1
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Langmore NE, Grealy A, Noh HJ, Medina I, Skeels A, Grant J, Murray KD, Kilner RM, Holleley CE. Coevolution with hosts underpins speciation in brood-parasitic cuckoos. Science 2024; 384:1030-1036. [PMID: 38815013 DOI: 10.1126/science.adj3210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 04/23/2024] [Indexed: 06/01/2024]
Abstract
Coevolution between interacting species is thought to increase biodiversity, but evidence linking microevolutionary processes to macroevolutionary patterns is scarce. We leveraged two decades of behavioral research coupled with historical DNA analysis to reveal that coevolution with hosts underpins speciation in brood-parasitic bronze-cuckoos. At a macroevolutionary scale, we show that highly virulent brood-parasitic taxa have higher speciation rates and are more likely to speciate in sympatry than less-virulent and nonparasitic relatives. We reveal the microevolutionary process underlying speciation: Hosts reject cuckoo nestlings, which selects for mimetic cuckoo nestling morphology. Where cuckoos exploit multiple hosts, selection for mimicry drives genetic and phenotypic divergence corresponding to host preference, even in sympatry. Our work elucidates perhaps the most common, but poorly characterized, evolutionary process driving biological diversification.
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Affiliation(s)
- N E Langmore
- Research School of Biology, Australian National University, Canberra, Australia
| | - A Grealy
- Research School of Biology, Australian National University, Canberra, Australia
- Australian National Wildlife Collection, National Research Collections Australia, CSIRO, Canberra, Australia
| | - H-J Noh
- Research School of Biology, Australian National University, Canberra, Australia
| | - I Medina
- School of Biosciences, The University of Melbourne, Melbourne, Australia
| | - A Skeels
- Research School of Biology, Australian National University, Canberra, Australia
| | - J Grant
- Research School of Biology, Australian National University, Canberra, Australia
| | - K D Murray
- Research School of Biology, Australian National University, Canberra, Australia
| | - R M Kilner
- Department of Zoology, University of Cambridge, Cambridge, UK
| | - C E Holleley
- Australian National Wildlife Collection, National Research Collections Australia, CSIRO, Canberra, Australia
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2
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Hite JL, Pfenning-Butterworth A, Auld SKJR. Commentary: Infectious disease — the ecological theater and the evolutionary play. Evol Ecol 2023. [DOI: 10.1007/s10682-023-10229-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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3
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Buckingham LJ, Ashby B. Coevolutionary theory of hosts and parasites. J Evol Biol 2022; 35:205-224. [PMID: 35030276 PMCID: PMC9305583 DOI: 10.1111/jeb.13981] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 12/14/2021] [Accepted: 01/05/2022] [Indexed: 11/30/2022]
Abstract
Host and parasite evolution are closely intertwined, with selection for adaptations and counter‐adaptations forming a coevolutionary feedback loop. Coevolutionary dynamics are often difficult to intuit due to these feedbacks and are hard to demonstrate empirically in most systems. Theoretical models have therefore played a crucial role in shaping our understanding of host–parasite coevolution. Theoretical models vary widely in their assumptions, approaches and aims, and such variety makes it difficult, especially for non‐theoreticians and those new to the field, to: (1) understand how model approaches relate to one another; (2) identify key modelling assumptions; (3) determine how model assumptions relate to biological systems; and (4) reconcile the results of different models with contrasting assumptions. In this review, we identify important model features, highlight key results and predictions and describe how these pertain to model assumptions. We carry out a literature survey of theoretical studies published since the 1950s (n = 219 papers) to support our analysis. We identify two particularly important features of models that tend to have a significant qualitative impact on the outcome of host–parasite coevolution: population dynamics and the genetic basis of infection. We also highlight the importance of other modelling features, such as stochasticity and whether time proceeds continuously or in discrete steps, that have received less attention but can drastically alter coevolutionary dynamics. We finish by summarizing recent developments in the field, specifically the trend towards greater model complexity, and discuss likely future directions for research.
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Affiliation(s)
- Lydia J Buckingham
- Department of Mathematical Sciences, University of Bath, Bath, UK, BA2 7AY.,Milner Centre for Evolution, University of Bath, Bath, UK, BA2 7AY
| | - Ben Ashby
- Department of Mathematical Sciences, University of Bath, Bath, UK, BA2 7AY.,Milner Centre for Evolution, University of Bath, Bath, UK, BA2 7AY
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4
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Maisonneuve L, Beneteau T, Joron M, Smadi C, Llaurens V. When Do Opposites Attract? A Model Uncovering the Evolution of Disassortative Mating. Am Nat 2021; 198:625-641. [PMID: 34648401 DOI: 10.1086/716509] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AbstractDisassortative mating is a rare form of mate preference that promotes the persistence of polymorphism. While the evolution of assortative mating and its consequences for trait variation and speciation have been extensively studied, the conditions enabling the evolution of disassortative mating are still poorly understood. Mate preferences increase the risk of missing mating opportunities, a cost that can be compensated by a greater fitness of offspring. Heterozygote advantage should therefore promote the evolution of disassortative mating, which maximizes the number of heterozygous offspring. From the analysis of a two-locus diploid model with one locus controlling the mating cue under viability selection and the other locus coding for the level of disassortative preference, we show that heterozygote advantage and negative frequency-dependent viability selection acting at the cue locus promote the evolution of disassortative preferences. We predict conditions of evolution of disassortative mating coherent with selection regimes acting on traits observed in the wild. We also show that disassortative mating generates sexual selection, which disadvantages heterozygotes at the cue locus, limiting the evolution of disassortative preferences. Altogether, our results partially explain why this behavior is rare in natural populations.
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5
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Hund AK, Hubbard JK, Albrecht T, Vortman Y, Munclinger P, Krausová S, Tomášek O, Safran RJ. Divergent sexual signals reflect costs of local parasites. Evolution 2020; 74:2404-2418. [PMID: 32385910 DOI: 10.1111/evo.13994] [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: 12/26/2019] [Revised: 04/12/2020] [Accepted: 04/26/2020] [Indexed: 01/27/2023]
Abstract
Many closely related populations are distinguished by variation in sexual signals and this variation is hypothesized to play an important role in reproductive isolation and speciation. Within populations, there is considerable evidence that sexual signals provide information about the incidence and severity of parasite infections, but it remains unclear if variation in parasite communities across space could play a role in initiating or maintaining sexual trait divergence. To test for variation in parasite-associated selection, we compared three barn swallow subspecies with divergent sexual signals. We found that parasite community structure and host tolerance to ecologically similar parasites varied between subspecies. Across subspecies we also found that different parasites were costly in terms of male survival and reproductive success. For each subspecies, the preferred sexual signal(s) were associated with the most costly local parasite(s), indicating that divergent signals are providing relevant information to females about local parasite communities. Across subspecies, the same traits were often associated with different parasites, indicating that parasite-sexual signal links are quite flexible and may evolve relatively quickly. This study provides evidence for (1) variation in parasite communities and (2) different parasite-sexual signal links among three closely related subspecies with divergent sexual signal traits, suggesting that parasites may play an important role in initiating and/or maintaining the divergence of sexual signals among these closely related, yet geographically isolated populations.
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Affiliation(s)
- Amanda K Hund
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado, 80309.,Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, Minnesota, 55108
| | - Joanna K Hubbard
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado, 80309.,Department of Biology, Truman State University, Kirksville, Missouri, 63501
| | - Tomáš Albrecht
- Institute of Vertebrate Biology, Czech Academy of Sciences, Brno, 60365, Czech Republic.,Department of Zoology, Faculty of Science, Charles University, Prague, 128 44, Czech Republic
| | - Yoni Vortman
- Department of Animal Sciences, Tel Hai Academic College, Upper Galilee, 1220800, Israel
| | - Pavel Munclinger
- Department of Zoology, Faculty of Science, Charles University, Prague, 128 44, Czech Republic
| | - Simona Krausová
- Department of Zoology, Faculty of Science, Charles University, Prague, 128 44, Czech Republic
| | - Oldřich Tomášek
- Institute of Vertebrate Biology, Czech Academy of Sciences, Brno, 60365, Czech Republic
| | - Rebecca J Safran
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado, 80309
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6
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Govaert L, Fronhofer EA, Lion S, Eizaguirre C, Bonte D, Egas M, Hendry AP, De Brito Martins A, Melián CJ, Raeymaekers JAM, Ratikainen II, Saether B, Schweitzer JA, Matthews B. Eco‐evolutionary feedbacks—Theoretical models and perspectives. Funct Ecol 2018. [DOI: 10.1111/1365-2435.13241] [Citation(s) in RCA: 92] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Lynn Govaert
- Laboratory of Aquatic Ecology, Evolution and Conservation KU Leuven Leuven Belgium
- Department of Aquatic Ecology Eawag: Swiss Federal Institute of Aquatic Science and Technology Dübendorf Switzerland
- Department of Evolutionary Biology and Environmental Studies University of Zurich Zürich Switzerland
| | | | - Sébastien Lion
- Centre d'Ecologie Fonctionnelle et Evolutive CNRS, IRD, EPHE Université de Montpellier Montpellier France
| | | | - Dries Bonte
- Department of Biology Ghent University Ghent Belgium
| | - Martijn Egas
- Institute for Biodiversity and Ecosystem Dynamics University of Amsterdam Amsterdam The Netherlands
| | - Andrew P. Hendry
- Redpath Museum and Department of Biology McGill University Montreal Quebec Canada
| | - Ayana De Brito Martins
- Fish Ecology and Evolution DepartmentCenter for Ecology, Evolution and BiogeochemistryEawag: Swiss Federal Institute of Aquatic Science and Technology Dübendorf Switzerland
| | - Carlos J. Melián
- Fish Ecology and Evolution DepartmentCenter for Ecology, Evolution and BiogeochemistryEawag: Swiss Federal Institute of Aquatic Science and Technology Dübendorf Switzerland
| | | | - Irja I. Ratikainen
- Department of Biology Centre for Biodiversity Dynamics Norwegian University of Science and Technology Trondheim Norway
- Institute of Biodiversity, Animal Health and Comparative Medicine University of Glasgow Glasgow UK
| | - Bernt‐Erik Saether
- Department of Biology Centre for Biodiversity Dynamics Norwegian University of Science and Technology Trondheim Norway
| | - Jennifer A. Schweitzer
- Department of Ecology and Evolutionary Biology University of Tennessee Knoxville Tennessee
| | - Blake Matthews
- Department of Aquatic Ecology Eawag: Swiss Federal Institute of Aquatic Science and Technology Dübendorf Switzerland
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7
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Brandies PA, Grueber CE, Ivy JA, Hogg CJ, Belov K. Disentangling the mechanisms of mate choice in a captive koala population. PeerJ 2018; 6:e5438. [PMID: 30155356 PMCID: PMC6108315 DOI: 10.7717/peerj.5438] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 07/23/2018] [Indexed: 11/29/2022] Open
Abstract
Successful captive breeding programs are crucial to the long-term survival of many threatened species. However, pair incompatibility (breeding failure) limits sustainability of many captive populations. Understanding whether the drivers of this incompatibility are behavioral, genetic, or a combination of both, is crucial to improving breeding programs. We used 28 years of pairing data from the San Diego Zoo koala colony, plus genetic analyses using both major histocompatibility complex (MHC)-linked and non-MHC-linked microsatellite markers, to show that both genetic and non-genetic factors can influence mating success. Male age was reconfirmed to be a contributing factor to the likelihood of a koala pair copulating. This trend could also be related to a pair's age difference, which was highly correlated with male age in our dataset. Familiarity was reconfirmed to increase the probability of a successful copulation. Our data provided evidence that females select mates based on MHC and genome-wide similarity. Male heterozygosity at MHC class II loci was associated with both pre- and post-copulatory female choice. Genome-wide similarity, and similarity at the MHC class II DAB locus, were also associated with female choice at the post-copulatory level. Finally, certain MHC-linked alleles were associated with either increased or decreased mating success. We predict that utilizing a variety of behavioral and MHC-dependent mate choice mechanisms improves female fitness through increased reproductive success. This study highlights the complexity of mate choice mechanisms in a species, and the importance of ascertaining mate choice mechanisms to improve the success of captive breeding programs.
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Affiliation(s)
- Parice A. Brandies
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
| | - Catherine E. Grueber
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
- San Diego Zoo Global, San Diego, CA, USA
| | | | - Carolyn J. Hogg
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
| | - Katherine Belov
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
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8
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Gibson DJ, Adamowicz SJ, Jacobs SR, Smith MA. Host Specificity in Subarctic Aphids. ENVIRONMENTAL ENTOMOLOGY 2018; 47:77-86. [PMID: 29186477 DOI: 10.1093/ee/nvx176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Plants and herbivorous (or parasitic) insects form the majority of macroscopic life. The specificity of interaction between host plant and parasitic insect depends on the adaptations of both the host and the parasite. Over time, these interactions evolve and change as a result of an 'arms race' between host and parasite, and the resulting species-specific adaptations may be maintained, perpetuating these interactions across speciation events. This can lead to specialisation between species or clades. With speciation and species sorting over time, complex interactions evolve. Here, we elucidate a three-tier method to test these interactions using the aphids (Hemiptera: Aphididae) and plants of Churchill (Manitoba, Canada) as a model system. We analyzed these interactions by testing for three patterns in host specificity: monophagy, phylogenetic clustering, and cophylogeny. We defined monophagy strictly as one species feeding exclusively upon a single host plant species (an association likely driven by arms races in morphology, chemical resistance/tolerance, and visual appearance) and observed this in 7 of 22 aphid species. In all the remaining 'polyphagous' cases, there was a strong trend toward monophagy (80% of individuals were found on a single host plant species). Second, we observed two separate examples of phylogenetic clustering where groups of closely related aphid species fed upon individual plant species. Finally, we found no support for cophylogenetic relationships where both aphids and plants cospeciate to form congruent phylogenetic trees (evidence of coadaptation through an ongoing arms race). One explanation for uncovering species-specific interactions in a recently deglaciated, subarctic locality is that the species involved in the associations moved north together. Testing different levels of specificity in the most predominant species-species interactions on the planet will allow us to elucidate these patterns accurately and gives us insight into where to direct future research.
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Affiliation(s)
- Daniel J Gibson
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
- Churchill Northern Studies Centre, Manitoba, Canada
| | - Sarah J Adamowicz
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
- Biodiversity Institute of Ontario, University of Guelph, Guelph, Ontario, Canada
| | - Shoshanah R Jacobs
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
| | - M Alex Smith
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
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9
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MacPherson A, Otto SP. Joint coevolutionary-epidemiological models dampen Red Queen cycles and alter conditions for epidemics. Theor Popul Biol 2017; 122:137-148. [PMID: 29289520 DOI: 10.1016/j.tpb.2017.12.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 11/30/2017] [Accepted: 12/12/2017] [Indexed: 11/18/2022]
Abstract
Host-parasite interactions in the form of infectious diseases are a topic of interest in both evolutionary biology and public health. Both fields have relied on mathematical models to predict and understand the dynamics and consequences of these interactions. Yet few models explicitly incorporate both epidemiological and coevolutionary dynamics, allowing for genetic variation in both hosts and parasites. By comparing a matching-alleles model of coevolution, a susceptible-infected-recovered-susceptible compartmental model from epidemiology, and a combined coevolutionary-epidemiology model we assess the effect of the coevolutionary feedback on the epidemiological dynamics and vice versa. We find that Red-Queen cycles are not robust in an epidemiological framework and that coevolutionary interactions can alter the conditions under which epidemic cycles arise. Incorporating both explicit epidemiology and genetic diversity may have important implications for the maintenance of sexual reproduction as well as disease management.
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Affiliation(s)
- Ailene MacPherson
- Department of Zoology & Biodiversity Research Centre, University of British Columbia, Vancouver, BC, Canada V6T 1Z4.
| | - Sarah P Otto
- Department of Zoology & Biodiversity Research Centre, University of British Columbia, Vancouver, BC, Canada V6T 1Z4.
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10
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Nuismer SL. Rethinking Conventional Wisdom: Are Locally Adapted Parasites Ahead in the Coevolutionary Race? Am Nat 2017; 190:584-593. [PMID: 28937821 DOI: 10.1086/693455] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The metaphors of the Red Queen and the arms race have inspired a large amount of research aimed at understanding the process of antagonistic coevolution between hosts and parasites. One approach that has been heavily used is to estimate the strength of parasite local adaptation using a reciprocal cross infection or transplant study. These studies frequently conclude that the locally adapted species is ahead in the coevolutionary race. Here, I use mathematical models to decompose parasite infectivity into components attributable to local versus global adaptation and to develop a robust index of which species is ahead in the coevolutionary race, which I term coevolutionary advantage. Computer simulations of coevolving host-parasite interactions demonstrate that because the magnitudes of local and global adaptation are largely independent, the link between the sign of local adaptation and coevolutionary advantage is tenuous. A consequence of the weak coupling between local adaptation and coevolutionary advantage is that the bulk of existing empirical studies do not sample enough populations for any reliable conclusions to be drawn. Together, these results suggest that the long-standing conventional wisdom holding that locally adapted parasites are ahead in the coevolutionary race should be reconsidered.
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11
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Botto-Mahan C, Campos V, Medel R. Sex-dependent infection causes nonadditive effects on kissing bug fecundity. Ecol Evol 2017; 7:3552-3557. [PMID: 28515890 PMCID: PMC5433981 DOI: 10.1002/ece3.2956] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 03/14/2017] [Indexed: 11/28/2022] Open
Abstract
The influence of parasites on host reproduction has been widely studied in natural and experimental conditions. Most studies, however, have evaluated the parasite impact on female hosts only, neglecting the contribution of males for host reproduction. This omission is unfortunate as sex‐dependent infection may have important implications for host–parasite associations. Here, we evaluate for the first time the independent and nonindependent effects of gender infection on host reproductive success using the kissing bug Mepraia spinolai and the protozoan Trypanosoma cruzi as model system. We set up four crossing treatments including the following: (1) both genders infected, (2) both genders uninfected, (3) males infected—females uninfected, and (4) males uninfected—females infected, using fecundity measures as response variables. Interactive effects of infection between sexes were prevalent. Uninfected females produced more and heavier eggs when crossed with uninfected than infected males. Uninfected males, in turn, sired more eggs and nymphs when crossed with uninfected than infected females. Unexpectedly, infected males sired more nymphs when crossed with infected than uninfected females. These results can be explained by the effect of parasitism on host body size. As infection reduced size in both genders, infection on one sex only creates body size mismatches and mating constraints that are not present in pairs with the same infection status. Our results indicate the fitness impact of parasitism was contingent on the infection status of genders and mediated by body size. As the fecundity impact of parasitism cannot be estimated independently for each gender, inferences based only on female host infection run the risk of providing biased estimates of parasite‐mediated impact on host reproduction.
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Affiliation(s)
- Carezza Botto-Mahan
- Departamento de Ciencias Ecológicas Facultad de Ciencias Universidad de Chile Santiago Chile
| | - Verónica Campos
- Department of Entomology Purdue University West Lafayette IN USA
| | - Rodrigo Medel
- Departamento de Ciencias Ecológicas Facultad de Ciencias Universidad de Chile Santiago Chile
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12
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Campbell LJ, Head ML, Wilfert L, Griffiths AGF. An ecological role for assortative mating under infection? CONSERV GENET 2017; 18:983-994. [PMID: 32009857 PMCID: PMC6961493 DOI: 10.1007/s10592-017-0951-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 03/01/2017] [Indexed: 11/29/2022]
Abstract
Wildlife diseases are emerging at a higher rate than ever before meaning that understanding their potential impacts is essential, especially for those species and populations that may already be of conservation concern. The link between population genetic structure and the resistance of populations to disease is well understood: high genetic diversity allows populations to better cope with environmental changes, including the outbreak of novel diseases. Perhaps following this common wisdom, numerous empirical and theoretical studies have investigated the link between disease and disassortative mating patterns, which can increase genetic diversity. Few however have looked at the possible link between disease and the establishment of assortative mating patterns. Given that assortative mating can reduce genetic variation within a population thus reducing the adaptive potential and long-term viability of populations, we suggest that this link deserves greater attention, particularly in those species already threatened by a lack of genetic diversity. Here, we summarise the potential broad scale genetic implications of assortative mating patterns and outline how infection by pathogens or parasites might bring them about. We include a review of the empirical literature pertaining to disease-induced assortative mating. We also suggest future directions and methodological improvements that could advance our understanding of how the link between disease and mating patterns influences genetic variation and long-term population viability.
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Affiliation(s)
- L. J. Campbell
- Environment and Sustainability Institute, University of Exeter, Penryn Campus, Penryn, Cornwall TR10 9FE UK
- Institute of Zoology, Zoological Society of London, Regent’s Park, London, NW1 4RY UK
| | - M. L. Head
- Division of Evolution, Ecology and Genetics, Research School of Biology, Australian National University, Canberra, ACT Australia
| | - L. Wilfert
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn, Cornwall TR10 9FE UK
| | - A. G. F. Griffiths
- Environment and Sustainability Institute, University of Exeter, Penryn Campus, Penryn, Cornwall TR10 9FE UK
- FoAM Kernow, Studio E, Jubilee Warehouse, Commercial Road, Penryn, Cornwall TR10 8FG UK
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13
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Brunner FS, Eizaguirre C. Can environmental change affect host/parasite-mediated speciation? ZOOLOGY 2016; 119:384-94. [PMID: 27210289 DOI: 10.1016/j.zool.2016.04.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 02/16/2016] [Accepted: 04/13/2016] [Indexed: 12/21/2022]
Abstract
Parasitism can be a driver of species divergence and thereby significantly alter species formation processes. While we still need to better understand how parasite-mediated speciation functions, it is even less clear how this process is affected by environmental change. Both rapid and gradual changes of the environment can modify host immune responses, parasite virulence and the specificity of their interactions. They will thereby change host-parasite evolutionary trajectories and the potential for speciation in both hosts and parasites. Here, we summarise mechanisms of host-parasite interactions affecting speciation and subsequently consider their susceptibility to environmental changes. We mainly focus on the effects of temperature change and nutrient input to ecosystems as they are major environmental stressors. There is evidence for both disruptive and accelerating effects of those pressures on speciation that seem to be context-dependent. A prerequisite for parasite-driven host speciation is that parasites significantly alter the host's Darwinian fitness. This can rapidly lead to divergent selection and genetic adaptation; however, it is likely preceded by more short-term plastic and transgenerational effects. Here, we also consider how these first responses and their susceptibility to environmental changes could lead to alterations of the species formation process and may provide alternative pathways to speciation.
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Affiliation(s)
- Franziska S Brunner
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, United Kingdom.
| | - Christophe Eizaguirre
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, United Kingdom
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14
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Kawatsu K. Red Queen dancing in the lek: effects of mating skew on host-parasite interactions. Ecol Evol 2015; 5:5432-5440. [PMID: 30151144 PMCID: PMC6102524 DOI: 10.1002/ece3.1809] [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: 06/05/2015] [Revised: 09/30/2015] [Accepted: 10/02/2015] [Indexed: 11/28/2022] Open
Abstract
The RQH (Red Queen hypothesis), which argues that hosts need to be continuously finding new ways to avoid parasites that are able to infect common host genotypes, has been at the center of discussions on the maintenance of sex. This is because diversity is favored under the host–parasite coevolution based on negative frequency‐dependent selection, and sexual reproduction is a mechanism that generates genetic diversity in the host population. Together with parasite infections, sexual organisms are usually under sexual selection, which leads to mating skew or mating success biased toward males with a particular phenotype. Thus, strong mating skew would affect genetic variance in a population and should affect the benefit of the RQH. However, most models have investigated the RQH under a random mating system and not under mating skew. In this study, I show that sexual selection and the resultant mating skew may increase parasite load in the hosts. An IBM (individual‐based model), which included host–parasite interactions and sexual selection among hosts, demonstrates that mating skew influenced parasite infection in the hosts under various conditions. Moreover, the IBM showed that the mating skew evolves easily in cases of male–male competition and female mate choice, even though it imposes an increased risk of parasite infection on the hosts. These findings indicated that whether the RQH favored sexual reproduction depended on the condition of mating skew. That is, consideration of the host mating system would provide further understanding of conditions in which the RQH favors sexual reproduction in real organisms.
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Affiliation(s)
- Kazutaka Kawatsu
- Department of Environmental Solution Technology Faculty of Science and Technology Ryukoku University 1-5 Yokotani Seta Oe-cho Otsu Shiga 520-2194 Japan
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15
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Stutz WE, Schmerer M, Coates JL, Bolnick DI. Among-lake reciprocal transplants induce convergent expression of immune genes in threespine stickleback. Mol Ecol 2015; 24:4629-46. [PMID: 26118468 DOI: 10.1111/mec.13295] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 06/22/2015] [Accepted: 06/24/2015] [Indexed: 12/25/2022]
Abstract
Geographic variation in parasite communities can drive evolutionary divergence in host immune genes. However, biotic and abiotic environmental variation can also induce plastic differences in immune function among populations. At present, there is little information concerning the relative magnitudes of heritable vs. induced immune divergence in natural populations. We examined immune gene expression profiles of threespine stickleback (Gasterosteus aculeatus) from six lakes on Vancouver Island, British Columbia. Parasite community composition differs between lake types (large or small, containing limnetic- or benthic-like stickleback) and between watersheds. We observed corresponding differences in immune gene expression profiles among wild-caught stickleback, using a set of seven immune genes representing distinct branches of the immune system. To evaluate the role of environmental effects on this differentiation, we experimentally transplanted wild-caught fish into cages in their native lake, or into a nearby foreign lake. Transplanted individuals' immune gene expression converged on patterns typical of their destination lake, deviating from their native expression profile. Transplant individuals' source population had a much smaller effect, suggesting relatively weak genetic underpinning of population differences in immunity, as viewed through gene expression. This strong environmental regulation of immune gene expression provides a counterpoint to the large emerging literature documenting microevolution and genetic diversification of immune function. Our findings illustrate the value of studying immunity in natural environmental settings where the immune system has evolved and actively functions.
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Affiliation(s)
- William E Stutz
- Department of Integrative Biology, University of Texas at Austin, One University Station C0990, Austin, TX, 78712, USA
| | - Matthew Schmerer
- Department of Integrative Biology, University of Texas at Austin, One University Station C0990, Austin, TX, 78712, USA
| | - Jessica L Coates
- Department of Biology, Spelman College, 350 Spelman Lane SW, Atlanta, GA, 30314, USA
| | - Daniel I Bolnick
- Department of Integrative Biology, University of Texas at Austin, One University Station C0990, Austin, TX, 78712, USA.,Howard Hughes Medical Institute, University of Texas at Austin, One University Station C0990, Austin, TX, 78712, USA
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Sommer S, Rakotondranary SJ, Ganzhorn JU. Maintaining microendemic primate species along an environmental gradient - parasites as drivers for species differentiation. Ecol Evol 2014; 4:4751-65. [PMID: 25558366 PMCID: PMC4278824 DOI: 10.1002/ece3.1311] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 10/10/2014] [Accepted: 10/10/2014] [Indexed: 11/07/2022] Open
Abstract
Understanding the drivers of species adaptations to changing environments on the one hand and the limits for hybridization on the other hand is among the hottest questions in evolutionary biology. Parasites represent one of the major selective forces driving host evolution and at least those with free-living stages are at the same time dependent on the ecological conditions of their host's habitat. Local immunological adaptations of host species to varying parasite pressure are therefore expected and might represent the genetic basis for ecological speciation and the maintenance of recently diverged species. Madagascar provides one of the rare examples where two partially sympatric primate species (Microcebus griseorufus, M. murinus) and their hybrids, as well as an allopatric species (M. cf rufus) live in close proximity along a very steep environmental gradient ranging from southern dry spiny bush to gallery forest to evergreen eastern humid rain forest, thus mimicking the situation encountered during extensions and retreats of vegetation formations under changing climatic conditions. This system was used to study parasite infection and immune gene (MHC) adaptations to varying parasite pressure that might provide selective advantages to pure species over hybrids. Parasite burdens increased with increasing humidity. M. griseorufus, M. murinus, and their hybrids but not M. rufus shared the same MHC alleles, indicating either retention of ancestral polymorphism or recent gene flow. The hybrids had much higher prevalence of intestinal parasites than either of the parent species living under identical environmental conditions. The different representation of parasites can indicate a handicap for hybrids that maintains species identities.
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Affiliation(s)
- Simone Sommer
- Evolutionary Genetics, Leibniz-Institute for Zoo- and Wildlife ResearchAlfred-Kowalke-Strasse 10, Berlin, 10315, Germany
- Institute for Experimental Ecology, University of UlmAlbert-Einstein Allee 11, Ulm, 89069, Germany
| | - Solofomalla Jacques Rakotondranary
- Department of Animal Ecology and Conservation, University of Hamburg, Biozentrum GrindelMartin-Luther-King Platz 3, Hamburg, 20146, Germany
| | - Jörg U Ganzhorn
- Department of Animal Ecology and Conservation, University of Hamburg, Biozentrum GrindelMartin-Luther-King Platz 3, Hamburg, 20146, Germany
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Greenspoon PB, M'Gonigle LK. Host-parasite interactions and the evolution of nonrandom mating. Evolution 2014; 68:3570-80. [PMID: 25314225 DOI: 10.1111/evo.12538] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Accepted: 08/13/2014] [Indexed: 01/01/2023]
Abstract
Some species mate nonrandomly with respect to alleles underlying immunity. One hypothesis proposes that this is advantageous because nonrandom mating can lead to offspring with superior parasite resistance. We investigate this hypothesis, generalizing previous models in four ways: First, rather than only examining invasibility of modifiers of nonrandom mating, we identify evolutionarily stable strategies. Second, we study coevolution of both haploid and diploid hosts and parasites. Third, we allow for maternal parasite transmission. Fourth, we allow for many alleles at the interaction locus. We find that evolutionarily stable rates of assortative or disassortative mating are usually near zero or one. However, for one case, in which assumptions most closely match the major histocompatibility complex (MHC) system, intermediate rates of disassortative mating can evolve. Across all cases, with haploid hosts, evolution proceeds toward complete disassortative mating, whereas with diploid hosts either assortative or disassortative mating can evolve. Evolution of nonrandom mating is much less affected by the ploidy of parasites. For the MHC case, maternal transmission of parasites, because it creates an advantage to producing offspring that differ from their parents, leads to higher evolutionarily stable rates of disassortative mating. Lastly, with more alleles at the interaction locus, disassortative mating evolves to higher levels.
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18
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Abstract
Coevolution, reciprocal adaptation between two or more taxa, is commonly invoked as a primary mechanism responsible for generating much of Earth's biodiversity. This conceptually appealing hypothesis is incredibly broad in evolutionary scope, encompassing diverse patterns and processes operating over timescales ranging from microbial generations to geological eras. However, we have surprisingly little evidence that large-scale associations between coevolution and diversity reflect a causal relationship at smaller timescales, in which coevolutionary selection is directly responsible for the formation of new species. In this synthesis, we critically evaluate evidence for the often-invoked hypothesis that coevolution is an important process promoting biological diversification. We conclude that the lack of widespread evidence for coevolutionary diversification may be best explained by the fact that coevolution's importance in diversification varies depending on the type of interaction and the scale of the diversification under consideration.
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Affiliation(s)
- David H Hembry
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, California 94720
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Dybdahl MF, Jenkins CE, Nuismer SL. Identifying the Molecular Basis of Host-Parasite Coevolution: Merging Models and Mechanisms. Am Nat 2014; 184:1-13. [DOI: 10.1086/676591] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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20
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Testing for coevolutionary diversification: linking pattern with process. Trends Ecol Evol 2013; 29:82-9. [PMID: 24314843 DOI: 10.1016/j.tree.2013.11.003] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Revised: 11/05/2013] [Accepted: 11/07/2013] [Indexed: 11/24/2022]
Abstract
Coevolutionary diversification is cited as a major mechanism driving the evolution of diversity, particularly in plants and insects. However, tests of coevolutionary diversification have focused on elucidating macroevolutionary patterns rather than the processes giving rise to such patterns. Hence, there is weak evidence that coevolution promotes diversification. This is in part due to a lack of understanding about the mechanisms by which coevolution can cause speciation and the difficulty of integrating results across micro- and macroevolutionary scales. In this review, we highlight potential mechanisms of coevolutionary diversification, outline approaches to examine this process across temporal scales, and propose a set of minimal requirements for demonstrating coevolutionary diversification. Our aim is to stimulate research that tests more rigorously for coevolutionary diversification.
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Gibert JP, Pires MM, Thompson JN, Guimarães PR. The spatial structure of antagonistic species affects coevolution in predictable ways. Am Nat 2013; 182:578-91. [PMID: 24107366 DOI: 10.1086/673257] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
A current challenge in evolutionary ecology is to assess how the spatial structure of interacting species shapes coevolution. Previous work on the geographic mosaic of coevolution has shown that coevolution depends on the spatial structure, the strength of selection, and gene flow across populations. We used spatial subgraphs and coevolutionary models to evaluate how spatial structure and the location of coevolutionary hotspots (sites in which reciprocal selection occurs) and coldspots (sites in which unidirectional selection occurs) contribute to the dynamics of coevolution and the maintenance of polymorphisms. Specifically, we developed a new approach based on the Laplacian matrices of spatial subgraphs to explore the tendency of interacting species to evolve toward stable polymorphisms. Despite the complex interplay between gene flow and the strength of reciprocal selection, simple rules drive coevolution in small groups of spatially structured interacting populations. Hotspot location and the spatial organization of coldspots are crucial for understanding patterns in the maintenance of polymorphisms. Moreover, the degree of spatial variation in the outcomes of the coevolutionary process can be predicted from the network pattern of gene flow among sites. Our work provides us with novel tools that can be used in the field or the laboratory to predict the effects of spatial structure on coevolutionary trajectories.
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Affiliation(s)
- Jean P Gibert
- Laboratorio de Paleobiología, Sección Paleontología, Facultad de Ciencias de la Universidad de la República, Iguá 4225, Montevideo 11400, Uruguay
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Nuismer SL, Jordano P, Bascompte J. COEVOLUTION AND THE ARCHITECTURE OF MUTUALISTIC NETWORKS. Evolution 2012; 67:338-54. [DOI: 10.1111/j.1558-5646.2012.01801.x] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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The Role of Parasitism in Adaptive Radiations—When Might Parasites Promote and When Might They Constrain Ecological Speciation? INTERNATIONAL JOURNAL OF ECOLOGY 2012. [DOI: 10.1155/2012/280169] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Research on speciation and adaptive radiation has flourished during the past decades, yet factors underlying initiation of reproductive isolation often remain unknown. Parasites represent important selective agents and have received renewed attention in speciation research. We review the literature on parasite-mediated divergent selection in context of ecological speciation and present empirical evidence for three nonexclusive mechanisms by which parasites might facilitate speciation: reduced viability or fecundity of immigrants and hybrids, assortative mating as a pleiotropic by-product of host adaptation, and ecologically-based sexual selection. We emphasise the lack of research on speciation continuums, which is why no study has yet made a convincing case for parasite driven divergent evolution to initiate the emergence of reproductive isolation. We also point interest towards selection imposed by single versus multiple parasite species, conceptually linking this to strength and multifariousness of selection. Moreover, we discuss how parasites, by manipulating behaviour or impairing sensory abilities of hosts, may change the form of selection that underlies speciation. We conclude that future studies should consider host populations at variable stages of the speciation process, and explore recurrent patterns of parasitism and resistance that could pinpoint the role of parasites in imposing the divergent selection that initiates ecological speciation.
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Eizaguirre C, Lenz TL. Major histocompatibility complex polymorphism: dynamics and consequences of parasite-mediated local adaptation in fishes. JOURNAL OF FISH BIOLOGY 2010; 77:2023-2047. [PMID: 21133915 DOI: 10.1111/j.1095-8649.2010.02819.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Parasitism is a common form of life and represents a strong selective pressure for host organisms. In response to this evolutionary pressure, vertebrates have developed genetically coded defences such as the major histocompatibility complex (MHC). Mechanisms of parasite-mediated selection not only maintain outstanding polymorphism in these genes but have also been proposed to further promote host population divergence and ultimately speciation because it can drive evolution of local adaptation in which MHC genes play a crucial role. This review first highlights the dynamics and complexity of parasite-mediated selection in natural systems, which not only depends on dominating parasite strategies and on the taxonomic diversity of the parasite community but also includes the differences in parasite communities between habitats and niches, creating divergent selection on locally adapted populations. Then the different ways in which MHC genes potentially allow vertebrates to respond to these dynamics and to adapt locally are outlined. Finally, it is proposed that varying selection strength in time and space may lead to variation in the strength of precopulatory reproductive isolation which has evolved to maintain local adaptation.
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Affiliation(s)
- C Eizaguirre
- Leibniz Institute for Marine Sciences (IFM GEOMAR), Department of Evolutionary Ecology of Marine Fishes, Düsternbrooker Weg 20, 24105, Kiel, Germany.
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Matthews B, Harmon LJ, M'Gonigle L, Marchinko KB, Schaschl H. Sympatric and allopatric divergence of MHC genes in threespine stickleback. PLoS One 2010; 5:e10948. [PMID: 20585386 PMCID: PMC2886830 DOI: 10.1371/journal.pone.0010948] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2010] [Accepted: 04/30/2010] [Indexed: 11/19/2022] Open
Abstract
Parasites can strongly affect the evolution of their hosts, but their effects on host diversification are less clear. In theory, contrasting parasite communities in different foraging habitats could generate divergent selection on hosts and promote ecological speciation. Immune systems are costly to maintain, adaptable, and an important component of individual fitness. As a result, immune system genes, such as those of the Major Histocompatibility Complex (MHC), can change rapidly in response to parasite-mediated selection. In threespine stickleback (Gasterosteus aculeatus), as well as in other vertebrates, MHC genes have been linked with female mating preference, suggesting that divergent selection acting on MHC genes might influence speciation. Here, we examined genetic variation at MHC Class II loci of sticklebacks from two lakes with a limnetic and benthic species pair, and two lakes with a single species. In both lakes with species pairs, limnetics and benthics differed in their composition of MHC alleles, and limnetics had fewer MHC alleles per individual than benthics. Similar to the limnetics, the allopatric population with a pelagic phenotype had few MHC alleles per individual, suggesting a correlation between MHC genotype and foraging habitat. Using a simulation model we show that the diversity and composition of MHC alleles in a sympatric species pair depends on the amount of assortative mating and on the strength of parasite-mediated selection in adjacent foraging habitats. Our results indicate parallel divergence in the number of MHC alleles between sympatric stickleback species, possibly resulting from the contrasting parasite communities in littoral and pelagic habitats of lakes.
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Affiliation(s)
- Blake Matthews
- Aquatic Ecology Department, Swiss Federal Institute of Aquatic Science and Technology (EAWAG), Kastanienbaum, Switzerland.
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Effect of sexual segregation on host-parasite interaction: model simulation for abomasal parasite dynamics in alpine ibex (Capraibex). Int J Parasitol 2010; 40:1285-93. [PMID: 20430029 DOI: 10.1016/j.ijpara.2010.03.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Revised: 03/08/2010] [Accepted: 03/23/2010] [Indexed: 11/24/2022]
Abstract
We investigated whether sexual segregation might affect parasite transmission and host dynamics, hypothesising that if males are the more heavily infected sex and more responsible for the transmission of parasite infections, female avoidance of males and the space they occupy could reduce infection rates. A mathematical model, simulating the interaction between abomasal parasites and a hypothetical alpine ibex (Capraibex) host population composed of its two sexes, was developed to predict the effect of different degrees of sexual segregation on parasite intensity and on host abundance. The results showed that when females tended to be segregated from males, and males were distributed randomly across space, the impact of parasites was the lowest, resulting in the highest host abundance, with each sex having the lowest parasite intensity. The predicted condition that minimises the impact of parasites in our model was the one closest to that observed in nature where females actively seek out the more segregated sites while males are less selective in their ranging behaviour. The overlapping of field observation with the predicted optimal strategy lends support to our idea that there might be a connection between parasite transmission and sexual segregation. Our simulations provide the biological boundaries of host-parasite interaction needed to determine a parasite-mediated effect on sexual segregation and a formalised null hypothesis against which to test future field experiments.
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Eizaguirre C, Lenz TL, Traulsen A, Milinski M. Speciation accelerated and stabilized by pleiotropic major histocompatibility complex immunogenes. Ecol Lett 2009; 12:5-12. [DOI: 10.1111/j.1461-0248.2008.01247.x] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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30
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Abstract
A long-standing goal in evolutionary biology is to identify the conditions that promote the evolution of reproductive isolation and speciation. The factors promoting sympatric speciation have been of particular interest, both because it is notoriously difficult to prove empirically and because theoretical models have generated conflicting results, depending on the assumptions made. Here, we analyze the conditions under which selection favors the evolution of assortative mating, thereby reducing gene flow between sympatric groups, using a general model of selection, which allows fitness to be frequency dependent. Our analytical results are based on a two-locus diploid model, with one locus altering the trait under selection and the other locus controlling the strength of assortment (a "one-allele" model). Examining both equilibrium and nonequilibrium scenarios, we demonstrate that whenever heterozygotes are less fit, on average, than homozygotes at the trait locus, indirect selection for assortative mating is generated. While costs of assortative mating hinder the evolution of reproductive isolation, they do not prevent it unless they are sufficiently great. Assortative mating that arises because individuals mate within groups (formed in time or space) is most conducive to the evolution of complete assortative mating from random mating. Assortative mating based on female preferences is more restrictive, because the resulting sexual selection can lead to loss of the trait polymorphism and cause the relative fitness of heterozygotes to rise above homozygotes, eliminating the force favoring assortment. When assortative mating is already prevalent, however, sexual selection can itself cause low heterozygous fitness, promoting the evolution of complete reproductive isolation (akin to "reinforcement") regardless of the form of natural selection.
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