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Wen X, Wang F, Tang T, Xu B, Yuan M, Li Y, Ding H, Tao F, Su P, Wang G. Sex-specific association of peripheral blood cell indices and inflammatory markers with depressive symptoms in early adolescence. J Affect Disord 2024; 362:134-144. [PMID: 38960333 DOI: 10.1016/j.jad.2024.06.098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 05/30/2024] [Accepted: 06/25/2024] [Indexed: 07/05/2024]
Abstract
BACKGROUND Previous studies have reported the correlation of dysregulated blood cell indices and peripheral inflammatory markers with depression in adults but limited studies have examined this correlation in early adolescents. METHODS This study used data from the Chinese Early Adolescents Cohort Study, which was conducted in Anhui, China. Students' depression symptoms were repeatedly measured using the Chinese version of the Center for Epidemiological Studies Depression Scale for Children. Students' blood samples were collected in September 2019 and September 2021. The peripheral blood cell counts and inflammatory marker levels were determined using routine blood tests. Multivariable regression models were used to explore the associations between blood cell indices and adolescent depressive symptoms in both the whole sample and the sex-stratified samples. RESULTS The white blood cell (WBC) count, neutrophil count (NC), platelet (PLT) count, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio, and systemic immune inflammation index (SII) were positively correlated with the severity of depressive symptoms during follow-up. The mean corpuscular volume (MCV), mean hemoglobin (HGB) volume (MCH), and mean corpuscular HGB concentration (MCHC) exhibited negative temporal correlations with depressive symptoms. Additionally, several sex-specific blood cell markers were correlated with depression. Male adolescents with increased red blood cell (RBC) and female adolescents with decreased HGB levels and upregulated WBC, NC, NLR, and SII levels exhibited severe depressive symptoms at follow-up. CONCLUSIONS These findings suggested the potential usefulness of peripheral blood cell indices in the assessment of depression in early adolescents.
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Affiliation(s)
- Xue Wen
- Department of Maternal, Child and Adolescent Health, School of Public Health, Anhui Medical University, No. 81 Meishan Road, Hefei 230032, Anhui, China
| | - Fan Wang
- Department of Maternal, Child and Adolescent Health, School of Public Health, Anhui Medical University, No. 81 Meishan Road, Hefei 230032, Anhui, China
| | - Ting Tang
- Department of Maternal, Child and Adolescent Health, School of Public Health, Anhui Medical University, No. 81 Meishan Road, Hefei 230032, Anhui, China
| | - Baoyu Xu
- Department of Maternal, Child and Adolescent Health, School of Public Health, Anhui Medical University, No. 81 Meishan Road, Hefei 230032, Anhui, China
| | - Mengyuan Yuan
- Department of Maternal, Child and Adolescent Health, School of Public Health, Anhui Medical University, No. 81 Meishan Road, Hefei 230032, Anhui, China
| | - Yonghan Li
- Department of Maternal, Child and Adolescent Health, School of Public Health, Anhui Medical University, No. 81 Meishan Road, Hefei 230032, Anhui, China
| | - Han Ding
- Department of Maternal, Child and Adolescent Health, School of Public Health, Anhui Medical University, No. 81 Meishan Road, Hefei 230032, Anhui, China
| | - Fangbiao Tao
- Department of Maternal, Child and Adolescent Health, School of Public Health, Anhui Medical University, No. 81 Meishan Road, Hefei 230032, Anhui, China; Key Laboratory of Population Health Across Life Cycle (Anhui Medical University), Ministry of Education of the People's Republic of China, No. 81 Meishan Road, Hefei 230032, Anhui, China; Anhui Provincial Key Laboratory of Population Health and Aristogenics, No. 81 Meishan Road, Hefei 230032, Anhui, China
| | - Puyu Su
- Department of Maternal, Child and Adolescent Health, School of Public Health, Anhui Medical University, No. 81 Meishan Road, Hefei 230032, Anhui, China; Key Laboratory of Population Health Across Life Cycle (Anhui Medical University), Ministry of Education of the People's Republic of China, No. 81 Meishan Road, Hefei 230032, Anhui, China; Anhui Provincial Key Laboratory of Population Health and Aristogenics, No. 81 Meishan Road, Hefei 230032, Anhui, China.
| | - Gengfu Wang
- Department of Maternal, Child and Adolescent Health, School of Public Health, Anhui Medical University, No. 81 Meishan Road, Hefei 230032, Anhui, China; Key Laboratory of Population Health Across Life Cycle (Anhui Medical University), Ministry of Education of the People's Republic of China, No. 81 Meishan Road, Hefei 230032, Anhui, China; Anhui Provincial Key Laboratory of Population Health and Aristogenics, No. 81 Meishan Road, Hefei 230032, Anhui, China.
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Kailing MJ, Hoyt JR, White JP, Kaarakka HM, Redell JA, Leon AE, Rocke TE, DePue JE, Scullon WH, Parise KL, Foster JT, Kilpatrick AM, Langwig KE. Sex-biased infections scale to population impacts for an emerging wildlife disease. Proc Biol Sci 2023; 290:20230040. [PMID: 36946110 PMCID: PMC10031401 DOI: 10.1098/rspb.2023.0040] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 02/22/2023] [Indexed: 03/23/2023] Open
Abstract
Demographic factors are fundamental in shaping infectious disease dynamics. Aspects of populations that create structure, like age and sex, can affect patterns of transmission, infection intensity and population outcomes. However, studies rarely link these processes from individual to population-scale effects. Moreover, the mechanisms underlying demographic differences in disease are frequently unclear. Here, we explore sex-biased infections for a multi-host fungal disease of bats, white-nose syndrome, and link disease-associated mortality between sexes, the distortion of sex ratios and the potential mechanisms underlying sex differences in infection. We collected data on host traits, infection intensity and survival of five bat species at 42 sites across seven years. We found females were more infected than males for all five species. Females also had lower apparent survival over winter and accounted for a smaller proportion of populations over time. Notably, female-biased infections were evident by early hibernation and likely driven by sex-based differences in autumn mating behaviour. Male bats were more active during autumn which likely reduced replication of the cool-growing fungus. Higher disease impacts in female bats may have cascading effects on bat populations beyond the hibernation season by limiting recruitment and increasing the risk of Allee effects.
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Affiliation(s)
- Macy J. Kailing
- Department of Biological Sciences, Virginia Polytechnic Institute, Blacksburg, VA 24061, USA
| | - Joseph R. Hoyt
- Department of Biological Sciences, Virginia Polytechnic Institute, Blacksburg, VA 24061, USA
| | - J. Paul White
- Wisconsin Department of Natural Resources, Madison, WI 53707, USA
| | | | | | - Ariel E. Leon
- US Geological Survey, National Wildlife Health Center, Madison, WI 53711, USA
| | - Tonie E. Rocke
- US Geological Survey, National Wildlife Health Center, Madison, WI 53711, USA
| | - John E. DePue
- Michigan Department of Natural Resources, Baraga, MI 49908, USA
| | | | - Katy L. Parise
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Jeffrey T. Foster
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - A. Marm Kilpatrick
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA 95060, USA
| | - Kate E. Langwig
- Department of Biological Sciences, Virginia Polytechnic Institute, Blacksburg, VA 24061, USA
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3
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Figueiredo ACD, Titon SC, Titon Jr. B, Vasconcelos-Teixeira R, Barsotti AM, Gomes FR. Systemic hormonal and immune regulation induced by intraperitoneal LPS injection in bullfrogs (Lithobates catesbeianus). Comp Biochem Physiol A Mol Integr Physiol 2021; 253:110872. [DOI: 10.1016/j.cbpa.2020.110872] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 12/09/2020] [Accepted: 12/09/2020] [Indexed: 01/09/2023]
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Lindsay WR, Andersson S, Bererhi B, Höglund J, Johnsen A, Kvarnemo C, Leder EH, Lifjeld JT, Ninnes CE, Olsson M, Parker GA, Pizzari T, Qvarnström A, Safran RJ, Svensson O, Edwards SV. Endless forms of sexual selection. PeerJ 2019; 7:e7988. [PMID: 31720113 PMCID: PMC6839514 DOI: 10.7717/peerj.7988] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 10/04/2019] [Indexed: 12/11/2022] Open
Abstract
In recent years, the field of sexual selection has exploded, with advances in theoretical and empirical research complementing each other in exciting ways. This perspective piece is the product of a "stock-taking" workshop on sexual selection and sexual conflict. Our aim is to identify and deliberate on outstanding questions and to stimulate discussion rather than provide a comprehensive overview of the entire field. These questions are organized into four thematic sections we deem essential to the field. First we focus on the evolution of mate choice and mating systems. Variation in mate quality can generate both competition and choice in the opposite sex, with implications for the evolution of mating systems. Limitations on mate choice may dictate the importance of direct vs. indirect benefits in mating decisions and consequently, mating systems, especially with regard to polyandry. Second, we focus on how sender and receiver mechanisms shape signal design. Mediation of honest signal content likely depends on integration of temporally variable social and physiological costs that are challenging to measure. We view the neuroethology of sensory and cognitive receiver biases as the main key to signal form and the 'aesthetic sense' proposed by Darwin. Since a receiver bias is sufficient to both initiate and drive ornament or armament exaggeration, without a genetically correlated or even coevolving receiver, this may be the appropriate 'null model' of sexual selection. Thirdly, we focus on the genetic architecture of sexually selected traits. Despite advances in modern molecular techniques, the number and identity of genes underlying performance, display and secondary sexual traits remains largely unknown. In-depth investigations into the genetic basis of sexual dimorphism in the context of long-term field studies will reveal constraints and trajectories of sexually selected trait evolution. Finally, we focus on sexual selection and conflict as drivers of speciation. Population divergence and speciation are often influenced by an interplay between sexual and natural selection. The extent to which sexual selection promotes or counteracts population divergence may vary depending on the genetic architecture of traits as well as the covariance between mating competition and local adaptation. Additionally, post-copulatory processes, such as selection against heterospecific sperm, may influence the importance of sexual selection in speciation. We propose that efforts to resolve these four themes can catalyze conceptual progress in the field of sexual selection, and we offer potential avenues of research to advance this progress.
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Affiliation(s)
- Willow R. Lindsay
- Department of Biological and Environmental Sciences, University of Gothenburg, Göteborg, Sweden
| | - Staffan Andersson
- Department of Biological and Environmental Sciences, University of Gothenburg, Göteborg, Sweden
| | - Badreddine Bererhi
- Department of Biological and Environmental Sciences, University of Gothenburg, Göteborg, Sweden
| | - Jacob Höglund
- Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden
| | - Arild Johnsen
- Natural History Museum, University of Oslo, Oslo, Norway
| | - Charlotta Kvarnemo
- Department of Biological and Environmental Sciences, University of Gothenburg, Göteborg, Sweden
| | - Erica H. Leder
- Natural History Museum, University of Oslo, Oslo, Norway
| | - Jan T. Lifjeld
- Natural History Museum, University of Oslo, Oslo, Norway
| | - Calum E. Ninnes
- Department of Biological and Environmental Sciences, University of Gothenburg, Göteborg, Sweden
- Department of Entomology and Nematology, University of Florida, Gainesville, FL, United States of America
| | - Mats Olsson
- Department of Biological and Environmental Sciences, University of Gothenburg, Göteborg, Sweden
| | - Geoff A. Parker
- Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Tommaso Pizzari
- Department of Zoology, Edward Grey Institute, University of Oxford, Oxford, United Kingdom
| | - Anna Qvarnström
- Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden
| | - Rebecca J. Safran
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, United States of America
| | - Ola Svensson
- School of Natural Sciences, Technology and Environmental Studies, Södertörn University, Huddinge, Sweden
| | - Scott V. Edwards
- Department of Organismic and Evolutionary Biology and Museum of Comparative Zoology, Harvard University, Cambridge, MA, United States of America
- Gothenburg Centre for Advanced Studies in Science and Technology, Chalmers University of Technology, Göteborg, Sweden
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Arathimos R, Granell R, Haycock P, Richmond RC, Yarmolinsky J, Relton CL, Tilling K. Genetic and observational evidence supports a causal role of sex hormones on the development of asthma. Thorax 2019; 74:633-642. [PMID: 30936389 PMCID: PMC6585308 DOI: 10.1136/thoraxjnl-2018-212207] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 11/14/2018] [Accepted: 11/26/2018] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Males have a higher prevalence of asthma in childhood, whereas females have a higher prevalence in adolescence and adulthood. The 'adolescent switch' observed between sexes during puberty has been hypothesised to be due to fluctuating sex hormones. Robust evidence of the involvement of sex hormones in asthma could lead to development of therapeutic interventions. METHODS We combine observational evidence using longitudinal data on sex hormone-binding globulin (SHBG), total and bioavailable testosterone and asthma from a subset of males (n=512) in the Avon Longitudinal Study of Parents and Children, and genetic evidence of SHBG and asthma using two-sample Mendelian randomisation (MR), a method of causal inference. We meta-analysed two-sample MR results across two large data sets, the Trans-National Asthma Genetics Consortium genome-wide association study of asthma and UK Biobank (over 460 000 individuals combined). RESULTS Observational evidence indicated weak evidence of a protective effect of increased circulating testosterone on asthma in males in adolescence, but no strong pattern of association with SHBG. Genetic evidence using two-sample MR indicated a protective effect of increased SHBG, with an OR for asthma of 0.86 (95% CI 0.74 to 1.00) for the inverse-variance weighted approach and an OR of 0.83 (95% CI 0.72 to 0.96) for the weighted median estimator, per unit increase in natural log SHBG. A sex-stratified sensitivity analysis suggested the protective effect of SHBG was mostly evident in females. CONCLUSION We report the first suggestive evidence of a protective effect of genetically elevated SHBG on asthma, which may provide a biological explanation behind the observed asthma sex discordance. Further work is required to disentangle the downstream effects of SHBG on asthma and the molecular pathways involved.
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Affiliation(s)
- Ryan Arathimos
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
- Medical Research Council Integrative Epidemiology Unit, University of Bristol, Bristol, UK
| | - Raquel Granell
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Philip Haycock
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
- Medical Research Council Integrative Epidemiology Unit, University of Bristol, Bristol, UK
| | - Rebecca C Richmond
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
- Medical Research Council Integrative Epidemiology Unit, University of Bristol, Bristol, UK
| | - James Yarmolinsky
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
- Medical Research Council Integrative Epidemiology Unit, University of Bristol, Bristol, UK
| | - Caroline L Relton
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
- Medical Research Council Integrative Epidemiology Unit, University of Bristol, Bristol, UK
| | - Kate Tilling
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
- Medical Research Council Integrative Epidemiology Unit, University of Bristol, Bristol, UK
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6
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Watkins H, Blouin-Demers G. Body size, not age, predicts parasite load in Clark’s Spiny Lizards (Sceloporus clarkii). CAN J ZOOL 2019. [DOI: 10.1139/cjz-2017-0328] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Determining the factors that influence parasite load is a fundamental goal of parasitology. Body size often influences parasite load in reptiles, but it is unclear whether higher levels of parasitism are a result of greater surface area of individuals (a function of size) or of longer periods of exposure to parasites (a function of age). Using skeletochronology in a wild population of Clark’s Spiny Lizards (Sceloporus clarkii Baird and Girard, 1852), we tested the hypotheses that (i) larger individuals have higher parasite loads due to increased surface area available for colonization by parasites and their vectors and that (ii) older individuals have higher parasite loads because they have had longer exposure to parasites and their vectors. Males harboured more ectoparasites than females. Males and females differed in how body size influenced chigger (Acari: Trombiculidae) load; larger males harboured more chiggers than smaller males, but this was not the case in females. Age did not affect ectoparasite load in either sex. These results emphasize the importance of disentangling the effects of size and age in models of parasitism to gain a clearer understanding of intraspecific variation in parasite load.
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Affiliation(s)
- H.V. Watkins
- Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5, Canada
- Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - G. Blouin-Demers
- Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5, Canada
- Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5, Canada
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7
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Escallón C, Belden LK, Moore IT. The Cloacal Microbiome Changes with the Breeding Season in a Wild Bird. Integr Org Biol 2019; 1:oby009. [PMID: 33791516 PMCID: PMC7671126 DOI: 10.1093/iob/oby009] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The symbiotic microbial communities, or “microbiomes,” that reside on animals are dynamic, and can be affected by the behavior and physiology of the host. These communities provide many critical beneficial functions for their hosts, but they can also include potential pathogens. In birds, bacteria residing in the cloaca form a complex community, including both gut and sexually-transmitted bacteria. Transmission of cloacal bacteria among individuals is likely during the breeding season, when there is direct cloacal contact between individuals. In addition, the major energetic investment in reproduction can draw resources away from immune responses that might otherwise prevent the successful establishment of microbes. We assessed dynamic variation in the cloacal microbiome of free-living rufous-collared sparrows (Zonotrichia capensis) through sequential breeding and non-breeding seasons. We found that the cloacal bacterial communities differed between the sexes when they were in breeding condition. Further, in males, but not in females, the bacterial community became more diverse with the onset of reproduction, and then decreased in diversity as males transitioned to non-breeding condition. Individuals sampled across sequential breeding seasons did not accumulate more bacterial taxa over seasons, but bacterial community composition did change. Our results suggest that the cloacal microbiome in birds is dynamic and, especially in males, responsive to breeding condition.
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Affiliation(s)
- C Escallón
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA.,Departamento de Ciencias Básicas, Universidad de La Salle, Cra 2 No. 10-70, Bogotá, Colombia
| | - L K Belden
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - I T Moore
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA
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9
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Rogovin KA, Khrushchova AM, Shekarova ON, Vasilieva NA, Vasilieva NY. Females choose gentle, but not healthy or macho males in Campbell dwarf hamsters ( Phodopus campbelli Thomas 1905). Curr Zool 2017; 63:545-554. [PMID: 29492014 PMCID: PMC5804195 DOI: 10.1093/cz/zow090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 08/11/2016] [Indexed: 11/29/2022] Open
Abstract
Androgen-dependent male sexual traits (STs) as well as immunocompetence are theoretically assumed to be key indicators of a male's quality for the mate-choosing female. We studied mate choice by sexually motivated (SM) females of Campbell's dwarf hamsters. Females chose between 2 tethered male siblings that differed in expression of STs. Males were unrelated to the female and able to contact and copulate with her. In both males, we measured sex-related morphology of body mass, mid-ventral specific skin gland, ano-genital distance, and external testicular diameter. We also estimated levels of blood testosterone and cortisol, specific T- and B-cell immune responses to antigens, as well as aggressive and sexual dominance in sibling males through additional encounter experiments with another SM female (male sibs could freely compete for the female). We found that SM females chose a partner among 2 male sibs and spent over 80% of their time on average with the preferred male compared with the non-preferred one. Her choice was not associated with the first visit of the chosen male, with a higher expression of sex-related traits, higher levels of blood testosterone, or with aggressive dominance. The choice was not associated with the intensity of T-cell immune response to phitohemagglutinin (PHA). Instead there was a tendency for a negative relationship with the expression of STs and B-cell response to the antigen challenge. The only character that unambiguously influenced female choice was the non-aggressive male to female grooming during sexual contact. There was no difference in breeding success between preferred and non-preferred males paired with virgin females.
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Affiliation(s)
- Konstantin A. Rogovin
- A.N. Severtsov Institute of Ecology and Evolution, RAS, Leninskii prospect 33, Moscow 119071, Russia
| | - Anastasiya M. Khrushchova
- A.N. Severtsov Institute of Ecology and Evolution, RAS, Leninskii prospect 33, Moscow 119071, Russia
| | - Olga N. Shekarova
- A.N. Severtsov Institute of Ecology and Evolution, RAS, Leninskii prospect 33, Moscow 119071, Russia
| | - Nina A. Vasilieva
- A.N. Severtsov Institute of Ecology and Evolution, RAS, Leninskii prospect 33, Moscow 119071, Russia
| | - Nina Yu Vasilieva
- A.N. Severtsov Institute of Ecology and Evolution, RAS, Leninskii prospect 33, Moscow 119071, Russia
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Ezenwa VO, Snider MH. Reciprocal relationships between behaviour and parasites suggest that negative feedback may drive flexibility in male reproductive behaviour. Proc Biol Sci 2017; 283:rspb.2016.0423. [PMID: 27194703 DOI: 10.1098/rspb.2016.0423] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 04/22/2016] [Indexed: 12/21/2022] Open
Abstract
Parasites are ubiquitous components of the environment that contribute to behavioural and life-history variation among hosts. Although it is well known that host behaviour can affect parasite infection risk and that parasites can alter host behaviour, the potential for dynamic feedback between these processes is poorly characterized. Using Grant's gazelle (Nanger granti) as a model, we tested for reciprocal effects of behaviour on parasites and parasites on behaviour to understand whether behaviour-parasite feedback could play a role in maintaining variation in male reproductive behaviour. Adult male gazelles either defend territories to attract mates or reside in bachelor groups. Territoriality is highly variable both within- and between-individuals, suggesting that territory maintenance is costly. Using a combination of longitudinal and experimental studies, we found that individual males transition frequently between territorial and bachelor reproductive status, and that elevated parasite burdens are a cost of territoriality. Moreover, among territorial males, parasites suppress aspects of behaviour related to territory maintenance and defence. These results suggest that territorial behaviour promotes the accumulation of parasites in males, and these parasites dampen the very behaviours required for territory maintenance. Our findings suggest that reciprocal feedback between host behaviour and parasitism could be a mechanism maintaining variation in male reproductive behaviour in the system.
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Affiliation(s)
- Vanessa O Ezenwa
- Odum School of Ecology and Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
| | - Matthew H Snider
- Odum School of Ecology and Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
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11
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Segner H, Verburg-van Kemenade BML, Chadzinska M. The immunomodulatory role of the hypothalamus-pituitary-gonad axis: Proximate mechanism for reproduction-immune trade offs? DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2017; 66:43-60. [PMID: 27404794 DOI: 10.1016/j.dci.2016.07.004] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 07/06/2016] [Accepted: 07/07/2016] [Indexed: 06/06/2023]
Abstract
The present review discusses the communication between the hypothalamic-pituitary-gonad (HPG) axis and the immune system of vertebrates, attempting to situate the HPG-immune interaction into the context of life history trade-offs between reproductive and immune functions. More specifically, (i) we review molecular and cellular interactions between hormones of the HPG axis, and, as far as known, the involved mechanisms on immune functions, (ii) we evaluate whether the HPG-immune crosstalk serves as proximate mechanism mediating reproductive-immune trade-offs, and (iii) we ask whether the nature of the HPG-immune interaction is conserved throughout vertebrate evolution, despite the changes in immune functions, reproductive modes, and life histories. In all vertebrate classes studied so far, HPG hormones have immunomodulatory functions, and indications exist that they contribute to reproduction-immunity resource trade-offs, although the very limited information available for most non-mammalian vertebrates makes it difficult to judge how comparable or different the interactions are. There is good evidence that the HPG-immune crosstalk is part of the proximate mechanisms underlying the reproductive-immune trade-offs of vertebrates, but it is only one factor in a complex network of factors and processes. The fact that the HPG-immune interaction is flexible and can adapt to the functional and physiological requirements of specific life histories. Moreover, the assumption of a relatively fixed pattern of HPG influence on immune functions, with, for example, androgens always leading to immunosuppression and estrogens always being immunoprotective, is probably oversimplified, but the HPG-immune interaction can vary depending on the physiological and envoironmental context. Finally, the HPG-immune interaction is not only driven by resource trade-offs, but additional factors such as, for instance, the evolution of viviparity shape this neuroendocrine-immune relationship.
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Affiliation(s)
- Helmut Segner
- Centre for Fish and Wildlife Health, Dept of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, P.O. Box, CH-3001, Bern, Switzerland.
| | - B M Lidy Verburg-van Kemenade
- Cell Biology and Immunology Group, Dept. of Animal Sciences, Wageningen University, P.O. Box 338, 6700 AH, Wageningen, The Netherlands
| | - Magdalena Chadzinska
- Department of Evolutionary Immunology, Institute of Zoology, Jagiellonian University, Gronostajowa 9, 30-387, Krakow, Poland
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Body mass and immune function, but not bill coloration, predict dominance in female mallards. Behav Processes 2016; 131:59-67. [PMID: 27561967 DOI: 10.1016/j.beproc.2016.08.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 08/12/2016] [Accepted: 08/21/2016] [Indexed: 12/13/2022]
Abstract
Competition over indivisible resources is common and often costly. Therefore, selection should favor strategies, including efficient communication, that minimize unnecessary costs associated with such competition. For example, signaling enables competitors to avoid engaging in costly asymmetrical contests. Recently, bill coloration has been identified as an information-rich signal used by some birds to mediate aggressive interactions and we evaluated this possibility in female mallards Anas platyrhynchos. Specifically, we conducted two rounds of competitive interactions among groups of unfamiliar adult female ducks. By recording all aggressive behaviors exhibited by each individual, as well as the identity of attack recipients, we were able to assign dominance scores and evaluate links between numerous physiological, morphological, and experimental variables that we predicted would influence contest outcome and dominance. Contrary to our predictions, dominance was not linked to any aspect of bill coloration, access to dietary carotenoids during development, two of three measures of immune function, or ovarian follicle maturation. Instead, heavier birds were more dominant, as were those with reduced immune system responses to an experimentally administered external immunostimulant, phytohemagglutinin. These results suggest that visual signals are less useful during the establishment of dominance hierarchies within multi-individual scramble competitions, and that immune function is correlated with contest strategies in competitions for access to limited resources.
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Hanamsagar R, Bilbo SD. Sex differences in neurodevelopmental and neurodegenerative disorders: Focus on microglial function and neuroinflammation during development. J Steroid Biochem Mol Biol 2016; 160:127-33. [PMID: 26435451 PMCID: PMC4829467 DOI: 10.1016/j.jsbmb.2015.09.039] [Citation(s) in RCA: 234] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 09/25/2015] [Accepted: 09/28/2015] [Indexed: 12/12/2022]
Abstract
Several neurological conditions are associated with sex differences in prevalence or outcome. For example, autism predominantly affects boys, depression is more common in women, Parkinson's disease more common in men, and multiple sclerosis in women. In the case of stroke, women have a less favorable outcome and suffer from a more precipitous drop in health status compared to men. As a result, treatment of such diseases is difficult and yields variable results. Despite this, sex is rarely considered when making treatment decisions. The mechanisms underlying sex differences in disease progression are not well understood, however a strong link exists between different inflammation states of men and women and their propensity to develop certain diseases. As neuroinflammation is an important component of pathophysiology in many neurological conditions, it can be speculated that any changes in the state of inflammation in the brain during normal development can potentially lead to an increase in susceptibility to neurological and neurodegenerative diseases. Microglia play a crucial role in onset and modulation of inflammation and thus sex differences in microglial function could explain, at least in part, differences observed in susceptibilities and outcomes of neurological disorders in men and women. Understanding the mechanisms behind sex differences could help develop more targeted therapy with higher success rate, especially in diseases where sex differences are most prominent.
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Affiliation(s)
- Richa Hanamsagar
- Duke University, Department of Psychology & Neuroscience, Durham NC 27708, USA.
| | - Staci D Bilbo
- Duke University, Department of Psychology & Neuroscience, Durham NC 27708, USA.
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14
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Affiliation(s)
- Kimberly L. VanderWaal
- Department of Veterinary Population Medicine University of Minnesota 1365 Gortner Avenue St. Paul MN 55108 USA
| | - Vanessa O. Ezenwa
- Odum School of Ecology and Department of Infectious Diseases University of Georgia 140 East Green Street Athens GA 30602 USA
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15
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Foo YZ, Nakagawa S, Rhodes G, Simmons LW. The effects of sex hormones on immune function: a meta-analysis. Biol Rev Camb Philos Soc 2016; 92:551-571. [DOI: 10.1111/brv.12243] [Citation(s) in RCA: 220] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 10/30/2015] [Accepted: 11/06/2015] [Indexed: 11/30/2022]
Affiliation(s)
- Yong Zhi Foo
- ARC Centre of Excellence in Cognition and its Disorders, School of Psychology, University of Western Australia; 35 Stirling Hwy Crawley Western Australia 6009 Australia
- Centre for Evolutionary Biology, School of Animal Biology, University of Western Australia; 35 Stirling Hwy Crawley Western Australia 6009 Australia
| | - Shinichi Nakagawa
- Department of Zoology; University of Otago; 340 Great King Street Dunedin 9016 New Zealand
- Evolution & Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales; UNSW Sydney NSW 2052 Australia
| | - Gillian Rhodes
- ARC Centre of Excellence in Cognition and its Disorders, School of Psychology, University of Western Australia; 35 Stirling Hwy Crawley Western Australia 6009 Australia
| | - Leigh W. Simmons
- ARC Centre of Excellence in Cognition and its Disorders, School of Psychology, University of Western Australia; 35 Stirling Hwy Crawley Western Australia 6009 Australia
- Centre for Evolutionary Biology, School of Animal Biology, University of Western Australia; 35 Stirling Hwy Crawley Western Australia 6009 Australia
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16
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Delany FM, Byrne ML, Whittle S, Simmons JG, Olsson C, Mundy LK, Patton GC, Allen NB. Depression, immune function, and early adrenarche in children. Psychoneuroendocrinology 2016; 63:228-34. [PMID: 26492635 DOI: 10.1016/j.psyneuen.2015.10.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 10/05/2015] [Accepted: 10/05/2015] [Indexed: 12/30/2022]
Abstract
Despite consistent findings of an association between depression and immunity in adult and adolescent populations, little is known about the nature of this relationship at earlier ages. Studies of children have yielded mixed results, suggesting methodological confounds and/or the presence of significant moderating factors. Timing of adrenarche, the first phase of puberty that occurs during late childhood, is a plausible moderator of the depression-immunity relationship in late childhood due to its associations with both the immune system and psychological wellbeing. We hypothesized that: (1) a depression-immunity association exists in children, (2) this association is moderated by adrenarcheal timing, and, (3) this association is also moderated by gender. Data were drawn from a nested study of 103 participants (62 females, Mage=9.5, age range: 8.67-10.21 years) participating in a population based cohort study of the transition from childhood to adolescence (across puberty). Participants in this nested study completed the Children's Depression Inventory 2 (CDI-2) and provided morning saliva samples to measure immune markers (i.e., C-reactive protein, CRP; and secretory immunoglobulin A, SIgA). Using hierarchical regression, inflammation measured by CRP was positively associated with the negative mood/physical symptoms (NM/PS) subscale (β=0.23, t=2.33, p=0.022) of the CDI-2. A significant interaction effect of SIgA x adrenarcheal timing was found for NM/PS (β=-0.39, t=-2.19, p=0.031) and Interpersonal Problems (β=-0.47, t=-2.71, p=0.008). SIgA and NM/PS were positively associated for relatively late developers. SIgA and Interpersonal Problems were positively associated for late developers, and negatively associated for early developers. We suggest that both sets of findings might be partially explained by the immunosuppressive effect of the hormonal changes associated with earlier adrenarche, namely testosterone. These results also suggest that adrenarcheal timing has an effect on the association between depression and immunity, and is therefore an important measure in research with younger populations. Future research should utilize longitudinal designs to demonstrate direction of influence of variables, and use a broader range of pro- and anti-inflammatory markers.
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Affiliation(s)
- Faustina M Delany
- Melbourne School of Psychological Sciences, The University of Melbourne, Parkville, Victoria, Australia
| | | | - Sarah Whittle
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne & Melbourne Health, Victoria, Australia
| | - Julian G Simmons
- Melbourne School of Psychological Sciences, The University of Melbourne, Parkville, Victoria, Australia; Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne & Melbourne Health, Victoria, Australia; Murdoch Childrens Research Institute, Melbourne, Australia
| | - Craig Olsson
- Centre for Adolescent Health, The Royal Children's Hospital, Melbourne, Australia
| | - Lisa K Mundy
- Centre for Adolescent Health, The Royal Children's Hospital, Melbourne, Australia; Murdoch Childrens Research Institute, Melbourne, Australia; Department of Paediatrics, The University of Melbourne, Melbourne, Australia
| | - George C Patton
- Murdoch Childrens Research Institute, Melbourne, Australia; Department of Paediatrics, The University of Melbourne, Melbourne, Australia
| | - Nicholas B Allen
- Melbourne School of Psychological Sciences, The University of Melbourne, Parkville, Victoria, Australia; The University of Oregon, Eugene, OR, USA.
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17
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Crates RA, Sheldon BC, Garroway CJ. Causes and consequences of individual variation in the extent of post-juvenile moult in the blue titCyanistes caeruleus(Passeriformes: Paridae). Biol J Linn Soc Lond 2015. [DOI: 10.1111/bij.12588] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ross A. Crates
- Edward Grey Institute; University of Oxford; South Parks Road Oxford OX1 3PS UK
- Fenner School of Environment and Society; Australian National University; Canberra ACT 0200 Australia
| | - Ben C. Sheldon
- Edward Grey Institute; University of Oxford; South Parks Road Oxford OX1 3PS UK
| | - Colin J. Garroway
- Edward Grey Institute; University of Oxford; South Parks Road Oxford OX1 3PS UK
- Département de Sciences Biologiques; Université de Montréal; Montréal QC H2V 2S9 Canada
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18
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Merrill L, Stewart TE, González-Gómez PL, O'Loghlen AL, Wingfield JC, Ellis VA, Rothstein SI. Epaulet size and current condition in red-winged blackbirds: examining a semistatic signal, testosterone, immune function, and parasites. Physiol Biochem Zool 2015; 88:11-21. [PMID: 25590590 DOI: 10.1086/679475] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Some sexually selected signals are thought to convey information about the current condition and genetic/epigenetic quality of the individual signaling, including the ability to resist parasites. However, it is unclear whether semistatic sexual signals that develop periodically and remain stable over protracted periods, such as avian breeding plumage, can relate to measures of current condition and health. We examined a semistatic signal (wing epaulet size) in male red-winged blackbirds (Agelaius phoeniceus) during the breeding season and looked for relationships between this trait and circulating testosterone (T), hematocrit, bacteria-killing ability (BKA) of the blood, and the infection status, richness, and abundance of four functional categories of parasite. We found that epaulet size was positively related to circulating levels of T and ectoparasite infections. We found no relationships between T and parasite infections. In adult males there was a negative relationship between T and BKA, whereas in yearling males there was no relationship. We found no evidence for a general reduction in immunocompetence in males with larger epaulets but rather an increase in susceptibility to specific types of parasites. Our results suggest that semistatic signals can be linked to measures of current condition, and we postulate that these relationships are modulated via activity levels related to breeding-season activities.
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Affiliation(s)
- Loren Merrill
- Illinois Natural History Survey, University of Illinois, Urbana-Champaign, Illinois 61820; 2Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, California 93106; 3Department of Animal Biology, University of Illinois, Urbana-Champaign, Illinois 61820; 4Department of Neurobiology, Physiology and Behavior, University of California, Davis, California 95616; 5Department of Biology, University of Missouri, St. Louis, Missouri 63121
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19
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A test of the effect of testosterone on a sexually selected carotenoid trait in a cardueline finch. Ecol Res 2014. [DOI: 10.1007/s11284-014-1201-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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21
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O'Neal DM. Eco-endo-immunology across avian life history stages. Gen Comp Endocrinol 2013; 190:105-11. [PMID: 23707379 DOI: 10.1016/j.ygcen.2013.05.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 05/10/2013] [Accepted: 05/13/2013] [Indexed: 11/28/2022]
Abstract
Broadly distributed songbirds, particularly those that migrate, encounter a wide range of pathogens. Both pathogen exposure and energy available for immune responses are expected to be affected by environmental variation in climate, habitat quality, and social interactions as well as hormonal mechanisms. Comparisons of Aves in the field have begun to build the framework for understanding how such environmental variation interacts with disease environments as reflected in endocrine and immune responses. In this review, the roles of hormones and immune function across the various life history stages that make up the avian annual cycle are considered with an emphasis on free-living songbirds and the various hormones known to mediate the innate and acquired immune systems including melatonin, prolactin, growth hormone, and several neuroendocrine hormones. Finally, hormone-immune interactions are considered within the framework of disease ecology.
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Affiliation(s)
- Dawn M O'Neal
- Huyck Preserve and Biological Research Station, P.O. Box 189, Rensselaerville, NY 12147, USA.
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22
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Schwarz JM, Bilbo SD. Sex, glia, and development: interactions in health and disease. Horm Behav 2012; 62:243-53. [PMID: 22387107 PMCID: PMC3374064 DOI: 10.1016/j.yhbeh.2012.02.018] [Citation(s) in RCA: 184] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Revised: 02/14/2012] [Accepted: 02/15/2012] [Indexed: 12/14/2022]
Abstract
Microglia and astrocytes are the primary immune cells within the central nervous system. Microglia influence processes including neural development, synaptic plasticity and cognition; while their activation and production of immune molecules can induce stereotyped sickness behaviors or pathologies including cognitive dysfunction. Given their role in health and disease, we propose that glia may also be a critical link in understanding the etiology of many neuropsychiatric disorders that present with a strong sex-bias in their symptoms or prevalence. Specifically, males are more likely to be diagnosed with disorders that have distinct developmental origins such as autism or schizophrenia. In contrast, females are more likely to be diagnosed with disorders that present later in life, after the onset of adolescence, such as depression and anxiety disorders. In this review we will summarize the evidence suggesting that sex differences in the colonization and function of glia within the normal developing brain may contribute to distinct windows of vulnerability between males and females. We will also highlight the current gaps in our knowledge as well as the future directions and considerations of research aimed at understanding the link between neuroimmune function and sex differences in mental health disorders.
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Affiliation(s)
- Jaclyn M Schwarz
- Department of Psychology and Neuroscience, Duke University, 572 Research Dr. Rm 3017, Durham, NC 27705, USA.
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23
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Encarnação JA, Baulechner D, Becker NI. Seasonal Variations of Wing Mite Infestations in Male Daubenton'S Bats (Myotis daubentonii) in Comparison to Female and Juvenile Bats. ACTA CHIROPTEROLOGICA 2012. [DOI: 10.3161/150811012x654367] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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24
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Puts DA, Jones BC, DeBruine LM. Sexual selection on human faces and voices. JOURNAL OF SEX RESEARCH 2012; 49:227-243. [PMID: 22380590 DOI: 10.1080/00224499.2012.658924] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Humans are highly sexually dimorphic primates, and some of the most conspicuous human sex differences occur in the face and voice. Consequently, this article utilizes research findings on human faces and voices to illustrate how human sex differences may have arisen by sexual selection (i.e., the type of natural selection favoring traits that increase mating opportunities). Evidence suggesting that sexual selection shaped women's faces and voices is reviewed. However, sexual selection likely operated more strongly on men over human evolution. Thus, this research focuses on two types of sexual selection operating on men: female mate choice, which favors traits that attract females, and male contests, which favor traits for excluding competitors from mates by force or threat of force. This article demonstrates how masculine faces and voices advertize critical information about men's mate value and threat potential, and reviews evidence that women's preferences and men's deference to masculine faces and voices reflect this information content. Data suggesting that facial and vocal masculinity influences men's mating opportunities and reproduction are discussed, and the article concludes by highlighting directions for future research.
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Affiliation(s)
- David A Puts
- Department of Anthropology, Pennsylvania State University, University Park, PA 16802, USA.
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25
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Ezenwa VO, Stefan Ekernas L, Creel S. Unravelling complex associations between testosterone and parasite infection in the wild. Funct Ecol 2011. [DOI: 10.1111/j.1365-2435.2011.01919.x] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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26
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Lindsay WR, Webster MS, Schwabl H. Sexually selected male plumage color is testosterone dependent in a tropical passerine bird, the red-backed fairy-wren (Malurus melanocephalus). PLoS One 2011; 6:e26067. [PMID: 21998753 PMCID: PMC3187837 DOI: 10.1371/journal.pone.0026067] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2011] [Accepted: 09/19/2011] [Indexed: 11/18/2022] Open
Abstract
Background Sexual signals, such as bright plumage coloration in passerine birds, reflect individual quality, and testosterone (T) may play a critical role in maintaining signal honesty. Manipulations of T during molt have yielded mixed effects on passerine plumage color, in most cases delaying molt or leading to production of drab plumage. However, the majority of these studies have been conducted on species that undergo a post-nuptial molt when T is low; the role of T in species that acquire breeding plumage during a pre-nuptial molt remains largely unexplored. Methodology/Principal Findings We experimentally tested the effects of increased T on plumage color in second-year male red-backed fairy-wrens (Malurus melanocephalus), a species in which after-second-year males undergo a pre-nuptial molt into red/black (carotenoid and melanin-based) plumage and second-year males either assume red/black or brown breeding plumage. T treatment stimulated a rapid and early onset pre-nuptial molt and resulted in red/black plumage acquisition, bill darkening, and growth of the sperm storage organ, but had no effect on body condition or corticosterone concentrations. Control males molted later and assumed brown plumage. T treated males produced feathers with similar but not identical reflectance parameters to those of unmanipulated after-second-year red/black males; while reflectance spectra of red back and black crown feathers were similar, black breast feathers differed in UV chroma, hue and brightness, indicating a potentially age and plumage patch-dependent response to T for melanin- vs. carotenoid-pigmentation. Conclusions/Significance We show that testosterone is the primary mechanism functioning during the pre-nuptial molt to regulate intrasexually variable plumage color and breeding phenotype in male red-backed fairy-wrens. Our results suggest that the effects of T on plumage coloration may vary with timing of molt (pre- vs. post-nuptial), and that the role of T in mediating plumage signal production may differ across age classes, plumage patches, and between pigment-types.
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Affiliation(s)
- Willow R. Lindsay
- School of Biological Sciences and Center for Reproductive Biology, Washington State University, Pullman, Washington, United States of America
- * E-mail:
| | - Michael S. Webster
- Cornell Lab of Ornithology and Department of Neurobiology and Behavior, Cornell University, Ithaca, New York, United States of America
| | - Hubert Schwabl
- School of Biological Sciences and Center for Reproductive Biology, Washington State University, Pullman, Washington, United States of America
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27
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Ibáñez-Álamo JD, Chastel O, Soler M. Hormonal response of nestlings to predator calls. Gen Comp Endocrinol 2011; 171:232-6. [PMID: 21295574 DOI: 10.1016/j.ygcen.2011.01.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2010] [Revised: 01/15/2011] [Accepted: 01/28/2011] [Indexed: 11/19/2022]
Abstract
Chicks of altricial birds may perceive predation risk by acoustic cues produced by predators. This capacity involves changes to a less conspicuous behavior to avoid being detected and predated. However, little is known about the physiological mechanisms underlying this capacity. Potential mechanisms may involve corticosterone and testosterone, two hormones related to begging, an acoustic signal, which could be used by predators to locate and predate the nest. However, given the species-specificity of this relationship, it is difficult to make particular predictions. We manipulated perceived risk of nest predation in the common blackbird (Turdus merula) and analyzed nestlings' plasma levels of these hormones to look for nest predation risk effects. Our experimental manipulation showed hormonal changes in response to nest predation risk. Chicks under a high risk of nest predation reduced their corticosterone plasma levels but increased their testosterone levels in comparison with nestlings exposed to a low nest predation risk. We explain our results as mechanisms to reduce begging activity and discuss them within the framework of hormonal modifications in developing animals. These findings highlight the importance of studying nest predation from the unusually considered chick perspective and underlined the benefits from including physiological variables in the study of predator-prey interactions.
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Affiliation(s)
- J D Ibáñez-Álamo
- Departamento Biología Animal, Facultad de Ciencias, Universidad de Granada, CP 18071 Granada, Spain.
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28
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Smallegange IM. Effects of paternal phenotype and environmental variability on age and size at maturity in a male dimorphic mite. Naturwissenschaften 2011; 98:339-46. [PMID: 21387173 DOI: 10.1007/s00114-011-0773-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2011] [Revised: 02/14/2011] [Accepted: 02/15/2011] [Indexed: 10/18/2022]
Abstract
Investigating how the environment affects age and size at maturity of individuals is crucial to understanding how changes in the environment affect population dynamics through the biology of a species. Paternal phenotype, maternal, and offspring environment may crucially influence these traits, but to my knowledge, their combined effects have not yet been tested. Here, I found that in bulb mites (Rhizoglyphus robini), maternal nutrition, offspring nutrition, and paternal phenotype (males are fighters, able to kill other mites, or benign scramblers) interactively affected offspring age and size at maturity. The largest effect occurred when both maternal and offspring nutrition was poor: in that case offspring from fighter sires required a significantly longer development time than offspring from scrambler sires. Investigating parental effects on the relationship between age and size at maturity revealed no paternal effects, and only for females was its shape influenced by maternal nutrition. Overall, this reaction norm was nonlinear. These non-genetic intergenerational effects may play a complex, yet unexplored role in influencing population fluctuations-possibly explaining why results from field studies often do not match theoretical predictions on maternal effects on population dynamics.
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Peters A, Kurvers RHJM, Roberts ML, Delhey K. No evidence for general condition-dependence of structural plumage colour in blue tits: an experiment. J Evol Biol 2011; 24:976-87. [PMID: 21306464 DOI: 10.1111/j.1420-9101.2011.02229.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Condition-dependence is a central but contentious tenet of evolutionary theories on the maintenance of ornamental traits, and this is particularly true for structural plumage colour. By providing diets of different nutritional quality to moulting male and female blue tits, we experimentally manipulated general condition within the natural range, avoiding deprivation or stressful treatments. We measured reflectance of the structural-coloured UV/blue crown, a sexually selected trait in males, and the white cheek, a nonpigmented structural colour, directly after moult and again during the following spring mating season. We employed a variety of colour indices, based on spectral shape and avian visual models but, despite significant variation in condition and coloration, found no evidence for condition-dependence of UV/blue or white plumage colour during either season. These and previously published results suggest that structural colour might be sensitive to stress, rather than reduced body condition, during moult.
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Affiliation(s)
- A Peters
- Sexual Signals Group, Max Planck Institute for Ornithology, Vogelwarte Radolfzell, Radolfzell, Germany.
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30
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The carotenoid conundrum: improved nutrition boosts plasma carotenoid levels but not immune benefits of carotenoid supplementation. Oecologia 2011; 166:35-43. [PMID: 21301878 DOI: 10.1007/s00442-011-1921-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2010] [Accepted: 01/12/2011] [Indexed: 10/18/2022]
Abstract
Carotenoids are widely heralded as central to honest signaling due to their dual roles as pigments and antioxidants/immunostimulants. The aim of this study is to test if diet quality and carotenoids alone or in an interaction influence condition, carotenoid availability in plasma and immune responsiveness. Therefore, a diet experiment during the moult of great tits, Parus major, was performed. In a two-way design, we manipulated general quality (digestibility, protein and vitamin content) as well as carotenoid (lutein) content of semi-synthetic diets. Higher quality diet improved individual condition since birds had greater body mass, and to a lesser extent, higher hematocrit. In addition to the expected positive effect of carotenoid supplementation and individual lutein consumption on circulating lutein, there was a positive effect of enhanced diet quality on plasma carotenoid levels. Carotenoid supplementation, but not diet quality, improved the local inflammatory response and maintenance of body mass during a humoral immune reaction. The enhancement of circulating carotenoid levels by improved general quality of the diet or individual condition could provide a testable, mechanistic explanation for the variation in effects of carotenoid supplementation studies.
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Tibbetts EA, Banan M. Advertised quality, caste and food availability influence the survival cost of juvenile hormone in paper wasps. Proc Biol Sci 2010; 277:3461-7. [PMID: 20534614 DOI: 10.1098/rspb.2010.1003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Life-history trade-offs are often hormonally mediated. Here, we provide a comparative perspective on the endocrine basis of life-history trade-offs by examining the invertebrate hormone juvenile hormone (JH). JH is often associated with benefits, including increased dominance and reproductive success. We tested whether JH reduced survival of Polistes dominulus wasps and whether this survival cost was influenced by factors such as advertised quality, food availability, caste and body size. Overall, JH reduced individual survival. Among fed and unfed queens, JH reduced survival in a dose-dependent manner. Among workers, JH had a stronger effect on survival of fed workers than unfed workers. Unfed workers died quickly and body size was the best predictor of survival. Surprisingly, queens and workers treated with JH survived longer when they had signals advertising high quality than when they had signals advertising low quality. The relationship between advertised quality and ability to withstand high levels of JH suggests that there are differential physiological costs associated with ornament elaboration that could play a role in maintaining signal accuracy over evolutionary time. Overall, the convergence of endocrine-mediated costs across diverse systems suggests that endocrine-mediated trade-offs may be an adaptive way to optimize resource allocation rather than a non-adaptive constraint specific to a particular hormone.
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Affiliation(s)
- Elizabeth A Tibbetts
- Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA.
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Huyghe K, Van Oystaeyen A, Pasmans F, Tadić Z, Vanhooydonck B, Van Damme R. Seasonal changes in parasite load and a cellular immune response in a colour polymorphic lizard. Oecologia 2010; 163:867-74. [PMID: 20454978 DOI: 10.1007/s00442-010-1646-9] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2009] [Accepted: 04/15/2010] [Indexed: 11/29/2022]
Abstract
Permanent colour polymorphisms may be maintained by complex interactions between physiological traits (e.g. immunity) and environmental pressures. In this study we investigate morph specific variation in parasite load and cellular immune response (induced by a Phytohaemagglutinin, PHA injection) in a colour polymorphic population of the Dalmatian wall lizard (Podarcis melisellensis), where adult males have bright white, yellow or orange throats and ventral sides. Orange males have larger heads and can bite harder than the others. To examine seasonal effects, analyses were performed at an early and late stage in the reproductive season (May and September). Infection with mites and ticks did not differ among morphs, but was more severe at the end of the reproductive season. Fewer orange individuals were infected with haemogregarines at the end of the season, but white males were always more infected (higher number of haemogregarines in their blood) than other morphs. White and yellow males showed an increased PHA response towards the end of the season, but PHA response decreased in the orange morph. Finally, across all morphs, a relationship was found between ectoparasite load and PHA response. Our study provides indications of alternative life-history strategies among colour morphs and evidence for an up-regulation of the immune function at the end of the reproductive season.
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Affiliation(s)
- Katleen Huyghe
- Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales-CSIC, Calle José Gutiérrez Abascal 2, 28006 Madrid, Spain.
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Tobler M, Hasselquist D, Smith HG, Sandell MI. Short- and long-term consequences of prenatal testosterone for immune function: an experimental study in the zebra finch. Behav Ecol Sociobiol 2009. [DOI: 10.1007/s00265-009-0889-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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