1
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Mourkas E, Valdebenito JO, Marsh H, Hitchings MD, Cooper KK, Parker CT, Székely T, Johansson H, Ellström P, Pascoe B, Waldenström J, Sheppard SK. Proximity to humans is associated with antimicrobial-resistant enteric pathogens in wild bird microbiomes. Curr Biol 2024; 34:3955-3965.e4. [PMID: 39142288 DOI: 10.1016/j.cub.2024.07.059] [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: 02/13/2024] [Revised: 05/21/2024] [Accepted: 07/16/2024] [Indexed: 08/16/2024]
Abstract
Humans are radically altering global ecology, and one of the most apparent human-induced effects is urbanization, where high-density human habitats disrupt long-established ecotones. Changes to these transitional areas between organisms, especially enhanced contact among humans and wild animals, provide new opportunities for the spread of zoonotic pathogens. This poses a serious threat to global public health, but little is known about how habitat disruption impacts cross-species pathogen spread. Here, we investigated variation in the zoonotic enteric pathogen Campylobacter jejuni. The ubiquity of C. jejuni in wild bird gut microbiomes makes it an ideal organism for understanding how host behavior and ecology influence pathogen transition and spread. We analyzed 700 C. jejuni isolate genomes from 30 bird species in eight countries using a scalable generalized linear model approach. Comparing multiple behavioral and ecological traits showed that proximity to human habitation promotes lineage diversity and is associated with antimicrobial-resistant (AMR) strains in natural populations. Specifically, wild birds from urban areas harbored up to three times more C. jejuni genotypes and AMR genes. This study provides novel methodology and much-needed quantitative evidence linking urbanization to gene pool spread and zoonoses.
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Affiliation(s)
- Evangelos Mourkas
- Ineos Oxford Institute, Department of Biology, University of Oxford, 11a Mansfield Road, Oxford OX1 3SZ, UK; Zoonosis Science Centre, Department of Medical Sciences, Uppsala University, Husargatan 3, 751 23 Uppsala, Sweden
| | - José O Valdebenito
- Bird Ecology Lab, Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Independencia 631, 5110566 Valdivia, Chile; Centro de Humedales Río Cruces (CEHUM), Universidad Austral de Chile, Camino Cabo Blanco Alto s/n, 5090000 Valdivia, Chile; HUN-REN-DE Reproductive Strategies Research Group, Department of Evolutionary Zoology and Human Biology, University of Debrecen, Egyetem tér 1, 4032 Debrecen, Hungary; Instituto Milenio Biodiversidad de Ecosistemas Antárticos y Subantárticos (BASE), Las Palmeras 3425, 8320000 Santiago, Chile
| | - Hannah Marsh
- Milner Centre for Evolution, Department of Life Sciences, University of Bath, Claverton Down, Bath BA2 7AY, UK
| | - Matthew D Hitchings
- Institute of Life Science, Swansea University Medical School, Swansea University, Singleton Park, SA2 8PP Swansea, Wales
| | - Kerry K Cooper
- School of Animal and Comparative Biomedical Sciences, University of Arizona, 1117 E. Lowell St., Tucson, AZ 85721, USA
| | - Craig T Parker
- Produce Safety and Microbiology Unit, Western Region Research Center, USDA, Agricultural Research Service, Albany, CA 94710, USA
| | - Tamás Székely
- HUN-REN-DE Reproductive Strategies Research Group, Department of Evolutionary Zoology and Human Biology, University of Debrecen, Egyetem tér 1, 4032 Debrecen, Hungary; Milner Centre for Evolution, Department of Life Sciences, University of Bath, Claverton Down, Bath BA2 7AY, UK
| | - Håkan Johansson
- Centre for Ecology and Evolution in Microbial Model Systems, Linnaeus University, Stuvaregatan 2, 392 31 Kalmar, Sweden
| | - Patrik Ellström
- Zoonosis Science Centre, Department of Medical Sciences, Uppsala University, Husargatan 3, 751 23 Uppsala, Sweden
| | - Ben Pascoe
- Ineos Oxford Institute, Department of Biology, University of Oxford, 11a Mansfield Road, Oxford OX1 3SZ, UK
| | - Jonas Waldenström
- Centre for Ecology and Evolution in Microbial Model Systems, Linnaeus University, Stuvaregatan 2, 392 31 Kalmar, Sweden
| | - Samuel K Sheppard
- Ineos Oxford Institute, Department of Biology, University of Oxford, 11a Mansfield Road, Oxford OX1 3SZ, UK.
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2
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Burke NW, Holwell G. Costs and benefits of polyandry in a sexually cannibalistic mantis. J Evol Biol 2023; 36:412-423. [PMID: 36537353 DOI: 10.1111/jeb.14135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 10/31/2022] [Accepted: 11/16/2022] [Indexed: 12/24/2022]
Abstract
Mating with more than one male often provides direct or indirect benefits to female fitness but can also increase the chance of injury and death. Costs of mating are expected to increase linearly with increasing mating number. But how such costs interact with benefits to determine the net payoff of mating multiply is not well understood. Using the highly cannibalistic Springbok mantis, Miomantis caffra, a species where females are stabbed in the abdomen by males during violent premating struggles that males initiate to avoid being cannibalized, we took an experimental approach to assess the economics of polyandry under the risk of external, male-inflicted injury. We predicted that females that mate multiply would be more likely to show abdominal injuries, have higher prereproductive mortality, produce fewer offspring and be more likely to engage in pre-mating cannibalism to avoid unwanted matings. In line with our predictions, we found that the likelihood of abdominal injury was highest among females that mated at least once, and prereproductive death was highest among females that mated twice or three times. Virgin females completely avoided these costs and produced some offspring parthenogenetically but not enough to provide a net benefit. Although mating was better than not mating, there was no singularly optimal mating number: females that mated once and three times produced similarly high numbers of offspring from the first ootheca, which resulted in an intermediate trough in offspring production at two matings. We also found little evidence that cannibalism was deployed as a mate-avoidance strategy: females consistently attacked and consumed males regardless of how many times they mated or how long they were housed with males. Our results suggest the possibility of two distinct mating strategies in M. caffra, where females either mate at a lower frequency to minimize costs or at a higher frequency to maximize benefits. We discuss possible explanations for this bimodal pattern in offspring production.
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Affiliation(s)
- Nathan W Burke
- School of Biological Sciences, University of Auckland, Auckland, New Zealand.,Institute of Cell and Systems Biology of Animals, University of Hamburg, Hamburg, Germany
| | - Gregory Holwell
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
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3
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Matzke M, Rossi A, Tuni C. Pre- and post-copulatory sexual selection increase offspring quality but impose survival costs to female field crickets. J Evol Biol 2023; 36:296-308. [PMID: 36484616 DOI: 10.1111/jeb.14132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 10/31/2022] [Accepted: 11/09/2022] [Indexed: 12/14/2022]
Abstract
Whether sexual selection increases or decreases fitness is under ongoing debate. Sexual selection operates before and after mating. Yet, the effects of each episode of selection on individual reproductive success remain largely unexplored. We ask how disentangled pre- and post-copulatory sexual selection contribute to fitness of field crickets Gryllus bimaculatus. Treatments allowed exclusively for (i) pre-copulatory selection, with males fighting and courting one female, and the resulting pair breeding monogamously, (ii) post-copulatory selection, with females mating consecutively to multiple males and (iii) relaxed selection, with enforced pair monogamy. While standardizing the number of matings, we estimated a number of fitness traits across treatments and show that females experiencing sexual selection were more likely to reproduce, their offspring hatched sooner, developed faster and had higher body mass at adulthood, but females suffered survival costs. Interestingly, we found no differences in fitness of females or their offspring from pre- and post-copulatory sexual selection treatments. Our findings highlight the potential for sexual selection in enhancing indirect female fitness while concurrently imposing direct survival costs. By potentially outweighing these costs, increased offspring quality could lead to beneficial population-level consequences of sexual selection.
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Affiliation(s)
| | - Aurora Rossi
- Ludwig Maximilian University of Munich, Munich, Germany
| | - Cristina Tuni
- Ludwig Maximilian University of Munich, Munich, Germany
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4
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Cunningham NC, Mitchell RC, Mogilski JK. Which styles of moral reasoning predict apprehension toward consensual non-monogamy? PERSONALITY AND INDIVIDUAL DIFFERENCES 2022. [DOI: 10.1016/j.paid.2022.111732] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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5
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Odewahn R, Wright BR, Czirják GÁ, Higgins DP. Differences in constitutive innate immunity between divergent Australian marsupials. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2022; 132:104399. [PMID: 35307478 DOI: 10.1016/j.dci.2022.104399] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 03/14/2022] [Accepted: 03/15/2022] [Indexed: 06/14/2023]
Abstract
Understanding immunity in wildlife populations is important from both One Health and conservation perspectives. The constitutive innate immune system is the first line of defence against pathogens, and comparisons among taxa can test the impact of evolution and life history on immune function. We investigated serum bacterial killing ability (BKA) of five marsupial species that employ varying life history strategies, demonstrated to influence immunity in other vertebrates. The brushtail possum and eastern grey kangaroo had the greatest BKA, while ringtail possums and koalas had the least. These differences were independent of social structure, captivity status and phylogeny, but were associated with diet and body size. Sex and disease status had no effect on BKA in koalas, however potential for differences between wild and captive koalas warrants further investigation. The current study has provided a foundation for future investigations into how adaptive and innate immunity interact in marsupials from an eco-evolutionary perspective.
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Affiliation(s)
- Rebecca Odewahn
- Sydney School of Veterinary Science, Faculty of Science, University of Sydney, NSW, Australia
| | - Belinda R Wright
- Sydney School of Veterinary Science, Faculty of Science, University of Sydney, NSW, Australia
| | - Gábor Á Czirják
- Department of Wildlife Diseases, Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Straße 17, 10315, Berlin, Germany
| | - Damien P Higgins
- Sydney School of Veterinary Science, Faculty of Science, University of Sydney, NSW, Australia.
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6
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Rigaill L, Vaglio S, Setchell JM, Suda-Hashimoto N, Furuichi T, Garcia C. Chemical cues of identity and reproductive status in Japanese macaques. Am J Primatol 2022; 84:e23411. [PMID: 35757843 DOI: 10.1002/ajp.23411] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 04/26/2022] [Accepted: 05/27/2022] [Indexed: 01/30/2023]
Abstract
Olfactory communication plays an important role in the regulation of socio-sexual interactions in mammals. There is growing evidence that both human and nonhuman primates rely on odors to inform their mating decisions. Nevertheless, studies of primate chemical ecology remain scarce due to the difficulty of obtaining and analyzing samples. We analyzed 67 urine samples from five captive female Japanese macaques (Macaca fuscata) and 30 vaginal swabs from three of these females using gas chromatography-mass spectrometry and examined the relationship between odor (compounds identified, richness, intensity, and diversity) and female identity as well as cycle phase. We found a total of 36 urine compounds of which we identified 31, and 68 vaginal compounds of which we identified 37. Our results suggest that urine and vaginal odor varied more between individuals than within cycle phases. However, we found that within a female cycle, urine samples from similar phases may cluster more than samples from different phases. Our results suggest that female odor may encode information about identity (vaginal and urine odor) and reproductive status (urine odor). The question of how conspecifics use female urine and vaginal odor remains open and could be tested using bioassays. Our results and their interpretation are constrained by our limited sample size and our study design. Nonetheless, our study provides insight into the potential signaling role of female odor in sexual communication in Japanese macaques and contributes to our understanding of how odors may influence mating strategies in primates.
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Affiliation(s)
- Lucie Rigaill
- EthoS (Éthologie animale et humaine), CNRS, Université de Rennes 1, Normandie Université, Rennes, France.,Center for the Evolutionary Origins of Human Behavior, Kyoto University, Inuyama, Japan
| | - Stefano Vaglio
- School of Sciences, University of Wolverhampton, Wolverhampton, UK
| | - Joanna M Setchell
- Department of Anthropology & Behaviour, Ecology and Evolution Research Centre, Durham University, Durham, UK
| | - Naoko Suda-Hashimoto
- Center for the Evolutionary Origins of Human Behavior, Kyoto University, Inuyama, Japan
| | - Takeshi Furuichi
- Center for the Evolutionary Origins of Human Behavior, Kyoto University, Inuyama, Japan
| | - Cécile Garcia
- Eco-anthropologie (EA), Muséum national d'Histoire naturelle, CNRS, Université Paris Cité, Paris, France
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7
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Tepox-Vivar N, Stephenson JF, Guevara-Fiore P. Transmission dynamics of ectoparasitic gyrodactylids (Platyhelminthes, Monogenea): An integrative review. Parasitology 2022; 149:1-13. [PMID: 35481457 DOI: 10.1017/s0031182022000361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Parasite transmission is the ability of pathogens to move between hosts. As a key component of the interaction between hosts and parasites, it has crucial implications for the fitness of both. Here, we review the transmission dynamics of Gyrodactylus species, which are monogenean ectoparasites of teleost fishes and a prominent model for studies of parasite transmission. Particularly, we focus on the most studied host–parasite system within this genus: guppies, Poecilia reticulata, and G. turnbulli/G. bullatarudis. Through an integrative literature examination, we identify the main variables affecting Gyrodactylus spread between hosts, and the potential factors that enhance their transmission. Previous research indicates that Gyrodactylids spread when their current conditions are unsuitable. Transmission depends on abiotic factors like temperature, and biotic variables such as gyrodactylid biology, host heterogeneity, and their interaction. Variation in the degree of social contact between hosts and sexes might also result in distinct dynamics. Our review highlights a lack of mathematical models that could help predict the dynamics of gyrodactylids, and there is also a bias to study only a few species. Future research may usefully focus on how gyrodactylid reproductive traits and host heterogeneity promote transmission and should incorporate the feedbacks between host behaviour and parasite transmission.
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Affiliation(s)
- Natalia Tepox-Vivar
- Maestría en Ciencias Biológicas, Benemérita Universidad Autónoma de Puebla (BUAP), Puebla 72592, Mexico
| | - Jessica F Stephenson
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Palestina Guevara-Fiore
- Facultad de Ciencias Biológicas, Benemérita Universidad Autónoma de Puebla (BUAP), Puebla 72592, Mexico
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8
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Sugianto NA, Heistermann M, Newman C, Macdonald DW, Buesching CD. Alternative reproductive strategies provide a flexible mechanism for assuring mating success in the European badgers (Meles meles): An investigation from hormonal measures. Gen Comp Endocrinol 2021; 310:113823. [PMID: 34044013 DOI: 10.1016/j.ygcen.2021.113823] [Citation(s) in RCA: 3] [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: 12/18/2020] [Revised: 04/19/2021] [Accepted: 05/21/2021] [Indexed: 10/21/2022]
Abstract
Selection-pressures differ with population density, but few studies investigate how this can affect reproductive physiology. European badger (Meles meles) density varies from solitary to group-living across their range, with reported mating periods throughout the entire year to specific seasonal periods. Badger reproduction is evolutionarily distinct, interrupting the direct progression from conception to gestation with delayed implantation (DI), allowing for superfecundation (SF). To establish the tactical mating flexibility afforded by DI*SF, we used cross-sectional population-level seasonal variation of circulating sex-steroids for 97 females from a high-density population. Oestradiol was highest in spring among non-parous females, then lower in summer, and remained low during following seasons, suggesting that the mating period was restricted to just spring. Oestrone was consistently higher than oestradiol; it was elevated in spring, lowest during summer, peaked in autumn, and remained elevated for pregnant females in winter. This suggests that oestrone sustains pre-implanted blastocysts throughout DI. Progesterone was low throughout, except during winter pregnancy, associated with implantation and luteal development. In contrast to multiple mating periods reported by lower-density studies, our oestradiol data suggest that, at high-density, females exhibit only one mating period (congruent with testosterone patterns in males studied previously in this same population). While additional mating periods during DI enhance fertility assurance at low-density, at high-density, we propose that when coitus is frequent, fertilisation is assured, precluding the need for further cycles and associated mating risks. This endocrinologically flexible DI*SF mating strategy likely represents a form of balancing selection, allowing badgers to succeed at a range of regional densities.
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Affiliation(s)
- Nadine Adrianna Sugianto
- Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, Oxford, UK; School of Biosciences, University of Birmingham, Birmingham, UK.
| | - Michael Heistermann
- Endocrinology Laboratory, German Primate Center, Kellnerweg 4, 37077 Göttingen, Germany
| | - Chris Newman
- Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, Oxford, UK; Cook's Lake Farming Forestry and Wildlife Inc (Ecological Consultancy), Queens County, Nova Scotia, Canada
| | - David W Macdonald
- Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, Oxford, UK
| | - Christina D Buesching
- Cook's Lake Farming Forestry and Wildlife Inc (Ecological Consultancy), Queens County, Nova Scotia, Canada; Department of Biology, Irving K. Barber Faculty of Sciences, The University of British Columbia, Kelowna, British Columbia, Canada
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9
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Fear of sex: sexual conflict exposed as avoidance in a parthenogenetic invertebrate. Behav Ecol Sociobiol 2021. [DOI: 10.1007/s00265-021-03054-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Abstract
Males and females often have divergent evolutionary interests, generating sexual conflicts. This is particularly true in organisms that exhibit facultative sexuality, whereby females are capable of reproducing without fitness costs of mating. Here, we provide the first documented evidence with quantitative tracking showing that sex interacts with social context to determine space-use of females, in a pattern resembling predator avoidance. To achieve this, we labelled Daphnia magna with fluorescent nanoparticles and utilized a 3-D tracking platform to record pairs of individuals swimming. The recordings comprised either same-sex or opposite-sex pairings. We found that females swam faster, deeper, more horizontally, and more linearly when exposed to males than when exposed to females. Simultaneously, we found that male behavior did not differ depending on swimming partner and, importantly, we observed no sexual dimorphism in swimming behaviors when swimming with the same sex. Our results suggest that the presence of males in a population has the potential to influence the distribution of individuals, similarly to known threats, such as predation. This highlights that sexual conflict has clear spatial consequences and should be considered in such ecological frameworks, like the Landscape of Fear (LOF) concept. In a broader context, the connection of the evolutionary and social concept of sexual conflict and the ecological concept of LOF may improve our understanding of population dynamics and the spatial and temporal distribution of individuals in natural ecosystems.
Significance statement
Despite the wealth of studies that detail how predators affect their prey’s spatial behaviors, studies on the role of sex and social context on spatial behavior are rare. Addressing this dearth of information, we studied the swimming behaviors of an organism that can reproduce with or without sex, when exposed to an individual of either the same or opposite sex. We found no difference between the sexes in swimming behaviors; however, we revealed that females avoided males by swimming deeper in the water column, reminiscent of the response to predation. Our results highlight that social conflict between the sexes strongly affects the demographics of a population and may therefore have a substantial role in the spatial ecology of organisms in the wild.
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10
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Hernandez J, Hucul C, Reasor E, Smith T, McGlothlin JW, Haak DC, Belden LK, Moore IT. Assessing age, breeding stage, and mating activity as drivers of variation in the reproductive microbiome of female tree swallows. Ecol Evol 2021; 11:11398-11413. [PMID: 34429928 PMCID: PMC8366841 DOI: 10.1002/ece3.7929] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 06/25/2021] [Accepted: 06/29/2021] [Indexed: 11/08/2022] Open
Abstract
Sexually transmitted microbes are hypothesized to influence the evolution of reproductive strategies. Though frequently discussed in this context, our understanding of the reproductive microbiome is quite nascent. Indeed, testing this hypothesis first requires establishing a baseline understanding of the temporal dynamics of the reproductive microbiome and of how individual variation in reproductive behavior and age influence the assembly and maintenance of the reproductive microbiome as a whole. Here, we ask how mating activity, breeding stage, and age influence the reproductive microbiome. We use observational and experimental approaches to explain variation in the cloacal microbiome of free-living, female tree swallows (Tachycineta bicolor). Using microsatellite-based parentage analyses, we determined the number of sires per brood (a proxy for female mating activity). We experimentally increased female sexual activity by administering exogenous 17ß-estradiol. Lastly, we used bacterial 16S rRNA amplicon sequencing to characterize the cloacal microbiome. Neither the number of sires per brood nor the increased sexual activity of females significantly influenced female cloacal microbiome richness or community structure. Female age, however, was positively correlated with cloacal microbiome richness and influenced overall community structure. A hypothesis to explain these patterns is that the effect of sexual activity and the number of mates on variation in the cloacal microbiome manifests over an individual's lifetime. Additionally, we found that cloacal microbiome alpha diversity (Shannon Index, Faith's phylogenetic distance) decreased and community structure shifted between breeding stages. This is one of few studies to document within-individual changes and age-related differences in the cloacal microbiome across successive breeding stages. More broadly, our results contribute to our understanding of the role that host life history and behavior play in shaping the cloacal microbiomes of wild birds.
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Affiliation(s)
| | - Catherine Hucul
- Department of Biological SciencesVirginia TechBlacksburgVAUSA
| | - Emily Reasor
- Department of Biological SciencesVirginia TechBlacksburgVAUSA
| | - Taryn Smith
- Department of Biological SciencesVirginia TechBlacksburgVAUSA
| | | | - David C. Haak
- School of Plant and Environmental SciencesVirginia TechBlacksburgVAUSA
| | - Lisa K. Belden
- Department of Biological SciencesVirginia TechBlacksburgVAUSA
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11
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How do biases in sex ratio and disease characteristics affect the spread of sexually transmitted infections? J Theor Biol 2021; 527:110832. [PMID: 34252402 DOI: 10.1016/j.jtbi.2021.110832] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 05/05/2021] [Accepted: 07/06/2021] [Indexed: 01/05/2023]
Abstract
The epidemiology of sexually transmitted infections (STIs) is inherently linked to host mating dynamics. Studies across many taxa show that adult sex ratio, a major determinant of host mating dynamics, is often skewed - sometimes strongly - toward males or females. However, few predictions exist for the effects of skewed sex ratio on STI epidemiology, and none when coupled with sex biased disease characteristics. Here we use mathematical modelling to examine how interactions between sex ratio and disease characteristics affect STI prevalence in males and females. Notably, we find that while overall disease prevalence peaks at equal sex ratios, prevalence per sex peaks at skewed sex ratios. Furthermore, disease characteristics, sex-biased or not, drive predictable differences in male and female STI prevalence as sex ratio varies, with higher transmission and lower virulence generally increasing differences between the sexes for a given sex ratio. Our work reveals new insights into how STI prevalence in males and females depends on a complex interaction between host population sex ratio and disease characteristics.
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12
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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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13
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Erazo D, Pedersen AB, Gallagher K, Fenton A. Who acquires infection from whom? Estimating herpesvirus transmission rates between wild rodent host groups. Epidemics 2021; 35:100451. [PMID: 33761448 DOI: 10.1016/j.epidem.2021.100451] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 02/10/2021] [Accepted: 03/10/2021] [Indexed: 11/24/2022] Open
Abstract
To date, few studies of parasite epidemiology have investigated 'who acquires infection from whom' in wildlife populations. Nonetheless, identifying routes of disease transmission within a population, and determining the key groups of individuals that drive parasite transmission and maintenance, are fundamental to understanding disease dynamics. Gammaherpesviruses are a widespread group of DNA viruses that infect many vertebrate species, and murine gammaherpesviruses (i.e. MuHV-4) are a standard lab model for studying human herpesviruses, for which much about the pathology and immune response elicited to infection is well understood. However, despite this extensive research effort, primarily in the lab, the transmission route of murine gammaherpesviruses within their natural host populations is not well understood. Here, we aimed to understand wood mouse herpesvirus (WMHV) transmission, by fitting a series of population dynamic models to field data on wood mice naturally infected with WMHV and then estimating transmission parameters within and between demographic groups of the host population. Different models accounted for different combinations of host sex (male/female), age (subadult/adult) and transmission functions (density/frequency-dependent). We found that a density-dependent transmission model incorporating explicit sex groups fitted the data better than all other proposed models. Male-to-male transmission was the highest among all possible combinations of between- and within-sex transmission classes, suggesting that male behaviour is a key factor driving WMHV transmission. Our models also suggest that transmission between sexes, although important, wasn't symmetrical, with infected males playing a significant role in infecting naïve females but not vice versa. Overall this work shows the power of coupling population dynamic models with long-term field data to elucidate otherwise unobservable transmission processes in wild disease systems.
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Affiliation(s)
- Diana Erazo
- Institute of Infection, Veterinary, and Ecological Sciences, University of Liverpool, Liverpool, L69 7ZB, UK.
| | - Amy B Pedersen
- Institute of Evolutionary Biology & Centre for Infection, Immunity and Evolution, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3FL, UK
| | - Kayleigh Gallagher
- Institute of Infection, Veterinary, and Ecological Sciences, University of Liverpool, Liverpool, L69 7ZB, UK
| | - Andy Fenton
- Institute of Infection, Veterinary, and Ecological Sciences, University of Liverpool, Liverpool, L69 7ZB, UK
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14
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Li GY, Zhang ZQ. Sex-specific response to delayed and repeated mating in spider mite Tetranychus urticae. BULLETIN OF ENTOMOLOGICAL RESEARCH 2021; 111:49-56. [PMID: 32517821 DOI: 10.1017/s0007485320000292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Sexual interaction is an important activity that determines the reproductive schedule of organisms and can ultimately influence the fitness traits of both sexes. Although the influence of sexual interaction on the fitness of females has been extensively determined, little is known about the effects on males, which often have different mating strategies and optimal mating regimes from those of females. To understand how mating regimes (timing and frequency) modulate the fitness in both sexes, we used spider mite (Tetranychus urticae) to investigate the influence of delayed mating and repeated mating on the fitness of male and female. For females, the unmated and the delayed mating females outlived those mated immediately after adult emergence. The repeated mating shortened the lifespan of females that mated at 1-day-old, but not that mated 7-day-old. However, no significant variation in lifespan was observed for males across different mating regimes. We found although delayed mating significantly reduced the daily reproductive rate of the females, there was no significant difference in lifetime reproduction of females across treatments because the delayed mating females increased their reproductive lifespan as a compensation. Our study highlighted that the time and frequency of sexual interaction showed a sex-specific consequence on male and female spider mites, indicating that sexual interaction incurs a higher cost to females which have a much lower optimal mating frequency than males.
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Affiliation(s)
- Guang-Yun Li
- Centre for Biodiversity and Biosecurity, School of Biological Sciences, University of Auckland, Auckland, New Zealand
- Manaaki Whenua - Landcare Research, 231 Morrin Road, Auckland1072, New Zealand
| | - Zhi-Qiang Zhang
- Centre for Biodiversity and Biosecurity, School of Biological Sciences, University of Auckland, Auckland, New Zealand
- Manaaki Whenua - Landcare Research, 231 Morrin Road, Auckland1072, New Zealand
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15
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Evolution of infection avoidance in populations affected by sexually transmitted infections. THEOR ECOL-NETH 2021. [DOI: 10.1007/s12080-020-00494-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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16
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Siva-Jothy JA, Vale PF. Dissecting genetic and sex-specific sources of host heterogeneity in pathogen shedding and spread. PLoS Pathog 2021; 17:e1009196. [PMID: 33465160 PMCID: PMC7846003 DOI: 10.1371/journal.ppat.1009196] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2019] [Revised: 01/29/2021] [Accepted: 11/30/2020] [Indexed: 11/18/2022] Open
Abstract
Host heterogeneity in disease transmission is widespread but precisely how different host traits drive this heterogeneity remains poorly understood. Part of the difficulty in linking individual variation to population-scale outcomes is that individual hosts can differ on multiple behavioral, physiological and immunological axes, which will together impact their transmission potential. Moreover, we lack well-characterized, empirical systems that enable the quantification of individual variation in key host traits, while also characterizing genetic or sex-based sources of such variation. Here we used Drosophila melanogaster and Drosophila C Virus as a host-pathogen model system to dissect the genetic and sex-specific sources of variation in multiple host traits that are central to pathogen transmission. Our findings show complex interactions between genetic background, sex, and female mating status accounting for a substantial proportion of variance in lifespan following infection, viral load, virus shedding, and viral load at death. Two notable findings include the interaction between genetic background and sex accounting for nearly 20% of the variance in viral load, and genetic background alone accounting for ~10% of the variance in viral shedding and in lifespan following infection. To understand how variation in these traits could generate heterogeneity in individual pathogen transmission potential, we combined measures of lifespan following infection, virus shedding, and previously published data on fly social aggregation. We found that the interaction between genetic background and sex explained ~12% of the variance in individual transmission potential. Our results highlight the importance of characterising the sources of variation in multiple host traits to understand the drivers of heterogeneity in disease transmission.
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Affiliation(s)
- Jonathon A. Siva-Jothy
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Pedro F. Vale
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Centre for Immunity, Infection and Evolution, University of Edinburgh, Edinburgh, United Kingdom
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17
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Social Systems. Anim Behav 2021. [DOI: 10.1007/978-3-030-82879-0_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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18
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Bornbusch SL, Grebe NM, Lunn S, Southworth CA, Dimac-Stohl K, Drea C. Stable and transient structural variation in lemur vaginal, labial and axillary microbiomes: patterns by species, body site, ovarian hormones and forest access. FEMS Microbiol Ecol 2020; 96:5836713. [PMID: 32401310 DOI: 10.1093/femsec/fiaa090] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 05/12/2020] [Indexed: 01/01/2023] Open
Abstract
Host-associated microbiomes shape and are shaped by myriad processes that ultimately delineate their symbiotic functions. Whereas a host's stable traits, such as its lineage, relate to gross aspects of its microbiome structure, transient factors, such as its varying physiological state, relate to shorter term, structural variation. Our understanding of these relationships in primates derives principally from anthropoid studies and would benefit from a broader, comparative perspective. We thus examined the vaginal, labial and axillary microbiota of captive, female ring-tailed lemurs (Lemur catta) and Coquerel's sifakas (Propithecus coquereli), across an ovarian cycle, to better understand their relation to stable (e.g. species identity/mating system, body site) and transient (e.g. ovarian hormone concentration, forest access) host features. We used 16S amplicon sequencing to determine microbial composition and enzyme-linked immunosorbent assays to measure serum hormone concentrations. We found marked variation in microbiota diversity and community composition between lemur species and their body sites. Across both host species, microbial diversity was significantly correlated with ovarian hormone concentrations: negatively with progesterone and positively with estradiol. The hosts' differential forest access related to the diversity of environmental microbes, particularly in axillary microbiomes. Such transient endogenous and exogenous modulators have potential implications for host reproductive health and behavioral ecology.
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Affiliation(s)
| | - Nicholas M Grebe
- Department of Evolutionary Anthropology, Duke University, Durham, NC 27708, USA
| | - Siera Lunn
- Department of Biology, Duke University, Durham, NC 27708, USA
| | | | - Kristin Dimac-Stohl
- Department of Evolutionary Anthropology, Duke University, Durham, NC 27708, USA
| | - Christine Drea
- Department of Evolutionary Anthropology, Duke University, Durham, NC 27708, USA.,Department of Biology, Duke University, Durham, NC 27708, USA
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19
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Huck M, Di Fiore A, Fernandez-Duque E. Of Apples and Oranges? The Evolution of “Monogamy” in Non-human Primates. Front Ecol Evol 2020. [DOI: 10.3389/fevo.2019.00472] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
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20
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Promiscuity and sex ratio in the terrestrial isopod Armadillidium vulgare and consequences on genetic diversity. Behav Processes 2019; 171:104030. [PMID: 31899276 DOI: 10.1016/j.beproc.2019.104030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 12/03/2019] [Accepted: 12/27/2019] [Indexed: 11/21/2022]
Abstract
In promiscuous mating systems, both males and females mate with several partners. While the benefits of multiple mating are well recognized for males, there are several non-mutually exclusive hypotheses to explain multiple mating for females. Promiscuity is widespread in terrestrial isopods. Here, we placed experimental populations of the terrestrial isopod Armadillidium vulgare under varying sex ratios to manipulate the number of available partners, and better characterise the mating system in this species by performing paternity tests using microsatellite markers. We observed that females usually mate multiply with up to 5 males in a single event of reproduction. A higher number of fathers in broods did not increase brood size nor heterozygosity, but increased allelic richness. Promiscuity seems to be asymmetric in this species, with females being less affected by changes in sex ratio than were males and would be an adaptive mating system maximising the offspring genetic diversity.
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21
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Ashby B. Antagonistic coevolution between hosts and sexually transmitted infections. Evolution 2019; 74:43-56. [PMID: 31732970 PMCID: PMC6973023 DOI: 10.1111/evo.13883] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 09/06/2019] [Accepted: 10/09/2019] [Indexed: 01/13/2023]
Abstract
Sexually transmitted infections (STIs) are predicted to play an important role in the evolution of host mating strategies, and vice versa, yet our understanding of host‐STI coevolution is limited. Previous theoretical work has shown mate choice can evolve to prevent runaway STI virulence evolution in chronic, sterilizing infections. Here, I generalize this theory to examine how a broader range of life‐history traits influence coevolution; specifically, how host preferences for healthy mates and STI virulence coevolve when infections are acute and can cause mortality or sterility, and hosts do not form long‐term sexual partnerships. I show that mate choice reduces both mortality and sterility virulence, with qualitatively different outcomes depending on the mode of virulence, costs associated with mate choice, recovery rates, and host lifespan. For example, fluctuating selection—a key finding in previous work—is most likely when hosts have moderate lifespans, STIs cause sterility and long infections, and costs of mate choice are low. The results reveal new insights into the coevolution of mate choice and STI virulence as different life‐history traits vary, providing increased support for parasite‐mediated sexual selection as a potential driver of host mate choice, and mate choice as a constraint on the evolution of virulence.
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Affiliation(s)
- Ben Ashby
- Department of Mathematical Sciences, University of Bath, Bath, BA2 7AY, United Kingdom
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22
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Morse P, Huffard CL. Tactical Tentacles: New Insights on the Processes of Sexual Selection Among the Cephalopoda. Front Physiol 2019; 10:1035. [PMID: 31496951 PMCID: PMC6712556 DOI: 10.3389/fphys.2019.01035] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 07/29/2019] [Indexed: 01/31/2023] Open
Abstract
The cephalopods (Mollusca: Cephalopoda) are an exceptional class among the invertebrates, characterised by the advanced development of their conditional learning abilities, long-term memories, capacity for rapid colour change and extremely adaptable hydrostatic skeletons. These traits enable cephalopods to occupy diverse marine ecological niches, become successful predators, employ sophisticated predator avoidance behaviours and have complex intraspecific interactions. Where studied, observations of cephalopod mating systems have revealed detailed insights to the life histories and behavioural ecologies of these animals. The reproductive biology of cephalopods is typified by high levels of both male and female promiscuity, alternative mating tactics, long-term sperm storage prior to spawning, and the capacity for intricate visual displays and/or use of a distinct sensory ecology. This review summarises the current understanding of cephalopod reproductive biology, and where investigated, how both pre-copulatory behaviours and post-copulatory fertilisation patterns can influence the processes of sexual selection. Overall, it is concluded that sperm competition and possibly cryptic female choice are likely to be critical determinants of which individuals' alleles get transferred to subsequent generations in cephalopod mating systems. Additionally, it is emphasised that the optimisation of offspring quality and/or fertilisation bias to genetically compatible males are necessary drivers for the proliferation of polyandry observed among cephalopods, and potential methods for testing these hypotheses are proposed within the conclusion of this review. Further gaps within the current knowledge of how sexual selection operates in this group are also highlighted, in the hopes of prompting new directions for research of the distinctive mating systems in this unique lineage.
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Affiliation(s)
- Peter Morse
- Australian Institute of Marine Science, Crawley, WA, Australia.,College of Science and Engineering, James Cook University, Townsville, QLD, Australia
| | - Christine L Huffard
- Monterey Bay Aquarium Research Institute, Moss Landing, CA, United States.,California Academy of Sciences, San Francisco, CA, United States
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23
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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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24
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Lima MT, Andrade ACDSP, Oliveira GP, Nicoli JR, Martins FDS, Kroon EG, Abrahão JS. Virus and microbiota relationships in humans and other mammals: An evolutionary view. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/j.humic.2018.11.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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25
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Males can evolve lower resistance to sexually transmitted infections to infect their mates and thereby increase their own fitness. Evol Ecol 2019. [DOI: 10.1007/s10682-019-09976-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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26
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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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27
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Wardlaw AM, Agrawal AF. Sexual Conflict and Sexually Transmitted Infections (STIs): Coevolution of Sexually Antagonistic Host Traits with an STI. Am Nat 2018; 193:E1-E14. [PMID: 30624111 DOI: 10.1086/700564] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
In many taxa, there is a conflict between the sexes over mating rate. The outcome of sexually antagonistic coevolution depends on the costs of mating and natural selection against sexually antagonistic traits. A sexually transmitted infection (STI) changes the relative strength of these costs. We study the three-way evolutionary interaction among male persistence, female resistance, and STI virulence for two types of STIs: a viability-reducing STI and a reproduction-reducing STI. A viability-reducing STI escalates conflict between the sexes. This leads to increased STI virulence (i.e., full coevolution) if the costs of sexually antagonistic traits occur through viability but not through reproduction. In contrast, a reproduction-reducing STI de-escalates the sexual conflict, but STI virulence does not coevolve in response. We also investigated the establishment probability of STIs under different combinations of evolvability. Successful invasion by a viability-reducing STI becomes less likely if hosts (but not parasites) are evolvable, especially if only the female trait can evolve. A reproduction-reducing STI can almost always invade because it does not kill its host. We discuss how the evolution of host and parasite traits in a system with sexual conflict differs from a system with female mate choice.
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28
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29
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Moss JB, Gerber GP, Schwirian A, Jackson AC, Welch ME. Evidence for dominant males but not choosy females in an insular rock iguana. Behav Ecol 2018. [DOI: 10.1093/beheco/ary131] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Jeanette B Moss
- Biological Sciences Department, Mississippi State University, Mississippi State, MS, USA
| | - Glenn P Gerber
- Institute for Conservation Research, San Diego Zoo Global, Escondido, CA, USA
| | - Aumbriel Schwirian
- Biological Sciences Department, Mississippi State University, Mississippi State, MS, USA
| | - Anna C Jackson
- Biological Sciences Department, Mississippi State University, Mississippi State, MS, USA
| | - Mark E Welch
- Biological Sciences Department, Mississippi State University, Mississippi State, MS, USA
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30
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Impacts of infection avoidance for populations affected by sexually transmitted infections. J Theor Biol 2018; 455:64-74. [PMID: 29981756 DOI: 10.1016/j.jtbi.2018.06.030] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Revised: 06/17/2018] [Accepted: 06/27/2018] [Indexed: 11/22/2022]
Abstract
Sexually transmitted infections are ubiquitous in nature and affect many populations. The key process for their transmission is mating, usually preceded by mate choice. Susceptible individuals may avoid mating with infected individuals to prevent infection provided it is recognizable. We show that accounting for infection avoidance significantly alters host population dynamics. We observe bistability between the disease-free and endemic or disease-induced extinction equilibria, significant abrupt reduction in the host population size and disease-induced host extinction. From the population persistence perspective, the best strategy is either not to avoid mating with the infected individuals, to prevent disease-induced host extinction, or to completely avoid mating with the infected individuals, to prevent pathogen invasion. Increasing sterilization efficiency of the infection leads to lower population sizes and reduced effect of mating avoidance. We also find that the disease-free state is more often attained by populations with strong polyandry, whereas a high-density endemic state is more often observed for populations with strong polygyny, suggesting that polygamy rather than monogamy may be promoted in denser host populations.
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31
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Loo J, Kennington WJ, de Lestang S, How J, Evans JP. High levels of polyandry, but limited evidence for multiple paternity, in wild populations of the western rock lobster ( Panulirus cygnus). Ecol Evol 2018; 8:4525-4533. [PMID: 29760893 PMCID: PMC5938460 DOI: 10.1002/ece3.3985] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Revised: 02/07/2018] [Accepted: 02/09/2018] [Indexed: 01/01/2023] Open
Abstract
Polyandry, where multiple mating by females results in the temporal and spatial overlap of ejaculates from two or more males, is taxonomically widespread and occurs in varying frequencies within and among species. In decapods (crabs, lobsters, crayfish, and prawns), rates of polyandry are likely to be variable, but the extent to which patterns of multiple paternity reflect multiple mating, and thus are shaped by postmating processes that bias fertilization toward one or a subset of mated males, is unclear. Here, we use microsatellite markers to examine the frequency of multiple mating (the presence of spermatophores from two or more males) and patterns of paternity in wild populations of western rock lobster (Panulirus cygnus). Our data confirm that >45% of females had attached spermatophores arising from at least two males (i.e., confirming polyandry), but we found very limited evidence for multiple paternity; among 24 clutches sampled in this study, only two arose from fertilizations by two or more males. Single inferred paternal genotypes accounted for all remaining progeny genotypes in each clutch, including several instances when the mother had been shown to mate with two or more males. These findings highlight the need for further work to understand whether polyandry is adaptive and to uncover the mechanisms underlying postmating paternity biases in this system.
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Affiliation(s)
- Jacqueline Loo
- Centre for Evolutionary Biology School of Biological Sciences The University of Western Australia Crawley WA Australia
| | - Winn Jason Kennington
- Centre for Evolutionary Biology School of Biological Sciences The University of Western Australia Crawley WA Australia
| | - Simon de Lestang
- Western Australian Fisheries and Marine Research Laboratories North Beach WA Australia
| | - Jason How
- Western Australian Fisheries and Marine Research Laboratories North Beach WA Australia
| | - Jonathan P Evans
- Centre for Evolutionary Biology School of Biological Sciences The University of Western Australia Crawley WA Australia
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32
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Morse P, Huffard CL, Meekan MG, McCormick MI, Zenger KR. Mating behaviour and postcopulatory fertilization patterns in the southern blue-ringed octopus, Hapalochlaena maculosa. Anim Behav 2018. [DOI: 10.1016/j.anbehav.2017.12.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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33
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Antonovics J. Transmission dynamics: critical questions and challenges. Philos Trans R Soc Lond B Biol Sci 2017; 372:rstb.2016.0087. [PMID: 28289255 DOI: 10.1098/rstb.2016.0087] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/25/2016] [Indexed: 11/12/2022] Open
Abstract
This article overviews the dynamics of disease transmission in one-host-one-parasite systems. Transmission is the result of interacting host and pathogen processes, encapsulated with the environment in a 'transmission triangle'. Multiple transmission modes and their epidemiological consequences are often not understood because the direct measurement of transmission is difficult. However, its different components can be analysed using nonlinear transmission functions, contact matrices and networks. A particular challenge is to develop such functions for spatially extended systems. This is illustrated for vector transmission where a 'perception kernel' approach is developed that incorporates vector behaviour in response to host spacing. A major challenge is understanding the relative merits of the large number of approaches to quantifying transmission. The evolution of transmission mode itself has been a rather neglected topic, but is important in the context of understanding disease emergence and genetic variation in pathogens. Disease impacts many biological processes such as community stability, the evolution of sex and speciation, yet the importance of different transmission modes in these processes is not understood. Broader approaches and ideas to disease transmission are important in the public health realm for combating newly emerging infections.This article is part of the themed issue 'Opening the black box: re-examining the ecology and evolution of parasite transmission'.
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Affiliation(s)
- Janis Antonovics
- Department of Biology, University of Virginia, Charlottesville, VA 22904, USA
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34
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Al-Shawaf L, Lewis DM, Buss DM. Sex Differences in Disgust: Why Are Women More Easily Disgusted Than Men? EMOTION REVIEW 2017. [DOI: 10.1177/1754073917709940] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Women have consistently higher levels of disgust than men. This sex difference is substantial in magnitude, highly replicable, emerges with diverse assessment methods, and affects a wide array of outcomes—including job selection, mate choice, food aversions, and psychological disorders. Despite the importance of this far-reaching sex difference, sound theoretical explanations have lagged behind the empirical discoveries. In this article, we focus on the evolutionary-functional level of analysis, outlining hypotheses capable of explaining why women have higher levels of disgust than men. We present four hypotheses for sexual disgust and six for pathogen disgust, along with testable predictions. Discussion focuses on additional new hypotheses and on future research capable of adjudicating among these competing, but not mutually exclusive, hypotheses.
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Affiliation(s)
- Laith Al-Shawaf
- Department of Psychology, University of Colorado at Colorado Springs, USA
- College of Life Sciences, Institute for Advanced Study, Germany
| | - David M.G. Lewis
- School of Psychology and Exercise Science, Murdoch University, Australia
| | - David M. Buss
- Department of Psychology, The University of Texas at Austin, USA
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35
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Fuochi V, Li Volti G, Furneri PM. Commentary: Lactobacilli Dominance and Vaginal pH: Why Is the Human Vaginal Microbiome Unique? Front Microbiol 2017; 8:1815. [PMID: 28993762 PMCID: PMC5622189 DOI: 10.3389/fmicb.2017.01815] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 09/06/2017] [Indexed: 12/27/2022] Open
Affiliation(s)
- Virginia Fuochi
- Microbiology Section, Department of Biomedical and Biotechnological Sciences, University of CataniaCatania, Italy
| | - Giovanni Li Volti
- Medical Biochemistry Section, Department of Biomedical and Biotechnological Sciences, Biological Tower, University of CataniaCatania, Italy
| | - Pio Maria Furneri
- Microbiology Section, Department of Biomedical and Biotechnological Sciences, University of CataniaCatania, Italy
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36
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Multiple paternity in the cultured yellow pond turtles ( Mauremys mutica ). Anim Reprod Sci 2017; 183:46-55. [DOI: 10.1016/j.anireprosci.2017.06.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Revised: 05/28/2017] [Accepted: 06/08/2017] [Indexed: 11/21/2022]
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37
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Pandulli-Alonso I, Quaglia A, Albo MJ. Females of a gift-giving spider do not trade sex for food gifts: a consequence of male deception? BMC Evol Biol 2017; 17:112. [PMID: 28506206 PMCID: PMC5433081 DOI: 10.1186/s12862-017-0953-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 04/12/2017] [Indexed: 11/25/2022] Open
Abstract
Background Polyandry is commonly maintained by direct benefits in gift-giving species, so females may remate as an adaptive foraging strategy. However, the assumption of a direct benefit fades in mating systems where male gift-giving behaviour has evolved from offering nutritive to worthless (non-nutritive) items. In the spider Paratrechalea ornata, 70% of gifts in nature are worthless. We therefore predicted female receptivity to be independent of hunger in this species. We exposed poorly-fed and well-fed females to multiple males offering nutritive gifts and well-fed females to males offering worthless gifts. Results Though the treatments strongly affected fecundity, females of all groups had similar number of matings. This confirms that female receptivity is independent of their nutritional state, i.e. polyandry does not prevail as a foraging strategy. Conclusions In the spider Pisaura mirabilis, in which the majority (62%) of gifts in nature are nutritive, female receptivity depends on hunger. We therefore propose that the dependence of female receptivity on hunger state may have evolved in species with predominantly nutritive gifts but is absent in species with predominantly worthless gifts. Electronic supplementary material The online version of this article (doi:10.1186/s12862-017-0953-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Irene Pandulli-Alonso
- Laboratorio de Etología, Ecología y Evolución, Instituto de Investigaciones Biológicas Clemente Estable, Avenida Italia, 3318, Montevideo, Uruguay
| | - Agustín Quaglia
- Laboratorio de Arbovirus-Instituto de Virología "Dr. J. M. Vanella"-Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Maria J Albo
- Laboratorio de Etología, Ecología y Evolución, Instituto de Investigaciones Biológicas Clemente Estable, Avenida Italia, 3318, Montevideo, Uruguay.
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38
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Miller EA, Livermore JA, Alberts SC, Tung J, Archie EA. Ovarian cycling and reproductive state shape the vaginal microbiota in wild baboons. MICROBIOME 2017; 5:8. [PMID: 28103920 PMCID: PMC5248513 DOI: 10.1186/s40168-017-0228-z] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 01/04/2017] [Indexed: 05/04/2023]
Abstract
BACKGROUND The vaginal microbiome is an important site of bacterial-mammalian symbiosis. This symbiosis is currently best characterized for humans, where lactobacilli dominate the microbial community and may help defend women against infectious disease. However, lactobacilli do not dominate the vaginal microbiota of any other mammal studied to date, raising key questions about the forces that shape the vaginal microbiome in non-human mammals. RESULTS We used Illumina sequencing of the bacterial 16S rRNA gene to investigate variation in the taxonomic composition of the vaginal microbiota in 48 baboons (Papio cynocephalus), members of a well-studied wild population in Kenya. Similar to prior studies, we found that the baboon vaginal microbiota was not dominated by lactobacilli. Despite this difference, and similar to humans, reproductive state was the dominant predictor of baboon vaginal microbiota, with pregnancy, postpartum amenorrhea, and ovarian cycling explaining 18% of the variance in community composition. Furthermore, among cycling females, a striking 39% of variance in community composition was explained by ovarian cycle phase, with an especially distinctive microbial community around ovulation. Periovulatory females exhibited the highest relative abundance of lactic acid-producing bacteria compared to any other phase, with a mean relative abundance of 44%. To a lesser extent, sexual behavior, especially a history of shared sexual partners, also predicted vaginal microbial similarity between baboons. CONCLUSIONS Despite striking differences in their dominant microbes, both human and baboon vaginal microbiota exhibit profound changes in composition in response to reproductive state, ovarian cycle phase, and sexual behavior. We found major shifts in composition during ovulation, which may have implications for disease risk and conception success. These findings highlight the need for future studies to account for fine-scale differences in reproductive state, particularly differences between the various phases of the ovarian cycle. Overall, our work contributes to an emerging understanding of the forces that explain intra- and inter-individual variation in the mammalian vaginal microbiome, with particular emphasis on its role in host health and disease risk.
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Affiliation(s)
- Elizabeth A Miller
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA.
| | - Joshua A Livermore
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA
| | - Susan C Alberts
- Institute of Primate Research, National Museums of Kenya, Nairobi, Kenya
- Duke Population Research Institute, Duke University, Durham, NC, USA
| | - Jenny Tung
- Institute of Primate Research, National Museums of Kenya, Nairobi, Kenya
- Department of Evolutionary Anthropology, Duke University, Durham, NC, USA
- Duke Population Research Institute, Duke University, Durham, NC, USA
- Department of Biology, Duke University, Durham, NC, USA
| | - Elizabeth A Archie
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA
- Institute of Primate Research, National Museums of Kenya, Nairobi, Kenya
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Ezenwa VO, Archie EA, Craft ME, Hawley DM, Martin LB, Moore J, White L. Host behaviour-parasite feedback: an essential link between animal behaviour and disease ecology. Proc Biol Sci 2016; 283:rspb.2015.3078. [PMID: 27053751 DOI: 10.1098/rspb.2015.3078] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 03/15/2016] [Indexed: 12/18/2022] Open
Abstract
Animal behaviour and the ecology and evolution of parasites are inextricably linked. For this reason, animal behaviourists and disease ecologists have been interested in the intersection of their respective fields for decades. Despite this interest, most research at the behaviour-disease interface focuses either on how host behaviour affects parasites or how parasites affect behaviour, with little overlap between the two. Yet, the majority of interactions between hosts and parasites are probably reciprocal, such that host behaviour feeds back on parasites and vice versa. Explicitly considering these feedbacks is essential for understanding the complex connections between animal behaviour and parasite ecology and evolution. To illustrate this point, we discuss how host behaviour-parasite feedbacks might operate and explore the consequences of feedback for studies of animal behaviour and parasites. For example, ignoring the feedback of host social structure on parasite dynamics can limit the accuracy of predictions about parasite spread. Likewise, considering feedback in studies of parasites and animal personalities may provide unique insight about the maintenance of variation in personality types. Finally, applying the feedback concept to links between host behaviour and beneficial, rather than pathogenic, microbes may shed new light on transitions between mutualism and parasitism. More generally, accounting for host behaviour-parasite feedbacks can help identify critical gaps in our understanding of how key host behaviours and parasite traits evolve and are maintained.
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Affiliation(s)
- Vanessa O Ezenwa
- Odum School of Ecology and Department of Infectious Diseases, University of Georgia, Athens, GA 30602, USA
| | - Elizabeth A Archie
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA
| | - Meggan E Craft
- Department of Veterinary Population Medicine, University of Minnesota, St. Paul, MN 55108, USA
| | - Dana M Hawley
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - Lynn B Martin
- Department of Integrative Biology, University of South Florida, Tampa, FL 33620, USA
| | - Janice Moore
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Lauren White
- Department of Ecology, Evolution and Behavior, University of Minnesota, St. Paul, MN 55108, USA
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Miller EA, Beasley DE, Dunn RR, Archie EA. Lactobacilli Dominance and Vaginal pH: Why Is the Human Vaginal Microbiome Unique? Front Microbiol 2016; 7:1936. [PMID: 28008325 PMCID: PMC5143676 DOI: 10.3389/fmicb.2016.01936] [Citation(s) in RCA: 202] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 11/17/2016] [Indexed: 01/09/2023] Open
Abstract
The human vaginal microbiome is dominated by bacteria from the genus Lactobacillus, which create an acidic environment thought to protect women against sexually transmitted pathogens and opportunistic infections. Strikingly, lactobacilli dominance appears to be unique to humans; while the relative abundance of lactobacilli in the human vagina is typically >70%, in other mammals lactobacilli rarely comprise more than 1% of vaginal microbiota. Several hypotheses have been proposed to explain humans' unique vaginal microbiota, including humans' distinct reproductive physiology, high risk of STDs, and high risk of microbial complications linked to pregnancy and birth. Here, we test these hypotheses using comparative data on vaginal pH and the relative abundance of lactobacilli in 26 mammalian species and 50 studies (N = 21 mammals for pH and 14 mammals for lactobacilli relative abundance). We found that non-human mammals, like humans, exhibit the lowest vaginal pH during the period of highest estrogen. However, the vaginal pH of non-human mammals is never as low as is typical for humans (median vaginal pH in humans = 4.5; range of pH across all 21 non-human mammals = 5.4-7.8). Contrary to disease and obstetric risk hypotheses, we found no significant relationship between vaginal pH or lactobacilli relative abundance and multiple metrics of STD or birth injury risk (P-values ranged from 0.13 to 0.99). Given the lack of evidence for these hypotheses, we discuss two alternative explanations: the common function hypothesis and a novel hypothesis related to the diet of agricultural humans. Specifically, with regard to diet we propose that high levels of starch in human diets have led to increased levels of glycogen in the vaginal tract, which, in turn, promotes the proliferation of lactobacilli. If true, human diet may have paved the way for a novel, protective microbiome in human vaginal tracts. Overall, our results highlight the need for continuing research on non-human vaginal microbial communities and the importance of investigating both the physiological mechanisms and the broad evolutionary processes underlying human lactobacilli dominance.
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Affiliation(s)
- Elizabeth A Miller
- Department of Biological Sciences, University of Notre Dame Notre Dame, IN, USA
| | - DeAnna E Beasley
- Department of Biology, Geology and Environmental Science, University of Tennessee at Chattanooga Chattanooga, TN, USA
| | - Robert R Dunn
- Department of Applied Ecology, North Carolina State UniversityRaleigh, NC, USA; Center for Macroecology, Evolution and Climate, Natural History Museum of Denmark, University of CopenhagenCopenhagen, Denmark
| | - Elizabeth A Archie
- Department of Biological Sciences, University of Notre DameNotre Dame, IN, USA; Institute of Primate Research, National Museums of KenyaNairobi, Kenya
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Valette V, Durand S, Bech N, Grandjean F, Beltran-Bech S. Multiple paternity in a wild population of Armadillidium vulgare
: influence of infection with Wolbachia
? J Evol Biol 2016; 30:235-243. [DOI: 10.1111/jeb.13009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 10/31/2016] [Accepted: 11/01/2016] [Indexed: 02/06/2023]
Affiliation(s)
- V. Valette
- Laboratoire Ecologie et Biologie des Interactions; UMR CNRS 7267; Equipe ‘Ecologie, Evolution, Symbiose’; Université de Poitiers; Poitiers France
| | - S. Durand
- Laboratoire Ecologie et Biologie des Interactions; UMR CNRS 7267; Equipe ‘Ecologie, Evolution, Symbiose’; Université de Poitiers; Poitiers France
| | - N. Bech
- Laboratoire Ecologie et Biologie des Interactions; UMR CNRS 7267; Equipe ‘Ecologie, Evolution, Symbiose’; Université de Poitiers; Poitiers France
| | - F. Grandjean
- Laboratoire Ecologie et Biologie des Interactions; UMR CNRS 7267; Equipe ‘Ecologie, Evolution, Symbiose’; Université de Poitiers; Poitiers France
| | - S. Beltran-Bech
- Laboratoire Ecologie et Biologie des Interactions; UMR CNRS 7267; Equipe ‘Ecologie, Evolution, Symbiose’; Université de Poitiers; Poitiers France
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Perry JC, Joag R, Hosken DJ, Wedell N, Radwan J, Wigby S. Experimental evolution under hyper-promiscuity in Drosophila melanogaster. BMC Evol Biol 2016; 16:131. [PMID: 27311887 PMCID: PMC4910217 DOI: 10.1186/s12862-016-0699-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 06/05/2016] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND The number of partners that individuals mate with over their lifetime is a defining feature of mating systems, and variation in mate number is thought to be a major driver of sexual evolution. Although previous research has investigated the evolutionary consequences of reductions in the number of mates, we know little about the costs and benefits of increased numbers of mates. Here, we use a genetic manipulation of mating frequency in Drosophila melanogaster to create a novel, highly promiscuous mating system. We generated D. melanogaster populations in which flies were deficient for the sex peptide receptor (SPR) gene - resulting in SPR- females that mated more frequently - and genetically-matched control populations, and allowed them to evolve for 55 generations. At several time-points during this experimental evolution, we assayed behavioural, morphological and transcriptional reproductive phenotypes expected to evolve in response to increased population mating frequencies. RESULTS We found that males from the high mating frequency SPR- populations evolved decreased ability to inhibit the receptivity of their mates and decreased copulation duration, in line with predictions of decreased per-mating investment with increased sperm competition. Unexpectedly, SPR- population males also evolved weakly increased sex peptide (SP) gene expression. Males from SPR- populations initially (i.e., before experimental evolution) exhibited more frequent courtship and faster time until mating relative to controls, but over evolutionary time these differences diminished or reversed. CONCLUSIONS In response to experimentally increased mating frequency, SPR- males evolved behavioural responses consistent with decreased male post-copulatory investment at each mating and decreased overall pre-copulatory performance. The trend towards increased SP gene expression might plausibly relate to functional differences in the two domains of the SP protein. Our study highlights the utility of genetic manipulations of animal social and sexual environments coupled with experimental evolution.
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Affiliation(s)
- Jennifer C Perry
- Edward Grey Institute, Department of Zoology, University of Oxford, Oxford, UK. .,Jesus College, University of Oxford, Oxford, UK.
| | - Richa Joag
- University of Exeter, Penryn, UK.,Institute of Environmental Sciences, Jagiellonian University, Kraków, Poland
| | | | | | - Jacek Radwan
- Institute of Environmental Sciences, Jagiellonian University, Kraków, Poland
| | - Stuart Wigby
- Edward Grey Institute, Department of Zoology, University of Oxford, Oxford, UK
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Nunn CL, Craft ME, Gillespie TR, Schaller M, Kappeler PM. The sociality-health-fitness nexus: synthesis, conclusions and future directions. Philos Trans R Soc Lond B Biol Sci 2016; 370:rstb.2014.0115. [PMID: 25870401 DOI: 10.1098/rstb.2014.0115] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
This theme issue has highlighted the links between sociality, health and fitness in a broad range of organisms, and with approaches that include field and captive studies of animals, comparative and meta-analyses, theoretical modelling and clinical and psychological studies of humans. In this concluding chapter, we synthesize the results of these diverse studies into some of the key concepts discussed in this issue, focusing on risks of infectious disease through social contact, the effects of competition in groups on susceptibility to disease, and the integration of sociality into research on life-history trade-offs. Interestingly, the studies in this issue both support pre-existing hypotheses, and in other ways challenge those hypotheses. We focus on unexpected results, including a lack of association between ectoparasites and fitness and weak results from a meta-analysis of the links between dominance rank and immune function, and place these results in a broader context. We also review relevant topics that were not covered fully in this theme issue, including self-medication and sickness behaviours, society-level defences against infectious disease, sexual selection, evolutionary medicine, implications for conservation biology and selective pressures on parasite traits. We conclude by identifying general open questions to stimulate and guide future research on the links between sociality, health and fitness.
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Affiliation(s)
- Charles L Nunn
- Department of Evolutionary Anthropology, Duke University, Box 90383, Durham, NC 27708, USA Duke Global Health Institute, Duke University, 310 Trent Drive, Durham, NC 27710, USA
| | - Meggan E Craft
- Department of Veterinary Population Medicine, University of Minnesota, St Paul, MN 55108, USA
| | - Thomas R Gillespie
- Department of Environmental Sciences and Program in Population Biology, Ecology and Evolution, Emory University, Atlanta, GA 30322, USA Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - Mark Schaller
- Department of Psychology, University of British Columbia, 2136 West Mall, Vancouver, British Columbia, Canada V6T1Z4
| | - Peter M Kappeler
- Behavioral Ecology and Sociobiology Unit, German Primate Center, Göttingen, Germany Department of Sociobiology/Anthropology, University of Göttingen, Göttingen, Germany
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44
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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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45
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Egan AL, Hook KA, Reeve HK, Iyengar VK. Polyandrous females provide sons with more competitive sperm: Support for the sexy-sperm hypothesis in the rattlebox moth (Utetheisa ornatrix). Evolution 2015; 70:72-81. [DOI: 10.1111/evo.12829] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2015] [Accepted: 11/19/2015] [Indexed: 11/27/2022]
Affiliation(s)
- Andrea L. Egan
- Department of Biology; Villanova University; Villanova Pennsylvania 19085
| | - Kristin A. Hook
- Department of Neurobiology and Behavior; Cornell University; Ithaca Pennsylvania 14853
| | - H. Kern Reeve
- Department of Neurobiology and Behavior; Cornell University; Ithaca Pennsylvania 14853
| | - Vikram K. Iyengar
- Department of Biology; Villanova University; Villanova Pennsylvania 19085
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Abstract
Parasites are thought to play an important role in sexual selection and the evolution of mating strategies, which in turn are likely to be critical to the transmission and therefore the evolution of parasites. Despite this clear interdependence we have little understanding of parasite-mediated sexual selection in the context of reciprocal parasite evolution. Here we develop a general coevolutionary model between host mate preference and the virulence of a sexually transmitted parasite. We show when the characteristics of both the host and parasite lead to coevolutionarily stable strategies or runaway selection, and when coevolutionary cycling between high and low levels of host mate choosiness and virulence is possible. A prominent argument against parasites being involved in sexual selection is that they should evolve to become less virulent when transmission depends on host mating success. The present study, however, demonstrates that coevolution can maintain stable host mate choosiness and parasite virulence or indeed coevolutionary cycling of both traits. We predict that choosiness should vary inversely with parasite virulence and that both relatively long and short life spans select against choosy behavior in the host. The model also reveals that hosts can evolve different behavioral responses from the same initial conditions, which highlights difficulties in using comparative analysis to detect parasite-mediated sexual selection. Taken as a whole, our results emphasize the importance of viewing parasite-mediated sexual selection in the context of coevolution.
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Pastok D, Atkinson D, Hurst GD. Assessing the impact of male-killing bacteria on the spread of a sexually transmitted infection. Anim Behav 2015. [DOI: 10.1016/j.anbehav.2015.06.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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48
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McLeod DV, Day T. Sexually transmitted infection and the evolution of serial monogamy. Proc Biol Sci 2015; 281:20141726. [PMID: 25320174 DOI: 10.1098/rspb.2014.1726] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The selective forces shaping mating systems have long been of interest to biologists. One particular selective pressure that has received comparatively little attention is sexually transmitted infections (STIs). While it has been hypothesized that STIs could drive the evolutionary emergence of monogamy, there is little theoretical support. Here we use an evolutionary invasion analysis to determine what aspects of pathogen virulence and transmission are necessary for serial monogamy to evolve in a promiscuous population. We derive a biologically intuitive invasion condition in terms of population-specific quantities. From this condition, we obtain two main results. First, when pathogen virulence causes mortality rather than sterility, monogamy is more likely to evolve. Second, we find that at intermediate pathogen transmission rates, monogamy is the most selectively advantageous, whereas at high- and low-transmission rates, monogamy is generally selected against. As a result, it is possible for a pathogen to be highly virulent, yet for promiscuity to persist.
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Affiliation(s)
- David V McLeod
- Department of Mathematics and Statistics, Queen's University, 99 University Ave Kingston, Ontario, Canada K7L 3N6
| | - Troy Day
- Department of Mathematics and Statistics, Queen's University, 99 University Ave Kingston, Ontario, Canada K7L 3N6
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Abstract
In sexual reproduction different types of symbiotic relationships between insects and microbes have become established. For example, some bacteria have evolved almost exclusive vertical transmission and even define the compatibility of insect mating partners. Many strictly sexually transmitted diseases have also been described in insects. Apart from such rather specific relationships the role of opportunistic infections in the reproductive process has been widely neglected. Opportunistic microbes transmitted passively during mating might impose an energetic cost, as the immune system will need to be alert and will use resources to fight potential intruders. Through mating wounds and contaminated reproductive organs opportunistic microbes might be transferred to mating partners and even enter the body cavity. Females as the "receiving" sex are particularly likely to have evolved adaptations to avoid or reduce opportunistic infections. Males of several species show highly complex seminal fluids, which as well as containing components that influence a males' fertilization success, also possess antimicrobial substances. The role of antimicrobials in the reproductive process is not well understood. Some evidence hints at the protection of sperm against microbes, indicating a role for natural selection in shaping the evolution of reproductive traits. By highlighting the potential importance of microbes in sexual selection and their role in reproduction in general I will make a case for studies in sexual selection, especially the ones investigating postcopulatory processes, that should incorporate environmental, as well as genotypic variation, in reproductive traits.
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Affiliation(s)
- Oliver Otti
- Animal Population Ecology, Animal Ecology I, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Universitätsstrasse, 30, 95440, Bayreuth, Germany
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Ortíz-Jiménez I, Cueva del Castillo R. Nuptial gifts and female fecundity in the neotropical katydid Conocephalus ictus (Orthoptera: Tettigonidae). INSECT SCIENCE 2015; 22:106-110. [PMID: 24431289 DOI: 10.1111/1744-7917.12105] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 12/30/2012] [Indexed: 06/03/2023]
Abstract
In general, female fitness is greatly increased in gift-giving insects. In katydids, this nuptial gift consists of a gelatinous mass produced by accessory glands: the spermatophylax, which is attached to the ampulla. During mating, males of the neotropical katydid Conocephalus ictus transfer a spermatophylax that is ingested by the females. Fecundity, egg-laying rate and longevity were higher in females that consumed the spermatophylax than in those that did not. Also, female receptivity turned off after mating. Females actively rejected other males by hitting them with their forelegs and moving away. Their refractory period lasted as long as 17 d. Only a few females accepted a 2nd mating and died a few days later. In C. ictus, spermatophylax consumption can be beneficial for both males and females. On one hand, the compounds in the spermatophylax or the ejaculate could prevent or delay females from copulating with rivals, thus avoiding sperm competition. On the other hand, such compounds can improve the females' opportunity to increase their lifespan and fecundity. Moreover, a rise in egg-laying rate may lower the risk of female prereproductive death caused by rapid oviposition. In any case, the boost in female egg laying might also be beneficial for males because their number of offspring increases.
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Affiliation(s)
- Isabel Ortíz-Jiménez
- Laboratorio de Ecología, UBIPRO, UNAM, FES Iztacala, México, Edo. México, México
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