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Wojczulanis-Jakubas K, Hoover B, Jakubas D, Fort J, Grémillet D, Gavrilo M, Zielińska S, Zagalska-Neubauer M. Diversity of major histocompatibility complex of II B gene and mate choice in a monogamous and long-lived seabird, the Little Auk (Alle alle). PLoS One 2024; 19:e0304275. [PMID: 38865310 PMCID: PMC11168636 DOI: 10.1371/journal.pone.0304275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 05/09/2024] [Indexed: 06/14/2024] Open
Abstract
The major histocompatibility complex (MHC) plays a key role in the adaptive immune system of vertebrates, and is known to influence mate choice in many species. In birds, the MHC has been extensively examined but mainly in galliforms and passerines while other taxa that represent specific ecological and evolutionary life-histories, like seabirds, are underexamined. Here, we characterized diversity of MHC Class II B exon 2 in a colonial pelagic seabird, the Little Auk (or Dovekie Alle alle). We further examined whether MHC variation could be maintained through balancing selection and disassortative mating. We found high polymorphism at the genotyped MHC fragment, characterizing 99 distinct alleles across 140 individuals from three populations. The alleles frequencies exhibited a similar skewed distribution in both sexes, with the four most commonly occurring alleles representing approximately 35% of allelic variation. The results of a Bayesian site-by-site selection analysis suggest evidence of balancing selection and no direct evidence for MHC-dependent disassortative mating preferences in the Little Auk. The latter result might be attributed to the high overall polymorphism of the examined fragment, which itself may be maintained by the large population size of the species.
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Affiliation(s)
| | - Brian Hoover
- Farallon Institute, Petaluma, California, United States of America
| | - Dariusz Jakubas
- Department of Vertebrate Ecology and Zoology, Faculty of Biology, University of Gdansk, Gdansk, Poland
| | - Jérôme Fort
- Littoral, Environnement et Sociétés (LIENSs), UMR 7266 CNRS – La Rochelle University, 17000 La Rochelle, France
| | - David Grémillet
- Excellence Chair Nouvelle Aquitaine - CEBC UMR 7372 CNRS, La Rochelle Université, Villiers-en-Bois, France & FitzPatrick Institute of African Ornithology, University of Cape Town, Rondebosch, South Africa
| | | | - Sylwia Zielińska
- Department of Molecular Biology, Faculty of Biology, University of Gdansk, Gdansk, Poland
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Rekdal SL, Anmarkrud JA, Lifjeld JT, Johnsen A. Do female bluethroats without extra-pair offspring have more MHC-compatible social mates? Behav Ecol Sociobiol 2023. [DOI: 10.1007/s00265-023-03311-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
Abstract
Abstract
Genes of the major histocompatibility complex (MHC) are crucial for adaptive immunity in jawed vertebrates, and theory predicts that there should be mate choice for optimizing MHC constitution in the offspring. In a previous study, we demonstrated a non-random female choice of extra-pair males in the bluethroat (Luscinia svecica), yielding offspring that was closer to an intermediate MHC class II (MHCII) allele count than their within-pair halfsiblings. The present study tests whether social pairs with only within-pair young (WPY) in their brood, in the same study population, had a combined MHC-constitution closer to a presumed intermediate optimum, than social pairs with extra-pair young (EPY), with a corresponding pattern in their offspring. As expected, we found that WPY from pure WPY-broods were more MHC-optimal than WPY from mixed broods, but only in broods of young (second year) males. Correspondingly, there was a tendency for social pairs with only WPY in their brood to be more MHC-compatible than social pairs with EPY in their brood, when the male was young. Older bluethroat males have considerably larger testes than young males, and their higher sperm competitiveness could help them secure paternity in their own brood, also when they are not MHC-compatible. In other words, in the sexual conflict over paternity, females may be more likely to realise their preference for a MHC-compatible mate when paired to a young male. As a possible fitness indicator, immune responsiveness to an injected antigen (PHA) was elevated for offspring closer to “the golden mean” in MHCII allele count.
Significance statement
This study contributes to our understanding of MHC-based mate choice in extra-pair mating systems, by showing that female bluethroats (Luscinia svecica) with an MHCII-compatible social mate tend to have no extra-pair young in their brood, but only when the social male is young. This elucidates a possible sexual conflict, in which older social males are able to override female preferences and prevent other males from gaining paternity in their brood through higher sperm production. Studying systems in which extra-pair paternity occurs offers an insight into the genetic benefits of mate choice, as extra-pair males, in contrast to social males, generally contribute only sperm. Further, the strict and thorough genotyping scheme applied in this study enabled us to demonstrate a preference for “the golden mean” in MHC-diversity in a species with one of the highest MHC class II-diversity known to date.
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Amo L, Amo de Paz G, Kabbert J, Machordom A. House sparrows do not exhibit a preference for the scent of potential partners with different MHC-I diversity and genetic distances. PLoS One 2022; 17:e0278892. [PMID: 36542616 PMCID: PMC9770374 DOI: 10.1371/journal.pone.0278892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 11/23/2022] [Indexed: 12/24/2022] Open
Abstract
MHC genes play a fundamental role in immune recognition of pathogens and parasites. Therefore, females may increase offspring heterozygosity and genetic diversity by selecting males with genetically compatible or heterozygous MHC. In birds, several studies suggest that MHC genes play a role in mate choice, and recent evidence suggests that olfaction may play a role in the MHC-II discrimination. However, whether olfaction is involved in MHC-I discrimination in birds remains unknown. Previous studies indicate that house sparrow females with low allelic diversity prefer males with higher diversity in MHC-I alleles. Here, we directly explored whether female and male house sparrows (Passer domesticus) could estimate by scent MHC-I diversity and/or dissimilarity of potential partners. Our results show that neither females nor males exhibit a preference related to MHC-I diversity or dissimilarity of potential partners, suggesting that MHC-I is not detected through olfaction. Further studies are needed to understand the mechanisms responsible for mate discrimination based on MHC-I in birds.
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Affiliation(s)
- Luisa Amo
- Departamento de Ecología Evolutiva, Museo Nacional de Ciencias Naturales (MNCN-CSIC), Madrid, Spain
- Area of Biodiversity and Conservation, Universidad Rey Juan Carlos, Móstoles, Spain
- * E-mail:
| | - Guillermo Amo de Paz
- Departamento de Farmacología, Farmacognosia y Botánica, Universidad Complutense de Madrid (UCM), Madrid, Spain
| | - Johanna Kabbert
- Department of Animal Behaviour, Bielefeld University, Bielefeld, Germany
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Annie Machordom
- Departamento de Biodiversidad y Biología Evolutiva, Museo Nacional de Ciencias Naturales (MNCN-CSIC), Madrid, Spain
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Petersen RM, Bergey CM, Roos C, Higham JP. Relationship between genome-wide and MHC class I and II genetic diversity and complementarity in a nonhuman primate. Ecol Evol 2022; 12:e9346. [PMID: 36311412 PMCID: PMC9596323 DOI: 10.1002/ece3.9346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 08/22/2022] [Accepted: 08/25/2022] [Indexed: 11/10/2022] Open
Abstract
Although mate choice is expected to favor partners with advantageous genetic properties, the relative importance of genome‐wide characteristics, such as overall heterozygosity or kinship, versus specific loci, is unknown. To disentangle genome‐wide and locus‐specific targets of mate choice, we must first understand congruence in global and local variation within the same individual. This study compares genetic diversity, both absolute and relative to other individuals (i.e., complementarity), assessed across the genome to that found at the major histocompatibility complex (MHC), a hyper‐variable gene family integral to immune system function and implicated in mate choice across species. Using DNA from 22 captive olive baboons (Papio anubis), we conducted double digest restriction site‐associated DNA sequencing to estimate genome‐wide heterozygosity and kinship, and sequenced two class I and two class II MHC loci. We found that genome‐wide diversity was not associated with MHC diversity, and that diversity at class I MHC loci was not correlated with diversity at class II loci. Additionally, kinship was a significant predictor of the number of MHC alleles shared between dyads at class II loci. Our results provide further evidence of the strong selective pressures maintaining genetic diversity at the MHC in comparison to other randomly selected sites throughout the genome. Furthermore, our results indicate that class II MHC disassortative mate choice may mediate inbreeding avoidance in this population. Our study suggests that mate choice favoring genome‐wide genetic diversity is not always synonymous with mate choice favoring MHC diversity, and highlights the importance of controlling for kinship when investigating MHC‐associated mate choice.
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Affiliation(s)
- Rachel M. Petersen
- Department of AnthropologyNew York UniversityNew YorkNew YorkUSA,New York Consortium in Evolutionary PrimatologyNew YorkNew YorkUSA
| | - Christina M. Bergey
- Department of Genetics and the Human Genetics Institute of New JerseyRutgers UniversityPiscatawayNew JerseyUSA
| | - Christian Roos
- Gene Bank of Primates and Primate Genetics LaboratoryGerman Primate CenterLeibniz Institute for Primate ResearchGöttingenGermany
| | - James P. Higham
- Department of AnthropologyNew York UniversityNew YorkNew YorkUSA,New York Consortium in Evolutionary PrimatologyNew YorkNew YorkUSA
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5
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A Review of Suggested Mechanisms of MHC Odor Signaling. BIOLOGY 2022; 11:biology11081187. [PMID: 36009814 PMCID: PMC9405088 DOI: 10.3390/biology11081187] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 07/26/2022] [Accepted: 08/04/2022] [Indexed: 11/23/2022]
Abstract
Simple Summary Immune genes of the vertebrate MHC vary among individuals. Each individual collection is optimally diverse to provide resistance against some infectious diseases but not too diverse to cause autoimmune diseases. MHC-dependent mate choice aims for optimally complementary MHC alleles. Each potential partner signals through body odor his/her MHC alleles. Identifying the signal molecules was a long-lasting puzzle solved only recently after many deviations as described. Commensal microbiota which are controlled by the individual MHC genes differ among individuals. They were suspected repeatedly to provide the signal, though mice raised germ-free could still smell MHC genes. Carrier hypotheses came in various versions, centered around the specificity of each MHC molecule for binding peptides from diseases, shown to T lymphocytes to induce the immune response. Volatiles of various origins were suggested to fill the place of the peptide and thus reflect the identity of the MHC molecule. Finally, the bound peptides themselves were identified as the sought info-chemicals. Synthesized peptides affect mate choice as predicted. Specific olfactory neurons were shown to react to these peptides but only to the anchors that define the binding specificity. Even eggs choose sperm to produce offspring with optimal MHC, though the signaling pathway needs further research. Abstract Although an individual’s mix of MHC immune genes determines its resistance, finding MHC-dependent mate choice occurred by accident in inbred mice. Inbred mice prefer MHC dissimilar mates, even when the choice was restricted to urine. It took decades to find the info-chemicals, which have to be as polymorphic as the MHC. Microbiota were suggested repeatedly as the origin of the odor signal though germ-free mice maintained normal preference. Different versions of the ‘carrier hypothesis’ suggested MHC molecules carry volatiles after the bound peptide is released. Theory predicted an optimal individual MHC diversity to maximize resistance. The optimally complementary mate should be and is preferred as several studies show. Thus, the odor signal needs to transmit the exact information of the sender’s MHC alleles, as do MHC ligand peptides but not microbiota. The ‘MHC peptide hypothesis’ assumes that olfactory perception of the peptide ligand provides information about the MHC protein in a key-lock fashion. Olfactory neurons react only to the anchors of synthesized MHC peptides, which reflect the binding MHC molecule’s identity. Synthesized peptides supplemented to a male’s signal affect choice in the predicted way, however, not when anchors are mutated. Also, the human brain detects smelled synthesized self-peptides as such. After mate choice, the lottery of meiosis of randomly paired oocyte and sperm haplotypes would often produce MHC non-optimal offspring. In sticklebacks, eggs select MHC-compatible sperm, thus prefer the best combination close to the population optimum.
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Undin M, Castro I. Predicting breeding systems to guide conservation strategies: A kiwi example. Ethology 2022. [DOI: 10.1111/eth.13286] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Malin Undin
- Department of Natural Sciences Mid Sweden University Sundsvall Sweden
- Wildlife and Ecology Group, School of Agriculture and Environment Massey University Palmerston North New Zealand
| | - Isabel Castro
- Wildlife and Ecology Group, School of Agriculture and Environment Massey University Palmerston North New Zealand
- Wildbase Research Massey University Palmerston North New Zealand
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7
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Mancilla-Morales MD, Velarde E, Contreras-Rodríguez A, Gómez-Lunar Z, Rosas-Rodríguez JA, Heras J, Soñanez-Organis JG, Ruiz EA. Characterization, Selection, and Trans-Species Polymorphism in the MHC Class II of Heermann’s Gull (Charadriiformes). Genes (Basel) 2022; 13:genes13050917. [PMID: 35627302 PMCID: PMC9140796 DOI: 10.3390/genes13050917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 05/15/2022] [Accepted: 05/17/2022] [Indexed: 11/16/2022] Open
Abstract
The major histocompatibility complex (MHC) enables vertebrates to cope with pathogens and maintain healthy populations, thus making it a unique set of loci for addressing ecology and evolutionary biology questions. The aim of our study was to examine the variability of Heermann’s Gull MHC class II (MHCIIB) and compare these loci with other Charadriiformes. Fifty-nine MHCIIB haplotypes were recovered from sixty-eight Heermann’s Gulls by cloning, of them, twelve were identified as putative true alleles, forty-five as unique alleles, and two as pseudogenes. Intra and interspecific relationships indicated at least two loci in Heermann’s Gull MHCIIB and trans-species polymorphism among Charadriiformes (coinciding with the documented evidence of two ancient avian MHCIIB lineages, except in the Charadriidae family). Additionally, sites under diversifying selection revealed a better match with peptide-binding sites inferred in birds than those described in humans. Despite the negative anthropogenic activity reported on Isla Rasa, Heermann’s Gull showed MHCIIB variability consistent with population expansion, possibly due to a sudden growth following conservation efforts. Duplication must play an essential role in shaping Charadriiformes MHCIIB variability, buffering selective pressures through balancing selection. These findings suggest that MHC copy number and protected islands can contribute to seabird conservation.
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Affiliation(s)
- Misael Daniel Mancilla-Morales
- Departamento de Zoología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Prolongación de Carpio y Plan de Ayala s/n, Col. Santo Tomás, Ciudad de Mexico CP 11340, Mexico
- Correspondence: (M.D.M.-M.); (J.G.S.-O.); (E.A.R.)
| | - Enriqueta Velarde
- Instituto de Ciencias Marinas y Pesquerías, Universidad Veracruzana, Hidalgo 617, Colonia Río Jamapa, Boca del Rio, Veracruz CP 94290, Mexico;
| | - Araceli Contreras-Rodríguez
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Prolongación de Carpio y Plan de Ayala s/n, Col. Santo Tomás, Ciudad de Mexico CP 11340, Mexico; (A.C.-R.); (Z.G.-L.)
| | - Zulema Gómez-Lunar
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Prolongación de Carpio y Plan de Ayala s/n, Col. Santo Tomás, Ciudad de Mexico CP 11340, Mexico; (A.C.-R.); (Z.G.-L.)
| | - Jesús A. Rosas-Rodríguez
- Departamento de Ciencias Químico-Biológicas y Agropecuarias, Universidad de Sonora, Lázaro Cárdenas del Río No. 100, Francisco Villa, Navojoa CP 85880, Mexico;
| | - Joseph Heras
- Departament of Biology, California State University, San Bernardino, 5500 University Parkway, San Bernardino, CA 92407, USA;
| | - José G. Soñanez-Organis
- Departamento de Ciencias Químico-Biológicas y Agropecuarias, Universidad de Sonora, Lázaro Cárdenas del Río No. 100, Francisco Villa, Navojoa CP 85880, Mexico;
- Correspondence: (M.D.M.-M.); (J.G.S.-O.); (E.A.R.)
| | - Enrico A. Ruiz
- Departamento de Zoología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Prolongación de Carpio y Plan de Ayala s/n, Col. Santo Tomás, Ciudad de Mexico CP 11340, Mexico
- Correspondence: (M.D.M.-M.); (J.G.S.-O.); (E.A.R.)
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8
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Cuevas-Caballé C, Ferrer Obiol J, Vizueta J, Genovart M, Gonzalez-Solís J, Riutort M, Rozas J. The First Genome of the Balearic Shearwater (Puffinus mauretanicus) Provides a Valuable Resource for Conservation Genomics and Sheds Light on Adaptation to a Pelagic lifestyle. Genome Biol Evol 2022; 14:evac067. [PMID: 35524941 PMCID: PMC9117697 DOI: 10.1093/gbe/evac067] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/03/2022] [Indexed: 11/27/2022] Open
Abstract
The Balearic shearwater (Puffinus mauretanicus) is the most threatened seabird in Europe and a member of the most speciose group of pelagic seabirds, the order Procellariiformes, which exhibit extreme adaptations to a pelagic lifestyle. The fossil record suggests that human colonisation of the Balearic Islands resulted in a sharp decrease of the Balearic shearwater population size. Currently, populations of the species continue to be decimated mainly due to predation by introduced mammals and bycatch in longline fisheries, with some studies predicting its extinction by 2070. Here, using a combination of short and long reads, we generate the first high-quality reference genome for the Balearic shearwater, with a completeness amongst the highest across available avian species. We used this reference genome to study critical aspects relevant to the conservation status of the species and to gain insights into the adaptation to a pelagic lifestyle of the order Procellariiformes. We detected relatively high levels of genome-wide heterozygosity in the Balearic shearwater despite its reduced population size. However, the reconstruction of its historical demography uncovered an abrupt population decline potentially linked to a reduction of the neritic zone during the Penultimate Glacial Period (∼194-135 ka). Comparative genomics analyses uncover a set of candidate genes that may have played an important role into the adaptation to a pelagic lifestyle of Procellariiformes, including those for the enhancement of fishing capabilities, night vision, and the development of natriuresis. The reference genome obtained will be the crucial in the future development of genetic tools in conservation efforts for this Critically Endangered species.
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Affiliation(s)
- Cristian Cuevas-Caballé
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia & Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona, Spain
| | - Joan Ferrer Obiol
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia & Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona, Spain
- Department of Environmental Science and Policy, Università degli Studi di Milano (UniMi), Milan, Italy
| | - Joel Vizueta
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia & Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona, Spain
- Villum Centre for Biodiversity Genomics, Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Meritxell Genovart
- Mediterranean Institute for Advanced Studies (IMEDEA), CSIC-UIB & Centre for Advanced Studies of Blanes (CEAB), CSIC, Esporles, Spain
| | - Jacob Gonzalez-Solís
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Facultat de Biologia & Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona, Barcelona, Spain
| | - Marta Riutort
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia & Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona, Spain
| | - Julio Rozas
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia & Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona, Spain
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9
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Undin M, Lockhart PJ, Hills SFK, Armstrong DP, Castro I. Mixed Mating in a Multi-Origin Population Suggests High Potential for Genetic Rescue in North Island Brown Kiwi, Apteryx mantelli. FRONTIERS IN CONSERVATION SCIENCE 2021. [DOI: 10.3389/fcosc.2021.702128] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Reinforcement translocations are increasingly utilised in conservation with the goal of achieving genetic rescue. However, concerns regarding undesirable results, such as genetic homogenisation or replacement, are widespread. One factor influencing translocation outcomes is the rate at which the resident and the introduced individuals interbreed. Consequently, post-release mate choice is a key behaviour to consider in conservation planning. Here we studied mating, and its consequences for genomic admixture, in the North Island brown kiwi Apteryx mantelli population on Ponui Island which was founded by two translocation events over 50 years ago. The two source populations used are now recognised as belonging to two separate management units between which birds differ in size and are genetically differentiated. We examined the correlation between male and female morphometrics for 17 known pairs and quantified the relatedness of 20 pairs from this admixed population. In addition, we compared the genetic similarity and makeup of 106 Ponui Island birds, including 23 known pairs, to birds representing the source populations for the original translocations. We found no evidence for size-assortative mating. On the contrary, genomic SNP data suggested that kiwi of one feather did not flock together, meaning that mate choice resulted in pairing between individuals that were less related than expected by random chance. Furthermore, the birds in the current Ponui Island population were found to fall along a gradient of genomic composition consistent with non-clustered representation of the two parental genomes. These findings indicate potential for successful genetic rescue in future Apteryx reinforcement translocations, a potential that is currently under utilised due to restrictive translocation policies. In light of our findings, we suggest that reconsideration of these policies could render great benefits for the future diversity of this iconic genus in New Zealand.
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10
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Becciu P, Campioni L, Massa B, Dell'Omo G. Unconditional adoption rules out the need for parent–offspring recognition in a single‐brooded colonial seabird. Ethology 2021. [DOI: 10.1111/eth.13167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Paolo Becciu
- Ornis italica Rome Italy
- Animal Flight Laboratory Department of Evolutionary and Environmental Biology University of Haifa Haifa Israel
| | - Letizia Campioni
- MARE—Marine and Environmental Sciences Center ISPA—Instituto Universitário Lisboa Portugal
| | - Bruno Massa
- Department of Agriculture, Food and Forest Sciences University of Palermo Palermo Italy
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11
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Strickland LR, Fuller RC, Windsor D, Cáceres CE. A potential role for overdominance in the maintenance of colour variation in the Neotropical tortoise beetle, Chelymorpha alternans. J Evol Biol 2021; 34:779-791. [PMID: 33704867 DOI: 10.1111/jeb.13779] [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: 10/14/2020] [Revised: 03/03/2021] [Accepted: 03/06/2021] [Indexed: 11/29/2022]
Abstract
The presence of persistent polymorphisms within natural populations elicits the question of how such polymorphisms are maintained. All else equal, genetic drift and natural selection should remove genetic variants from populations. Disassortative mating and overdominance are potential mechanisms for maintaining variation within populations. Here, we consider the potential role of these mechanisms in maintaining variation in colour pattern in the tortoise beetle, Chelymorpha alternans. Five colour morphs distinguished by elytral and pronotal coloration are largely determined by a single locus of large effect with four segregating alleles. As many as four morphs co-occur in natural populations. We first assessed whether disassortative mating might maintain this polymorphism. To test for assortative and disassortative mating, we paired females with two males, one with the same colour pattern as the female and one with a different colour pattern and examined the colour patterns of the offspring. We found strong evidence for random mating as a function of colour pattern. We next assessed whether differences in offspring survival among assortative and disassortative male-female pairs maintain colour variation. Crosses involving disassortative pairings had significantly higher offspring survival during development and resulted in more adult progeny. This result is consistent with the effects of overdominance, whereby outcrossed individuals have higher fitness than their homozygous counterparts. Overall, differences in offspring survival appear to play a greater role in maintaining polymorphisms than nonrandom mating in species.
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Affiliation(s)
- Lynette R Strickland
- Department of Evolution, Ecology, and Behavior, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Rebecca C Fuller
- Department of Evolution, Ecology, and Behavior, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Donald Windsor
- Smithsonian Tropical Research Institute, Panama, Republic of Panama
| | - Carla E Cáceres
- School of Integrative Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
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12
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Whittaker DJ, Hagelin JC. Female-Based Patterns and Social Function in Avian Chemical Communication. J Chem Ecol 2020; 47:43-62. [PMID: 33103230 DOI: 10.1007/s10886-020-01230-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 09/18/2020] [Accepted: 10/20/2020] [Indexed: 11/25/2022]
Abstract
Much of the growing interest in avian chemical signals has focused on the role of kin recognition or mate attraction, often with an emphasis on males, with uropygial gland secretions perhaps providing information about an individual's identity and quality. Yet, data collected to date suggest sexual dimorphism in uropygial glands and secretions are often emphasized in female, rather than in male birds. That is, when a sexual difference occurs (often during the breeding season only), it is the female that typically exhibits one of three patterns: (1) a larger uropygial gland, (2) a greater abundance of volatile or semi-volatile preen oil compounds and/or (3) greater diversity of preen oil compounds or associated microbes. These patterns fit a majority of birds studied to date (23 of 30 chemically dimorphic species exhibit a female emphasis). Multiple species that do not fit are confounded by a lack of data for seasonal effects or proper quantitative measures of chemical compounds. We propose several social functions for these secretions in female-based patterns, similar to those reported in mammals, but which are largely unstudied in birds. These include: (1) intersexual advertisement of female receptivity or quality, including priming effects on male physiology, (2) intrasexual competition, including scent marking and reproductive suppression or (3) parental behaviors, such as parent-offspring recognition and chemical protection of eggs and nestlings. Revisiting the gaps of chemical studies to quantify the existence of female social chemosignals and any fitness benefit(s) during breeding are potentially fruitful but overlooked areas of future research.
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Affiliation(s)
- Danielle J Whittaker
- BEACON Center for the Study of Evolution in Action, Michigan State University, East Lansing, MI, 48824, USA.
| | - Julie C Hagelin
- Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK, 99775, USA
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13
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Pineaux M, Merkling T, Danchin E, Hatch S, Duneau D, Blanchard P, Leclaire S. Sex and hatching order modulate the association between MHC-II diversity and fitness in early-life stages of a wild seabird. Mol Ecol 2020; 29:3316-3329. [PMID: 32654215 DOI: 10.1111/mec.15551] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 07/04/2020] [Accepted: 07/06/2020] [Indexed: 01/04/2023]
Abstract
Genes of the major histocompatibility complex (MHC) play a pivotal role in parasite resistance, and their allelic diversity has been associated with fitness variations in several taxa. However, studies report inconsistencies in the direction of this association, with either positive, quadratic or no association being described. These discrepancies may arise because the fitness costs and benefits of MHC diversity differ among individuals depending on their exposure and immune responses to parasites. Here, we investigated in black-legged kittiwake (Rissa tridactyla) chicks whether associations between MHC class-II diversity and fitness vary with sex and hatching order. MHC-II diversity was positively associated with growth and tick clearance in female chicks, but not in male chicks. Our data also revealed a positive association between MHC-II diversity and survival in second-hatched female chicks (two eggs being the typical clutch size). These findings may result from condition-dependent parasite infections differentially impacting sexes in relation to hatching order. We thus suggest that it may be important to account for individual heterogeneities in traits that potentially exert selective pressures on MHC diversity in order to properly predict MHC-fitness associations.
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Affiliation(s)
- Maxime Pineaux
- Laboratoire Évolution & Diversité Biologique (EDB UMR 5174), CNRS, IRD, Université Fédérale de Toulouse Midi-Pyrénées, Toulouse, France
| | - Thomas Merkling
- Laboratoire Évolution & Diversité Biologique (EDB UMR 5174), CNRS, IRD, Université Fédérale de Toulouse Midi-Pyrénées, Toulouse, France
| | - Etienne Danchin
- Laboratoire Évolution & Diversité Biologique (EDB UMR 5174), CNRS, IRD, Université Fédérale de Toulouse Midi-Pyrénées, Toulouse, France
| | - Scott Hatch
- Institute for Seabird Research and Conservation, Anchorage, AK, USA
| | - David Duneau
- Laboratoire Évolution & Diversité Biologique (EDB UMR 5174), CNRS, IRD, Université Fédérale de Toulouse Midi-Pyrénées, Toulouse, France
| | - Pierrick Blanchard
- Laboratoire Évolution & Diversité Biologique (EDB UMR 5174), CNRS, IRD, Université Fédérale de Toulouse Midi-Pyrénées, Toulouse, France
| | - Sarah Leclaire
- Laboratoire Évolution & Diversité Biologique (EDB UMR 5174), CNRS, IRD, Université Fédérale de Toulouse Midi-Pyrénées, Toulouse, France
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14
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Stervander M, Dierickx EG, Thorley J, Brooke MDL, Westerdahl H. High MHC gene copy number maintains diversity despite homozygosity in a Critically Endangered single-island endemic bird, but no evidence of MHC-based mate choice. Mol Ecol 2020; 29:3578-3592. [PMID: 32416000 DOI: 10.1111/mec.15471] [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: 02/03/2020] [Revised: 04/14/2020] [Accepted: 05/04/2020] [Indexed: 12/30/2022]
Abstract
Small population sizes can, over time, put species at risk due to the loss of genetic variation and the deleterious effects of inbreeding. Losing diversity in the major histocompatibility complex (MHC) could be particularly harmful, given its key role in the immune system. Here, we assess MHC class I (MHC-I) diversity and its effects on mate choice and survival in the Critically Endangered Raso lark Alauda razae, a species restricted to the 7 km2 islet of Raso, Cape Verde, since ~1460, whose population size has dropped as low as 20 pairs. Exhaustively genotyping 122 individuals, we find no effect of MHC-I genotype/diversity on mate choice or survival. However, we demonstrate that MHC-I diversity has been maintained through extreme bottlenecks by retention of a high number of gene copies (at least 14), aided by cosegregation of multiple haplotypes comprising 2-8 linked MHC-I loci. Within-locus homozygosity is high, contributing to low population-wide diversity. Conversely, each individual had comparably many alleles, 6-16 (average 11), and the large and divergent haplotypes occur at high frequency in the population, resulting in high within-individual MHC-I diversity. This functional immune gene diversity will be of critical importance for this highly threatened species' adaptive potential.
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Affiliation(s)
- Martin Stervander
- Department of Biology, Lund University, Lund, Sweden.,Department of Biology and Environmental Science, Faculty of Health and Life Sciences, Linnaeus University, Kalmar, Sweden.,Institute of Ecology and Evolution, University of Oregon, Eugene, OR, USA
| | - Elisa G Dierickx
- Department of Zoology, University of Cambridge, Cambridge, UK.,Fauna & Flora International, Cambridge, UK
| | - Jack Thorley
- Department of Zoology, University of Cambridge, Cambridge, UK
| | - M de L Brooke
- Department of Zoology, University of Cambridge, Cambridge, UK
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15
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Wiens JJ, Tuschhoff E. Songs versus colours versus horns: what explains the diversity of sexually selected traits? Biol Rev Camb Philos Soc 2020; 95:847-864. [PMID: 32092241 DOI: 10.1111/brv.12593] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Revised: 01/25/2020] [Accepted: 02/10/2020] [Indexed: 01/14/2023]
Abstract
Papers on sexual selection often highlight the incredible diversity of sexually selected traits across animals. Yet, few studies have tried to explain why this diversity evolved. Animals use many different types of traits to attract mates and outcompete rivals, including colours, songs, and horns, but it remains unclear why, for example, some taxa have songs, others have colours, and others horns. Here, we first conduct a systematic survey of the basic diversity and distribution of different types of sexually selected signals and weapons across the animal Tree of Life. Based on this survey, we describe seven major patterns in trait diversity and distributions. We then discuss 10 unanswered questions raised by these patterns, and how they might be addressed. One major pattern is that most types of sexually selected signals and weapons are apparently absent from most animal phyla (88%), in contrast to the conventional wisdom that a diversity of sexually selected traits is present across animals. Furthermore, most trait diversity is clustered in Arthropoda and Chordata, but only within certain clades. Within these clades, many different types of traits have evolved, and many types appear to have evolved repeatedly. By contrast, other major arthropod and chordate clades appear to lack all or most trait types, and similar patterns are repeated at smaller phylogenetic scales (e.g. within insects). Although most research on sexual selection focuses on female choice, we find similar numbers of traits (among sampled species) are involved in male contests (44%) and female choice (55%). Overall, these patterns are largely unexplained and unexplored, as are many other fundamental questions about the evolution of these traits. We suggest that understanding the diversity of sexually selected traits may require a shift towards macroevolutionary studies at relatively deep timescales (e.g. tens to hundreds of millions of years ago).
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Affiliation(s)
- John J Wiens
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, 85721-0088, U.S.A
| | - E Tuschhoff
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, 85721-0088, U.S.A
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16
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Songbirds show odour-based discrimination of similarity and diversity at the major histocompatibility complex. Anim Behav 2019. [DOI: 10.1016/j.anbehav.2019.10.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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17
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Rekdal SL, Anmarkrud JA, Lifjeld JT, Johnsen A. Extra‐pair mating in a passerine bird with highly duplicated major histocompatibility complex class II: Preference for the golden mean. Mol Ecol 2019; 28:5133-5144. [DOI: 10.1111/mec.15273] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 09/30/2019] [Accepted: 10/14/2019] [Indexed: 12/26/2022]
Affiliation(s)
| | | | | | - Arild Johnsen
- Natural History Museum University of Oslo Oslo Norway
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18
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Lindsay WR, Andersson S, Bererhi B, Höglund J, Johnsen A, Kvarnemo C, Leder EH, Lifjeld JT, Ninnes CE, Olsson M, Parker GA, Pizzari T, Qvarnström A, Safran RJ, Svensson O, Edwards SV. Endless forms of sexual selection. PeerJ 2019; 7:e7988. [PMID: 31720113 PMCID: PMC6839514 DOI: 10.7717/peerj.7988] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 10/04/2019] [Indexed: 12/11/2022] Open
Abstract
In recent years, the field of sexual selection has exploded, with advances in theoretical and empirical research complementing each other in exciting ways. This perspective piece is the product of a "stock-taking" workshop on sexual selection and sexual conflict. Our aim is to identify and deliberate on outstanding questions and to stimulate discussion rather than provide a comprehensive overview of the entire field. These questions are organized into four thematic sections we deem essential to the field. First we focus on the evolution of mate choice and mating systems. Variation in mate quality can generate both competition and choice in the opposite sex, with implications for the evolution of mating systems. Limitations on mate choice may dictate the importance of direct vs. indirect benefits in mating decisions and consequently, mating systems, especially with regard to polyandry. Second, we focus on how sender and receiver mechanisms shape signal design. Mediation of honest signal content likely depends on integration of temporally variable social and physiological costs that are challenging to measure. We view the neuroethology of sensory and cognitive receiver biases as the main key to signal form and the 'aesthetic sense' proposed by Darwin. Since a receiver bias is sufficient to both initiate and drive ornament or armament exaggeration, without a genetically correlated or even coevolving receiver, this may be the appropriate 'null model' of sexual selection. Thirdly, we focus on the genetic architecture of sexually selected traits. Despite advances in modern molecular techniques, the number and identity of genes underlying performance, display and secondary sexual traits remains largely unknown. In-depth investigations into the genetic basis of sexual dimorphism in the context of long-term field studies will reveal constraints and trajectories of sexually selected trait evolution. Finally, we focus on sexual selection and conflict as drivers of speciation. Population divergence and speciation are often influenced by an interplay between sexual and natural selection. The extent to which sexual selection promotes or counteracts population divergence may vary depending on the genetic architecture of traits as well as the covariance between mating competition and local adaptation. Additionally, post-copulatory processes, such as selection against heterospecific sperm, may influence the importance of sexual selection in speciation. We propose that efforts to resolve these four themes can catalyze conceptual progress in the field of sexual selection, and we offer potential avenues of research to advance this progress.
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Affiliation(s)
- Willow R. Lindsay
- Department of Biological and Environmental Sciences, University of Gothenburg, Göteborg, Sweden
| | - Staffan Andersson
- Department of Biological and Environmental Sciences, University of Gothenburg, Göteborg, Sweden
| | - Badreddine Bererhi
- Department of Biological and Environmental Sciences, University of Gothenburg, Göteborg, Sweden
| | - Jacob Höglund
- Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden
| | - Arild Johnsen
- Natural History Museum, University of Oslo, Oslo, Norway
| | - Charlotta Kvarnemo
- Department of Biological and Environmental Sciences, University of Gothenburg, Göteborg, Sweden
| | - Erica H. Leder
- Natural History Museum, University of Oslo, Oslo, Norway
| | - Jan T. Lifjeld
- Natural History Museum, University of Oslo, Oslo, Norway
| | - Calum E. Ninnes
- Department of Biological and Environmental Sciences, University of Gothenburg, Göteborg, Sweden
- Department of Entomology and Nematology, University of Florida, Gainesville, FL, United States of America
| | - Mats Olsson
- Department of Biological and Environmental Sciences, University of Gothenburg, Göteborg, Sweden
| | - Geoff A. Parker
- Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Tommaso Pizzari
- Department of Zoology, Edward Grey Institute, University of Oxford, Oxford, United Kingdom
| | - Anna Qvarnström
- Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden
| | - Rebecca J. Safran
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, United States of America
| | - Ola Svensson
- School of Natural Sciences, Technology and Environmental Studies, Södertörn University, Huddinge, Sweden
| | - Scott V. Edwards
- Department of Organismic and Evolutionary Biology and Museum of Comparative Zoology, Harvard University, Cambridge, MA, United States of America
- Gothenburg Centre for Advanced Studies in Science and Technology, Chalmers University of Technology, Göteborg, Sweden
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19
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O'Connor EA, Westerdahl H, Burri R, Edwards SV. Avian MHC Evolution in the Era of Genomics: Phase 1.0. Cells 2019; 8:E1152. [PMID: 31561531 PMCID: PMC6829271 DOI: 10.3390/cells8101152] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 09/16/2019] [Accepted: 09/20/2019] [Indexed: 12/14/2022] Open
Abstract
Birds are a wonderfully diverse and accessible clade with an exceptional range of ecologies and behaviors, making the study of the avian major histocompatibility complex (MHC) of great interest. In the last 20 years, particularly with the advent of high-throughput sequencing, the avian MHC has been explored in great depth in several dimensions: its ability to explain ecological patterns in nature, such as mating preferences; its correlation with parasite resistance; and its structural evolution across the avian tree of life. Here, we review the latest pulse of avian MHC studies spurred by high-throughput sequencing. Despite high-throughput approaches to MHC studies, substantial areas remain in need of improvement with regard to our understanding of MHC structure, diversity, and evolution. Recent studies of the avian MHC have nonetheless revealed intriguing connections between MHC structure and life history traits, and highlight the advantages of long-term ecological studies for understanding the patterns of MHC variation in the wild. Given the exceptional diversity of birds, their accessibility, and the ease of sequencing their genomes, studies of avian MHC promise to improve our understanding of the many dimensions and consequences of MHC variation in nature. However, significant improvements in assembling complete MHC regions with long-read sequencing will be required for truly transformative studies.
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Affiliation(s)
| | | | - Reto Burri
- Department of Population Ecology, Institute of Ecology & Evolution, Friedrich Schiller University Jena, 07737 Jena, Germany.
| | - Scott V Edwards
- Department of Organismic and Evolutionary Biology and Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138, USA.
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20
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Huang K, Zhang P, Dunn DW, Wang T, Mi R, Li B. Assigning alleles to different loci in amplifications of duplicated loci. Mol Ecol Resour 2019; 19:1240-1253. [DOI: 10.1111/1755-0998.13036] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 04/30/2019] [Accepted: 05/06/2019] [Indexed: 11/28/2022]
Affiliation(s)
- Kang Huang
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences Northwest University Xi'an China
| | - Pei Zhang
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences Northwest University Xi'an China
| | - Derek W. Dunn
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences Northwest University Xi'an China
| | - Tongcheng Wang
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences Northwest University Xi'an China
| | - Rui Mi
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences Northwest University Xi'an China
| | - Baoguo Li
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences Northwest University Xi'an China
- Center for Excellence in Animal Evolution and Genetics Chinese Academy of Sciences Kunming China
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21
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Han QH, Sun RN, Yang HQ, Wang ZW, Wan QH, Fang SG. MHC class I diversity predicts non-random mating in Chinese alligators (Alligator sinensis). Heredity (Edinb) 2019; 122:809-818. [PMID: 30670843 PMCID: PMC6781117 DOI: 10.1038/s41437-018-0177-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 11/26/2018] [Accepted: 11/28/2018] [Indexed: 11/08/2022] Open
Abstract
The major histocompatibility complex (MHC) has several important roles in kin recognition, pathogen resistance and mate selection. Research in fish, birds and mammals has suggested that individuals optimise MHC diversity, and therefore offspring fitness, when choosing mates. In reptiles, however, it is unclear whether female mate choice is based on genome-wide genetic characteristics such as microsatellite DNA loci, particular functional-trait loci (e.g., MHC) or both, and MHC's effects on mate choice remain relatively understudied. Herein, we used 13 microsatellite loci and two MHC class I loci to investigate female mate choice of Chinese alligators (Alligator sinensis) in the semi-natural condition. We also determined correlations between the MHC genotype of breeding males and male reproductive success. We found that MHC-heterozygous males harbour a greater reproductive success, which probably is the reason that these males are more preferred by the females than MHC-homozygous males. Furthermore, the MHC class I amino-acid distance and functional distance of true mating pairs were higher compared with those of randomly sampled pairs. Analysis of microsatellites revealed that, despite mate choice, females did not completely avoid inbreeding. These findings are the first evidence of MHC-associated mate choice in Chinese alligators, suggesting that females may adopt different mating strategies after assessing the MHC characteristics of potential mates.
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Affiliation(s)
- Qun-Hua Han
- The Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education and State Conservation Center for Gene Resources of Endangered Wildlife, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Ru-Na Sun
- The Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education and State Conservation Center for Gene Resources of Endangered Wildlife, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Hai-Qiong Yang
- The Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education and State Conservation Center for Gene Resources of Endangered Wildlife, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Zhen-Wei Wang
- Changxing Chinese Alligator Nature Reserve, Changxing, 313100, China
| | - Qiu-Hong Wan
- The Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education and State Conservation Center for Gene Resources of Endangered Wildlife, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Sheng-Guo Fang
- The Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education and State Conservation Center for Gene Resources of Endangered Wildlife, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.
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22
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Bergès M, Choquet R, Bonadonna F. Impact of long-term behavioural studies in the wild: the blue petrel, Halobaena caerulea, case at Kerguelen. Anim Behav 2019. [DOI: 10.1016/j.anbehav.2019.03.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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23
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Whittaker DJ, Kuzel M, Burrell MJ, Soini HA, Novotny MV, DuVal EH. Chemical profiles reflect heterozygosity and seasonality in a tropical lekking passerine bird. Anim Behav 2019. [DOI: 10.1016/j.anbehav.2019.03.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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24
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Zhu Y, Wan QH, Zhang HM, Fang SG. Reproductive Strategy Inferred from Major Histocompatibility Complex-Based Inter-Individual, Sperm-Egg, and Mother-Fetus Recognitions in Giant Pandas ( Ailuropoda melanoleuca). Cells 2019; 8:cells8030257. [PMID: 30893784 PMCID: PMC6468540 DOI: 10.3390/cells8030257] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 02/18/2019] [Accepted: 03/13/2019] [Indexed: 12/05/2022] Open
Abstract
Few major histocompatibility complex (MHC)-based mate choice studies include all MHC genes at the inter-individual, sperm-egg, and mother-fetus recognition levels. We tested three hypotheses of female mate choice in a 17-year study of the giant panda (Ailuropoda melanoleuca) while using ten functional MHC loci (four MHC class I loci: Aime-C, Aime-F, Aime-I, and Aime-L; six MHC class II loci: Aime-DRA, Aime-DRB3, Aime-DQA1, Aime-DQA2, Aime-DQB1, and Aime-DQB2); five super haplotypes (SuHa, SuHaI, SuHaII, DQ, and DR); and, seven microsatellites. We found female choice for heterozygosity at Aime-C, Aime-I, and DQ and for disassortative mate choice at Aime-C, DQ, and DR at the inter-individual recognition level. High mating success occurred in MHC-dissimilar mating pairs. No significant results were found based on any microsatellite parameters, suggesting that MHCs were the mate choice target and there were no signs of inbreeding avoidance. Our results indicate Aime-DQA1- and Aime-DQA2-associated disassortative selection at the sperm-egg recognition level and a possible Aime-C- and Aime-I-associated assortative maternal immune tolerance mechanism. The MHC genes were of differential importance at the different recognition levels, so all of the functional MHC genes should be included when studying MHC-dependent reproductive mechanisms.
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Affiliation(s)
- Ying Zhu
- MOE Key Laboratory of Biosystems Homeostasis & Protection, State Conservation Centre for Gene Resources of Endangered Wildlife, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
| | - Qiu-Hong Wan
- MOE Key Laboratory of Biosystems Homeostasis & Protection, State Conservation Centre for Gene Resources of Endangered Wildlife, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
| | - He-Min Zhang
- China Conservation and Research Center for the Giant Panda, No. 98 Tongjiang Road, Dujiangyan 611800, China.
| | - Sheng-Guo Fang
- MOE Key Laboratory of Biosystems Homeostasis & Protection, State Conservation Centre for Gene Resources of Endangered Wildlife, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
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25
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Leclaire S, Strandh M, Dell'Ariccia G, Gabirot M, Westerdahl H, Bonadonna F. Plumage microbiota covaries with the major histocompatibility complex in blue petrels. Mol Ecol 2019; 28:833-846. [PMID: 30582649 DOI: 10.1111/mec.14993] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 12/05/2018] [Accepted: 12/17/2018] [Indexed: 01/04/2023]
Abstract
To increase fitness, a wide range of vertebrates preferentially mate with partners that are dissimilar at the major histocompatibility complex (MHC) or that have high MHC diversity. Although MHC often can be assessed through olfactory cues, the mechanism by which MHC genes influence odour remains largely unclear. MHC class IIB molecules, which enable recognition and elimination of extracellular bacteria, have been suggested to influence odour indirectly by shaping odour-producing microbiota, i.e. bacterial communities. However, there is little evidence of the predicted covariation between an animal's MHC genotype and its bacterial communities in scent-producing body surfaces. Here, using high-throughput sequencing, we tested the covariation between MHC class IIB genotypes and feather microbiota in the blue petrel (Halobaena caerulea), a seabird with highly developed olfaction that has been suggested to rely on oduor cues during an MHC-based mate choice. First, we show that individuals with similar MHC class IIB profiles also have similar bacterial assemblages in their feathers. Then, we show that individuals with high MHC diversity have less diverse feather microbiota and also a reduced abundance of a bacterium of the genus Arsenophonus, a genus in which some species are symbionts of avian ectoparasites. Our results, showing that feather microbiota covary with MHC, are consistent with the hypothesis that individual MHC genotype may shape the semiochemical-producing microbiota in birds.
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Affiliation(s)
- Sarah Leclaire
- Laboratoire Evolution & Diversité Biologique, UMR 5174 (CNRS, Université Paul Sabatier, ENFA), Toulouse, France.,Centre d'Ecologie Fonctionnelle et Evolutive, CNRS-CEFE, Montpellier, France
| | - Maria Strandh
- Molecular Ecology and Evolution Lab, Lund University, Lund, Sweden
| | - Gaia Dell'Ariccia
- Centre d'Ecologie Fonctionnelle et Evolutive, CNRS-CEFE, Montpellier, France
| | - Marianne Gabirot
- Centre d'Ecologie Fonctionnelle et Evolutive, CNRS-CEFE, Montpellier, France
| | | | - Francesco Bonadonna
- Centre d'Ecologie Fonctionnelle et Evolutive, CNRS-CEFE, Montpellier, France
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26
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Hacking JD, Stuart‐Fox D, Godfrey SS, Gardner MG. Specific MHC class I supertype associated with parasite infection and color morph in a wild lizard population. Ecol Evol 2018; 8:9920-9933. [PMID: 30386586 PMCID: PMC6202711 DOI: 10.1002/ece3.4479] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 07/19/2018] [Accepted: 07/23/2018] [Indexed: 12/30/2022] Open
Abstract
The major histocompatibility complex (MHC) is a large gene family that plays a central role in the immune system of all jawed vertebrates. Nonavian reptiles are underrepresented within the MHC literature and little is understood regarding the mechanisms maintaining MHC diversity in this vertebrate group. Here, we examined the relative roles of parasite-mediated selection and sexual selection in maintaining MHC class I diversity of a color polymorphic lizard. We discovered evidence for parasite-mediated selection acting via rare-allele advantage or fluctuating selection as ectoparasite load was significantly lower in the presence of a specific MHC supertype (functional clustering of alleles): supertype four. Based on comparisons between ectoparasite prevalence and load, and assessment of the impact of ectoparasite load on host fitness, we suggest that supertype four confers quantitative resistance to ticks or an intracellular tickborne parasite. We found no evidence for MHC-associated mating in terms of pair genetic distance, number of alleles, or specific supertypes. An association was uncovered between supertype four and male throat color morph. However, it is unlikely that male throat coloration acts as a signal of MHC genotype to conspecifics because we found no evidence to suggest that male throat coloration predicts male mating status. Overall, our results suggest that parasite-mediated selection plays a role in maintaining MHC diversity in this population via rare-allele advantage and/or fluctuating selection. Further work is required to determine whether sexual selection also plays a role in maintaining MHC diversity in agamid lizards.
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Affiliation(s)
- Jessica D. Hacking
- College of Science and EngineeringFlinders UniversityBedford ParkSouth AustraliaAustralia
| | - Devi Stuart‐Fox
- School of BioSciencesUniversity of MelbourneParkvilleVictoriaAustralia
| | | | - Michael G. Gardner
- College of Science and EngineeringFlinders UniversityBedford ParkSouth AustraliaAustralia
- Evolutionary Biology UnitSouth Australian MuseumAdelaideSouth AustraliaAustralia
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27
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Vanessa Huml J, Taylor MI, Edwin Harris W, Sen R, Ellis JS. Neutral variation does not predict immunogenetic variation in the European grayling (Thymallus thymallus)-implications for management. Mol Ecol 2018; 27:4157-4173. [PMID: 30194888 DOI: 10.1111/mec.14864] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 08/21/2018] [Accepted: 08/29/2018] [Indexed: 11/28/2022]
Abstract
Preservation of genetic diversity is critical to successful conservation, and there is increasing demand for the inclusion of ecologically meaningful genetic information in management decisions. Supportive breeding programmes are increasingly implemented to combat declines in many species, yet their effect on adaptive genetic variation is understudied. This is despite the fact that supportive breeding may interfere with natural evolutionary processes. Here, we assessed the performance of neutral and adaptive markers (major histocompatibility complex; MHC) to inform management of European grayling (Thymallus thymallus), which routinely involves supplementation of natural populations with hatchery-reared fish (stocking). This study is the first to characterize MH II DAA and DAB loci in grayling and to investigate immune genetic variation in relation to management practice in this species. High-throughput Illumina sequencing of "introduced," "stocked native" and "non-stocked native" populations revealed significantly higher levels of allelic richness and heterozygosity for MH markers than microsatellites exclusively in non-stocked native populations. Likewise, significantly lower differentiation at the MH II than for microsatellites was apparent when considering non-stocked native populations, but not stocked populations. We developed a simulation model to test the effects of relaxation of selection during the early life stage within captivity. Dependent on the census population size and stocking intensity, there may be long-term effects of stocking on MH II, but not neutral genetic diversity. This is consistent with our empirical results. This study highlights the necessity for considering adaptive genetic variation in conservation decisions and raises concerns about the efficiency of stocking as a management practice.
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Affiliation(s)
- J Vanessa Huml
- School of Science & Environment, Manchester Metropolitan University, Manchester, UK.,School of Biological and Marine Sciences, University of Plymouth, Plymouth, UK
| | - Martin I Taylor
- School of Biological Sciences, University of East Anglia, Norwich, UK
| | - W Edwin Harris
- School of Science & Environment, Manchester Metropolitan University, Manchester, UK
| | - Robin Sen
- School of Science & Environment, Manchester Metropolitan University, Manchester, UK
| | - Jonathan S Ellis
- School of Biological and Marine Sciences, University of Plymouth, Plymouth, UK
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28
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Hoover B, Alcaide M, Jennings S, Sin SYW, Edwards SV, Nevitt GA. Ecology can inform genetics: Disassortative mating contributes to MHC polymorphism in Leach's storm-petrels (Oceanodroma leucorhoa). Mol Ecol 2018; 27:3371-3385. [PMID: 30010226 DOI: 10.1111/mec.14801] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 05/31/2018] [Accepted: 06/20/2018] [Indexed: 01/03/2023]
Abstract
Studies of MHC-based mate choice in wild populations often test hypotheses on species exhibiting female choice and male-male competition, which reflects the general prevalence of females as the choosy sex in natural systems. Here, we examined mutual mate-choice patterns in a small burrow-nesting seabird, the Leach's storm-petrel (Oceanodroma leucorhoa), using the major histocompatibility complex (MHC). The life history and ecology of this species are extreme: both partners work together to fledge a single chick during the breeding season, a task that requires regularly travelling hundreds of kilometres to and from foraging grounds over a 6- to 8-week provisioning period. Using a 5-year data set unprecedented for this species (n = 1078 adults and 925 chicks), we found a positive relationship between variation in the likelihood of female reproductive success and heterozygosity at Ocle-DAB2, a MHC class IIB locus. Contrary to previous reports rejecting disassortative mating as a mechanism for maintaining genetic polymorphism in this species, here we show that males make significant disassortative mate-choice decisions. Variability in female reproductive success suggests that the most common homozygous females (Ocle-DAB2*01/Ocle-DAB2*01) may be physiologically disadvantaged and, therefore, less preferred as lifelong partners for choosy males. The results from this study support the role of mate choice in maintaining high levels of MHC variability in a wild seabird species and highlight the need to incorporate a broader ecological framework and sufficient sample sizes into studies of MHC-based mating patterns in wild populations in general.
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Affiliation(s)
- Brian Hoover
- Graduate Group in Ecology, University of California, Davis, California
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, California
| | - Miguel Alcaide
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Sarah Jennings
- Graduate Group in Ecology, University of California, Davis, California
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, California
| | - Simon Yung Wa Sin
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts
- School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong
| | - Scott V Edwards
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts
| | - Gabrielle A Nevitt
- Graduate Group in Ecology, University of California, Davis, California
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, California
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29
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Garamszegi LZ, Zagalska-Neubauer M, Canal D, Blázi G, Laczi M, Nagy G, Szöllősi E, Vaskuti É, Török J, Zsebők S. MHC-mediated sexual selection on birdsong: Generic polymorphism, particular alleles and acoustic signals. Mol Ecol 2018; 27:2620-2633. [PMID: 29693314 DOI: 10.1111/mec.14703] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 04/03/2018] [Accepted: 04/11/2018] [Indexed: 01/06/2023]
Abstract
Several hypotheses predict that the major histocompatibility complex (MHC) drives mating preference in females. Olfactory, colour or morphological traits are often found as reliable signals of the MHC profile, but the role of avian song mediating MHC-based female choice remains largely unexplored. We investigated the relationship between several MHC and acoustic features in the collared flycatcher (Ficedula albicollis), a European passerine with complex songs. We screened a fragment of the class IIB second exon of the MHC molecule, of which individuals harbour 4-15 alleles, while considerable sequence diversity is maintained at the population level. To make statistical inferences from a large number of comparisons, we adopted both null-hypothesis testing and effect size framework in combination with randomization procedures. After controlling for potential confounding factors, neither MHC allelic diversity nor the presence of particular alleles was associated remarkably with the investigated qualitative and quantitative song traits. Furthermore, genetic similarity among males based on MHC sequences was not reflected by the similarity in their song based on syllable content. Overall, these results suggest that the relationship between features of song and the allelic composition and diversity of MHC is not strong in the studied species. However, a biologically motivated analysis revealed that individuals that harbour an MHC allele that impairs survival perform songs with broader frequency range. This finding suggests that certain aspects of the song may bear reliable information concerning the MHC profile of the individuals, which can be used by females to optimize mate choice.
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Affiliation(s)
- László Zsolt Garamszegi
- Department of Evolutionary Ecology, Estación Biológica de Doñana-CSIC, Seville, Spain.,Department of Plant Systematics, Ecology and Theoretical Biology, MTA-ELTE, Theoretical Biology and Evolutionary Ecology Research Group, Eötvös Loránd University, Budapest, Hungary
| | | | - David Canal
- Department of Evolutionary Ecology, Estación Biológica de Doñana-CSIC, Seville, Spain.,Centro para el Estudio y Conservación de las Aves Rapaces en Argentina (CECARA-UNLPam) & Instituto de las Ciencias de la Tierra y Ambientales de La Pampa (INCITAP), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Santa Rosa, Argentina
| | - György Blázi
- Department of Systematic Zoology and Ecology, Behavioural Ecology Group, Eötvös Loránd University, Budapest, Hungary
| | - Miklós Laczi
- Department of Systematic Zoology and Ecology, Behavioural Ecology Group, Eötvös Loránd University, Budapest, Hungary
| | - Gergely Nagy
- Department of Systematic Zoology and Ecology, Behavioural Ecology Group, Eötvös Loránd University, Budapest, Hungary
| | - Eszter Szöllősi
- Department of Systematic Zoology and Ecology, Behavioural Ecology Group, Eötvös Loránd University, Budapest, Hungary
| | - Éva Vaskuti
- Department of Systematic Zoology and Ecology, Behavioural Ecology Group, Eötvös Loránd University, Budapest, Hungary
| | - János Török
- Department of Systematic Zoology and Ecology, Behavioural Ecology Group, Eötvös Loránd University, Budapest, Hungary.,Ecology Research Group, Hungarian Academy of Sciences, Budapest, Hungary
| | - Sándor Zsebők
- Department of Systematic Zoology and Ecology, Behavioural Ecology Group, Eötvös Loránd University, Budapest, Hungary
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30
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Minias P, Pikus E, Whittingham LA, Dunn PO. A global analysis of selection at the avian MHC. Evolution 2018; 72:1278-1293. [PMID: 29665025 DOI: 10.1111/evo.13490] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 03/29/2018] [Accepted: 04/09/2018] [Indexed: 12/29/2022]
Abstract
Recent advancements in sequencing technology have resulted in rapid progress in the study of the major histocompatibility complex (MHC) in non-model avian species. Here, we analyze a global dataset of avian MHC class I and class II sequences (ca. 11,000 sequences from over 250 species) to gain insight into the processes that govern macroevolution of MHC genes in birds. Analysis of substitution rates revealed striking differences in the patterns of diversifying selection between passerine and non-passerine birds. Non-passerines showed stronger selection at MHC class II, which is primarily involved in recognition of extracellular pathogens, while passerines showed stronger selection at MHC class I, which is involved in recognition of intracellular pathogens. Positions of positively selected amino-acid residues showed marked discrepancies with peptide-binding residues (PBRs) of human MHC molecules, suggesting that using a human classification of PBRs to assess selection patterns at the avian MHC may be unjustified. Finally, our analysis provided evidence that indel mutations can make a substantial contribution to adaptive variation at the avian MHC.
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Affiliation(s)
- Piotr Minias
- Department of Biodiversity Studies and Bioeducation, Faculty of Biology and Environmental Protection, University of Łódź, Łódź, 90-237, Poland
| | - Ewa Pikus
- Department of Biodiversity Studies and Bioeducation, Faculty of Biology and Environmental Protection, University of Łódź, Łódź, 90-237, Poland
| | - Linda A Whittingham
- Behavioral and Molecular Ecology Group, Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53211
| | - Peter O Dunn
- Department of Biodiversity Studies and Bioeducation, Faculty of Biology and Environmental Protection, University of Łódź, Łódź, 90-237, Poland.,Behavioral and Molecular Ecology Group, Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53211
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31
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Kvarnemo C. Why do some animals mate with one partner rather than many? A review of causes and consequences of monogamy. Biol Rev Camb Philos Soc 2018; 93:1795-1812. [PMID: 29687607 DOI: 10.1111/brv.12421] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2017] [Revised: 03/27/2018] [Accepted: 04/03/2018] [Indexed: 10/17/2022]
Abstract
Why do some animals mate with one partner rather than many? Here, I investigate factors related to (i) spatial constraints (habitat limitation, mate availability), (ii) time constraints (breeding synchrony, length of breeding season), (iii) need for parental care, and (iv) genetic compatibility, to see what support can be found in different taxa regarding the importance of these factors in explaining the occurrence of monogamy, whether shown by one sex (monogyny or monandry) or by both sexes (mutual monogamy). Focusing on reproductive rather than social monogamy whenever possible, I review the empirical literature for birds, mammals and fishes, with occasional examples from other taxa. Each of these factors can explain mating patterns in some taxa, but not in all. In general, there is mixed support for how well the factors listed above predict monogamy. The factor that shows greatest support across taxa is habitat limitation. By contrast, while a need for parental care might explain monogamy in freshwater fishes and birds, there is clear evidence that this is not the case in marine fishes and mammals. Hence, reproductive monogamy does not appear to have a single overriding explanation, but is more taxon specific. Genetic compatibility is a promising avenue for future work likely to improve our understanding of monogamy and other mating patterns. I also discuss eight important consequences of reproductive monogamy: (i) parentage, (ii) parental care, (iii) eusociality and altruism, (iv) infanticide, (v) effective population size, (vi) mate choice before mating, (vii) sexual selection, and (viii) sexual conflict. Of these, eusociality and infanticide have been subject to debate, briefly summarised herein. A common expectation is that monogamy leads to little sexual conflict and no or little sexual selection. However, as reviewed here, sexual selection can be substantial under mutual monogamy, and both sexes can be subject to such selection. Under long-term mutual monogamy, mate quality is obviously more important than mate numbers, which in turn affects the need for pre-mating mate choice. Overall, I conclude that, despite much research on genetic mating patterns, reproductive monogamy is still surprisingly poorly understood and further experimental and comparative work is needed. This review identifies several areas in need of more data and also proposes new hypotheses to test.
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Affiliation(s)
- Charlotta Kvarnemo
- Department of Biological and Environmental Sciences, University of Gothenburg, Box 463, SE-405 30 Gothenburg, Sweden
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32
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Pearson SK, Bull CM, Gardner MG. Selection outweighs drift at a fine scale: Lack of MHC differentiation within a family living lizard across geographically close but disconnected rocky outcrops. Mol Ecol 2018; 27:2204-2214. [PMID: 29603473 DOI: 10.1111/mec.14571] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Revised: 02/26/2018] [Accepted: 03/01/2018] [Indexed: 11/30/2022]
Abstract
The highly polymorphic genes of the major histocompatibility complex (MHC) are involved in disease resistance, mate choice and kin recognition. Therefore, they are widely used markers for investigating adaptive variation. Although selection is the key driver, gene flow and genetic drift also influence adaptive genetic variation, sometimes in opposing ways and with consequences for adaptive potential. To further understand the processes that generate MHC variation, it is helpful to compare variation at the MHC with that at neutral genetic loci. Differences in MHC and neutral genetic variation are useful for inferring the relative influence of selection, gene flow and drift on MHC variation. To date, such investigations have usually been undertaken at a broad spatial scale. Yet, evolutionary and ecological processes can occur at a fine spatial scale, particularly in small or fragmented populations. We investigated spatial patterns of MHC variation among three geographically close, naturally discrete, sampling sites of Egernia stokesii, an Australian lizard. The MHC of E. stokesii has recently been characterized, and there is evidence for historical selection on the MHC. We found E. stokesii MHC weakly differentiated among sites compared to microsatellites, suggesting selection, acting similarly at each site, has outweighed any effects of low gene flow or of genetic drift on E. stokesii MHC variation. Our findings demonstrate the strength of selection in shaping patterns of MHC variation or consistency at a fine spatial scale.
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Affiliation(s)
- Sarah K Pearson
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia
| | - C Michael Bull
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia
| | - Michael G Gardner
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia.,Evolutionary Biology Unit, South Australian Museum, Adelaide, SA, Australia
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33
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Hartnett CM, Parrott ML, Mulder RA, Coulson G, Magrath MJ. Opportunity for female mate choice improves reproductive outcomes in the conservation breeding program of the eastern barred bandicoot (Perameles gunnii). Appl Anim Behav Sci 2018. [DOI: 10.1016/j.applanim.2017.10.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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34
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Krause ET, Bischof HJ, Engel K, Golüke S, Maraci Ö, Mayer U, Sauer J, Caspers BA. Olfaction in the Zebra Finch ( Taeniopygia guttata ): What Is Known and Further Perspectives. ADVANCES IN THE STUDY OF BEHAVIOR 2018. [DOI: 10.1016/bs.asb.2017.11.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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35
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Slade JWG, Watson MJ, Kelly TR, Gloor GB, Bernards MA, MacDougall-Shackleton EA. Chemical composition of preen wax reflects major histocompatibility complex similarity in songbirds. Proc Biol Sci 2017; 283:rspb.2016.1966. [PMID: 27807264 DOI: 10.1098/rspb.2016.1966] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Accepted: 10/07/2016] [Indexed: 12/14/2022] Open
Abstract
In jawed vertebrates, genes of the major histocompatibility complex (MHC) play a key role in immunity by encoding cell-surface proteins that recognize and bind non-self antigens. High variability at MHC suggests that these loci may also function in social signalling such as mate choice and kin recognition. This requires that MHC genotype covaries with some perceptible phenotypic trait. In mammals and fish, MHC is signalled chemically through volatile and non-volatile peptide odour cues, facilitating MHC-dependent mate choice and other behaviours. In birds, despite evidence for MHC-dependent mating, candidate mechanisms for MHC signalling remain largely unexplored. However, feather preen wax has recently been implicated as a potential source of odour cues. We examined whether the chemical composition of preen wax correlates with MHC class IIβ genotypes of wild song sparrows (Melospiza melodia). Pairwise chemical distance reflected amino acid distance at MHC for male-female dyads, although not for same-sex dyads. Chemical diversity did not reflect MHC diversity. We used gas chromatography-mass spectrometry (GC-MS) to characterize preen wax compounds, and identified four wax esters that best reflect MHC similarity. Provided songbirds can detect variation in preen wax composition, this cue may allow individuals to assess MHC compatibility of potential mates.
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Affiliation(s)
- J W G Slade
- Biology, University of Western Ontario London, Ontario, Canada N6A 5B7
| | - M J Watson
- Biology, University of Western Ontario London, Ontario, Canada N6A 5B7
| | - T R Kelly
- Biology, University of Western Ontario London, Ontario, Canada N6A 5B7
| | - G B Gloor
- Biochemistry, University of Western Ontario London, Ontario, Canada N6A 5B7
| | - M A Bernards
- Biology, University of Western Ontario London, Ontario, Canada N6A 5B7
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36
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Nava C, Neves VC, Andris M, Dubois MP, Jarne P, Bolton M, Bried J. Reduced population size does not affect the mating strategy of a vulnerable and endemic seabird. Naturwissenschaften 2017; 104:103. [PMID: 29143134 DOI: 10.1007/s00114-017-1523-z] [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: 06/26/2017] [Revised: 10/24/2017] [Accepted: 10/27/2017] [Indexed: 11/26/2022]
Abstract
Bottleneck episodes may occur in small and isolated animal populations, which may result in decreased genetic diversity and increased inbreeding, but also in mating strategy adjustment. This was evaluated in the vulnerable and socially monogamous Monteiro's Storm-petrel Hydrobates monteiroi, a seabird endemic to the Azores archipelago which has suffered a dramatic population decline since the XVth century. To do this, we conducted a genetic study (18 microsatellite markers) in the population from Praia islet, which has been monitored over 16 years. We found no evidence that a genetic bottleneck was associated with this demographic decline. Monteiro's Storm-petrels paired randomly with respect to genetic relatedness and body measurements. Pair fecundity was unrelated to genetic relatedness between partners. We detected only two cases of extra-pair parentage associated with an extra-pair copulation (out of 71 offspring). Unsuccessful pairs were most likely to divorce the next year, but genetic relatedness between pair mates and pair breeding experience did not influence divorce. Divorce enabled individuals to improve their reproductive performances after re-mating only when the new partner was experienced. Re-pairing with an experienced partner occurred more frequently when divorcees changed nest than when they retained their nest. This study shows that even in strongly reduced populations, genetic diversity can be maintained, inbreeding does not necessarily occur, and random pairing is not risky in terms of pair lifetime reproductive success. Given, however, that we found no clear phenotypic mate choice criteria, the part played by non-morphological traits should be assessed more accurately in order to better understand seabird mating strategies.
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Affiliation(s)
- Cristina Nava
- MARE (Marine and Environmental Science Centre), IMAR (Institute of Marine Research) and LARSyS Associated Lab, Departamento de Oceanografia e Pescas, Universidade dos Açores, Açores, 9901-862, Horta, Portugal.
| | - Verónica C Neves
- MARE (Marine and Environmental Science Centre), IMAR (Institute of Marine Research) and LARSyS Associated Lab, Departamento de Oceanografia e Pescas, Universidade dos Açores, Açores, 9901-862, Horta, Portugal
- CIBIO Research Center in Biodiversity and Genetic Resources, CIBIO-Azores, Department of Science and Technology, Portugal
| | - Malvina Andris
- MARE (Marine and Environmental Science Centre), IMAR (Institute of Marine Research) and LARSyS Associated Lab, Departamento de Oceanografia e Pescas, Universidade dos Açores, Açores, 9901-862, Horta, Portugal
| | - Marie-Pierre Dubois
- Centre d'Ecologie Fonctionnelle et Evolutive, UMR 5175, Centre National de la Recherche Scientifique, Université de Montpellier, Université Paul Valéry Montpellier-Ecole Pratique des Hautes Etudes, 1919 route de Mende, 34293, Montpellier Cedex 5, France
| | - Philippe Jarne
- Centre d'Ecologie Fonctionnelle et Evolutive, UMR 5175, Centre National de la Recherche Scientifique, Université de Montpellier, Université Paul Valéry Montpellier-Ecole Pratique des Hautes Etudes, 1919 route de Mende, 34293, Montpellier Cedex 5, France
| | - Mark Bolton
- RSPB Centre for Conservation Science, UK Headquarters, The Lodge, Sandy, Bedfordshire, SG19 2DL, UK
| | - Joël Bried
- MARE (Marine and Environmental Science Centre), IMAR (Institute of Marine Research) and LARSyS Associated Lab, Departamento de Oceanografia e Pescas, Universidade dos Açores, Açores, 9901-862, Horta, Portugal
- , 8 avenue de la reine Nathalie, 64200, Biarritz, France
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37
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Pearson SK, Godfrey SS, Schwensow N, Bull CM, Gardner MG. Genes and Group Membership Predict Gidgee Skink (Egernia stokesii) Reproductive Pairs. J Hered 2017; 108:369-378. [PMID: 28407082 DOI: 10.1093/jhered/esx026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 04/10/2017] [Indexed: 01/24/2023] Open
Abstract
Due to their role in mate choice, disease resistance and kin recognition, genes of the major histocompatibility complex (MHC) are good candidates for investigating genetic-based mate choice. MHC-based mate choice is context dependent and influenced by many factors including social structure. Social structure diversity makes the Egernia group of lizards suitable for comparative studies of MHC-based mate choice. We investigated mate choice in the gidgee skink (Egernia stokesii), a lizard that exhibits high levels of social group and spatial stability. Group membership was incorporated into tests of the good genes as heterozygosity and compatible genes hypotheses for adaptive (MHC) and neutral (microsatellite) genetic diversity (n = 47 individuals genotyped). Females were more likely to pair with a male with higher MHC diversity and with whom they had a lower degree of microsatellite relatedness. Males were more likely to pair with a female with higher microsatellite heterozygosity and with whom they shared a lower proportion of MHC alleles. Lizards were more likely to mate with an individual from within, rather than outside, their social group, which confirmed earlier findings for this species and indicated mate choice had already largely occurred prior to either social group formation or acceptance of an individual into an existing group. Thus, a combination of genes and group membership, rather than group membership alone, predicted mate choice in this species. This work will contribute to an enhanced understanding of squamate group formation and a deeper understanding of the evolution of sociality within all vertebrates.
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Affiliation(s)
- Sarah K Pearson
- From the School of Biological Sciences, Flinders University of South Australia, Bedford Park 5042, Australia (Pearson, Bull, and Gardner); School of Veterinary and Life Sciences, Murdoch University, Murdoch, Australia (Godfrey); School of Biological Sciences, University of Adelaide, Adelaide, Australia (Schwensow); Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Ulm, Germany (Schwensow); and Evolutionary Biology Unit, South Australian Museum, Adelaide, Australia (Gardner)
| | - Stephanie S Godfrey
- From the School of Biological Sciences, Flinders University of South Australia, Bedford Park 5042, Australia (Pearson, Bull, and Gardner); School of Veterinary and Life Sciences, Murdoch University, Murdoch, Australia (Godfrey); School of Biological Sciences, University of Adelaide, Adelaide, Australia (Schwensow); Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Ulm, Germany (Schwensow); and Evolutionary Biology Unit, South Australian Museum, Adelaide, Australia (Gardner)
| | - Nina Schwensow
- From the School of Biological Sciences, Flinders University of South Australia, Bedford Park 5042, Australia (Pearson, Bull, and Gardner); School of Veterinary and Life Sciences, Murdoch University, Murdoch, Australia (Godfrey); School of Biological Sciences, University of Adelaide, Adelaide, Australia (Schwensow); Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Ulm, Germany (Schwensow); and Evolutionary Biology Unit, South Australian Museum, Adelaide, Australia (Gardner)
| | - C Michael Bull
- From the School of Biological Sciences, Flinders University of South Australia, Bedford Park 5042, Australia (Pearson, Bull, and Gardner); School of Veterinary and Life Sciences, Murdoch University, Murdoch, Australia (Godfrey); School of Biological Sciences, University of Adelaide, Adelaide, Australia (Schwensow); Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Ulm, Germany (Schwensow); and Evolutionary Biology Unit, South Australian Museum, Adelaide, Australia (Gardner)
| | - Michael G Gardner
- From the School of Biological Sciences, Flinders University of South Australia, Bedford Park 5042, Australia (Pearson, Bull, and Gardner); School of Veterinary and Life Sciences, Murdoch University, Murdoch, Australia (Godfrey); School of Biological Sciences, University of Adelaide, Adelaide, Australia (Schwensow); Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Ulm, Germany (Schwensow); and Evolutionary Biology Unit, South Australian Museum, Adelaide, Australia (Gardner)
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38
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Lukasch B, Westerdahl H, Strandh M, Knauer F, Winkler H, Moodley Y, Hoi H. Major histocompatibility complex genes partly explain early survival in house sparrows. Sci Rep 2017; 7:6571. [PMID: 28747735 PMCID: PMC5529587 DOI: 10.1038/s41598-017-06631-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 06/15/2017] [Indexed: 01/11/2023] Open
Abstract
Environmental factors and genetic incompatibilities between parents have been suggested as important determinants for embryonic mortality and survival. The genetic set-up of the immune system, specifically the highly polymorphic major histocompatibility complex (MHC) may also influence individual resistance to infections. MHC proteins are important for an appropriate adaptive immune response and enable T-cells to separate 'self' from 'non-self'. Here we investigate the importance of MHC functional diversity for early development in birds, more specifically, if offspring survival and body mass or size depends on number of different functional MHC alleles, specific functional MHC alleles or similarity of MHC alleles in the parents. Unhatched eggs are common in clutches of many bird species. In house sparrows (Passer domesticus), embryo and nestling mortality can exceed 50%. To control for environmental factors, our study was carried out on an aviary population. We found that one specific functional MHC allele was associated with reduced nestling survival, which was additionally supported by lower body mass and a smaller tarsus when nestlings have been 6 days old. Another allele was positively associated with tarsus length at a later nestling stage (nestlings 12 days old). These results indicate that MHC alleles might influence pathogen resistance or susceptibility.
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Affiliation(s)
- B Lukasch
- Konrad Lorenz Institute of Ethology, Department of Integrative Biology and Evolution, University of Veterinary Medicine, Vienna; Savoyenstraße 1a, A-1160, Vienna, Austria
| | - H Westerdahl
- Molecular Ecology & Evolution Lab, Department of Biology, Lund University, Ecology Building, Sölvegatan 37, SE-223 62, Lund, Sweden
| | - M Strandh
- Molecular Ecology & Evolution Lab, Department of Biology, Lund University, Ecology Building, Sölvegatan 37, SE-223 62, Lund, Sweden
| | - F Knauer
- Research Institute of Wildlife Ecology, Department of Integrative Biology and Evolution, University of Veterinary Medicine, Vienna; Savoyenstraße 1a, A-1160, Vienna, Austria
| | - H Winkler
- Konrad Lorenz Institute of Ethology, Department of Integrative Biology and Evolution, University of Veterinary Medicine, Vienna; Savoyenstraße 1a, A-1160, Vienna, Austria
| | - Y Moodley
- Konrad Lorenz Institute of Ethology, Department of Integrative Biology and Evolution, University of Veterinary Medicine, Vienna; Savoyenstraße 1a, A-1160, Vienna, Austria
- Department of Zoology, University of Venda, Private Bag X5050, Thohoyandou, 0950, Republic of South Africa
| | - H Hoi
- Konrad Lorenz Institute of Ethology, Department of Integrative Biology and Evolution, University of Veterinary Medicine, Vienna; Savoyenstraße 1a, A-1160, Vienna, Austria.
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Biedrzycka A, O'Connor E, Sebastian A, Migalska M, Radwan J, Zając T, Bielański W, Solarz W, Ćmiel A, Westerdahl H. Extreme MHC class I diversity in the sedge warbler (Acrocephalus schoenobaenus); selection patterns and allelic divergence suggest that different genes have different functions. BMC Evol Biol 2017; 17:159. [PMID: 28679358 PMCID: PMC5497381 DOI: 10.1186/s12862-017-0997-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 06/14/2017] [Indexed: 11/23/2022] Open
Abstract
Background Recent work suggests that gene duplications may play an important role in the evolution of immunity genes. Passerine birds, and in particular Sylvioidea warblers, have highly duplicated major histocompatibility complex (MHC) genes, which are key in immunity, compared to other vertebrates. However, reasons for this high MHC gene copy number are yet unclear. High-throughput sequencing (HTS) allows MHC genotyping even in individuals with extremely duplicated genes. This HTS data can reveal evidence of selection, which may help to unravel the putative functions of different gene copies, i.e. neofunctionalization. We performed exhaustive genotyping of MHC class I in a Sylvioidea warbler, the sedge warbler, Acrocephalus schoenobaenus, using the Illumina MiSeq technique on individuals from a wild study population. Results The MHC diversity in 863 genotyped individuals by far exceeds that of any other bird species described to date. A single individual could carry up to 65 different alleles, a large proportion of which are expressed (transcribed). The MHC alleles were of three different lengths differing in evidence of selection, diversity and divergence within our study population. Alleles without any deletions and alleles containing a 6 bp deletion showed characteristics of classical MHC genes, with evidence of multiple sites subject to positive selection and high sequence divergence. In contrast, alleles containing a 3 bp deletion had no sites subject to positive selection and had low divergence. Conclusions Our results suggest that sedge warbler MHC alleles that either have no deletion, or contain a 6 bp deletion, encode classical antigen presenting MHC molecules. In contrast, MHC alleles containing a 3 bp deletion may encode molecules with a different function. This study demonstrates that highly duplicated MHC genes can be characterised with HTS and that selection patterns can be useful for revealing neofunctionalization. Importantly, our results highlight the need to consider the putative function of different MHC genes in future studies of MHC in relation to disease resistance and fitness. Electronic supplementary material The online version of this article (doi:10.1186/s12862-017-0997-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Aleksandra Biedrzycka
- Institute of Nature Conservation, Polish Academy of Sciences, Al. Mickiewicza 33, 31-120, Kraków, Poland.
| | - Emily O'Connor
- Molecular Ecology and Evolution Lab, Department of Biology, Lund University, Ecology Building, Sölvegatan 37, 223 62, Lund, Sweden
| | - Alvaro Sebastian
- Evolutionary Biology Group, Faculty of Biology, Adam Mickiewicz University in Poznań, ul. Umultowska 89, 61-614, Poznań, Poland
| | - Magdalena Migalska
- Evolutionary Biology Group, Faculty of Biology, Adam Mickiewicz University in Poznań, ul. Umultowska 89, 61-614, Poznań, Poland
| | - Jacek Radwan
- Evolutionary Biology Group, Faculty of Biology, Adam Mickiewicz University in Poznań, ul. Umultowska 89, 61-614, Poznań, Poland
| | - Tadeusz Zając
- Institute of Nature Conservation, Polish Academy of Sciences, Al. Mickiewicza 33, 31-120, Kraków, Poland
| | - Wojciech Bielański
- Institute of Nature Conservation, Polish Academy of Sciences, Al. Mickiewicza 33, 31-120, Kraków, Poland
| | - Wojciech Solarz
- Institute of Nature Conservation, Polish Academy of Sciences, Al. Mickiewicza 33, 31-120, Kraków, Poland
| | - Adam Ćmiel
- Institute of Nature Conservation, Polish Academy of Sciences, Al. Mickiewicza 33, 31-120, Kraków, Poland
| | - Helena Westerdahl
- Molecular Ecology and Evolution Lab, Department of Biology, Lund University, Ecology Building, Sölvegatan 37, 223 62, Lund, Sweden
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40
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Santos PSC, Michler FU, Sommer S. Can MHC-assortative partner choice promote offspring diversity? A new combination of MHC-dependent behaviours among sexes in a highly successful invasive mammal. Mol Ecol 2017; 26:2392-2404. [PMID: 28141891 DOI: 10.1111/mec.14035] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 01/18/2017] [Accepted: 01/20/2017] [Indexed: 01/19/2023]
Abstract
Sexual selection involving genetically disassortative mate choice is one of several evolutionary processes that can maintain or enhance population genetic variability. Examples of reproductive systems in which choosers (generally females) select mates depending on their major histocompatibility complex (MHC) genes have been reported for several vertebrate species. Notably, the role of MHC-dependent choice not in mating contexts, but in other kinds of social interactions such as in the establishment of complex social systems, has not yet drawn significant scientific interest and is virtually absent from the literature. We have investigated male and female MHC-dependent choice in an invasive population of North American raccoons (Procyon lotor) in Germany. Both male and female raccoons rely on olfaction for individual recognition. Males have an unusually complex social system in which older individuals choose unrelated younger ones to form stable male coalitions that defend territories and a monopoly over females. We have confirmed that females perform MHC-disassortative mate choice and that this behaviour fosters genetic diversity of offspring. We have also observed that males build coalitions by choosing male partners depending on their MHC, but in an assortative manner. This is the first observation of antagonistic MHC-dependent behaviours among sexes. We show that this is the only combination of MHC-dependent partner choice that leads to outbreeding. In the case of introduced raccoons, such behaviours can act together to promote the invasive potential of the species by increasing its adaptive genetic divergence.
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Affiliation(s)
- Pablo S C Santos
- Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Albert-Einstein-Allee 11, 89069, Ulm, Germany
| | - Frank-Uwe Michler
- Institute of Forest Botany and Forest Zoology, Technical University of Dresden, Pienner Straße 7, 01737, Tharandt, Germany
| | - Simone Sommer
- Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Albert-Einstein-Allee 11, 89069, Ulm, Germany
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41
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Gillingham MAF, Béchet A, Courtiol A, Rendón-Martos M, Amat JA, Samraoui B, Onmuş O, Sommer S, Cézilly F. Very high MHC Class IIB diversity without spatial differentiation in the mediterranean population of greater Flamingos. BMC Evol Biol 2017; 17:56. [PMID: 28219340 PMCID: PMC5319168 DOI: 10.1186/s12862-017-0905-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 02/06/2017] [Indexed: 02/07/2023] Open
Abstract
Background Selective pressure from pathogens is thought to shape the allelic diversity of major histocompatibility complex (MHC) genes in vertebrates. In particular, both local adaptation to pathogens and gene flow are thought to explain a large part of the intraspecific variation observed in MHC allelic diversity. To date, however, evidence that adaptation to locally prevalent pathogens maintains MHC variation is limited to species with limited dispersal and, hence, reduced gene flow. On the one hand high gene flow can disrupt local adaptation in species with high dispersal rates, on the other hand such species are much more likely to experience spatial variation in pathogen pressure, suggesting that there may be intense pathogen mediated selection pressure operating across breeding sites in panmictic species. Such pathogen mediated selection pressure operating across breeding sites should therefore be sufficient to maintain high MHC diversity in high dispersing species in the absence of local adaptation mechanisms. We used the Greater Flamingo, Phoenicopterus roseus, a long-lived colonial bird showing a homogeneous genetic structure of neutral markers at the scale of the Mediterranean region, to test the prediction that higher MHC allelic diversity with no population structure should occur in large panmictic populations of long-distance dispersing birds than in other resident species. Results We assessed the level of allelic diversity at the MHC Class IIB exon 2 from 116 individuals born in four different breeding colonies of Greater Flamingo in the Mediterranean region. We found one of the highest allelic diversity (109 alleles, 2 loci) of any non-passerine avian species investigated so far relative to the number of individuals and loci genotyped. There was no evidence of population structure between the four major Mediterranean breeding colonies. Conclusion Our results suggest that local adaptation at MHC Class IIB in Greater Flamingos is constrained by high gene flow and high MHC diversity appears to be maintained by population wide pathogen-mediated selection rather than local pathogen-mediated selection. Further understanding of how pathogens vary across space and time will be crucial to further elucidate the mechanisms maintaining MHC diversity in species with large panmictic populations and high dispersal rates. Electronic supplementary material The online version of this article (doi:10.1186/s12862-017-0905-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Mark A F Gillingham
- University of Ulm, Institute of Evolutionary Ecology and Conservation Genomics, Albert-Einstein Allee 11, D-89069, Ulm, Germany. .,Université de Bourgogne, Equipe Ecologie Evolutive, UMR CNRS 6282 Biogéosciences, 6 bd. Gabriel, 21000, Dijon, France. .,Centre de Recherche de la Tour du Valat, Le Sambuc, 13200, Arles, France. .,Leibniz Institute for Zoo and Wildlife Research, Evolutionary Genetics, Alfred-Kowalke-Str. 17, D-10315, Berlin, Germany.
| | - Arnaud Béchet
- Centre de Recherche de la Tour du Valat, Le Sambuc, 13200, Arles, France
| | - Alexandre Courtiol
- Leibniz Institute for Zoo and Wildlife Research, Evolutionary Genetics, Alfred-Kowalke-Str. 17, D-10315, Berlin, Germany.,Berlin Center for Genomics in Biodiversity Research (BeGenDiv), D-14195, Berlin, Germany
| | - Manuel Rendón-Martos
- R.N. Laguna de Fuente de Piedra, Consejería de Medio Ambiente y Ordenación del Territorio, Junta de Andalucía, Apartado 1, E-29520 Fuente de Piedra, (Málaga), Spain
| | - Juan A Amat
- Department of Wetland Ecology, Estación Biológica de Doñana, (EBD-CSIC), calle Américo Vespucio s/n, E-41092, Sevilla, Spain
| | - Boudjéma Samraoui
- Center of Excellence for Research in Biodiversity, King Saud University, Riyadh, Saudi Arabia.,Laboratoire de recherche et de conservation des zones humides, University of Guelma, Guelma, Algeria
| | - Ortaç Onmuş
- Natural History Museum, Faculty of Sciences, Department of Biology, Ege University, Bornova, İzmir, Turkey
| | - Simone Sommer
- University of Ulm, Institute of Evolutionary Ecology and Conservation Genomics, Albert-Einstein Allee 11, D-89069, Ulm, Germany
| | - Frank Cézilly
- Université de Bourgogne, Equipe Ecologie Evolutive, UMR CNRS 6282 Biogéosciences, 6 bd. Gabriel, 21000, Dijon, France.,Institut Universitaire de France, Paris, France
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42
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Structure and polymorphisms of the major histocompatibility complex in the Oriental stork, Ciconia boyciana. Sci Rep 2017; 7:42864. [PMID: 28211522 PMCID: PMC5314415 DOI: 10.1038/srep42864] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 01/18/2017] [Indexed: 12/27/2022] Open
Abstract
The major histocompatibility complex (MHC) is highly polymorphic and plays a central role in the vertebrate immune system. Despite its functional consistency, the MHC genomic structure differs substantially among organisms. In birds, the MHCs of Galliformes and the Japanese crested ibis (Pelecaniformes) are well-characterized, but information about other avian MHCs remains scarce. The Oriental stork (Ciconia boyciana, order Ciconiiformes) is a large endangered migrant. The current Japanese population of this bird originates from a few founders; thus, understanding the genetic diversity among them is critical for effective population management. We report the structure and polymorphisms in C. boyciana MHC. One contig (approximately 128 kb) was assembled by screening of lambda phage genomic library and its complete sequence was determined, revealing a gene order of COL11A2, two copies of MHC-IIA/IIB pairs, BRD2, DMA/B1/B2, MHC-I, TAP1/2, and two copies each of pseudo MHC-I and TNXB. This structure was highly similar to that of the Japanese crested ibis, but largely different from that of Galliformes, at both the terminal regions. Genotyping of the MHC-II region detected 10 haplotypes among the six founders. These results provide valuable insights for future studies on the evolution of the avian MHCs and for conservation of C. boyciana.
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43
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Rymešová D, Králová T, Promerová M, Bryja J, Tomášek O, Svobodová J, Šmilauer P, Šálek M, Albrecht T. Mate choice for major histocompatibility complex complementarity in a strictly monogamous bird, the grey partridge ( Perdix perdix). Front Zool 2017; 14:9. [PMID: 28239400 PMCID: PMC5312559 DOI: 10.1186/s12983-017-0194-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 02/01/2017] [Indexed: 11/17/2022] Open
Abstract
Background Sexual selection has been hypothesised as favouring mate choice resulting in production of viable offspring with genotypes providing high pathogen resistance. Specific pathogen recognition is mediated by genes of the major histocompatibility complex (MHC) encoding proteins fundamental for adaptive immune response in jawed vertebrates. MHC genes may also play a role in odour-based individual recognition and mate choice, aimed at avoiding inbreeding. MHC genes are known to be involved in mate choice in a number of species, with ‘good genes’ (absolute criteria) and ‘complementary genes’ (self-referential criteria) being used to explain MHC-based mating. Here, we focus on the effect of morphological traits and variation and genetic similarity between individuals in MHC class IIB (MHCIIB) exon 2 on mating in a free-living population of a monogamous bird, the grey partridge. Results We found no evidence for absolute mate choice criteria as regards grey partridge MHCIIB genotypes, i.e., number and occurrence of amino acid variants, though red chroma of the spot behind eyes was positively associated with male pairing success. On the other hand, mate choice at MHCIIB was based on relative criteria as females preferentially paired with more dissimilar males having a lower number of shared amino acid variants. This observation supports the ‘inbreeding avoidance’ and ‘complementary genes’ hypotheses. Conclusions Our study provides one of the first pieces of evidence for MHC-based mate choice for genetic complementarity in a strictly monogamous bird. The statistical approach employed can be recommended for testing mating preferences in cases where availability of potential mates (recorded with an appropriate method such as radio-tracking) shows considerable temporal variation. Additional genetic analyses using neutral markers may detect whether MHC-based mate choice for complementarity emerges as a by-product of general inbreeding avoidance in grey partridges. Electronic supplementary material The online version of this article (doi:10.1186/s12983-017-0194-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Dana Rymešová
- Department of Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences, Kamýcká 1176, 165 21 Prague 6, Czech Republic.,Department of Botany and Zoology, Faculty of Science, Masaryk University, Czech Republic, Kotlářská 2, 611 37 Brno, Czech Republic
| | - Tereza Králová
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Czech Republic, Kotlářská 2, 611 37 Brno, Czech Republic.,Institute of Vertebrate Biology, The Czech Academy of Sciences, Květná 8, 603 65 Brno, Czech Republic
| | - Marta Promerová
- Institute of Vertebrate Biology, The Czech Academy of Sciences, Květná 8, 603 65 Brno, Czech Republic.,Department of Evolutionary Biology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, SE-75236 Uppsala, Sweden
| | - Josef Bryja
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Czech Republic, Kotlářská 2, 611 37 Brno, Czech Republic.,Institute of Vertebrate Biology, The Czech Academy of Sciences, Květná 8, 603 65 Brno, Czech Republic
| | - Oldřich Tomášek
- Institute of Vertebrate Biology, The Czech Academy of Sciences, Květná 8, 603 65 Brno, Czech Republic.,Department of Zoology, Faculty of Science, Charles University in Prague, Viničná 7, 128 44 Prague 2, Czech Republic
| | - Jana Svobodová
- Department of Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences, Kamýcká 1176, 165 21 Prague 6, Czech Republic
| | - Petr Šmilauer
- Department of Ecosystem Biology, Faculty of Science, University of South Bohemia, Branišovská 1760, 370 05 České Budějovice, Czech Republic
| | - Miroslav Šálek
- Department of Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences, Kamýcká 1176, 165 21 Prague 6, Czech Republic
| | - Tomáš Albrecht
- Institute of Vertebrate Biology, The Czech Academy of Sciences, Květná 8, 603 65 Brno, Czech Republic.,Department of Zoology, Faculty of Science, Charles University in Prague, Viničná 7, 128 44 Prague 2, Czech Republic
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44
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Leclaire S, Strandh M, Mardon J, Westerdahl H, Bonadonna F. Odour-based discrimination of similarity at the major histocompatibility complex in birds. Proc Biol Sci 2017; 284:20162466. [PMID: 28077776 PMCID: PMC5247505 DOI: 10.1098/rspb.2016.2466] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 12/06/2016] [Indexed: 11/12/2022] Open
Abstract
Many animals are known to preferentially mate with partners that are dissimilar at the major histocompatibility complex (MHC) in order to maximize the antigen binding repertoire (or disease resistance) in their offspring. Although several mammals, fish or lizards use odour cues to assess MHC similarity with potential partners, the ability of birds to assess MHC similarity using olfactory cues has not yet been explored. Here we used a behavioural binary choice test and high-throughput-sequencing of MHC class IIB to determine whether blue petrels can discriminate MHC similarity based on odour cues alone. Blue petrels are seabirds with particularly good sense of smell, they have a reciprocal mate choice and are known to preferentially mate with MHC-dissimilar partners. Incubating males preferentially approached the odour of the more MHC-dissimilar female, whereas incubating females showed opposite preferences. Given their mating pattern, females were, however, expected to show preference for the odour of the more MHC-dissimilar male. Further studies are needed to determine whether, as in women and female mice, the preference varies with the reproductive cycle in blue petrel females. Our results provide the first evidence that birds can use odour cues only to assess MHC dissimilarity.
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Affiliation(s)
- Sarah Leclaire
- Centre d'Ecologie Fonctionnelle et Evolutive, CNRS-CEFE, 1919 route de Mende, 34293 Montpellier, France
| | - Maria Strandh
- Molecular Ecology and Evolution Lab, Lund University, Ecology building, 22362 Lund, Sweden
| | - Jérôme Mardon
- Centre d'Ecologie Fonctionnelle et Evolutive, CNRS-CEFE, 1919 route de Mende, 34293 Montpellier, France
| | - Helena Westerdahl
- Molecular Ecology and Evolution Lab, Lund University, Ecology building, 22362 Lund, Sweden
| | - Francesco Bonadonna
- Centre d'Ecologie Fonctionnelle et Evolutive, CNRS-CEFE, 1919 route de Mende, 34293 Montpellier, France
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45
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Santos PSC, Courtiol A, Heidel AJ, Höner OP, Heckmann I, Nagy M, Mayer F, Platzer M, Voigt CC, Sommer S. MHC-dependent mate choice is linked to a trace-amine-associated receptor gene in a mammal. Sci Rep 2016; 6:38490. [PMID: 27941813 PMCID: PMC5150237 DOI: 10.1038/srep38490] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 11/11/2016] [Indexed: 01/28/2023] Open
Abstract
Major histocompatibility complex (MHC) genes play a pivotal role in vertebrate self/nonself recognition, parasite resistance and life history decisions. In evolutionary terms, the MHC’s exceptional diversity is likely maintained by sexual and pathogen-driven selection. Even though MHC-dependent mating preferences have been confirmed for many species, the sensory and genetic mechanisms underlying mate recognition remain cryptic. Since olfaction is crucial for social communication in vertebrates, variation in chemosensory receptor genes could explain MHC-dependent mating patterns. Here, we investigated whether female mate choice is based on MHC alleles and linked to variation in chemosensory trace amine-associated receptors (TAARs) in the greater sac-winged bat (Saccopteryx bilineata). We sequenced several MHC and TAAR genes and related their variation to mating and paternity data. We found strong evidence for MHC class I-dependent female choice for genetically diverse and dissimilar males. We also detected a significant interaction between mate choice and the female TAAR3 genotype, with TAAR3-heterozygous females being more likely to choose MHC-diverse males. These results suggest that TAARs and olfactory cues may be key mediators in mammalian MHC-dependent mate choice. Our study may help identify the ligands involved in the chemical communication between potential mates.
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Affiliation(s)
- Pablo S C Santos
- Leibniz Institute for Zoo and Wildlife Research (IZW) Berlin, Germany.,Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Ulm, Germany
| | - Alexandre Courtiol
- Leibniz Institute for Zoo and Wildlife Research (IZW) Berlin, Germany.,Berlin Center for Genomics in Biodiversity Research (BeGenDiv), 14195 Berlin, Germany
| | - Andrew J Heidel
- Leibniz Institute on Age - Fritz Lipmann Institute, Jena, Germany
| | - Oliver P Höner
- Leibniz Institute for Zoo and Wildlife Research (IZW) Berlin, Germany
| | - Ilja Heckmann
- Leibniz Institute for Zoo and Wildlife Research (IZW) Berlin, Germany
| | - Martina Nagy
- Museum für Naturkunde, Leibniz Institute for Research on Evolution and Biodiversity, Berlin, Germany
| | - Frieder Mayer
- Museum für Naturkunde, Leibniz Institute for Research on Evolution and Biodiversity, Berlin, Germany
| | - Matthias Platzer
- Leibniz Institute on Age - Fritz Lipmann Institute, Jena, Germany
| | - Christian C Voigt
- Leibniz Institute for Zoo and Wildlife Research (IZW) Berlin, Germany
| | - Simone Sommer
- Leibniz Institute for Zoo and Wildlife Research (IZW) Berlin, Germany.,Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Ulm, Germany
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46
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Biedrzycka A, Sebastian A, Migalska M, Westerdahl H, Radwan J. Testing genotyping strategies for ultra-deep sequencing of a co-amplifying gene family: MHC class I in a passerine bird. Mol Ecol Resour 2016; 17:642-655. [DOI: 10.1111/1755-0998.12612] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 02/10/2016] [Accepted: 08/23/2016] [Indexed: 12/15/2022]
Affiliation(s)
- Aleksandra Biedrzycka
- Institute of Nature Conservation; Polish Academy of Sciences; Al. Mickiewicza 33 31-120 Kraków Poland
| | - Alvaro Sebastian
- Evolutionary Biology Group; Faculty of Biology; Adam Mickiewicz University; ul. Umultowska 89 61-614 Poznań Poland
| | - Magdalena Migalska
- Evolutionary Biology Group; Faculty of Biology; Adam Mickiewicz University; ul. Umultowska 89 61-614 Poznań Poland
| | - Helena Westerdahl
- Department of Biology; Lund University; Ecology Building, Sölvegatan 37 223 62 Lund Sweden
| | - Jacek Radwan
- Evolutionary Biology Group; Faculty of Biology; Adam Mickiewicz University; ul. Umultowska 89 61-614 Poznań Poland
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47
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Friesen MR, Beggs JR, Gaskett AC. Sensory-based conservation of seabirds: a review of management strategies and animal behaviours that facilitate success. Biol Rev Camb Philos Soc 2016; 92:1769-1784. [PMID: 27807946 DOI: 10.1111/brv.12308] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Revised: 09/21/2016] [Accepted: 09/26/2016] [Indexed: 11/29/2022]
Abstract
Sensory-based conservation harnesses species' natural communication and signalling behaviours to mitigate threats to wild populations. To evaluate this emerging field, we assess how sensory-based manipulations, sensory mode, and target taxa affect success. To facilitate broader, cross-species application of successful techniques, we test which behavioural and life-history traits correlate with positive conservation outcomes. We focus on seabirds, one of the world's most rapidly declining groups, whose philopatry, activity patterns, foraging, mate choice, and parental care behaviours all involve reliance on, and therefore strong selection for, sophisticated sensory physiology and accurate assessment of intra- and inter-species signals and cues in several sensory modes. We review the use of auditory, olfactory, and visual methods, especially for attracting seabirds to newly restored habitat or deterring birds from fishing boats and equipment. We found that more sensory-based conservation has been attempted with Procellariiformes (tube-nosed seabirds) and Charadriiformes (e.g. terns and gulls) than other orders, and that successful outcomes are more likely for Procellariiformes. Evolutionary and behavioural traits are likely to facilitate sensory-based techniques, such as social attraction to suitable habitat, across seabird species. More broadly, successful application of sensory-based conservation to other at-risk animal groups is likely to be associated with these behavioural and life-history traits: coloniality, philopatry, nocturnal, migratory, long-distance foraging, parental care, and pair bonds/monogamy.
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Affiliation(s)
- Megan R Friesen
- Centre for Biodiversity and Biosecurity, School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Jacqueline R Beggs
- Centre for Biodiversity and Biosecurity, School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Anne C Gaskett
- Centre for Biodiversity and Biosecurity, School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
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48
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Burger D, Meuwly C, Marti E, Sieme H, Oberthür M, Janda J, Meinecke-Tillmann S, Wedekind C. MHC-correlated preferences in diestrous female horses (Equus caballus). Theriogenology 2016; 89:318-323.e1. [PMID: 27842717 DOI: 10.1016/j.theriogenology.2016.09.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2016] [Revised: 09/07/2016] [Accepted: 09/07/2016] [Indexed: 12/29/2022]
Abstract
Genes of the major histocompatibility complex (MHC) have been shown to influence communication in many vertebrates, possibly with context-specific MHC-correlated reactions. Here we test for MHC-linked female preferences in the polygynous horse (Equus caballus) by repeatedly exposing 19 mares to a group of seven sexually experienced stallions. Each mare was tested four times during two consecutive reproductive cycles, twice during estrus and twice during diestrus. Male plasma testosterone concentrations were determined from weekly blood samples, and equine leukocyte antigen (ELA) class I and II alleles were determined serologically at the end of the experiments. Perception of male attractiveness was strongly dependent on estrous cycle: mean preference scores did not correlate for mares in diestrus and estrus and varied more during estrus than during diestrus. We found elevated female interests for MHC-dissimilar stallions, but only during diestrus, not during estrus. Female preferences were not significantly predicted by mean male testosterone plasma concentrations. However, testosterone concentrations changed during the 11 weeks of the experiment. By the end of the experiment, average testosterone concentration was significantly correlated to the average number of MHC alleles the stallions shared with the mares. We conclude that the MHC affects female preferences for stallions, but non-MHC linked male characteristics can overshadow effects of the MHC during estrus.
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Affiliation(s)
- D Burger
- Swiss Institute of Equine Medicine, Agroscope and University of Bern, Avenches, Switzerland.
| | - C Meuwly
- Swiss Institute of Equine Medicine, Agroscope and University of Bern, Avenches, Switzerland
| | - E Marti
- Department of Clinical Research, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - H Sieme
- Institute for Reproductive Biology, University of Veterinary Medicine Hanover, Hanover, Germany
| | - M Oberthür
- Unit for Reproductive Medicine-Clinic for Horses, University of Veterinary Medicine Hanover, Hanover, Germany
| | - J Janda
- Department of Clinical Research, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - S Meinecke-Tillmann
- Unit for Reproductive Medicine-Clinic for Horses, University of Veterinary Medicine Hanover, Hanover, Germany
| | - C Wedekind
- Department of Ecology and Evolution, Biophore, University of Lausanne, Lausanne, Switzerland
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Hoover B, Nevitt G. Modeling the Importance of Sample Size in Relation to Error in MHC-Based Mate-Choice Studies on Natural Populations. Integr Comp Biol 2016; 56:925-933. [DOI: 10.1093/icb/icw105] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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50
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Egernia stokesii (gidgee skink) MHC I positively selected sites lack concordance with HLA peptide binding regions. Immunogenetics 2016; 69:49-61. [PMID: 27517292 DOI: 10.1007/s00251-016-0947-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2016] [Accepted: 07/25/2016] [Indexed: 10/21/2022]
Abstract
Genes of the major histocompatibility complex (MHC) play an important role in vertebrate disease resistance, kin recognition and mate choice. Mammalian MHC is the most widely characterised of all vertebrates, and attention is often given to the peptide binding regions of the MHC because they are presumed to be under stronger selection than non-peptide binding regions. For vertebrates where the MHC is less well understood, researchers commonly use the amino acid positions of the peptide binding regions of the human leukocyte antigen (HLA) to infer the peptide binding regions within the MHC sequences of their taxon of interest. However, positively selected sites within MHC have been reported to lack correspondence with the HLA in fish, frogs, birds and reptiles including squamates. Despite squamate diversity, the MHC has been characterised in few snakes and lizards. The Egernia group of scincid lizards is appropriate for investigating mechanisms generating MHC variation, as their inclusion will add a new lineage (i.e. Scincidae) to studies of selection on the MHC. We aimed to identify positively selected sites within the MHC of Egernia stokesii and then determine if these sites corresponded with the peptide binding regions of the HLA. Six positively selected sites were identified within E. stokesii MHC I, only two were homologous with the HLA. E. stokesii positively selected sites corresponded more closely to non-lizard than other lizard taxa. The characterisation of the MHC of more intermediate taxa within the squamate order is necessary to understand the evolution of the MHC across all vertebrates.
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