulation duration increase. Overall, predictable behavioral changes occur in response to OSR, although the nature of the change is dependent on the type of mating behavior. These results suggest considerable flexibility of mating system structure within species, which can be predicted by OSR and likely results in variation in the strength of sexual selection.
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Affiliation(s)
- Laura K Weir
- Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada.
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Intrasexual competition and courtship in female and male Japanese medaka, Oryzias latipes: effects of operational sex ratio and density. Anim Behav 2010. [DOI: 10.1016/j.anbehav.2010.07.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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41
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Population and individual consequences of breeding resource availability in the European bitterling (Rhodeus amarus). Behav Ecol Sociobiol 2010. [DOI: 10.1007/s00265-010-0921-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Weir LK, Grant JWA, Hutchings JA. Patterns of Aggression and Operational Sex Ratio Within Alternative Male Phenotypes in Atlantic Salmon. Ethology 2010. [DOI: 10.1111/j.1439-0310.2009.01723.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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43
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de Jong K, Wacker S, Amundsen T, Forsgren E. Do operational sex ratio and density affect mating behaviour? An experiment on the two-spotted goby. Anim Behav 2009. [DOI: 10.1016/j.anbehav.2009.08.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Reichard M, Ondračková M, Bryjová A, Smith C, Bryja J. BREEDING RESOURCE DISTRIBUTION AFFECTS SELECTION GRADIENTS ON MALE PHENOTYPIC TRAITS: EXPERIMENTAL STUDY ON LIFETIME REPRODUCTIVE SUCCESS IN THE BITTERLING FISH (RHODEUS AMARUS). Evolution 2009; 63:377-90. [DOI: 10.1111/j.1558-5646.2008.00572.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Pomfret JC, Knell RJ. Crowding, sex ratio and horn evolution in a South African beetle community. Proc Biol Sci 2008; 275:315-21. [PMID: 18048281 DOI: 10.1098/rspb.2007.1498] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Sexually selected ornaments and weapons are exceptionally variable, even between closely related species. It has long been recognized that some of this diversity can be explained by differences in mating systems between species, but there remains substantial variation between species with similar mating systems. We investigated the roles of sex ratio (measured as operational sex ratio, OSR) and population density (measured as mean male crowding, a measure indicating the average number of conspecific males that an individual male animal will encounter) in determining horn presence in a community of South African dung beetles. Analysis of data from 14 species using a generalized least-squares model incorporating phylogenetic influences found that both OSR and mean crowding were significant predictors of horn presence, with hornless species tending to show female-biased sex ratios and high levels of crowding. The influence of mean crowding on horn diversity between species probably reflects the difficulty of guarding and monopolizing females when many competitors are present, meaning that males who adopt 'scramble' tactics tend to be favoured.
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Affiliation(s)
- Joanne C Pomfret
- School of Biological and Chemical Sciences, Queen Mary, University of London, Mile End Road, London E1 4NS, UK
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Biased sex ratio and low population density increase male mating success in the bug Nysius huttoni (Heteroptera: Lygaeidae). Naturwissenschaften 2008; 96:87-91. [PMID: 18839127 DOI: 10.1007/s00114-008-0455-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2008] [Revised: 09/15/2008] [Accepted: 09/18/2008] [Indexed: 10/21/2022]
Abstract
Demographic factors such as operational sex ratio (OSR) and local population density (LPD) are temporally and spatially dynamic in the natural environment but the influence of these variables on male mating success and the mechanisms behind it are still poorly understood and highly controversial. Here, we manipulated the OSR and LPD of a seed bug, Nysius huttoni, and carried out a series of mating trials to test how these variables affected male mating success. The two demographic factors had no significant interactions, suggesting that they affect male mating success independently in N. huttoni. In this species male mating success was significantly higher in both male- and female-biased OSR than in even OSR. It is suggested that, in male-biased OSR, the increased intensity of competition and interference does not result in lower male mating success; rather, males may make more effort in courting and females may have more chance to encounter better males, resulting in higher male mating success. In female-biased OSR, females may become less choosy and less likely to reject male mating attempt, leading to the higher male mating success. Lower male mating success in N. huttoni in high LPD may be due to increased interference between males and/or delayed female receptiveness for mating. OSR had a stronger effect on male mating success than LPD in N. huttoni, suggesting that OSR and LPD affect mating success in different ways and intensities.
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Abstract
Conventional sex roles imply caring females and competitive males. The evolution of sex role divergence is widely attributed to anisogamy initiating a self-reinforcing process. The initial asymmetry in pre-mating parental investment (eggs vs. sperm) is assumed to promote even greater divergence in post-mating parental investment (parental care). But do we really understand the process? Trivers [Sexual Selection and the Descent of Man 1871-1971 (1972), Aldine Press, Chicago] introduced two arguments with a female and male perspective on whether to care for offspring that try to link pre-mating and post-mating investment. Here we review their merits and subsequent theoretical developments. The first argument is that females are more committed than males to providing care because they stand to lose a greater initial investment. This, however, commits the 'Concorde Fallacy' as optimal decisions should depend on future pay-offs not past costs. Although the argument can be rephrased in terms of residual reproductive value when past investment affects future pay-offs, it remains weak. The factors likely to change future pay-offs seem to work against females providing more care than males. The second argument takes the reasonable premise that anisogamy produces a male-biased operational sex ratio (OSR) leading to males competing for mates. Male care is then predicted to be less likely to evolve as it consumes resources that could otherwise be used to increase competitiveness. However, given each offspring has precisely two genetic parents (the Fisher condition), a biased OSR generates frequency-dependent selection, analogous to Fisherian sex ratio selection, that favours increased parental investment by whichever sex faces more intense competition. Sex role divergence is therefore still an evolutionary conundrum. Here we review some possible solutions. Factors that promote conventional sex roles are sexual selection on males (but non-random variance in male mating success must be high to override the Fisher condition), loss of paternity because of female multiple mating or group spawning and patterns of mortality that generate female-biased adult sex ratios (ASR). We present an integrative model that shows how these factors interact to generate sex roles. We emphasize the need to distinguish between the ASR and the operational sex ratio (OSR). If mortality is higher when caring than competing this diminishes the likelihood of sex role divergence because this strongly limits the mating success of the earlier deserting sex. We illustrate this in a model where a change in relative mortality rates while caring and competing generates a shift from a mammalian type breeding system (female-only care, male-biased OSR and female-biased ASR) to an avian type system (biparental care and a male-biased OSR and ASR).
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Affiliation(s)
- Hanna Kokko
- Laboratory of Ecological and Evolutionary Dynamics, Department of Biological and Environmental Science, University of Helsinki, Helsinki, Finland.
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Moorhouse TP, Macdonald DW. What limits male range sizes at different population densities? Evidence from three populations of water voles. J Zool (1987) 2008. [DOI: 10.1111/j.1469-7998.2007.00399.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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50
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Fitze PS, Le Galliard JF. Operational sex ratio, sexual conflict and the intensity of sexual selection. Ecol Lett 2008; 11:432-9. [PMID: 18279355 DOI: 10.1111/j.1461-0248.2008.01158.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Modern sexual selection theory indicates that reproductive costs rather than the operational sex ratio predict the intensity of sexual selection. We investigated sexual selection in the polygynandrous common lizard Lacerta vivipara. This species shows male aggression, causing high mating costs for females when adult sex ratios (ASR) are male-biased. We manipulated ASR in 12 experimental populations and quantified the intensity of sexual selection based on the relationship between reproductive success and body size. In sharp contrast to classical sexual selection theory predictions, positive directional sexual selection on male size was stronger and positive directional selection on female size weaker in female-biased populations than in male-biased populations. Thus, consistent with modern theory, directional sexual selection on male size was weaker in populations with higher female mating costs. This suggests that the costs of breeding, but not the operational sex ratio, correctly predicted the strength of sexual selection.
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Affiliation(s)
- Patrick S Fitze
- Museo Nacional de Ciencias Naturales (MNCN-CSIC), Department of Biodiversity and Evolutionary Biology, C/ José Gutiérrez Abascal 2, Madrid 28006, Spain.
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