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Hong X, Xiang Y, Wang Z, Li J, Zou R, Gao P. Contextual modulation of the red-attractiveness effect: Differences in affiliation and competitive settings. Acta Psychol (Amst) 2024; 243:104171. [PMID: 38320412 DOI: 10.1016/j.actpsy.2024.104171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 01/31/2024] [Accepted: 02/01/2024] [Indexed: 02/08/2024] Open
Abstract
Color is not just about aesthetics but also communicates specific information and has important implications for psychological functioning. It has been shown that the color red enhances perceived attractiveness when evaluating the opposite sex, which we call the red-attractiveness effect. However, few studies have attached importance to the social context in which attractiveness ratings are made, which means that the red-attractiveness effect is rarely explained by analyzing the role of social context. We conducted two experiments to test the red-attractiveness effect in Chinese culture and the influence of context (affiliation or competitive) on the red-attractiveness effect. Experiment 1 (160 Chinese college students, 80 males) showed that the opposite-sex target in red, compared to white, was rated more attractive, and the red-attractiveness effect was applicable to Chinese culture. Experiment 2 (480 Chinese college students, 240 males) found that perceived attractiveness was strengthened in the affiliation context and weakened in the competitive context, that is, the main effect of context was significant. We did not find any significant effect of the color red in either context, that is, the color main effect was not significant. However, the results indicate that red can enhance perceived attractiveness when evaluating the opposite sex. This study demonstrates that the red attractiveness effect may exist in different cultural backgrounds and contexts.
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Affiliation(s)
- Xiaobin Hong
- Department of Psychology, Wuhan Sports University, Wuhan 430079, China; Hubei Key Laboratory of Exercise Training and Monitoring, Wuhan Sports University, Wuhan 430079, China
| | - Yuxiu Xiang
- Department of Psychology, Wuhan Sports University, Wuhan 430079, China
| | - Zhonghuan Wang
- Department of Psychology, Wuhan Sports University, Wuhan 430079, China
| | - Jinkun Li
- Department of Psychology, Wuhan Sports University, Wuhan 430079, China
| | - Rong Zou
- Department of Psychology, Wuhan Sports University, Wuhan 430079, China; Hubei Key Laboratory of Exercise Training and Monitoring, Wuhan Sports University, Wuhan 430079, China
| | - Ping Gao
- Research Center for Sports and Health Innovation and Development, Wuhan Sports University, Wuhan, China.
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2
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Sobral G, Dubuc C, Winters S, Ruiz-Lambides A, Emery Thompson M, Maestripieri D, Milich KM. Facial and genital color ornamentation, testosterone, and reproductive output in high-ranking male rhesus macaques. Sci Rep 2024; 14:2621. [PMID: 38297064 PMCID: PMC10831099 DOI: 10.1038/s41598-024-52400-0] [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: 10/20/2023] [Accepted: 01/18/2024] [Indexed: 02/02/2024] Open
Abstract
Males in many vertebrate species have colorful ornaments that evolved by sexual selection. The role of androgens in the genesis and maintenance of these signals is unclear. We studied 21 adult high-ranking male rhesus macaques from nine social groups in the free-ranging population on Cayo Santiago, Puerto Rico, and analyzed facial and genital skin luminance and redness, fecal androgens, rates of mating behaviors, and offspring sired. Facial and genital coloration varied in relation to age, mating behavior, reproductive success, and testosterone concentration. Our results indicate that skin coloration in high-ranking male rhesus macaques is a sexually-selected trait mediated by androgens. These results add to the growing literature on the proximate and ultimate causes of male sexual signals and highlight the need to examine how these characteristics change with age in other species.
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Affiliation(s)
- Gisela Sobral
- Department of Anthropology, Washington University in St. Louis, St. Louis, MO, USA
- Instituto de Biodiversidade e Sustentabilidade (NUPEM/UFRJ), Macaé, RJ, Brazil
| | - Constance Dubuc
- Department of Anthropology, New York University, New York, NY, USA
| | - Sandra Winters
- Department of Anthropology, New York University, New York, NY, USA
- Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | | | | | | | - Krista M Milich
- Department of Anthropology, Washington University in St. Louis, St. Louis, MO, USA.
- Institute for Mind and Biology, University of Chicago, Chicago, IL, USA.
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3
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Onaga J, Soma M. Eyes of love: Java sparrows increase eye ring conspicuousness when pair-bonded. PLoS One 2023; 18:e0292074. [PMID: 37878547 PMCID: PMC10599526 DOI: 10.1371/journal.pone.0292074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 09/12/2023] [Indexed: 10/27/2023] Open
Abstract
Conspicuous facial features, such as blushing in primates, can communicate social/emotional/physiological states in animals. However, the role of bare facial features is less well studied in birds than in humans or primates. We investigate the Java sparrow, which is characterised by conspicuous rings of swollen and blushed bare skin around the eye. Eye rings show no clear sex difference, although the swelling is associated with breeding. Java sparrows are socially monogamous, with mutual courtships and long-term pair-bonding. Therefore, it is plausible that eye rings function in within-pair communication. Specifically, do eye rings reflect psychophysiological conditions after pair formation? We assessed variations in ring thickness in pair-bonded birds and compared them with single birds and pairs of non-bonded individuals. Over the 12-week experimental period, pair-bonded males and females had an increased ring thickness, unlike the controls. We suggest eye rings convey breeding motivations or serve as fertility signals. This would be of great importance for ensuring reproductive synchrony in tropical birds like the Java sparrow. Our results contribute to understanding the evolution of facial ornamentation in birds, which was often overlooked in the past studies.
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Affiliation(s)
- Jenna Onaga
- Biosystems Science Course, Graduate School of Life Science, Hokkaido University, Sapporo, Japan
| | - Masayo Soma
- Department of Biology, Faculty of Science, Hokkaido University, Sapporo, Japan
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4
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Wilson VAD, Masilkova M. Does the primate face cue personality? PERSONALITY NEUROSCIENCE 2023; 6:e7. [PMID: 38107779 PMCID: PMC10725780 DOI: 10.1017/pen.2023.5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 05/24/2023] [Accepted: 05/31/2023] [Indexed: 12/19/2023]
Abstract
When looking at others, primates primarily focus on the face - detecting the face first and looking at it longer than other parts of the body. This is because primate faces, even without expression, convey trait information crucial for navigating social relationships. Recent studies on primates, including humans, have linked facial features, specifically facial width-to-height ratio (fWHR), to rank and Dominance-related personality traits, suggesting these links' potential role in social decisions. However, studies on the association between dominance and fWHR report contradictory results in humans and variable patterns in nonhuman primates. It is also not clear whether and how nonhuman primates perceive different facial cues to personality traits and whether these may have evolved as social signals. This review summarises the variable facial-personality links, their underlying proximate and evolutionary mechanisms and their perception across primates. We emphasise the importance of employing comparative research, including various primate species and human populations, to disentangle phylogeny from socio-ecological drivers and to understand the selection pressures driving the facial-personality links in humans. Finally, we encourage researchers to move away from single facial measures and towards holistic measures and to complement perception studies using neuroscientific methods.
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Affiliation(s)
- Vanessa A D Wilson
- Department of Comparative Cognition, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland
- Department of Comparative Language Science, University of Zurich, Zurich, Switzerland
- Center for the Interdisciplinary Study of Language Evolution (ISLE), University of Zurich, Zurich, Switzerland
| | - Michaela Masilkova
- Department of Game Management and Wildlife Biology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences, Prague, Czech Republic
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5
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Clive J, Flintham E, Savolainen V. Same-sex sociosexual behaviour is widespread and heritable in male rhesus macaques. Nat Ecol Evol 2023; 7:1287-1301. [PMID: 37429903 DOI: 10.1038/s41559-023-02111-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 06/01/2023] [Indexed: 07/12/2023]
Abstract
Numerous reports have documented the occurrence of same-sex sociosexual behaviour (SSB) across animal species. However, the distribution of the behaviour within a species needs to be studied to test hypotheses describing its evolution and maintenance, in particular whether the behaviour is heritable and can therefore evolve by natural selection. Here we collected detailed observations across 3 yr of social and mounting behaviour of 236 male semi-wild rhesus macaques, which we combined with a pedigree dating back to 1938, to show that SSB is both repeatable (19.35%) and heritable (6.4%). Demographic factors (age and group structure) explained SSB variation only marginally. Furthermore, we found a positive genetic correlation between same-sex mounter and mountee activities, indicating a common basis to different forms of SSB. Finally, we found no evidence of fitness costs to SSB, but show instead that the behaviour mediated coalitionary partnerships that have been linked to improved reproductive success. Together, our results demonstrate that SSB is frequent in rhesus macaques, can evolve, and is not costly, indicating that SSB may be a common feature of primate reproductive ecology.
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Affiliation(s)
- Jackson Clive
- Georgina Mace Centre for the Living Planet, Department of Life Sciences, Silwood Park Campus, Imperial College London, Ascot, UK
| | - Ewan Flintham
- Georgina Mace Centre for the Living Planet, Department of Life Sciences, Silwood Park Campus, Imperial College London, Ascot, UK
| | - Vincent Savolainen
- Georgina Mace Centre for the Living Planet, Department of Life Sciences, Silwood Park Campus, Imperial College London, Ascot, UK.
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6
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Meireles BC, Goldschmidt B, Lopes CA, Demarque KC, Leal GM, Magalhães MS, Souza MB, Cruz RS. Spontaneous Vitiligo in a Captive Rhesus Monkey ( Macaca Mulatta). Comp Med 2023; 73:242-247. [PMID: 37263754 PMCID: PMC10290481 DOI: 10.30802/aalas-cm-22-000091] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 01/31/2023] [Accepted: 02/06/2023] [Indexed: 06/03/2023]
Abstract
Vitiligo affects a significant portion of human and animal populations. The disease causes irregular and multifocal progressive loss of fur, skin, and mucous membrane pigmentation due to the loss or absence of melanocytes. While etiopathogenesis is not completely understood, autoimmunity, environmental, and genetic factors are implicated We present a case report on a 16-y-old female rhesus macaque (Macaca mulatta ) with depigmented areas that are progressively increasing on the skin and coat and are distributed on the head and back. Histopathology revealed alterations compatible with vitiligo characterized by the absence of melanocytes in the epidermis and dermis. The clinical history and complementary exams support this diagnosis.
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Affiliation(s)
- Bárbara Cs Meireles
- Department of Primatology, Institute of Science and Technology in Biomodels (ICTB), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil;,
| | - Beatriz Goldschmidt
- Department of Primatology, Institute of Science and Technology in Biomodels (ICTB), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Cláudia A Lopes
- Department of Primatology, Institute of Science and Technology in Biomodels (ICTB), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Kelly C Demarque
- Laboratory of Cellular Biology (LBC), Oswaldo Cruz Institute (IOC/FIOCRUZ), Rio de Janeiro, Brazil
| | - Gabriel M Leal
- Department of Primatology, Institute of Science and Technology in Biomodels (ICTB), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Mariana S Magalhães
- Department of Primatology, Institute of Science and Technology in Biomodels (ICTB), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Milena B Souza
- Department of Primatology, Institute of Science and Technology in Biomodels (ICTB), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Ricardo S Cruz
- Department of Primatology, Institute of Science and Technology in Biomodels (ICTB), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
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7
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Colby AE, DeCasien AR, Cooper EB, Higham JP. Greater variability in rhesus macaque ( Macaca mulatta) endocranial volume among males than females. Proc Biol Sci 2022; 289:20220728. [PMID: 36350207 PMCID: PMC9653222 DOI: 10.1098/rspb.2022.0728] [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: 04/14/2022] [Accepted: 10/05/2022] [Indexed: 11/11/2023] Open
Abstract
The greater male variability (GMV) hypothesis proposes that traits are more variable among males than females, and is supported by numerous empirical studies. Interestingly, GMV is also observed for human brain size and internal brain structure, a pattern which may have implications for sex-biased neurological and psychiatric conditions. A better understanding of neuroanatomical variability in non-human primates may illuminate whether certain species are appropriate models for these conditions. Here, we tested for sex differences in the variability of endocranial volume (ECV, a proxy for brain size) in a sample of 542 rhesus macaques (Macaca mulatta) from a large pedigreed free-ranging population. We also examined the components of phenotypic variance (additive genetic and residual variance) to tease apart the potential drivers of sex differences in variability. Our results suggest that males exhibit more variable ECVs, and that this pattern reflects either balancing/disruptive selection on male behaviour (associated with alternative male mating strategies) or sex chromosome effects (associated with mosaic patterns of X chromosome gene expression in females), rather than extended neurodevelopment among males. This represents evidence of GMV for brain size in a non-human primate species and highlights the potential of rhesus macaques as a model for sex-biased brain-based disorders.
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Affiliation(s)
- Abigail E. Colby
- Department of Anthropology, New York University, New York, NY, USA
- Department of Anthropology and Archaeology, University of Calgary, Calgary, AB, Canada
| | - Alex R. DeCasien
- Department of Anthropology, New York University, New York, NY, USA
- New York Consortium in Evolutionary Primatology, New York, NY, USA
- Section on Developmental Neurogenomics, National Institutes of Health, Bethesda, MD, USA
| | - Eve B. Cooper
- Department of Anthropology, New York University, New York, NY, USA
- New York Consortium in Evolutionary Primatology, New York, NY, USA
| | - James P. Higham
- Department of Anthropology, New York University, New York, NY, USA
- New York Consortium in Evolutionary Primatology, New York, NY, USA
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8
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Jiang Y, Sheng F, Belkaya N, Platt ML. Oxytocin and testosterone administration amplify viewing preferences for sexual images in male rhesus macaques. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210133. [PMID: 35858095 PMCID: PMC9272140 DOI: 10.1098/rstb.2021.0133] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Social stimuli, like faces, and sexual stimuli, like genitalia, spontaneously attract visual attention in both human and non-human primates. Social orienting behaviour is thought to be modulated by neuropeptides as well as sex hormones. Using a free viewing task in which paired images of monkey faces and anogenital regions were presented simultaneously, we found that male rhesus macaques overwhelmingly preferred to view images of anogenital regions over faces. They were more likely to make an initial gaze shift towards, and spent more time viewing, anogenital regions compared with faces, and this preference was accompanied by relatively constricted pupils. On face images, monkeys mostly fixated on the forehead and eyes. These viewing preferences were found for images of both males and females. Both oxytocin (OT), a neuropeptide linked to social bonding and affiliation, and testosterone (TE), a sex hormone implicated in mating and aggression, amplified the pre-existing orienting bias for female genitalia over female faces; neither treatment altered the viewing preference for male anogenital regions over male faces. Testosterone but not OT increased the probability of monkeys making the first gaze shift towards female anogenital rather than face pictures, with the strongest effects on anogenital images of young and unfamiliar females. Finally, both OT and TE promoted viewing of the forehead region of both female and male faces, which display sexual skins, but decreased the relative salience of the eyes of older males. Together, these results invite the hypothesis that both OT and TE regulate reproductive behaviours by acting as a gain control on the visual orienting network to increase attention to mating-relevant signals in the environment. This article is part of the theme issue ‘Interplays between oxytocin and other neuromodulators in shaping complex social behaviours’.
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Affiliation(s)
- Yaoguang Jiang
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Feng Sheng
- Wharton Neuroscience Initiative, University of Pennsylvania, Philadelphia, PA, 19104, USA
- School of Management and MOE Frontier Science Center for Brain Science & Brain–Machine Integration, Zhejiang University, Hangzhou, Zhejiang, 310058, China
| | - Naz Belkaya
- Champalimaud Center for the Unknown, Lisbon, 1400-038, Portugal
| | - Michael L. Platt
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Department of Psychology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Marketing Department, the Wharton School, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Wharton Neuroscience Initiative, University of Pennsylvania, Philadelphia, PA, 19104, USA
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9
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Cooper EB, Brent LJN, Snyder-Mackler N, Singh M, Sengupta A, Khatiwada S, Malaivijitnond S, Qi Hai Z, Higham JP. The natural history of model organisms: the rhesus macaque as a success story of the Anthropocene. eLife 2022; 11:78169. [PMID: 35801697 PMCID: PMC9345599 DOI: 10.7554/elife.78169] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 07/07/2022] [Indexed: 11/25/2022] Open
Abstract
Of all the non-human primate species studied by researchers, the rhesus macaque (Macaca mulatta) is likely the most widely used across biological disciplines. Rhesus macaques have thrived during the Anthropocene and now have the largest natural range of any non-human primate. They are highly social, exhibit marked genetic diversity, and display remarkable niche flexibility (which allows them to live in a range of habitats and survive on a variety of diets). These characteristics mean that rhesus macaques are well-suited for understanding the links between sociality, health and fitness, and also for investigating intra-specific variation, adaptation and other topics in evolutionary ecology.
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Affiliation(s)
- Eve B Cooper
- Department of Anthropology, New York University, New York, United States
| | | | | | - Mewa Singh
- Biopsychology Laboratory, University of Mysore, Mysuru, India
| | | | - Sunil Khatiwada
- Institute of Genetics and Animal Biotechnology of the Polish Academy of Sciences, Garbatka, Poland
| | | | - Zhou Qi Hai
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, Guangxi Normal University, Guilin, China
| | - James P Higham
- Department of Anthropology, New York University, New York, United States
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10
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11
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Assessing male gelada chest patches: color measurement and physiological mechanisms. Mamm Biol 2022. [DOI: 10.1007/s42991-021-00211-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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12
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Greenberg D, Snyder KP, Filazzola A, Mastromonaco GF, Schoof VAM. Hormonal correlates of male dominance rank, age, and genital colouration in vervet monkey (Chlorocebus pygerythrus). Gen Comp Endocrinol 2022; 316:113948. [PMID: 34826430 DOI: 10.1016/j.ygcen.2021.113948] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 11/02/2021] [Accepted: 11/19/2021] [Indexed: 01/04/2023]
Abstract
Primates are the most colourful members of the Mammalian clade. In vervet monkeys (Chlorocebus pygerythrus), males are characterized by their red penis and blue scrotum. Such colour signals are often used in conspecific communication, and thus could be used to convey signaller condition. We quantified scrotal and penile colour characteristics using digital photographs between May-June 2016 from males in two neighboring groups along the shores of Lake Nabugabo, Uganda. We examined the relationship between fecal hormones, male dominance rank, age (adult vs. immature), and colour. Adult males were higher ranking than immatures, but there were no rank or age differences in fecal hormone levels. Glucocorticoids and androgens were positively correlated in immature, but not adult males. All scrotal characteristics were predicted by age, with adult males having more teal (i.e., less blue, more green) and more luminant scrota. Within adult males, those with higher androgens levels had more saturated blue scrotal colouration and higher-ranking males were more luminant. Penile colouration was also associated with age and rank. High-ranking males had a more saturated red penis, and adult male penile colour was more luminant and bluer than in immature males. Our findings are consistent with previous reports that scrotal colouration advertises sexual or reproductive maturity (i.e., age), but we also find that within adult males, colour also advertises dominance rank and may be mediated by androgen levels. Penile colouration also appears to signal information about male age and dominance rank but does not appear to be mediated by hormones.
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Affiliation(s)
- D Greenberg
- Department of Biology, Faculty of Science, York University, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
| | - K P Snyder
- Department of Biology, Faculty of Science, York University, 4700 Keele Street, Toronto, ON M3J 1P3, Canada
| | - A Filazzola
- Department of Biology, Faculty of Science, York University, 4700 Keele Street, Toronto, ON M3J 1P3, Canada; Department of Biological Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, ON M1C 1A4, Canada
| | - G F Mastromonaco
- Reproductive Sciences Unit, Toronto Zoo, 361A Old Finch Avenue, Toronto, ON M1B 5K7, Canada
| | - V A M Schoof
- Department of Biology, Faculty of Science, York University, 4700 Keele Street, Toronto, ON M3J 1P3, Canada; Bilingual Biology Program, Department of Multidisciplinary Studies, Glendon College, York University, 2275 Bayview Avenue, Toronto, ON M4N 3M6, Canada.
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13
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Caro T, Brockelsby K, Ferrari A, Koneru M, Ono K, Touche E, Stankowich T. The evolution of primate coloration revisited. Behav Ecol 2021. [DOI: 10.1093/beheco/arab029] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Abstract
Primates are noted for their varied and complex pelage and bare skin coloration but the significance of this diverse coloration remains opaque. Using new updated information, novel scoring of coat and skin coloration, and controlling for shared ancestry, we reexamined and extended findings from previous studies across the whole order and the five major clades within it. Across primates, we found (i) direct and indirect evidence for pelage coloration being driven by protective coloration strategies including background matching, countershading, disruptive coloration, and aposematism, (ii) diurnal primates being more colorful, and (iii) the possibility that pelage color diversity is negatively associated with female trichromatic vision; while (iv) reaffirming avoidance of hybridization driving head coloration in males, (v) darker species living in warm, humid conditions (Gloger’s rule), and (vi) advertising to multiple mating partners favoring red genitalia in females. Nonetheless, the importance of these drivers varies greatly across clades. In strepsirrhines and cercopithecoids, countershading is important; greater color diversity may be important for conspecific signaling in more diurnal and social strepsirrhines; lack of female color vision may be associated with colorful strepsirrhines and platyrrhines; whereas cercopithecoids obey Gloger’s rule. Haplorrhines show background matching, aposematism, character displacement, and red female genitalia where several mating partners are available. Our findings emphasize several evolutionary drivers of coloration in this extraordinarily colorful order. Throughout, we used coarse but rigorous measures of coloration, and our ability to replicate findings from earlier studies opens up opportunities for classifying coloration of large numbers of species at a macroevolutionary scale.
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Affiliation(s)
- Tim Caro
- Department of Biological Sciences, University of Bristol, 24 Tyndall Avenue, Bristol BS8 1TQ, UK
- Center for Population Biology, University of California, 1 Shields Avenue, Davis, Davis, CA 95616, USA
| | - Kasey Brockelsby
- Department of Evolution and Ecology, University of California, Davis, 1 Shields Avenue, Davis, CA 95616, USA
| | - Annie Ferrari
- Department of Biological Sciences, University of Bristol, 24 Tyndall Avenue, Bristol BS8 1TQ, UK
| | - Manisha Koneru
- Department of Evolution and Ecology, University of California, Davis, 1 Shields Avenue, Davis, CA 95616, USA
| | - Konatsu Ono
- Department of Animal Biology, University of California, Davis, 1 Shields Avenue, Davis, CA 95616, USA
| | - Edward Touche
- Department of Biological Sciences, University of Bristol, 24 Tyndall Avenue, Bristol BS8 1TQ, UK
| | - Theodore Stankowich
- Department of Biological Sciences, California State University, 1250 Bellflower Boulevard, Long Beach, CA 90840, USA
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14
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Rigaill L, Garcia C. Does male mate choice select for female coloration in a promiscuous primate species? Anim Behav 2021. [DOI: 10.1016/j.anbehav.2021.05.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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15
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Bell RB, Bradley BJ, Kamilar JM. The Evolutionary Ecology of Primate Hair Coloration: A Phylogenetic Approach. J MAMM EVOL 2021. [DOI: 10.1007/s10914-021-09547-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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16
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Fannin LD, Plavcan JM, Daegling DJ, McGraw WS. Oral processing, sexual selection, and size variation in the circumorbital region of Colobus and Piliocolobus. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2021; 175:559-576. [PMID: 33811653 DOI: 10.1002/ajpa.24280] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 01/07/2021] [Accepted: 03/15/2021] [Indexed: 01/17/2023]
Abstract
OBJECTIVES The function of the browridge in primates is a subject of enduring debate. Early studies argued for a role in resisting masticatory stresses, but recent studies have suggested sexual signaling as a biological role. We tested associations between circumorbital form, diet, oral processing, and social behavior in two species of colobus monkey-the king colobus (Colobus polykomos) and western red or bay colobus (Piliocolobus badius). MATERIALS AND METHODS We quantified circumorbital size and dimorphism in a sample of 98 crania. Controlling for age and facial size, we tested whether variation in circumorbital morphology can be explained by variation in diet, oral processing behavior, masticatory muscle size, and mating system. To contextualize our results, we included a broader sample of facial dimorphism for 67 anthropoid species. RESULTS Greater circumorbital thickness is unrelated to the stresses of food processing. King colobus engages in longer bouts of anterior tooth use, chews more per ingestive event, and processes a tougher diet, yet circumorbital thickness of C. polykomos is reduced compared to P. badius. Differences in circumorbital development do not vary with wear or facial size. Greater sexual dimorphism is present in P. badius; comparisons across anthropoids indicated patterns of circumorbital dimorphism were decoupled from overall size dimorphism. CONCLUSIONS The expanded circumorbits of male red colobus monkeys evolved in response to intense male-male competition. This hypothesis is consistent with the pattern across anthropoid primates and highlights the underappreciated role of sexual selection in shaping the primate face.
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Affiliation(s)
- Luke D Fannin
- Department of Anthropology, Dartmouth College, Hanover, New Hampshire, USA.,Graduate Program in Ecology, Evolution, Environment, and Society, Dartmouth College, Hanover, New Hampshire, USA
| | - J Michael Plavcan
- Department of Anthropology, University of Arkansas, Fayetteville, Arkansas, USA
| | - David J Daegling
- Department of Anthropology, University of Florida, Gainesville, Florida, USA
| | - W Scott McGraw
- Department of Anthropology, The Ohio State University, Columbus, Ohio, USA
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17
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Higham JP, Kimock CM, Mandalaywala TM, Heistermann M, Cascio J, Petersdorf M, Winters S, Allen WL, Dubuc C. Female ornaments: is red skin color attractive to males and related to condition in rhesus macaques? Behav Ecol 2021; 32:236-247. [PMID: 33814977 PMCID: PMC7995641 DOI: 10.1093/beheco/araa121] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 10/05/2020] [Accepted: 10/23/2020] [Indexed: 11/14/2022] Open
Abstract
Sexual selection produces extravagant male traits, such as colorful ornaments, via female mate choice. More rarely, in mating systems in which males allocate mating effort between multiple females, female ornaments may evolve via male mate choice. Females of many anthropoid primates exhibit ornaments that indicate intraindividual cyclical fertility, but which have also been proposed to function as interindividual quality signals. Rhesus macaque females are one such species, exhibiting cyclical facial color variation that indicates ovulatory status, but in which the function of interindividual variation is unknown. We collected digital images of the faces of 32 rhesus macaque adult females. We assessed mating rates, and consortship by males, according to female face coloration. We also assessed whether female coloration was linked to physical (skinfold fat, body mass index) or physiological (fecal glucocorticoid metabolite [fGCM], urinary C-peptide concentrations) condition. We found that redder-faced females were mated more frequently, and consorted for longer periods by top-ranked males. Redder females had higher fGCM concentrations, perhaps related to their increased mating activity and consequent energy mobilization, and blood flow. Prior analyses have shown that female facial redness is a heritable trait, and that redder-faced females have higher annual fecundity, while other evidence suggests that color expression is likely to be a signal rather than a cue. Collectively, the available evidence suggests that female coloration has evolved at least in part via male mate choice. Its evolution as a sexually selected ornament attractive to males is probably attributable to the high female reproductive synchrony found in this species.
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Affiliation(s)
- James P Higham
- Center for the Study of Human Origins, Department of Anthropology, New York University, New York, NY, USA
- New York Consortium in Evolutionary Primatology, New York, NY, USA
| | - Clare M Kimock
- Center for the Study of Human Origins, Department of Anthropology, New York University, New York, NY, USA
- New York Consortium in Evolutionary Primatology, New York, NY, USA
| | - Tara M Mandalaywala
- Department of Psychological and Brain Sciences, 135 Hicks Way/Tobin Hall, University of Massachusetts Amherst, Amherst, MA, USA
| | - Michael Heistermann
- Endocrinology Laboratory, German Primate Research Center (DPZ), Kellnerweg, Göttingen, Germany
| | - Julie Cascio
- Center for the Study of Human Origins, Department of Anthropology, New York University, New York, NY, USA
- New York Consortium in Evolutionary Primatology, New York, NY, USA
| | - Megan Petersdorf
- Center for the Study of Human Origins, Department of Anthropology, New York University, New York, NY, USA
- New York Consortium in Evolutionary Primatology, New York, NY, USA
| | - Sandra Winters
- Center for the Study of Human Origins, Department of Anthropology, New York University, New York, NY, USA
- New York Consortium in Evolutionary Primatology, New York, NY, USA
| | - William L Allen
- Center for the Study of Human Origins, Department of Anthropology, New York University, New York, NY, USA
- New York Consortium in Evolutionary Primatology, New York, NY, USA
| | - Constance Dubuc
- Center for the Study of Human Origins, Department of Anthropology, New York University, New York, NY, USA
- New York Consortium in Evolutionary Primatology, New York, NY, USA
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18
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Photoperiodic regulation of dopamine signaling regulates seasonal changes in retinal photosensitivity in mice. Sci Rep 2021; 11:1843. [PMID: 33469071 PMCID: PMC7815869 DOI: 10.1038/s41598-021-81540-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 01/08/2021] [Indexed: 12/28/2022] Open
Abstract
At high latitudes, approximately 10% of people suffer from depression during the winter season, a phenomenon known as seasonal affective disorder (SAD). Shortened photoperiod and/or light intensity during winter season are risk factors for SAD, and bright light therapy is an effective treatment. Interestingly, reduced retinal photosensitivity along with the mood is observed in SAD patients in winter. However, the molecular basis underlying seasonal changes in retinal photosensitivity remains unclear, and pharmacological intervention is required. Here we show photoperiodic regulation of dopamine signaling and improvement of short day–attenuated photosensitivity by its pharmacological intervention in mice. Electroretinograms revealed dynamic seasonal changes in retinal photosensitivity. Transcriptome analysis identified short day-mediated suppression of the Th gene, which encodes tyrosine hydroxylase, a rate-limiting enzyme for dopamine biosynthesis. Furthermore, pharmacological intervention in dopamine signaling through activation of the cAMP signaling pathway rescued short day–attenuated photosensitivity, whereas dopamine receptor antagonists decreased photosensitivity under long-day conditions. Our results reveal molecular basis of seasonal changes in retinal photosensitivity in mammals. In addition, our findings provide important insights into the pathogenesis of SAD and offer potential therapeutic interventions.
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19
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McBrayer LD, Orton RW, Kinsey CT, Neel LK. Conservation and Management Strategies Create Opportunities for Integrative Organismal Research. Integr Comp Biol 2020; 60:509-521. [PMID: 32531064 DOI: 10.1093/icb/icaa069] [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
Conservation and management activities are geared toward the achievement of particular goals for a specific species, or groups of species, at the population level or higher. Conversely, organismal or functional research is typically organized by hypothesis tests or descriptive work that examines a broader theory studying individual organismal traits. Here, we outline how integrative organismal biologists might conduct mutually beneficial and meaningful research to inform or assist conservation and management biologists. We argue that studies of non-target species are very useful to both groups because non-target species can meet the goals of managers and organismal biologists alike, while also informing the other. We highlight our work on a threatened lizard species' thermal physiology, behavior, and color pattern-all of which are impacted by species management plans for sympatric, threatened, bird species. We show that management practices affect activity time, thermal adaptation, and substrate use, while also altering predation rates, crypsis, ectoparasite load, and sexual coloration in the study species. These case studies exemplify the challenges of conservation and management efforts for threatened or endangered species in that non-target species can be both positively and negatively affected by those efforts. Yet, the collaboration of organismal biologists with conservation and management efforts provides a productive system for mutually informative research.
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Affiliation(s)
- Lance D McBrayer
- Department of Biology, Georgia Southern University, Statesboro, GA 30460, USA
| | - Richard W Orton
- Department of Biology, University of Texas at Arlington, 337 Life Science Building, Arlington, TX 76019, USA
| | - Chase T Kinsey
- Department of Biological Sciences, 132 Long Hall, Clemson University, Clemson, SC 29634, USA
| | - Lauren K Neel
- School of Life Sciences, Arizona State University, Tempe, AZ 85281, USA
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20
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Wilson VAD, Kade C, Moeller S, Treue S, Kagan I, Fischer J. Macaque Gaze Responses to the Primatar: A Virtual Macaque Head for Social Cognition Research. Front Psychol 2020; 11:1645. [PMID: 32765373 PMCID: PMC7379899 DOI: 10.3389/fpsyg.2020.01645] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 06/17/2020] [Indexed: 12/31/2022] Open
Abstract
Following the expanding use and applications of virtual reality in everyday life, realistic virtual stimuli are of increasing interest in cognitive studies. They allow for control of features such as gaze, expression, appearance, and movement, which may help to overcome limitations of using photographs or video recordings to study social responses. In using virtual stimuli however, one must be careful to avoid the uncanny valley effect, where realistic stimuli can be perceived as eerie, and induce an aversion response. At the same time, it is important to establish whether responses to virtual stimuli mirror responses to depictions of a real conspecific. In the current study, we describe the development of a new virtual monkey head with realistic facial features for experiments with nonhuman primates, the "Primatar." As a first step toward validation, we assessed how monkeys respond to facial images of a prototype of this Primatar compared to images of real monkeys (RMs), and an unrealistic model. We also compared gaze responses between original images and scrambled as well as obfuscated versions of these images. We measured looking time to images in six freely moving long-tailed macaques (Macaca fascicularis) and gaze exploration behavior in three rhesus macaques (Macaca mulatta). Both groups showed more signs of overt attention to original images than scrambled or obfuscated images. In addition, we found no evidence for an uncanny valley effect; since for both groups, looking times did not differ between real, realistic, or unrealistic images. These results provide important data for further development of our Primatar for use in social cognition studies and more generally for cognitive research with virtual stimuli in nonhuman primates. Future research on the absence of an uncanny valley effect in macaques is needed, to elucidate the roots of this mechanism in humans.
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Affiliation(s)
- Vanessa A. D. Wilson
- Department of Primate Cognition, Johann-Friedrich-Blumenbach Institute for Zoology and Anthropology, University of Göttingen, Göttingen, Germany
- Cognitive Ethology Laboratory, German Primate Center – Leibniz Institute for Primate Research, Göttingen, Germany
- Leibniz-ScienceCampus Primate Cognition, Göttingen, Germany
| | - Carolin Kade
- Cognitive Ethology Laboratory, German Primate Center – Leibniz Institute for Primate Research, Göttingen, Germany
| | - Sebastian Moeller
- Leibniz-ScienceCampus Primate Cognition, Göttingen, Germany
- Georg-Elias-Müller Institute of Psychology, University of Göttingen, Göttingen, Germany
- Cognitive Neuroscience Laboratory, German Primate Center – Leibniz Institute for Primate Research, Göttingen, Germany
| | - Stefan Treue
- Leibniz-ScienceCampus Primate Cognition, Göttingen, Germany
- Georg-Elias-Müller Institute of Psychology, University of Göttingen, Göttingen, Germany
- Cognitive Neuroscience Laboratory, German Primate Center – Leibniz Institute for Primate Research, Göttingen, Germany
- Bernstein Center for Computational Neuroscience, Göttingen, Germany
| | - Igor Kagan
- Leibniz-ScienceCampus Primate Cognition, Göttingen, Germany
- Cognitive Neuroscience Laboratory, German Primate Center – Leibniz Institute for Primate Research, Göttingen, Germany
| | - Julia Fischer
- Department of Primate Cognition, Johann-Friedrich-Blumenbach Institute for Zoology and Anthropology, University of Göttingen, Göttingen, Germany
- Cognitive Ethology Laboratory, German Primate Center – Leibniz Institute for Primate Research, Göttingen, Germany
- Leibniz-ScienceCampus Primate Cognition, Göttingen, Germany
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21
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The Role of Sexual Selection in the Evolution of Facial Displays in Male Non-human Primates and Men. ADAPTIVE HUMAN BEHAVIOR AND PHYSIOLOGY 2020. [DOI: 10.1007/s40750-020-00139-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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22
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Tuljapurkar S, Zuo W, Coulson T, Horvitz C, Gaillard J. Skewed distributions of lifetime reproductive success: beyond mean and variance. Ecol Lett 2020; 23:748-756. [DOI: 10.1111/ele.13467] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 12/17/2019] [Accepted: 01/02/2020] [Indexed: 12/11/2022]
Affiliation(s)
| | - Wenyun Zuo
- Department of Biology Stanford University Stanford CA 94305‐5020 USA
| | - Tim Coulson
- Department of Zoology University of Oxford Oxford OX1 3SZ UK
| | - Carol Horvitz
- Department of Biology University of Miami Coral Gables FL 33124‐0421 USA
| | - Jean‐Michel Gaillard
- Laboratoire de Biométrie et Biologie Evolutive CNRS, UMR 5558 Université Lyon 1 F‐69622 Villeurbanne France
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23
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Caro T, Mallarino R. Coloration in Mammals. Trends Ecol Evol 2020; 35:357-366. [PMID: 31980234 PMCID: PMC10754262 DOI: 10.1016/j.tree.2019.12.008] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Revised: 12/16/2019] [Accepted: 12/17/2019] [Indexed: 12/11/2022]
Abstract
Mammalian colors and color patterns are some of the most diverse and conspicuous traits found in nature and have been widely studied from genetic/developmental and evolutionary perspectives. In this review we first discuss the proximate causes underlying variation in pigment type (i.e., color) and pigment distribution (i.e., color pattern) and highlight both processes as having a distinct developmental basis. Then, using multiple examples, we discuss ultimate factors that have driven the evolution of coloration differences in mammals, which include background matching, intra- and interspecific signaling, and physiological influences. Throughout, we outline bridges between developmental and functional investigatory approaches that help broaden knowledge of mammals' memorable external appearances, and we point out areas for future interdisciplinary research.
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Affiliation(s)
- Tim Caro
- School of Biological Sciences, University of Bristol, 24 Tyndall Avenue, Bristol BS81TQ, UK; Center for Population Biology, 1 Shields Avenue, University of California, Davis, CA 95616, USA.
| | - Ricardo Mallarino
- Department of Molecular Biology, Princeton University, 119 Lewis Thomas Laboratory, Washington Road, Princeton, NJ 08544, USA
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24
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Wiens JJ, Tuschhoff E. Songs versus colours versus horns: what explains the diversity of sexually selected traits? Biol Rev Camb Philos Soc 2020; 95:847-864. [PMID: 32092241 DOI: 10.1111/brv.12593] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Revised: 01/25/2020] [Accepted: 02/10/2020] [Indexed: 01/14/2023]
Abstract
Papers on sexual selection often highlight the incredible diversity of sexually selected traits across animals. Yet, few studies have tried to explain why this diversity evolved. Animals use many different types of traits to attract mates and outcompete rivals, including colours, songs, and horns, but it remains unclear why, for example, some taxa have songs, others have colours, and others horns. Here, we first conduct a systematic survey of the basic diversity and distribution of different types of sexually selected signals and weapons across the animal Tree of Life. Based on this survey, we describe seven major patterns in trait diversity and distributions. We then discuss 10 unanswered questions raised by these patterns, and how they might be addressed. One major pattern is that most types of sexually selected signals and weapons are apparently absent from most animal phyla (88%), in contrast to the conventional wisdom that a diversity of sexually selected traits is present across animals. Furthermore, most trait diversity is clustered in Arthropoda and Chordata, but only within certain clades. Within these clades, many different types of traits have evolved, and many types appear to have evolved repeatedly. By contrast, other major arthropod and chordate clades appear to lack all or most trait types, and similar patterns are repeated at smaller phylogenetic scales (e.g. within insects). Although most research on sexual selection focuses on female choice, we find similar numbers of traits (among sampled species) are involved in male contests (44%) and female choice (55%). Overall, these patterns are largely unexplained and unexplored, as are many other fundamental questions about the evolution of these traits. We suggest that understanding the diversity of sexually selected traits may require a shift towards macroevolutionary studies at relatively deep timescales (e.g. tens to hundreds of millions of years ago).
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Affiliation(s)
- John J Wiens
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, 85721-0088, U.S.A
| | - E Tuschhoff
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, 85721-0088, U.S.A
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25
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Winters S, Allen WL, Higham JP. The structure of species discrimination signals across a primate radiation. eLife 2020; 9:47428. [PMID: 31928629 PMCID: PMC6957270 DOI: 10.7554/elife.47428] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 11/29/2019] [Indexed: 12/13/2022] Open
Abstract
Discriminating conspecifics from heterospecifics can help avoid costly interactions between closely related sympatric species. The guenons, a recent primate radiation, exhibit high degrees of sympatry and form multi-species groups. Guenons have species-specific colorful face patterns hypothesized to function in species discrimination. Here, we use a machine learning approach to identify face regions most essential for species classification across fifteen guenon species. We validate these computational results using experiments with live guenons, showing that facial traits critical for accurate classification influence selective attention toward con- and heterospecific faces. Our results suggest variability among guenon species in reliance on single-trait-based versus holistic facial characteristics for species discrimination, with behavioral responses and computational results indicating variation from single-trait to whole-face patterns. Our study supports a role for guenon face patterns in species discrimination, and shows how complex signals can be informative about differences between species across a speciose and highly sympatric radiation.
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Affiliation(s)
- Sandra Winters
- Department of Anthropology, New York University, New York, United States.,New York Consortium in Evolutionary Primatology, New York, United States
| | - William L Allen
- Department of Anthropology, New York University, New York, United States.,New York Consortium in Evolutionary Primatology, New York, United States.,Department of Biosciences, Swansea University, Wales, United Kingdom
| | - James P Higham
- Department of Anthropology, New York University, New York, United States.,New York Consortium in Evolutionary Primatology, New York, United States
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26
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Male characteristics as predictors of genital color and display variation in vervet monkeys. Behav Ecol Sociobiol 2020. [DOI: 10.1007/s00265-019-2787-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Abstract
In the animal kingdom, conspicuous colors are often used for inter- and intra-sexual communication. Even though primates are the most colorful mammalian taxon, many questions, including what potential information color signals communicate to social partners, are not fully understood. Vervet monkeys (Chlorocebus pygerythrus) are ideal to examine the covariates of color signals. Males have multi-colored genitals, which they present during distinctive male-male interactions, known as the “Red-White-and-Blue” (RWB) display, but the genitals are also visible across a variety of other contexts, and it is unclear what this color display signals to recipients. We recorded genital color presentations and standardized digital photos of male genitals (N = 405 photos) over one mating season for 20 adult males in three groups at the Samara Private Game Reserve, South Africa. We combined these with data on male characteristics (dominance, age, tenure length, injuries, and fecal glucocorticoid metabolite concentrations). Using visual modeling methods, we measured single colors (red, white, blue) but also the contrasts between colors. We assessed the frequency of the RWB genital display and male variation in genital coloration and linked this to male characteristics. Our data suggest that the number of genital displays increased with male dominance. However, none of the variables investigated explained the inter- and intra-individual variation in male genital coloration. These results suggest that the frequency of the RWB genital display, but not its color value, is related to dominance, providing valuable insights on covariation in color signals and their display in primates.
Significance statement
Conspicuous colors in animals often communicate individual quality to mates and rivals. By investigating vervet monkeys, a primate species in which males present their colorful genitals within several behavioral displays, we aim to identify the covariates of such colorful signals and their behavioral display. Using visual modeling methods for the color analysis and combining behavioral display data and color data with male characteristics, we found that high-ranking males displayed their colorful genitals more frequently than lower-ranking ones. In contrast, color variation was not influenced by male dominance, age, tenure length, or health. Our results can serve as a basis for future investigations on the function of colorful signals and behavioral displays, such as a badge of status or mate choice in primates.
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27
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Kimock CM, Dubuc C, Brent LJN, Higham JP. Male morphological traits are heritable but do not predict reproductive success in a sexually-dimorphic primate. Sci Rep 2019; 9:19794. [PMID: 31874959 PMCID: PMC6930303 DOI: 10.1038/s41598-019-52633-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Accepted: 10/18/2019] [Indexed: 11/25/2022] Open
Abstract
Sexual selection favours traits that increase reproductive success via increased competitive ability, attractiveness, or both. Male rhesus macaque (Macaca mulatta) morphological traits are likely to reflect the effects of multiple sexual selection pressures. Here, we use a quantitative genetic approach to investigate the production and maintenance of variation in male rhesus macaque morphometric traits which may be subject to sexual selection. We collected measurements of body size, canine length, and fat, from 125 male and 21 female free-ranging rhesus macaques on Cayo Santiago. We also collected testis volumes from males. We used a genetic pedigree to calculate trait heritability, to investigate potential trait trade-offs, and to estimate selection gradients. We found that variation in most male morphometric traits was heritable, but found no evidence of trait trade-offs nor that traits predicted reproductive success. Our results suggest that male rhesus macaque morphometric traits are either not under selection, or are under mechanisms of sexual selection that we could not test (e.g. balancing selection). In species subject to complex interacting mechanisms of selection, measures of body size, weaponry, and testis volume may not increase reproductive success via easily-testable mechanisms such as linear directional selection.
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Affiliation(s)
- Clare M Kimock
- Center for the Study of Human Origins, Department of Anthropology, New York University, New York, NY, USA.
| | - Constance Dubuc
- Center for the Study of Human Origins, Department of Anthropology, New York University, New York, NY, USA
| | - Lauren J N Brent
- Center for Research in Animal Behaviour, University of Exeter, Exeter, UK
| | - James P Higham
- Center for the Study of Human Origins, Department of Anthropology, New York University, New York, NY, USA
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28
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Altschul DM, Robinson LM, Coleman K, Capitanio JP, Wilson VAD. An Exploration of the Relationships Among Facial Dimensions, Age, Sex, Dominance Status, and Personality in Rhesus Macaques ( Macaca mulatta). INT J PRIMATOL 2019; 40:532-552. [PMID: 32747846 PMCID: PMC7398590 DOI: 10.1007/s10764-019-00104-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 07/08/2019] [Indexed: 01/12/2023]
Abstract
Aspects of personality in nonhuman primates have been linked to health, social relationships, and life history outcomes. In humans as well as nonhuman primates, facial morphology is associated with assertiveness, aggression, and measures of dominance status. In this study we aimed to examine the relationship among facial morphology, age, sex, dominance status, and ratings on the personality dimensions Confidence, Openness, Assertiveness, Friendliness, Activity, and Anxiety in rhesus macaques (Macaca mulatta). We measured facial width-to-height ratio (fWHR) and lower-height/full-height ratio (fLHFH) using photographs from 109 captive rhesus macaques, which observers also assessed for dominance status and personality, and explored the associations among facial morphology, age, sex, dominance status, and personality. fWHR and fLHFH personality associations depended on age category: Assertiveness was associated with higher fWHR and fLHFH, and Confidence was associated with lower fWHR and fLHFH, but all these associations were consistent only in individuals <8 yr. of age. We found fWHR and fLHFH to not be consistently associated with sex or dominance status; compared to younger individuals, we found few associations with fWHR and fLHFH for individuals older than 8 yr., which may be due to limited sample size. Our results indicate that in macaques <8 yr. old, facial morphology is associated with the Assertiveness and Confidence personality dimensions, which is consistent with results suggesting a relationship between fWHR and trait aggression in humans and assertiveness in brown capuchins, all of which implies that fWHR might be a cue to assertive and aggressive traits.
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Affiliation(s)
- D. M. Altschul
- Department of Psychology, University of Edinburgh, Edinburgh, UK
- Scottish Primate Research Group, Edinburgh EH89JZ, UK
| | - L. M. Robinson
- Domestication Lab, Konrad Lorenz Institute of Ethology, University of Veterinary Medicine Vienna, A-1160 Vienna, Austria
- Language Research Center, Georgia State University, Atlanta, GA 30034, USA
| | - K. Coleman
- Oregon National Primate Research Center, Department of Comparative Medicine, Oregon Health & Science University, Portland, OR, USA
| | - J. P. Capitanio
- Department of Psychology, University of California, Davis, CA, USA
- California National Primate Research Center, Davis, CA, USA
| | - V. A. D. Wilson
- Johann-Friedrich-Blumenbach Institute for Zoology and Anthropology, University of Göttingen, Göttingen, Germany
- Cognitive Ethology, German Primate Center, Göttingen, Germany
- Leibniz Science Campus Primate Cognition, Göttingen, Germany
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29
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Moreira LAA, Duytschaever G, Higham JP, Melin AD. Platyrrhine color signals: New horizons to pursue. Evol Anthropol 2019; 28:236-248. [PMID: 31609040 PMCID: PMC6865018 DOI: 10.1002/evan.21798] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 06/17/2019] [Accepted: 08/07/2019] [Indexed: 01/26/2023]
Abstract
Like catarrhines, some platyrrhines show exposed and reddish skin, raising the possibility that reddish signals have evolved convergently. This variation in skin exposure and color combined with sex-linked polymorphic color vision in platyrrhines presents a unique, and yet underexplored, opportunity to investigate the relative importance of chromatic versus achromatic signals, the influence of color perception on signal evolution, and to understand primate communication broadly. By coding the facial skin exposure and color of 96 platyrrhines, 28 catarrhines, 7 strepsirrhines, 1 tarsiiform, and 13 nonprimates, and by simulating the ancestral character states for these traits, we provide the first analysis of the distribution and evolution of facial skin exposure and color in platyrrhini. We highlight ways in which studying the presence and use of color signals by platyrrhines and other primates will enhance our understanding of the evolution of color signals, and the forces shaping color vision.
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Affiliation(s)
- Laís A. A. Moreira
- Department of Anthropology & ArchaeologyUniversity of CalgaryCalgaryAlbertaCanada
| | - Gwen Duytschaever
- Department of Anthropology & ArchaeologyUniversity of CalgaryCalgaryAlbertaCanada
| | | | - Amanda D. Melin
- Department of Anthropology & ArchaeologyUniversity of CalgaryCalgaryAlbertaCanada
- Department of Medical GeneticsUniversity of CalgaryCalgaryAlbertaCanada
- Alberta Children's Hospital Research InstituteCalgaryAlbertaCanada
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Murphy AP, Leopold DA. A parameterized digital 3D model of the Rhesus macaque face for investigating the visual processing of social cues. J Neurosci Methods 2019; 324:108309. [PMID: 31229584 PMCID: PMC7446874 DOI: 10.1016/j.jneumeth.2019.06.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 05/31/2019] [Accepted: 06/01/2019] [Indexed: 12/22/2022]
Abstract
BACKGROUND Rhesus macaques are the most popular model species for studying the neural basis of visual face processing and social interaction using intracranial methods. However, the challenge of creating realistic, dynamic, and parametric macaque face stimuli has limited the experimental control and ethological validity of existing approaches. NEW METHOD We performed statistical analyses of in vivo computed tomography data to generate an anatomically accurate, three-dimensional representation of Rhesus macaque cranio-facial morphology. The surface structures were further edited, rigged and textured by a professional digital artist with careful reference to photographs of macaque facial expression, colouration and pelage. RESULTS The model offers precise, continuous, parametric control of craniofacial shape, emotional expression, head orientation, eye gaze direction, and many other parameters that can be adjusted to render either static or dynamic high-resolution faces. Example single-unit responses to such stimuli in macaque inferotemporal cortex demonstrate the value of parametric control over facial appearance and behaviours. COMPARISON WITH EXISTING METHOD(S) The generation of such a high-dimensionality and systematically controlled stimulus set of conspecific faces, with accurate craniofacial modelling and professional finalization of facial details, is currently not achievable using existing methods. CONCLUSIONS The results herald a new set of possibilities in adaptive sampling of a high-dimensional and socially meaningful feature space, thus opening the door to systematic testing of hypotheses about the abundant neural specialization for faces found in the primate.
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Affiliation(s)
- Aidan P Murphy
- Section on Cognitive Neurophysiology and Imaging, NIMH, Bethesda, MD, USA.
| | - David A Leopold
- Section on Cognitive Neurophysiology and Imaging, NIMH, Bethesda, MD, USA
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31
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The redder the better? Information content of red skin coloration in female Japanese macaques. Behav Ecol Sociobiol 2019. [DOI: 10.1007/s00265-019-2712-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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32
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Lüpold S, Simmons LW, Grueter CC. Sexual ornaments but not weapons trade off against testes size in primates. Proc Biol Sci 2019; 286:20182542. [PMID: 30966988 PMCID: PMC6501695 DOI: 10.1098/rspb.2018.2542] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 03/18/2019] [Indexed: 12/27/2022] Open
Abstract
Males must partition their limited reproductive investments between traits that promote access to females (sexual ornaments and weapons) and traits that enhance fertilization success, such as testes and ejaculates. Recent studies show that if the most weaponized males can monopolize access to females through contest competition, thereby reducing the risk of sperm competition, they tend to invest less in sperm production. However, how males invest in sexual ornaments relative to sperm production remains less clear. If male ornaments serve as badges of status, with high-ranking males attaining near-exclusive access to females, similar to monopolizing females through combat, their expression should also covary negatively with investment in post-mating traits. In a comparative study across primates, which exhibit considerable diversification in sexual ornamentation, male weaponry and testes size, we found relative testes size to decrease with sexual ornaments but increase with canine size. These contrasting evolutionary trajectories might be driven by differential selection, functional constraints or temporal patterns of metabolic investment between the different types of sexual traits. Importantly, however, our results indicate that the theory of relative investments between weapons and testes in the context of monopolizing females can extend to male ornaments.
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Affiliation(s)
- Stefan Lüpold
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, 8057 Zurich, Switzerland
| | - Leigh W. Simmons
- Centre for Evolutionary Biology, School of Biological Sciences (M092), The University of Western Australia, Crawley, Western Australia 6009, Australia
| | - Cyril C. Grueter
- Centre for Evolutionary Biology, School of Biological Sciences (M092), The University of Western Australia, Crawley, Western Australia 6009, Australia
- School of Human Sciences (M309), The University of Western Australia, Crawley, Western Australia 6009, Australia
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Rosenfield KA, Semple S, Georgiev AV, Maestripieri D, Higham JP, Dubuc C. Experimental evidence that female rhesus macaques ( Macaca mulatta) perceive variation in male facial masculinity. ROYAL SOCIETY OPEN SCIENCE 2019; 6:181415. [PMID: 30800385 PMCID: PMC6366174 DOI: 10.1098/rsos.181415] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 12/17/2018] [Indexed: 06/09/2023]
Abstract
Among many primate species, face shape is sexually dimorphic, and male facial masculinity has been proposed to influence female mate choice and male-male competition by signalling competitive ability. However, whether conspecifics pay attention to facial masculinity has only been assessed in humans. In a study of free-ranging rhesus macaques, Macaca mulatta, we used a two-alternative look-time experiment to test whether females perceive male facial masculinity. We presented 107 females with pairs of images of male faces-one with a more masculine shape and one more feminine-and recorded their looking behaviour. Females looked at the masculine face longer than at the feminine face in more trials than predicted by chance. Although there was no overall difference in average look-time between masculine and feminine faces across all trials, females looked significantly longer at masculine faces in a subset of trials for which the within-pair difference in masculinity was most pronounced. Additionally, the proportion of time subjects looked toward the masculine face increased as the within-pair difference in masculinity increased. This study provides evidence that female macaques perceive variation in male facial shape, a necessary condition for intersexual selection to operate on such a trait. It also highlights the potential impact of perceptual thresholds on look-time experiments.
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Affiliation(s)
- Kevin A. Rosenfield
- Centre for Research in Evolutionary, Social and Interdisciplinary Anthropology, University of Roehampton, Holybourne Avenue, London SW15 4JD, UK
- Department of Anthropology, Pennsylvania State University, 409 Carpenter Building, University Park, PA 16802, USA
| | - Stuart Semple
- Centre for Research in Evolutionary, Social and Interdisciplinary Anthropology, University of Roehampton, Holybourne Avenue, London SW15 4JD, UK
| | - Alexander V. Georgiev
- School of Natural Sciences, Bangor University, Bangor, Gwynedd LL57 2UW, UK
- Institute for Mind and Biology, The University of Chicago, 940 East 57th Street, Chicago, IL 60637, USA
| | - Dario Maestripieri
- Institute for Mind and Biology, The University of Chicago, 940 East 57th Street, Chicago, IL 60637, USA
| | - James P. Higham
- Department of Anthropology, New York University, 25 Waverly Place, New York, NY 10003, USA
| | - Constance Dubuc
- Department of Anthropology, New York University, 25 Waverly Place, New York, NY 10003, USA
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
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Hiramatsu C, Melin AD, Allen WL, Dubuc C, Higham JP. Experimental evidence that primate trichromacy is well suited for detecting primate social colour signals. Proc Biol Sci 2018; 284:rspb.2016.2458. [PMID: 28615496 PMCID: PMC5474062 DOI: 10.1098/rspb.2016.2458] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 05/17/2017] [Indexed: 12/14/2022] Open
Abstract
Primate trichromatic colour vision has been hypothesized to be well tuned for detecting variation in facial coloration, which could be due to selection on either signal wavelengths or the sensitivities of the photoreceptors themselves. We provide one of the first empirical tests of this idea by asking whether, when compared with other visual systems, the information obtained through primate trichromatic vision confers an improved ability to detect the changes in facial colour that female macaque monkeys exhibit when they are proceptive. We presented pairs of digital images of faces of the same monkey to human observers and asked them to select the proceptive face. We tested images that simulated what would be seen by common catarrhine trichromatic vision, two additional trichromatic conditions and three dichromatic conditions. Performance under conditions of common catarrhine trichromacy, and trichromacy with narrowly separated LM cone pigments (common in female platyrrhines), was better than for evenly spaced trichromacy or for any of the dichromatic conditions. These results suggest that primate trichromatic colour vision confers excellent ability to detect meaningful variation in primate face colour. This is consistent with the hypothesis that social information detection has acted on either primate signal spectral reflectance or photoreceptor spectral tuning, or both.
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Affiliation(s)
- Chihiro Hiramatsu
- Department of Human Science, Faculty of Design, Kyushu University, 4-9-1 Shiobaru, Minamiku, Fukuoka 815-8540, Japan .,Physiological Anthropology Research Center, Kyushu University, 4-9-1 Shiobaru, Minamiku, Fukuoka 815-8540, Japan
| | - Amanda D Melin
- Department of Anthropology and Archaeology, University of Calgary, Calgary, Alberta, Canada.,Department of Medical Genetics, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - William L Allen
- Department of Anthropology, New York University, New York, NY, USA.,Department of Biosciences, Swansea University, Swansea, UK
| | - Constance Dubuc
- Department of Anthropology, New York University, New York, NY, USA.,Department of Zoology, University of Cambridge, Cambridge, UK
| | - James P Higham
- Department of Anthropology, New York University, New York, NY, USA
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Petersdorf M, Dubuc C, Georgiev AV, Winters S, Higham JP. Is male rhesus macaque facial coloration under intrasexual selection? Behav Ecol 2017; 28:1472-1481. [PMID: 29622929 PMCID: PMC5872909 DOI: 10.1093/beheco/arx110] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 07/10/2017] [Accepted: 07/27/2017] [Indexed: 12/24/2022] Open
Abstract
Exaggerated male traits can evolve under intra- or intersexual selection, but it remains less clear how often both mechanisms act together on trait evolution. While the males of many anthropoid primate species exhibit colorful signals that appear to be badges of status under intrasexual selection, the red facial coloration of male rhesus macaques (Macaca mulatta) appears to have evolved primarily under intersexual selection and female mate choice. Nonetheless, experiments show that red color is salient to males, raising the question of whether the signal may also be under intrasexual selection. Here, we examine whether males express this signal more strongly in competitive contexts. Facial images were collected on all 15 adult males of a free-ranging social group during the peak of the mating season, and coloration was quantified using visual models. Results show that males more similar in facial redness were more likely to interact aggressively than more dissimilar ones, suggesting that color may be involved in the assessment of rivals. Furthermore, males exhibited darker coloration on days they were observed copulating, and dominance rank predicted facial redness only on copulating days, suggesting that coloration may also advertise motivation to defend a mate. Male rhesus macaque facial coloration may thus mediate agonistic interactions with rivals during competition over reproductive opportunities, such that it is under both inter- and intrasexual selection. However, color differences were small, raising perceptibility questions. It remains possible that color variation reflects differences in male condition, which in turn alter investment towards male-male competition and mating effort.
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Affiliation(s)
- Megan Petersdorf
- Department of Anthropology, New York University, 25 Waverly Pl, New York,
NY 10003, USA
| | - Constance Dubuc
- Department of Anthropology, New York University, 25 Waverly Pl, New York,
NY 10003, USA
| | - Alexander V Georgiev
- Institute for Mind and Biology, The University of Chicago, 940 E 57th St,
Chicago, IL 60637, USA
- School of Biological Sciences, Bangor University, Deiniol Road, Bangor,
Gwynedd LL57 2UW, UK
| | - Sandra Winters
- Department of Anthropology, New York University, 25 Waverly Pl, New York,
NY 10003, USA
| | - James P Higham
- Department of Anthropology, New York University, 25 Waverly Pl, New York,
NY 10003, USA
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36
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Batabyal A, Thaker M. Signalling with physiological colours: high contrast for courtship but speed for competition. Anim Behav 2017. [DOI: 10.1016/j.anbehav.2017.05.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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37
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Muller MN. Testosterone and reproductive effort in male primates. Horm Behav 2017; 91:36-51. [PMID: 27616559 PMCID: PMC5342957 DOI: 10.1016/j.yhbeh.2016.09.001] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 09/06/2016] [Accepted: 09/07/2016] [Indexed: 10/21/2022]
Abstract
Considerable evidence suggests that the steroid hormone testosterone mediates major life-history trade-offs in vertebrates, promoting mating effort at the expense of parenting effort or survival. Observations from a range of wild primates support the "Challenge Hypothesis," which posits that variation in male testosterone is more closely associated with aggressive mating competition than with reproductive physiology. In both seasonally and non-seasonally breeding species, males increase testosterone production primarily when competing for fecund females. In species where males compete to maintain long-term access to females, testosterone increases when males are threatened with losing access to females, rather than during mating periods. And when male status is linked to mating success, and dependent on aggression, high-ranking males normally maintain higher testosterone levels than subordinates, particularly when dominance hierarchies are unstable. Trade-offs between parenting effort and mating effort appear to be weak in most primates, because direct investment in the form of infant transport and provisioning is rare. Instead, infant protection is the primary form of paternal investment in the order. Testosterone does not inhibit this form of investment, which relies on male aggression. Testosterone has a wide range of effects in primates that plausibly function to support male competitive behavior. These include psychological effects related to dominance striving, analgesic effects, and effects on the development and maintenance of the armaments and adornments that males employ in mating competition.
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Affiliation(s)
- Martin N Muller
- Department of Anthropology, University of New Mexico, United States.
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38
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Melin AD, Khetpal V, Matsushita Y, Zhou K, Campos FA, Welker B, Kawamura S. Howler monkey foraging ecology suggests convergent evolution of routine trichromacy as an adaptation for folivory. Ecol Evol 2017; 7:1421-1434. [PMID: 28261454 PMCID: PMC5330884 DOI: 10.1002/ece3.2716] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Revised: 11/28/2016] [Accepted: 12/18/2016] [Indexed: 02/03/2023] Open
Abstract
Primates possess remarkably variable color vision, and the ecological and social factors shaping this variation remain heavily debated. Here, we test whether central tenants of the folivory hypothesis of routine trichromacy hold for the foraging ecology of howler monkeys. Howler monkeys (genus Alouatta) and paleotropical primates (Parvorder: Catarrhini) have independently acquired routine trichromacy through fixation of distinct mid- to long-wavelength-sensitive (M/LWS) opsin genes on the X-chromosome. The presence of routine trichromacy in howlers, while other diurnal neotropical monkeys (Platyrrhini) possess polymorphic trichromacy, is poorly understood. A selective force proposed to explain the evolution of routine trichromacy in catarrhines-reliance on young, red leaves-has received scant attention in howlers, a gap we fill in this study. We recorded diet, sequenced M/LWS opsin genes in four social groups of Alouatta palliata, and conducted colorimetric analysis of leaves consumed in Sector Santa Rosa, Costa Rica. For a majority of food species, including Ficus trees, an important resource year-round, young leaves were more chromatically conspicuous from mature leaves to trichromatic than to hypothetical dichromatic phenotypes. We found that 18% of opsin genes were MWS/LWS hybrids; when combined with previous research, the incidence of hybrid M/LWS opsins in this species is 13%. In visual models of food discrimination ability, the hybrid trichromatic phenotype performed slightly poorer than normal trichromacy, but substantially better than dichromacy. Our results provide support for the folivory hypothesis of routine trichromacy. Similar ecological pressures, that is, the search for young, reddish leaves, may have driven the independent evolution of routine trichromacy in primates on separate continents. We discuss our results in the context of balancing selection acting on New World monkey opsin genes and hypothesize that howlers experience stronger selection against dichromatic phenotypes than other sympatric species, which rely more heavily on cryptic foods.
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Affiliation(s)
- Amanda D. Melin
- Department of Anthropology and ArchaeologyUniversity of CalgaryCalgaryABCanada
- Department of Medical Genetics and Alberta Children’s Hospital Research InstituteUniversity of CalgaryCalgaryABCanada
| | - Vishal Khetpal
- Department of AnthropologyWashington University in St. LouisSt. LouisMOUSA
| | - Yuka Matsushita
- Department of Integrated BiosciencesGraduate School of Frontier SciencesThe University of TokyoTokyoJapan
| | - Kaile Zhou
- Department of Integrated BiosciencesGraduate School of Frontier SciencesThe University of TokyoTokyoJapan
- Department of Plant ProtectionCollege of Agriculture and BiotechnologyZhejiang UniversityHangzhouZhejiangChina
| | - Fernando A. Campos
- Department of Anthropology and ArchaeologyUniversity of CalgaryCalgaryABCanada
- Department of AnthropologyTulane UniversityNew OrleansLAUSA
| | - Barbara Welker
- Department of AnthropologyState University of New York at GeneseoGeneseoNYUSA
| | - Shoji Kawamura
- Department of Integrated BiosciencesGraduate School of Frontier SciencesThe University of TokyoTokyoJapan
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Setchell JM. Sexual Selection and the differences between the sexes in Mandrills (Mandrillus sphinx). AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2016; 159:S105-29. [PMID: 26808101 DOI: 10.1002/ajpa.22904] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Sexual selection has become a major focus in evolutionary and behavioral ecology. It is also a popular research topic in primatology. I use studies of mandrills (Mandrillus sphinx), a classic example of extravagant armaments and ornaments in animals, to exemplify how a long-term, multidisciplinary approach that integrates field observations with laboratory methods can contribute to on-going theoretical debates in the field of sexual selection. I begin with a brief summary of the main concepts of sexual selection theory and the differences between the sexes. I then introduce mandrills and the study population and review mandrill life history, the ontogeny of sex differences, and maternal effects. Next, I focus on male-male competition and female choice, followed by the less well-studied questions of female-female competition and male choice. This review shows how different reproductive priorities lead to very different life histories and divergent adaptations in males and females. It demonstrates how broadening traditional perspectives on sexual selection beyond the ostentatious results of intense sexual selection on males leads to an understanding of more subtle and cryptic forms of competition and choice in both sexes and opens many productive avenues in the study of primate reproductive strategies. These include the potential for studies of postcopulatory selection, female intrasexual competition, and male choice. These studies of mandrills provide comparison and, I hope, inspiration for studies of both other polygynandrous species and species with mating systems less traditionally associated with sexual selection.
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Affiliation(s)
- Joanna M Setchell
- Department of Anthropology, Evolutionary Anthropology Research Group, Behaviour Ecology and Evolution Research (BEER) Centre, Durham University, Durham, DH1 3LE, UK
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40
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Testing for links between face color and age, dominance status, parity, weight, and intestinal nematode infection in a sample of female Japanese macaques. Primates 2016; 58:83-91. [DOI: 10.1007/s10329-016-0575-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2016] [Accepted: 09/07/2016] [Indexed: 11/30/2022]
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Corso J, Bowler M, Heymann EW, Roos C, Mundy NI. Highly polymorphic colour vision in a New World monkey with red facial skin, the bald uakari (Cacajao calvus). Proc Biol Sci 2016; 283:20160067. [PMID: 27053753 PMCID: PMC4843651 DOI: 10.1098/rspb.2016.0067] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 03/16/2016] [Indexed: 11/12/2022] Open
Abstract
Colour vision is highly variable in New World monkeys (NWMs). Evidence for the adaptive basis of colour vision in this group has largely centred on environmental features such as foraging benefits for differently coloured foods or predator detection, whereas selection on colour vision for sociosexual communication is an alternative hypothesis that has received little attention. The colour vision of uakaris (Cacajao) is of particular interest because these monkeys have the most dramatic red facial skin of any primate, as well as a unique fission/fusion social system and a specialist diet of seeds. Here, we investigate colour vision in a wild population of the bald uakari,C. calvus, by genotyping the X-linked opsin locus. We document the presence of a polymorphic colour vision system with an unprecedented number of functional alleles (six), including a novel allele with a predicted maximum spectral sensitivity of 555 nm. This supports the presence of strong balancing selection on different alleles at this locus. We consider different hypotheses to explain this selection. One possibility is that trichromacy functions in sexual selection, enabling females to choose high-quality males on the basis of red facial coloration. In support of this, there is some evidence that health affects facial coloration in uakaris, as well as a high prevalence of blood-borne parasitism in wild uakari populations. Alternatively, the low proportion of heterozygous female trichromats in the population may indicate selection on different dichromatic phenotypes, which might be related to cryptic food coloration. We have uncovered unexpected diversity in the last major lineage of NWMs to be assayed for colour vision, which will provide an interesting system to dissect adaptation of polymorphic trichromacy.
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Affiliation(s)
- Josmael Corso
- Programa de Pós-Graduação em Genética e Biologia Molecular, Universidade Federal do Rio Grande do Sul, Avenida Bento Gonçalves 9500, Porto Alegre, Rio Grande do Sul 91501-970, Brazil
| | - Mark Bowler
- Behavioral Ecology Division, San Diego Zoo Institute for Conservation Research, 15600 San Pasqual Valley Road, Escondido, CA 92027-7000, USA Behavioral Ecology and Sociobiology Unit, German Primate Center, Leibniz Institute for Primate Research, Kellnerweg 4, Göttingen 37077, Germany
| | - Eckhard W Heymann
- Behavioral Ecology and Sociobiology Unit, German Primate Center, Leibniz Institute for Primate Research, Kellnerweg 4, Göttingen 37077, Germany
| | - Christian Roos
- Gene Bank of Primates and Primate Genetics Laboratory, German Primate Center, Leibniz Institute for Primate Research, Kellnerweg 4, Göttingen 37077, Germany
| | - Nicholas I Mundy
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
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Grueter CC, Zhu P, Allen WL, Higham JP, Ren B, Li M. Sexually selected lip colour indicates male group-holding status in the mating season in a multi-level primate society. ROYAL SOCIETY OPEN SCIENCE 2015; 2:150490. [PMID: 27019735 PMCID: PMC4807456 DOI: 10.1098/rsos.150490] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 11/12/2015] [Indexed: 06/05/2023]
Abstract
Sexual selection typically produces ornaments in response to mate choice, and armaments in response to male-male competition. Unusually among mammals, many primates exhibit colour signals that may be related to one or both processes. Here, we document for the first time correlates of facial coloration in one of the more brightly coloured primates, the black-and-white snub-nosed monkey (Rhinopithecus bieti). Snub-nosed monkeys have a one-male unit (OMU) based social organization, but these units aggregate semi-permanently into larger bands. This form of mating system causes many males to become associated with bachelor groups. We quantified redness of the prominent lower lip in 15 males (eight bachelors, seven OMU holders) in a group at Xiangguqing, China. Using mixed models, our results show that lip redness increases with age. More interestingly, there is a significant effect of the interaction of group-holding status and mating season on redness; that is, lip colour of OMU males undergoes reddening in the mating season, whereas the lips of subadult and juvenile bachelor males become paler at that time of year. These results indicate that lip coloration is a badge of (group-holding) status during the mating season, with non-adults undergoing facial differentiation, perhaps to avoid the costs of reproductive competition. Future research should investigate whether lip coloration is a product of male-male competition, and/or female mate choice.
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Affiliation(s)
- Cyril C. Grueter
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley/Perth, Western Australia 6009, Australia
| | - Pingfen Zhu
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
| | - William L. Allen
- School of Biological, Biomedical and Environmental Sciences, University of Hull, Hull HU6 7RX, UK
| | - James P. Higham
- Center for the Study of Human Origins, Department of Anthropology, New York University, New York, NY 10003, USA
| | - Baoping Ren
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
| | - Ming Li
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
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Dubuc C, Allen WL, Cascio J, Lee DS, Maestripieri D, Petersdorf M, Winters S, Higham JP. Who cares? Experimental attention biases provide new insights into a mammalian sexual signal. Behav Ecol 2015; 27:68-74. [PMID: 29622915 DOI: 10.1093/beheco/arv117] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2015] [Revised: 06/16/2015] [Accepted: 06/19/2015] [Indexed: 11/12/2022] Open
Abstract
The effects of intrasexual and intersexual selection on male trait evolution can be difficult to disentangle, especially based on observational data. Male-male competition can limit an observer's ability to identify the effect of female mate choice independently from sexual coercion. Here, we use an experimental approach to explore whether an ornament, the red facial skin exhibited by male rhesus macaques (Macaca mulatta), might be involved in both female mate choice and male-male competition. We used a noninvasive experimental approach based on the looking time paradigm in a free-ranging setting, showing images of differently colored male faces to both adult females (N = 91) and males (N = 77), as well as to juveniles (N = 94) as a control. Results show that both adult females and males looked longer at dark red faces compared with pale pink ones. However, when considering the proportion of subjects that looked longer at dark red faces regardless of preference strength, only females showed a significant dark red bias. In contrast, juveniles did not show any preferences between stimuli, suggesting that the adult bias is not a consequence of the experimental design or related to a general sensory bias for red coloration among all age-sex classes. Collectively, these results support the role the ornament plays in female mate choice in this species and provide the first evidence that this ornament may play a role in male-male competition as well, despite a general lack of observational evidence for the latter effect to date.
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Affiliation(s)
- Constance Dubuc
- Department of Anthropology, New York University, 25 Waverly Place, New York, NY 10003, USA
| | - William L Allen
- Department of Anthropology, New York University, 25 Waverly Place, New York, NY 10003, USA
| | - Julie Cascio
- Department of Anthropology, New York University, 25 Waverly Place, New York, NY 10003, USA
| | - D Susie Lee
- Department of Anthropology, New York University, 25 Waverly Place, New York, NY 10003, USA
| | - Dario Maestripieri
- Institute for Mind and Biology, The University of Chicago, 940 East 57th Street, Chicago, IL 60637, USA, and.,Department of Comparative Human Development, The University of Chicago, 1126 East 59th Street, Chicago, IL 60637, USA
| | - Megan Petersdorf
- Department of Anthropology, New York University, 25 Waverly Place, New York, NY 10003, USA
| | - Sandra Winters
- Department of Anthropology, New York University, 25 Waverly Place, New York, NY 10003, USA
| | - James P Higham
- Department of Anthropology, New York University, 25 Waverly Place, New York, NY 10003, USA
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Mayor P, Mamani J, Montes D, González-Crespo C, Sebastián MA, Bowler M. Proximate causes of the red face of the bald uakari monkey (Cacajao calvus). ROYAL SOCIETY OPEN SCIENCE 2015; 2:150145. [PMID: 26587272 PMCID: PMC4632585 DOI: 10.1098/rsos.150145] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 06/03/2015] [Indexed: 06/05/2023]
Abstract
In social species, such as primates, facial appearances transmit a variety of social signals. Although it is suggested that the intense red colour of the face of the bald uakari monkey might be an indicator of health, this hypothesis still has not been verified. This study describes the histological structure of the skin of the face in the bald uakari, compared with other non-red neotropical primates, to better understand the maintenance of its colour. The facial skin of the bald uakari monkey is characterized by a thinner epidermis, absence of melanin pigments and a high density of vascular capillaries that spread below the epidermis. These vascular capillaries are larger and more tortuous than in other neotropical primates. The skin of the face of the bald uakari monkey allows a direct external assessment of haematological status, suggesting that the colour of the face would be an honest indicator of health, but could also signal sexual or behavioural states.
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Affiliation(s)
- P. Mayor
- Department de Sanitat i Anatomia Animals, Faculty of Veterinary, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain
- YAVACUS, Yavarí Conservación y Uso Sostenible, Iquitos, Perú
| | - J. Mamani
- Laboratory of Pathology, Faculty of Veterinary, Universidad Peruana Cayetano Heredia, Lima, Perú
| | - D. Montes
- YAVACUS, Yavarí Conservación y Uso Sostenible, Iquitos, Perú
| | - C. González-Crespo
- Departament de Medicina i Cirurgia Animals, Servei d' Ecopatologia de Fauna Salvatge (SEFaS), Faculty of Veterinary, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain
| | | | - M. Bowler
- San Diego Zoo Global, Institute for Conservation Research, Escondido, CA, USA
- School of Psychology and Neuroscience, University of St Andrews, St Andrews, UK
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Widdig A, Kessler MJ, Bercovitch FB, Berard JD, Duggleby C, Nürnberg P, Rawlins RG, Sauermann U, Wang Q, Krawczak M, Schmidtke J. Genetic studies on the Cayo Santiago rhesus macaques: A review of 40 years of research. Am J Primatol 2015; 78:44-62. [PMID: 26031601 DOI: 10.1002/ajp.22424] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 04/17/2015] [Accepted: 04/19/2015] [Indexed: 01/17/2023]
Abstract
Genetic studies not only contribute substantially to our current understanding of the natural variation in behavior and health in many species, they also provide the basis of numerous in vivo models of human traits. Despite the many challenges posed by the high level of biological and social complexity, a long lifespan and difficult access in the field, genetic studies of primates are particularly rewarding because of the close evolutionary relatedness of these species to humans. The free-ranging rhesus macaque (Macaca mulatta) population on Cayo Santiago (CS), Puerto Rico, provides a unique resource in this respect because several of the abovementioned caveats are of either minor importance there, or lacking altogether, thereby allowing long-term genetic research in a primate population under constant surveillance since 1956. This review summarizes more than 40 years of genetic research carried out on CS, from early blood group typing and the genetic characterization of skeletal material via population-wide paternity testing with DNA fingerprints and short tandem repeats (STRs) to the analysis of the highly polymorphic DQB1 locus within the major histocompatibility complex (MHC). The results of the paternity studies also facilitated subsequent studies of male dominance and other factors influencing male reproductive success, of male reproductive skew, paternal kin bias, and mechanisms of paternal kin recognition. More recently, the CS macaques have been the subjects of functional genetic and gene expression analyses and have played an important role in behavioral and quantitative genetic studies. In addition, the CS colony has been used as a natural model for human adult-onset macular degeneration, glaucoma, and circadian rhythm disorder. Our review finishes off with a discussion of potential future directions of research on CS, including the transition from STRs to single nucleotide polymorphism (SNP) typing and whole genome sequencing.
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Affiliation(s)
- Anja Widdig
- Research Group of Behavioural Ecology, Institute of Biology, University of Leipzig, Leipzig, Germany.,Junior Research Group of Primate Kin Selection, Department of Primatology, Max-Planck Institute for Evolutionary Anthropology, Leipzig, Germany.,Caribbean Primate Research Center, University of Puerto Rico, Punta Santiago, Puerto Rico
| | - Matthew J Kessler
- Caribbean Primate Research Center, University of Puerto Rico, Punta Santiago, Puerto Rico.,Division of Laboratory Animal Resources, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, West Virginia
| | - Fred B Bercovitch
- Primate Research Institute & Wildlife Research Center, Kyoto University, Inuyama, Aichi, Japan
| | - John D Berard
- Department of Veterans Affairs, Greater Los Angeles Health Care System, North Hills, California
| | - Christine Duggleby
- Department of Anthropology, State University of New York at Buffalo, Buffalo, New York
| | - Peter Nürnberg
- Cologne Center for Genomics, University of Cologne, Köln, Germany
| | - Richard G Rawlins
- Caribbean Primate Research Center, University of Puerto Rico, Punta Santiago, Puerto Rico
| | - Ulrike Sauermann
- Unit of Infection Models, German Primate Center, Göttingen, Germany
| | - Qian Wang
- Department of Biomedical Sciences, Texas A&M University Baylor College of Dentistry, Texas
| | - Michael Krawczak
- Institute of Medical Informatics and Statistics, Christian-Albrechts University of Kiel, Kiel, Germany
| | - Jörg Schmidtke
- Institute of Human Genetics, Hannover Medical School, Hannover, Germany
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47
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Georgiev AV, Muehlenbein MP, Prall SP, Emery Thompson M, Maestripieri D. Male quality, dominance rank, and mating success in free-ranging rhesus macaques. Behav Ecol 2015. [DOI: 10.1093/beheco/arv008] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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48
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Hughes KD, Higham JP, Allen WL, Elliot AJ, Hayden BY. Extraneous color affects female macaques' gaze preference for photographs of male conspecifics. EVOL HUM BEHAV 2015; 36:25-31. [PMID: 25530698 PMCID: PMC4269239 DOI: 10.1016/j.evolhumbehav.2014.08.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Humans find members of the opposite sex more attractive when their image is spatially associated with the color red. This effect even occurs when the red color is not on the skin or clothing (i.e. is extraneous). We hypothesize that this extraneous color effect could be at least partially explained by a low-level and biologically innate generalization process, and so similar extraneous color effects should be observed in non-humans. To test this possibility, we examined the influence of extraneous color in rhesus macaques (Macaca mulatta). Across two experiments, we determined the influence of extraneous red on viewing preferences (assessed by looking time) in free-ranging rhesus monkeys. We presented male and female monkeys with black and white photographs of the hindquarters of same and opposite sex conspecifics on either a red (experimental condition) or blue (control condition) background. As a secondary control, we also presented neutral stimuli (photographs of seashells) on red and blue backgrounds. We found that female monkeys looked longer at a picture of a male scrotum, but not a seashell, on a red background (Experiment 1), while males showed no bias. Neither male nor female monkeys showed an effect of color on looking time for female hindquarters or seashells (Experiment 2). The finding for females viewing males suggests that extraneous color affects preferences among rhesus macaques. Further, it raises the possibility that evolutionary processes gave rise to extraneous color effects during human evolution.
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Affiliation(s)
- Kelly D Hughes
- Department of Brain and Cognitive Science, University of Rochester
| | | | | | - Andrew J Elliot
- Department of Social and Clinical Psychology, University of Rochester
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49
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Dubuc C, Winters S, Allen WL, Brent LJN, Cascio J, Maestripieri D, Ruiz-Lambides AV, Widdig A, Higham JP. Sexually selected skin colour is heritable and related to fecundity in a non-human primate. Proc Biol Sci 2014; 281:20141602. [PMID: 25253459 PMCID: PMC4211451 DOI: 10.1098/rspb.2014.1602] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Accepted: 08/26/2014] [Indexed: 11/12/2022] Open
Abstract
Sexual selection promotes the prevalence of heritable traits that increase an individual's reproductive rate. Despite theoretically strong directional selection, sexually selected traits can show inter-individual variation. Here, we investigate whether red skin ornamentation, a rare example of a male mammalian trait involved in mate attraction, influences fecundity and is heritable in rhesus macaques (Macaca mulatta), and explore the mechanisms that are involved in maintaining trait variation. Interestingly, the trait is expressed by and is attractive to both sexes. We collected facial images of 266 free-ranging individuals and modelled skin redness and darkness to rhesus macaque vision. We used 20 years of genetic parentage data to calculate selection gradients on the trait and perform heritability analyses. Results show that males who were both darkly coloured and high-ranking enjoyed higher fecundity. Female skin redness was positively linked to fecundity, although it remains unclear whether this influences male selectiveness. Heritability explained 10-15% of the variation in redness and darkness, and up to 30% for skin darkness when sexes are considered separately, suggesting sex-influenced inheritance. Our results suggest that inter-individual variation is maintained through condition-dependence, with an added effect of balancing selection on male skin darkness, providing rare evidence for a mammalian trait selected through inter-sexual selection.
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Affiliation(s)
- Constance Dubuc
- Center for the Study of Human Origins, Department of Anthropology, New York University, 25 Waverly Place, New York, NY 10003, USA
| | - Sandra Winters
- Center for the Study of Human Origins, Department of Anthropology, New York University, 25 Waverly Place, New York, NY 10003, USA
| | - William L Allen
- Center for the Study of Human Origins, Department of Anthropology, New York University, 25 Waverly Place, New York, NY 10003, USA
| | - Lauren J N Brent
- Duke Institute for Brain Sciences and Center for Cognitive Neuroscience, Duke University, 450 Research Drive, Durham, NC 27708, USA
| | - Julie Cascio
- Center for the Study of Human Origins, Department of Anthropology, New York University, 25 Waverly Place, New York, NY 10003, USA
| | - Dario Maestripieri
- Institute for Mind and Biology, University of Chicago, Chicago, IL 60637, USA Department of Comparative Human Development, University of Chicago, Chicago, IL 60637, USA
| | - Angelina V Ruiz-Lambides
- Cayo Santiago, Caribbean Primate Research Center, University of Puerto Rico, Medical Sciences Campus, PO Box 906, Punta Santiago, PR 00741, USA Junior Research Group of Primate Kin Selection, Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, Leipzig 04103, Germany
| | - Anja Widdig
- Junior Research Group of Primate Kin Selection, Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, Leipzig 04103, Germany Institute of Biology, Faculty of Bioscience, Pharmacy and Psychology, University of Leipzig, Talstrasse 33, Leipzig 04103, Germany
| | - James P Higham
- Center for the Study of Human Origins, Department of Anthropology, New York University, 25 Waverly Place, New York, NY 10003, USA
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50
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Higham JP, Maestripieri D. The Costs of Reproductive Success in Male Rhesus Macaques (Macaca mulatta) on Cayo Santiago. INT J PRIMATOL 2014. [DOI: 10.1007/s10764-014-9789-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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