1
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Week B, Bradburd G. Host-Parasite Coevolution in Continuous Space Leads to Variation in Local Adaptation across Spatial Scales. Am Nat 2024; 203:43-54. [PMID: 38207142 PMCID: PMC11016188 DOI: 10.1086/727470] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2024]
Abstract
AbstractPrevious host-parasite coevolutionary theory has focused on understanding the determinants of local adaptation using spatially discrete models. However, these studies fall short of describing patterns of host-parasite local adaptation across spatial scales. In contrast, empirical work demonstrates that patterns of adaptation depend on the scale at which they are measured. Here, we propose a mathematical model of host-parasite coevolution in continuous space that naturally leads to a scale-dependent definition of local adaptation. In agreement with empirical research, we find that patterns of adaptation vary across spatial scales. In some cases, not only the magnitude of local adaptation but also the identity of the locally adapted species will depend on the spatial scale at which measurements are taken. Building on our results, we suggest a way to consistently measure parasite local adaptation when continuous space is the driver of cross-scale variation. We also describe a way to test whether continuous space is driving cross-scale variation. Taken together, our results provide a new perspective that can be used to understand empirical observations previously unexplained by theoretical expectations and deepens our understanding of the mechanics of host-parasite local adaptation.
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Affiliation(s)
- Bob Week
- University of Oregon, Eugene, Oregon 97403
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2
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Peters MAE, Mideo N, MacPherson A. The maintenance of genetic diversity under host-parasite coevolution in finite, structured populations. J Evol Biol 2023; 36:1328-1341. [PMID: 37610056 DOI: 10.1111/jeb.14207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 06/12/2023] [Accepted: 06/27/2023] [Indexed: 08/24/2023]
Abstract
As a corollary to the Red Queen hypothesis, host-parasite coevolution has been hypothesized to maintain genetic variation in both species. Recent theoretical work, however, suggests that reciprocal natural selection alone is insufficient to maintain variation at individual loci. As highlighted by our brief review of the theoretical literature, models of host-parasite coevolution often vary along multiple axes (e.g. inclusion of ecological feedbacks or abiotic selection mosaics), complicating a comprehensive understanding of the effects of interacting evolutionary processes on diversity. Here we develop a series of comparable models to explore the effect of interactions between spatial structures and antagonistic coevolution on genetic diversity. Using a matching alleles model in finite populations connected by migration, we find that, in contrast to panmictic populations, coevolution in a spatially structured environment can maintain genetic variation relative to neutral expectations with migration alone. These results demonstrate that geographic structure is essential for understanding the effect of coevolution on biological diversity.
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Affiliation(s)
- Madeline A E Peters
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada
| | - Nicole Mideo
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada
| | - Ailene MacPherson
- Department of Mathematics, Simon Fraser University, Burnaby, British Columbia, Canada
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3
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Best A, Ashby B. How do fluctuating ecological dynamics impact the evolution of hosts and parasites? Philos Trans R Soc Lond B Biol Sci 2023; 378:20220006. [PMID: 36744565 PMCID: PMC9900711 DOI: 10.1098/rstb.2022.0006] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Theoretical models of the evolution of parasites and their hosts have shaped our understanding of infectious disease dynamics for over 40 years. Many theoretical models assume that the underlying ecological dynamics are at equilibrium or constant, yet we know that in a great many systems there are fluctuations in the ecological dynamics owing to a variety of intrinsic or extrinsic factors. Here, we discuss the challenges presented when modelling evolution in systems with fluctuating ecological dynamics and summarize the main approaches that have been developed to study host-parasite evolution in such systems. We provide an in-depth guide to one of the methods by applying it to two worked examples of host evolution that have not previously been studied in the literature: when cycles occur owing to seasonal forcing in competition, and when the presence of a free-living parasite causes cycles, with accompanying interactive Python code provided. We review the findings of studies that have explored host-parasite evolution when ecological dynamics fluctuate, and point to areas of future research. Throughout we stress the importance of feedbacks between the ecological and evolutionary dynamics in driving the outcomes of infectious disease systems. This article is part of the theme issue 'Infectious disease ecology and evolution in a changing world'.
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Affiliation(s)
- A. Best
- School of Mathematics and Statistics, University of Sheffield, Sheffield S3 7RH, UK,Integrative Biology, University of California - Berkeley, Berkeley, CA 94720-5800, USA
| | - B. Ashby
- Department of Mathematics, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6,Department of Mathematics, University of Bath, Bath BA2 7AY, UK
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4
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Yang Y, Ma C, Zu J. Coevolutionary dynamics of host-pathogen interaction with density-dependent mortality. J Math Biol 2022; 85:15. [PMID: 35877051 PMCID: PMC9309463 DOI: 10.1007/s00285-022-01782-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 06/08/2022] [Accepted: 07/05/2022] [Indexed: 12/04/2022]
Abstract
This study explores the coevolutionary dynamics of host-pathogen interaction based on a susceptible-infected population model with density-dependent mortality. We assume that both the host’s resistance and the pathogen’s virulence will adaptively evolve, but there are inevitable costs in terms of host birth rate and disease-related mortality rate. Particularly, it is assumed that both the host resistance and pathogen virulence can affect the transmission rate. By using the approach of adaptive dynamics and numerical simulation, we find that the finally coevolutionary outcome depends on the strength of host-pathogen asymmetric interaction, the curvature of trade-off functions, and the intensity of density-dependent natural mortality. To be specific, firstly, we find that if the strengths of host-pathogen asymmetric interaction and disease-related mortality are relatively weak, or the density-dependent natural mortality is relatively strong, then the host resistance and pathogen virulence will evolve to a continuously stable strategy. However, if the strength of host-pathogen asymmetric interaction and disease-related mortality becomes stronger, then the host resistance and pathogen virulence will evolve periodically. Secondly, we find that if the intensities of both the birth rate trade-off function and the density-dependent natural mortality are relatively weak, but the strength of host-pathogen asymmetric interaction becomes relatively strong, then the evolution of host resistance will have a relatively strongly accelerating benefit, the evolutionary branching of host resistance will first arise. However, if the strength of host-pathogen asymmetric interaction is relatively weak, but the intensity of the trade-off function of disease-related mortality becomes relatively strong, then the evolution of pathogen virulence will have a relatively strongly decelerating cost, and the evolutionary branching of pathogen virulence will first arise. Thirdly, after the evolutionary branching of host resistance and pathogen virulence, we further study the coevolutionary dynamics of two-hosts-one-pathogen interaction and one-host-two-pathogens interaction. We find that if the evolutionary branching of host resistance arises firstly, then the finally evolutionary outcome contains a dimorphic host and a monomorphic pathogen population. If the evolutionary branching of pathogen virulence arises firstly, then the finally evolutionary outcome may contain a monomorphic host and a dimorphic pathogen population.
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Affiliation(s)
- Yantao Yang
- School of Mathematics and Statistics, Xi'an Jiaotong University, Xi'an, 710049, PR China
- College of Mathematics and Computer Science, Yan'an University, Yan'an, 716000, PR China
| | - Chaojing Ma
- School of Mathematics and Statistics, Xi'an Jiaotong University, Xi'an, 710049, PR China
| | - Jian Zu
- School of Mathematics and Statistics, Xi'an Jiaotong University, Xi'an, 710049, PR China.
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5
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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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6
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Albery GF, Sweeny AR, Becker DJ, Bansal S. Fine‐scale spatial patterns of wildlife disease are common and understudied. Funct Ecol 2021. [DOI: 10.1111/1365-2435.13942] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
| | - Amy R. Sweeny
- Institute of Evolutionary Biology University of Edinburgh Edinburgh UK
| | | | - Shweta Bansal
- Department of Biology Georgetown University Washington DC USA
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7
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Wren L, Best A. How Local Interactions Impact the Dynamics of an Epidemic. Bull Math Biol 2021; 83:124. [PMID: 34773169 PMCID: PMC8589636 DOI: 10.1007/s11538-021-00961-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 10/20/2021] [Indexed: 11/01/2022]
Abstract
Susceptible-Infected-Recovered (SIR) models have long formed the basis for exploring epidemiological dynamics in a range of contexts, including infectious disease spread in human populations. Classic SIR models take a mean-field assumption, such that a susceptible individual has an equal chance of catching the disease from any infected individual in the population. In reality, spatial and social structure will drive most instances of disease transmission. Here we explore the impacts of including spatial structure in a simple SIR model. We combine an approximate mathematical model (using a pair approximation) and stochastic simulations to consider the impact of increasingly local interactions on the epidemic. Our key development is to allow not just extremes of 'local' (neighbour-to-neighbour) or 'global' (random) transmission, but all points in between. We find that even medium degrees of local interactions produce epidemics highly similar to those with entirely global interactions, and only once interactions are predominantly local do epidemics become substantially lower and later. We also show how intervention strategies to impose local interactions on a population must be introduced early if significant impacts are to be seen.
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Affiliation(s)
- Lydia Wren
- School of Mathematics and Statistics, University of Sheffield, Sheffield, S3 7RH, UK
| | - Alex Best
- School of Mathematics and Statistics, University of Sheffield, Sheffield, S3 7RH, UK.
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8
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Mullon C, Wakano JY, Ohtsuki H. Coevolutionary dynamics of genetic traits and their long-term extended effects under non-random interactions. J Theor Biol 2021; 525:110750. [PMID: 33957155 DOI: 10.1016/j.jtbi.2021.110750] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 04/25/2021] [Accepted: 04/28/2021] [Indexed: 11/15/2022]
Abstract
Organisms continuously modify their living conditions via extended genetic effects on their environment, microbiome, and in some species culture. These effects can impact the fitness of current but also future conspecifics due to non-genetic transmission via ecological or cultural inheritance. In this case, selection on a gene with extended effects depends on the degree to which current and future genetic relatives are exposed to modified conditions. Here, we detail the selection gradient on a quantitative trait with extended effects in a patch-structured population, when gene flow between patches is limited and ecological inheritance within patches can be biased towards offspring. Such a situation is relevant to understand evolutionary driven changes in individual condition that can be preferentially transmitted from parent to offspring, such as cellular state, micro-environments (e.g., nests), pathogens, microbiome, or culture. Our analysis quantifies how the interaction between limited gene flow and biased ecological inheritance influences the joint evolutionary dynamics of traits together with the conditions they modify, helping understand adaptation via non-genetic modifications. As an illustration, we apply our analysis to a gene-culture coevolution scenario in which genetically-determined learning strategies coevolve with adaptive knowledge. In particular, we show that when social learning is synergistic, selection can favour strategies that generate remarkable levels of knowledge under intermediate levels of both vertical cultural transmission and limited dispersal. More broadly, our theory yields insights into the interplay between genetic and non-genetic inheritance, with implications for how organisms evolve to transform their environments.
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Affiliation(s)
- Charles Mullon
- Department of Ecology and Evolution, University of Lausanne, 1015 Lausanne, Switzerland; Department of Evolutionary Studies of Biosystems, School of Advanced Sciences, SOKENDAI (The Graduate University for Advanced Studies), Shonan Village, Hayama, Kanagawa 240-0193, Japan.
| | - Joe Yuichiro Wakano
- Meiji Institute for Advanced Study of Mathematical Sciences, Nakano, Tokyo 164-8525, Japan
| | - Hisashi Ohtsuki
- Department of Evolutionary Studies of Biosystems, School of Advanced Sciences, SOKENDAI (The Graduate University for Advanced Studies), Shonan Village, Hayama, Kanagawa 240-0193, Japan
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9
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Cantor M, Maldonado‐Chaparro AA, Beck KB, Brandl HB, Carter GG, He P, Hillemann F, Klarevas‐Irby JA, Ogino M, Papageorgiou D, Prox L, Farine DR. The importance of individual‐to‐society feedbacks in animal ecology and evolution. J Anim Ecol 2020; 90:27-44. [DOI: 10.1111/1365-2656.13336] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 08/31/2020] [Indexed: 12/31/2022]
Affiliation(s)
- Maurício Cantor
- Department of Collective Behaviour Max Planck Institute of Animal Behavior Radolfzell Germany
- Department of Biology University of Konstanz Konstanz Germany
- Centre for the Advanced Study of Collective Behaviour University of Konstanz Konstanz Germany
- Departamento de Ecologia e Zoologia Universidade Federal de Santa Catarina Florianópolis Brazil
- Centro de Estudos do Mar Universidade Federal do Paraná Pontal do Paraná Brazil
| | - Adriana A. Maldonado‐Chaparro
- Department of Collective Behaviour Max Planck Institute of Animal Behavior Radolfzell Germany
- Department of Biology University of Konstanz Konstanz Germany
- Centre for the Advanced Study of Collective Behaviour University of Konstanz Konstanz Germany
| | - Kristina B. Beck
- Department of Behavioural Ecology and Evolutionary Genetics Max Planck Institute for Ornithology Seewiesen Germany
| | - Hanja B. Brandl
- Department of Collective Behaviour Max Planck Institute of Animal Behavior Radolfzell Germany
- Department of Biology University of Konstanz Konstanz Germany
- Centre for the Advanced Study of Collective Behaviour University of Konstanz Konstanz Germany
| | - Gerald G. Carter
- Department of Collective Behaviour Max Planck Institute of Animal Behavior Radolfzell Germany
- Department of Evolution, Ecology and Organismal Biology The Ohio State University Columbus OH USA
| | - Peng He
- Department of Collective Behaviour Max Planck Institute of Animal Behavior Radolfzell Germany
- Department of Biology University of Konstanz Konstanz Germany
- Centre for the Advanced Study of Collective Behaviour University of Konstanz Konstanz Germany
| | - Friederike Hillemann
- Edward Grey Institute of Field Ornithology Department of Zoology University of Oxford Oxford UK
| | - James A. Klarevas‐Irby
- Department of Biology University of Konstanz Konstanz Germany
- Centre for the Advanced Study of Collective Behaviour University of Konstanz Konstanz Germany
- Department of Migration Max Planck Institute of Animal Behavior Konstanz Germany
| | - Mina Ogino
- Department of Biology University of Konstanz Konstanz Germany
- Centre for the Advanced Study of Collective Behaviour University of Konstanz Konstanz Germany
| | - Danai Papageorgiou
- Department of Collective Behaviour Max Planck Institute of Animal Behavior Radolfzell Germany
- Department of Biology University of Konstanz Konstanz Germany
- Centre for the Advanced Study of Collective Behaviour University of Konstanz Konstanz Germany
| | - Lea Prox
- Department of Biology University of Konstanz Konstanz Germany
- Department of Sociobiology/Anthropology Johann‐Friedrich‐Blumenbach Institute of Zoology & Anthropology University of Göttingen Göttingen Germany
- Behavioral Ecology & Sociobiology Unit German Primate Center Göttingen Germany
| | - Damien R. Farine
- Department of Collective Behaviour Max Planck Institute of Animal Behavior Radolfzell Germany
- Department of Biology University of Konstanz Konstanz Germany
- Centre for the Advanced Study of Collective Behaviour University of Konstanz Konstanz Germany
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10
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Bartlett LJ, Visher E, Haro Y, Roberts KE, Boots M. The target of selection matters: An established resistance-development-time negative genetic trade-off is not found when selecting on development time. J Evol Biol 2020; 33:1109-1119. [PMID: 32390292 DOI: 10.1111/jeb.13639] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 04/22/2020] [Accepted: 05/02/2020] [Indexed: 11/30/2022]
Abstract
Trade-offs are fundamental to evolutionary outcomes and play a central role in eco-evolutionary theory. They are often examined by experimentally selecting on one life-history trait and looking for negative correlations in other traits. For example, populations of the moth Plodia interpunctella selected to resist viral infection show a life-history cost with longer development times. However, we rarely examine whether the detection of such negative genetic correlations depends on the trait on which we select. Here, we examine a well-characterized negative genotypic trade-off between development time and resistance to viral infection in the moth Plodia interpunctella and test whether selection on a phenotype known to be a cost of resistance (longer development time) leads to the predicted correlated increase in resistance. If there is tight pleiotropic relationship between genes that determine development time and resistance underpinning this trade-off, we might expect increased resistance when we select on longer development time. However, we show that selecting for longer development time in this system selects for reduced resistance when compared to selection for shorter development time. This shows how phenotypes typically characterized by a trade-off can deviate from that trade-off relationship, and suggests little genetic linkage between the genes governing viral resistance and those that determine response to selection on the key life-history trait. Our results are important for both selection strategies in applied biological systems and for evolutionary modelling of host-parasite interactions.
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Affiliation(s)
- Lewis J Bartlett
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn, UK
- Center for the Ecology of Infectious Diseases, University of Georgia, Athens, GA, USA
| | - Elisa Visher
- Department of Integrative Biology, University of California, Berkeley, CA, USA
| | | | - Katherine E Roberts
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn, UK
| | - Mike Boots
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn, UK
- Department of Integrative Biology, University of California, Berkeley, CA, USA
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11
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Ferris C, Wright R, Brockhurst MA, Best A. The evolution of host resistance and parasite infectivity is highest in seasonal resource environments that oscillate at intermediate amplitudes. Proc Biol Sci 2020; 287:20200787. [PMID: 32453992 PMCID: PMC7287369 DOI: 10.1098/rspb.2020.0787] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 05/01/2020] [Indexed: 12/31/2022] Open
Abstract
Seasonal environments vary in their amplitude of oscillation but the effects of this temporal heterogeneity for host-parasite coevolution are poorly understood. Here, we combined mathematical modelling and experimental evolution of a coevolving bacteria-phage interaction to show that the intensity of host-parasite coevolution peaked in environments that oscillate in their resource supply with intermediate amplitude. Our experimentally parameterized mathematical model explains that this pattern is primarily driven by the ecological effects of resource oscillations on host growth rates. Our findings suggest that in host-parasite systems where the host's but not the parasite's population growth dynamics are subject to seasonal forcing, the intensity of coevolution will peak at intermediate amplitudes but be constrained at extreme amplitudes of environmental oscillation.
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Affiliation(s)
- Charlotte Ferris
- School of Mathematics and Statistics, University of Sheffield, Hicks Building, 226 Hounsfield Road, Sheffield S3 7RH, UK
| | - Rosanna Wright
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Michael A. Brockhurst
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
| | - Alex Best
- School of Mathematics and Statistics, University of Sheffield, Hicks Building, 226 Hounsfield Road, Sheffield S3 7RH, UK
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12
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Boëte C, Seston M, Legros M. Strategies of host resistance to pathogens in spatially structured populations: An agent-based evaluation. Theor Popul Biol 2019; 130:170-181. [PMID: 31394115 DOI: 10.1016/j.tpb.2019.07.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 07/23/2019] [Accepted: 07/29/2019] [Indexed: 12/23/2022]
Abstract
There is growing theoretical evidence that spatial structure can affect the ecological and evolutionary outcomes of host-parasite interactions. Locally restricted interactions have been shown in particular to affect host resistance and tolerance. In this study we investigate the evolution of several types of host disease resistance strategies, alone or in combination, in spatially structured populations. We construct a spatially explicit, individual-based stochastic model where hosts and parasites interact with each other in a spatial lattice, and interactions are restricted to a given neighbourhood of varying size. We investigate several host resistance strategies, including constitutive (expressed in all resistant hosts), induced (expressed only upon infection), and combinations thereof. We show that a costly constitutive resistance cannot reach fixation, whereas an inducible resistance strategy may become fixed in the population if the cost remains low, particularly if it impacts host recovery. We also demonstrate that mixed strategies can be maintained in the host population, and that a higher investment in a recovery-boosting inducible resistance allows for a higher investment in a constitutive response. Our simulations reveal that the spatial structure of the population impacts the selection for resistance in a complex fashion. While single strategies of resistance are generally favoured in less structured populations, mixed strategies can sometimes prevail only in highly structured environments, e.g. when combining constitutive and transmission-blocking induced responses Overall these results shed new light on the dynamics of disease resistance in a spatially-structured host-pathogen system, and advance our theoretical understanding of the evolutionary dynamics of disease resistance, a necessary step to elaborate more efficient and sustainable strategies for disease management.
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Affiliation(s)
- Christophe Boëte
- ISEM, Université de Montpellier, CNRS, IRD, EPHE, Montpellier, France.
| | - Morgan Seston
- Unite des Virus Emergents (UVE: Aix-Marseille Univ- IRD 190 - INSERM 1207 - IHU Mediterranée Infection), Marseille, France
| | - Mathieu Legros
- ETH Zürich, Institut für Integrative Biologie, Universitätstrasse 16, 8092 Zürich, Switzerland; CSIRO Agriculture & Food, Canberra, ACT 2601, Australia
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13
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Brown A, Akçay E. Evolution of transmission mode in conditional mutualisms with spatial variation in symbiont quality. Evolution 2018; 73:128-144. [DOI: 10.1111/evo.13656] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 10/23/2018] [Indexed: 12/24/2022]
Affiliation(s)
- Alexandra Brown
- Department of Biology University of Pennsylvania Philadelphia Pennsylvania 19104
| | - Erol Akçay
- Department of Biology University of Pennsylvania Philadelphia Pennsylvania 19104
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14
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Bartlett LJ, Wilfert L, Boots M. A genotypic trade-off between constitutive resistance to viral infection and host growth rate. Evolution 2018; 72:2749-2757. [PMID: 30298913 PMCID: PMC6492093 DOI: 10.1111/evo.13623] [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: 07/23/2018] [Accepted: 10/05/2018] [Indexed: 02/07/2023]
Abstract
Genotypic trade‐offs are fundamental to the understanding of the evolution of life‐history traits. In particular, the evolution of optimal host defense and the maintenance of variation in defense against infectious disease is thought to be underpinned by such evolutionary trade‐offs. However, empirical demonstrations of these trade‐offs that satisfy the strict assumptions made by theoretical models are rare. Additionally, none of these trade‐offs have yet been shown to be robustly replicable using a variety of different experimental approaches to rule out confounding issues with particular experimental designs. Here, we use inbred isolines as a novel experimental approach to test whether a trade‐off between viral resistance and growth rate in Plodia interpunctella, previously demonstrated by multiple selection experiments, is robust and meets the strict criteria required to underpin theoretical work in this field. Critically, we demonstrate that this trade‐off is both genetic and constitutive. This finding helps support the large body of theory that relies on these assumptions, and makes this trade‐off for resistance unique in being replicated through multiple experimental approaches and definitively shown to be genetic and constitutive.
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Affiliation(s)
- Lewis J Bartlett
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn, United Kingdom
| | - Lena Wilfert
- Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn, United Kingdom
| | - Michael Boots
- Department of Integrative Biology, University of California, Berkeley, California, 94720
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15
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Irvine MA, Bull JC, Keeling MJ. Disease transmission promotes evolution of host spatial patterns. J R Soc Interface 2017; 13:rsif.2016.0463. [PMID: 27628172 PMCID: PMC5046947 DOI: 10.1098/rsif.2016.0463] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 08/23/2016] [Indexed: 11/12/2022] Open
Abstract
Ecological dynamics can produce a variety of striking patterns. On ecological time scales, pattern formation has been hypothesized to be due to the interaction between a species and its local environment. On longer time scales, evolutionary factors must be taken into account. To examine the evolutionary robustness of spatial pattern formation, we construct a spatially explicit model of vegetation in the presence of a pathogen. Initially, we compare the dynamics for vegetation parameters that lead to competition induced spatial patterns and those that do not. Over ecological time scales, banded spatial patterns dramatically reduced the ability of the pathogen to spread, lowered its endemic density and hence increased the persistence of the vegetation. To gain an evolutionary understanding, each plant was given a heritable trait defining its resilience to competition; greater competition leads to lower vegetation density but stronger spatial patterns. When a disease is introduced, the selective pressure on the plant's resilience to the competition parameter is determined by the transmission of the disease. For high transmission, vegetation that has low resilience to competition and hence strong spatial patterning is an evolutionarily stable strategy. This demonstrates a novel mechanism by which striking spatial patterns can be maintained by disease-driven selection.
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Affiliation(s)
- Michael A Irvine
- Centre for Complexity Science, University of Warwick, Coventry, UK
| | - James C Bull
- Department of Biosciences, University of Swansea, Swansea, UK
| | - Matthew J Keeling
- Mathematics Institute and Department of Biological Sciences, University of Warwick, Coventry, UK
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16
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Ecological and evolutionary approaches to managing honeybee disease. Nat Ecol Evol 2017; 1:1250-1262. [PMID: 29046562 PMCID: PMC5749923 DOI: 10.1038/s41559-017-0246-z] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 06/20/2017] [Indexed: 12/12/2022]
Abstract
Honeybee declines are a serious threat to global agricultural security and productivity. Although multiple factors contribute to these declines, parasites are a key driver. Disease problems in honeybees have intensified in recent years, despite increasing attention to addressing them. Here we argue that we must focus on the principles of disease ecology and evolution to understand disease dynamics, assess the severity of disease threats, and control these threats via honeybee management. We cover the ecological context of honeybee disease, including both host and parasite factors driving current transmission dynamics, and then discuss evolutionary dynamics including how beekeeping management practices may drive selection for more virulent parasites. We then outline how ecological and evolutionary principles can guide disease mitigation in honeybees, including several practical management suggestions for addressing short- and long-term disease dynamics and consequences. Multiple interacting factors have contributed to the rapid decline of honeybee populations worldwide. Here, the authors review the impact of parasites and pathogens, and how ecological and evolutionary principles can guide management practices.
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17
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The impact of resource quality on the evolution of virulence in spatially heterogeneous environments. J Theor Biol 2017; 416:1-7. [DOI: 10.1016/j.jtbi.2016.12.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 12/03/2016] [Accepted: 12/21/2016] [Indexed: 02/02/2023]
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18
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Schmid-Hempel P. Parasites and Their Social Hosts. Trends Parasitol 2017; 33:453-462. [PMID: 28169113 DOI: 10.1016/j.pt.2017.01.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 01/04/2017] [Accepted: 01/05/2017] [Indexed: 11/16/2022]
Abstract
The study of parasitism in socially living organisms shows that social group size correlates with the risk of infection, but group structure - and thus differences in contact networks - is generally more important. Also, genetic makeup or environmental conditions have effects. 'Social immunity' focuses on defence against parasites that are particular to social living. Recently, the role of socially transmitted microbiota for defence has become a focus, too. But whether and how parasites adapt to social organisms - beyond adaptation to solitary hosts - is poorly understood. Genomic and proteomic methods, as well as network analysis, will be tools that hold promise for many unsolved questions, but to expand our concepts in the first place is a much needed agenda.
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Affiliation(s)
- Paul Schmid-Hempel
- ETH Zürich, Institute of Integrative Biology (IBZ), ETH-Zentrum CHN, Universitätsstrasse 16, CH-8092 Zürich, Switzerland.
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19
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Lion S. Moment equations in spatial evolutionary ecology. J Theor Biol 2016; 405:46-57. [DOI: 10.1016/j.jtbi.2015.10.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 10/06/2015] [Accepted: 10/08/2015] [Indexed: 11/28/2022]
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20
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Zhang J, Chen Z, Liu Z. Fostering cooperation of selfish agents through public goods in relation to the loners. Phys Rev E 2016; 93:032320. [PMID: 27078379 DOI: 10.1103/physreve.93.032320] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2015] [Indexed: 11/07/2022]
Abstract
Altruistic behaviors in multiplayer groups have obtained great attention in the context of the public goods game, which poses a riddle from the evolutionary viewpoint. Here we focus on a particular type of public goods game model in which the benefits of cooperation are either discounted or synergistically enhanced at the appearance of multiple cooperators in a group. Moreover, we focus on the three-strategies profile by adding the role of loners, besides the often-used cooperation and defection. Using the replicator dynamic equations, we investigate a range of dynamical portraits that characterizes the properties of the steady state. Analysis results indicate that loners and cooperators both have chances to be the stable equilibrium points in the presence of perturbations, while defectors fail to do so in this three-strategy competition. Moreover, the coexistence state, in which all three strategies exist in equilibrium, can be led by suitable parameters and stabilized for perturbations. These results elucidate the interplay between the characteristics of the public goods game and evolutionary dynamics in well-mixed systems.
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Affiliation(s)
- Jianlei Zhang
- Department of Automation, College of Computer and Control Engineering, Nankai University, Tianjin 300071, People's Republic of China and Tianjin Key Laboratory of Intelligent Robotics, Computer and Control Engineering, Nankai University, Tianjin 300071, People's Republic of China
| | - Zengqiang Chen
- Department of Automation, College of Computer and Control Engineering, Nankai University, Tianjin 300071, People's Republic of China and Tianjin Key Laboratory of Intelligent Robotics, Computer and Control Engineering, Nankai University, Tianjin 300071, People's Republic of China
| | - Zhongxin Liu
- Department of Automation, College of Computer and Control Engineering, Nankai University, Tianjin 300071, People's Republic of China and Tianjin Key Laboratory of Intelligent Robotics, Computer and Control Engineering, Nankai University, Tianjin 300071, People's Republic of China
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21
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Débarre F. Fitness costs in spatially structured environments. Evolution 2015; 69:1329-35. [DOI: 10.1111/evo.12646] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 03/12/2015] [Indexed: 10/23/2022]
Affiliation(s)
- Florence Débarre
- Department of Zoology and Biodiversity Research Centre; University of British Columbia; 6270 University Boulevard Vancouver BC V6T 1Z4 Canada
- Centre for Ecology & Conservation; University of Exeter; Penryn Campus Penryn TR10 9FE United Kingdom
- Current address : Center for Interdisciplinary Research in Biology, CNRS UMR 7241; Equipe Stochastic Models for the Inference of Life Evolution, Collège de France; 11 place Marcelin Berthelot 75231 Paris Cedex 5 France
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22
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Carlsson-Granér U, Thrall PH. Host resistance and pathogen infectivity in host populations with varying connectivity. Evolution 2015; 69:926-38. [DOI: 10.1111/evo.12631] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 02/18/2015] [Indexed: 01/28/2023]
Affiliation(s)
- Ulla Carlsson-Granér
- Department of Ecology and Environmental Sciences; University of Umeå; S-90187 Umeå Sweden
| | - Peter H. Thrall
- CSIRO Agriculture Flagship GPO Box 1600; Canberra ACT 2601 Australia
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23
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Ashby B, King KC. Diversity and the maintenance of sex by parasites. J Evol Biol 2015; 28:511-20. [PMID: 25676723 DOI: 10.1111/jeb.12590] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Accepted: 01/12/2015] [Indexed: 01/21/2023]
Abstract
The Red Queen hypothesis (RQH) predicts that parasite-mediated selection will maintain sexual individuals in the face of competition from asexual lineages. The prediction is that sexual individuals will be difficult targets for coevolving parasites if they give rise to more genetically diverse offspring than asexual lineages. However, increasing host genetic diversity is known to suppress parasite spread, which could provide a short-term advantage to clonal lineages and lead to the extinction of sex. We test these ideas using a stochastic individual-based model. We find that if parasites are readily transmissible, then sex is most likely to be maintained when host diversity is high, in agreement with the RQH. If transmission rates are lower, however, we find that sexual populations are most likely to persist for intermediate levels of diversity. Our findings thus highlight the importance of genetic diversity and its impact on epidemiological dynamics for the maintenance of sex by parasites.
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Affiliation(s)
- B Ashby
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Penryn, Cornwall, UK
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24
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Lion S, Gandon S. Evolution of spatially structured host-parasite interactions. J Evol Biol 2015; 28:10-28. [DOI: 10.1111/jeb.12551] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 11/06/2014] [Accepted: 11/10/2014] [Indexed: 01/19/2023]
Affiliation(s)
- S. Lion
- CEFE UMR 5175; CNRS - Université de Montpellier - Université Paul-Valéry Montpellier - EPHE; Montpellier Cedex 5 France
| | - S. Gandon
- CEFE UMR 5175; CNRS - Université de Montpellier - Université Paul-Valéry Montpellier - EPHE; Montpellier Cedex 5 France
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25
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Díaz-Muñoz SL, Koskella B. Bacteria-phage interactions in natural environments. ADVANCES IN APPLIED MICROBIOLOGY 2014; 89:135-83. [PMID: 25131402 DOI: 10.1016/b978-0-12-800259-9.00004-4] [Citation(s) in RCA: 107] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Phages are considered the most abundant and diverse biological entities on Earth and are notable not only for their sheer abundance, but also for their influence on bacterial hosts. In nature, bacteria-phage relationships are complex and have far-reaching consequences beyond particular pairwise interactions, influencing everything from bacterial virulence to eukaryotic fitness to the carbon cycle. In this review, we examine bacteria and phage distributions in nature first by highlighting biogeographic patterns and nonhost environmental influences on phage distribution, then by considering the ways in which phages and bacteria interact, emphasizing phage life cycles, bacterial responses to phage infection, and the complex patterns of phage host specificity. Finally, we discuss phage impacts on bacterial abundance, genetics, and physiology, and further aim to clarify distinctions between current theoretical models and point out areas in need of future research.
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Affiliation(s)
- Samuel L Díaz-Muñoz
- Department of Biology, Center for Genomics and Systems Biology, New York University, New York, New York, USA; Department of Integrative Biology, University of California, Berkeley, California, USA; Department of Plant and Microbial Biology, University of California, Berkeley, California, USA
| | - Britt Koskella
- Department of Biosciences, University of Exeter, Penryn Campus, Tremough, Cornwall, United Kingdom.
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26
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Pamminger T, Foitzik S, Metzler D, Pennings PS. Oh sister, where art thou? Spatial population structure and the evolution of an altruistic defence trait. J Evol Biol 2014; 27:2443-56. [PMID: 25262856 DOI: 10.1111/jeb.12496] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 08/28/2014] [Accepted: 08/29/2014] [Indexed: 11/29/2022]
Abstract
The evolution of parasite virulence and host defences is affected by population structure. This effect has been confirmed in studies focusing on large spatial scales, whereas the importance of local structure is not well understood. Slavemaking ants are social parasites that exploit workers of another species to rear their offspring. Enslaved workers of the host species Temnothorax longispinosus have been found to exhibit an effective post-enslavement defence behaviour: enslaved workers were observed killing a large proportion of the parasites' offspring. As enslaved workers do not reproduce, they gain no direct fitness benefit from this 'rebellion' behaviour. However, there may be an indirect benefit: neighbouring host nests that are related to 'rebel' nests can benefit from a reduced raiding pressure, as a result of the reduction in parasite nest size due to the enslaved workers' killing behaviour. We use a simple mathematical model to examine whether the small-scale population structure of the host species could explain the evolution of this potentially altruistic defence trait against slavemaking ants. We find that this is the case if enslaved host workers are related to nearby host nests. In a population genetic study, we confirm that enslaved workers are, indeed, more closely related to host nests within the raiding range of their resident slavemaker nest, than to host nests outside the raiding range. This small-scale population structure seems to be a result of polydomy (e.g. the occupation of several nests in close proximity by a single colony) and could have enabled the evolution of 'rebellion' by kin selection.
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Affiliation(s)
- T Pamminger
- Institute of Zoology, Johannes Gutenberg University of Mainz, Mainz, Germany; School of Life Sciences, University of Sussex, Brighton, UK
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27
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28
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Pierce AA, de Roode JC, Altizer S, Bartel RA. Extreme heterogeneity in parasitism despite low population genetic structure among monarch butterflies inhabiting the Hawaiian Islands. PLoS One 2014; 9:e100061. [PMID: 24926796 PMCID: PMC4057267 DOI: 10.1371/journal.pone.0100061] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Accepted: 05/22/2014] [Indexed: 11/18/2022] Open
Abstract
Host movement and spatial structure can strongly influence the ecology and evolution of infectious diseases, with limited host movement potentially leading to high spatial heterogeneity in infection. Monarch butterflies (Danaus plexippus) are best known for undertaking a spectacular long-distance migration in eastern North America; however, they also form non-migratory populations that breed year-round in milder climates such as Hawaii and other tropical locations. Prior work showed an inverse relationship between monarch migratory propensity and the prevalence of the protozoan parasite, Ophryocystis elektroscirrha. Here, we sampled monarchs from replicate sites within each of four Hawaiian Islands to ask whether these populations show consistently high prevalence of the protozoan parasite as seen for monarchs from several other non-migratory populations. Counter to our predictions, we observed striking spatial heterogeneity in parasite prevalence, with infection rates per site ranging from 4-85%. We next used microsatellite markers to ask whether the observed variation in infection might be explained by limited host movement and spatial sub-structuring among sites. Our results showed that monarchs across the Hawaiian Islands form one admixed population, supporting high gene flow among sites. Moreover, measures of individual-level genetic diversity did not predict host infection status, as might be expected if more inbred hosts harbored higher parasite loads. These results suggest that other factors such as landscape-level environmental variation or colonization-extinction processes might instead cause the extreme heterogeneity in monarch butterfly infection observed here.
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Affiliation(s)
- Amanda A. Pierce
- Biology Department, Emory University, Atlanta, Georgia, United States of America
- * E-mail:
| | - Jacobus C. de Roode
- Biology Department, Emory University, Atlanta, Georgia, United States of America
| | - Sonia Altizer
- Odum School of Ecology, University of Georgia, Athens, Georgia, United States of America
| | - Rebecca A. Bartel
- Odum School of Ecology, University of Georgia, Athens, Georgia, United States of America
- Red Wolf Recovery Program, United States Fish and Wildlife Service, Manteo, North Carolina, United States of America
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29
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Abstract
We introduce the field of Hamiltonian medicine, which centres on the roles of genetic relatedness in human health and disease. Hamiltonian medicine represents the application of basic social-evolution theory, for interactions involving kinship, to core issues in medicine such as pathogens, cancer, optimal growth and mental illness. It encompasses three domains, which involve conflict and cooperation between: (i) microbes or cancer cells, within humans, (ii) genes expressed in humans, (iii) human individuals. A set of six core principles, based on these domains and their interfaces, serves to conceptually organize the field, and contextualize illustrative examples. The primary usefulness of Hamiltonian medicine is that, like Darwinian medicine more generally, it provides novel insights into what data will be productive to collect, to address important clinical and public health problems. Our synthesis of this nascent field is intended predominantly for evolutionary and behavioural biologists who aspire to address questions directly relevant to human health and disease.
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Affiliation(s)
- Bernard Crespi
- Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, CanadaV5A 1S6
| | - Kevin Foster
- Department of Zoology, University of Oxford, Oxford OX1 3PS, UK
| | - Francisco Úbeda
- School of Biological Sciences, Royal Holloway University of London, Egham TW20 0EX, UK
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30
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Papaïx J, Burdon JJ, Lannou C, Thrall PH. Evolution of pathogen specialisation in a host metapopulation: joint effects of host and pathogen dispersal. PLoS Comput Biol 2014; 10:e1003633. [PMID: 24853675 PMCID: PMC4031062 DOI: 10.1371/journal.pcbi.1003633] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Accepted: 04/08/2014] [Indexed: 11/22/2022] Open
Abstract
Metapopulation processes are important determinants of epidemiological and evolutionary dynamics in host-pathogen systems, and are therefore central to explaining observed patterns of disease or genetic diversity. In particular, the spatial scale of interactions between pathogens and their hosts is of primary importance because migration rates of one species can affect both spatial and temporal heterogeneity of selection on the other. In this study we developed a stochastic and discrete time simulation model to specifically examine the joint effects of host and pathogen dispersal on the evolution of pathogen specialisation in a spatially explicit metapopulation. We consider a plant-pathogen system in which the host metapopulation is composed of two plant genotypes. The pathogen is dispersed by air-borne spores on the host metapopulation. The pathogen population is characterised by a single life-history trait under selection, the infection efficacy. We found that restricted host dispersal can lead to high amount of pathogen diversity and that the extent of pathogen specialisation varied according to the spatial scale of host-pathogen dispersal. We also discuss the role of population asynchrony in determining pathogen evolutionary outcomes.
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Affiliation(s)
- Julien Papaïx
- INRA, UMR 1290 BIOGER, Thiverval-Grignon, France
- INRA, UR 341 MIA, Jouy-en-Josas, France
- CSIRO Plant Industry, Canberra, Australia
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31
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Kurvers RHJM, Krause J, Croft DP, Wilson ADM, Wolf M. The evolutionary and ecological consequences of animal social networks: emerging issues. Trends Ecol Evol 2014; 29:326-35. [PMID: 24792356 DOI: 10.1016/j.tree.2014.04.002] [Citation(s) in RCA: 140] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 03/16/2014] [Accepted: 04/04/2014] [Indexed: 10/25/2022]
Abstract
The first generation of research on animal social networks was primarily aimed at introducing the concept of social networks to the fields of animal behaviour and behavioural ecology. More recently, a diverse body of evidence has shown that social fine structure matters on a broader scale than initially expected, affecting many key ecological and evolutionary processes. Here, we review this development. We discuss the effects of social network structure on evolutionary dynamics (genetic drift, fixation probabilities, and frequency-dependent selection) and social evolution (cooperation and between-individual behavioural differences). We discuss how social network structure can affect important coevolutionary processes (host-pathogen interactions and mutualisms) and population stability. We also discuss the potentially important, but poorly studied, role of social network structure on dispersal and invasion. Throughout, we highlight important areas for future research.
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Affiliation(s)
- Ralf H J M Kurvers
- Department of Biology and Ecology of Fishes, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Mueggelseedamm 310, 12587 Berlin, Germany.
| | - Jens Krause
- Department of Biology and Ecology of Fishes, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Mueggelseedamm 310, 12587 Berlin, Germany; Humboldt University of Berlin, Faculty of Life Sciences, Invalidenstraße 42, 10115 Berlin, Germany
| | - Darren P Croft
- Centre for Research In Animal Behaviour, College of Life & Environmental Science, University of Exeter, Exeter, EX4 4QG, UK
| | - Alexander D M Wilson
- Department of Biology and Ecology of Fishes, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Mueggelseedamm 310, 12587 Berlin, Germany
| | - Max Wolf
- Department of Biology and Ecology of Fishes, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Mueggelseedamm 310, 12587 Berlin, Germany
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32
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Abstract
Parasite virulence, or the damage a parasite does to its host, is measured in terms of both host costs (reductions in host growth, reproduction and survival) and parasite benefits (increased transmission and parasite numbers) in the literature. Much work has shown that ecological and genetic factors can be strong selective forces in virulence evolution. This review uses kin selection theory to explore how variations in host ecological parameters impact the genetic relatedness of parasite populations and thus virulence. We provide a broad overview of virulence and population genetics studies and then draw connections to existing knowledge about natural parasite populations. The impact of host movement (transporting parasites) and host resistance (filtering parasites) on the genetic structure and virulence of parasite populations is explored, and empirical studies of these factors using Plasmodium and trematode systems are proposed.
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33
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Abou-El-Naga IF. Meta-analysis indicates lack of local adaptation of Schistosoma mansoni to Biomphalaria alexandrina in Egypt. Parasitol Res 2014; 113:1185-94. [DOI: 10.1007/s00436-014-3756-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 01/03/2014] [Indexed: 01/09/2023]
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Ashby B, Gupta S, Buckling A. Spatial structure mitigates fitness costs in host-parasite coevolution. Am Nat 2014; 183:E64-74. [PMID: 24561607 DOI: 10.1086/674826] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The extent of population mixing is known to influence the coevolutionary outcomes of many host and parasite traits, including the evolution of generalism (the ability to resist or infect a broad range of genotypes). While the segregation of populations into interconnected demes has been shown to influence the evolution of generalism, the role of local interactions between individuals is unclear. Here, we combine an individual-based model of microbial communities with a well-established framework of genetic specificity that matches empirical observations of bacterium-phage interactions. We find the evolution of generalism in well-mixed populations to be highly sensitive to the severity of associated fitness costs, but the constraining effect of costs on the evolution of generalism is lessened in spatially structured populations. The contrasting outcomes between the two environments can be explained by different scales of competition (i.e., global vs. local). These findings suggest that local interactions may have important effects on the evolution of generalism in host-parasite interactions, particularly in the presence of high fitness costs.
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Affiliation(s)
- Ben Ashby
- Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, United Kingdom
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35
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Knowles SCL, Wood MJ, Alves R, Sheldon BC. Dispersal in a patchy landscape reveals contrasting determinants of infection in a wild avian malaria system. J Anim Ecol 2013; 83:429-39. [DOI: 10.1111/1365-2656.12154] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2013] [Accepted: 09/14/2013] [Indexed: 11/30/2022]
Affiliation(s)
- Sarah C. L. Knowles
- Department of Zoology; Edward Grey Institute; University of Oxford; South Parks Road Oxford OX1 3PS UK
- Department of Infectious Disease Epidemiology; Imperial College London; St Mary's Campus, Norfolk Place London W2 1PG UK
| | - Matthew J. Wood
- Department of Zoology; Edward Grey Institute; University of Oxford; South Parks Road Oxford OX1 3PS UK
- Department of Natural and Social Sciences; University of Gloucestershire; Francis Close Hall Cheltenham GL50 4AZ UK
| | - Ricardo Alves
- Department of Zoology; Edward Grey Institute; University of Oxford; South Parks Road Oxford OX1 3PS UK
| | - Ben C. Sheldon
- Department of Zoology; Edward Grey Institute; University of Oxford; South Parks Road Oxford OX1 3PS UK
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36
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Tack AJM, Horns F, Laine AL. The impact of spatial scale and habitat configuration on patterns of trait variation and local adaptation in a wild plant parasite. Evolution 2013; 68:176-89. [PMID: 24372603 PMCID: PMC3916884 DOI: 10.1111/evo.12239] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Accepted: 07/26/2013] [Indexed: 11/29/2022]
Abstract
Theory indicates that spatial scale and habitat configuration are fundamental for coevolutionary dynamics and how diversity is maintained in host-pathogen interactions. Yet, we lack empirical data to translate the theory to natural host-parasite systems. In this study, we conduct a multiscale cross-inoculation study using the specialist wild plant pathogen Podosphaera plantaginis on its host plant Plantago lanceolata. We apply the same sampling scheme to a region with highly fragmented (Åland) and continuous (Saaremaa) host populations. Although theory predicts higher parasite virulence in continuous regions, we did not detect differences in traits conferring virulence among the regions. Patterns of adaptation were highly scale dependent. We detected parasite maladaptation among regions, and among populations separated by intermediate distances (6.0-40.0 km) within the fragmented region. In contrast, parasite performance did not vary significantly according to host origin in the continuous landscape. For both regions, differentiation among populations was much larger for genetic variation than for phenotypic variation, indicating balancing selection maintaining phenotypic variation within populations. Our findings illustrate the critical role of spatial scale and habitat configuration in driving host-parasite coevolution. The absence of more aggressive strains in the continuous landscape, in contrast to theoretical predictions, has major implications for long-term decision making in conservation, agriculture, and public health.
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Affiliation(s)
- Ayco J M Tack
- Metapopulation Research Group, Department of Biosciences, University of Helsinki, PO Box 65 (Viikinkaari 1), University of Helsinki, FI-00014, Finland.
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37
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Affiliation(s)
- R. Thornhill
- Department of Biology The University of New Mexico Albuquerque NM USA
| | - C. L. Fincher
- Institute of Neuroscience and Psychology University of Glasgow Glasgow UK
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38
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Mancy R, Prosser P, Rogers S. Discrete and continuous time simulations of spatial ecological processes predict different final population sizes and interspecific competition outcomes. Ecol Modell 2013. [DOI: 10.1016/j.ecolmodel.2013.03.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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39
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Donnelly R, Best A, White A, Boots M. Seasonality selects for more acutely virulent parasites when virulence is density dependent. Proc Biol Sci 2013. [PMID: 23193133 DOI: 10.1098/rspb.2012.2464] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Host condition is often likely to influence parasite virulence. Furthermore, condition may often be correlated with host density, and therefore, it is important to understand the role of density-dependent virulence (DDV). We examine the consequences of DDV to the evolution of parasites in both seasonal and non-seasonal environments. In particular, we consider seasonality in host birth rate that results in a fluctuating host density and therefore a variable virulence. We show that parasites are selected for lower exploitation, and therefore lower transmission and virulence as the strength of DDV increases without seasonality. This is an important insight from our models; DDV has the opposite effect on the evolution of parasites to that of higher baseline mortality. Our key result is that although seasonality does not affect the evolution of virulence in classical models, with DDV parasites in seasonal environments are predicted to evolve to be more acute. This suggests that in more seasonal environments wildlife disease is likely to be more rather than less virulent if DDV is widespread.
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Affiliation(s)
- R Donnelly
- Department of Mathematics, Maxwell Institute for Mathematical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, UK.
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Molina-Morales M, Gabriel Martínez J, Martín-Gálvez D, A Dawson D, Rodríguez-Ruiz J, Burke T, Avilés JM. Evidence of long-term structured cuckoo parasitism on individual magpie hosts. J Anim Ecol 2012; 82:389-98. [PMID: 23237197 DOI: 10.1111/1365-2656.12022] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Accepted: 10/08/2012] [Indexed: 12/01/2022]
Abstract
Brood parasites usually reduce their host's breeding success, resulting in strong selection for the evolution of host defences. Intriguingly, some host individuals/populations show no defence against parasitism, which has been explained within the frame of three different evolutionary hypotheses. One of these hypotheses posits that intermediate levels of defence at the population level may result from nonrandom distribution of parasitism among host individuals (i.e. structured parasitism). Empirical evidence for structured brood parasitism is, however, lacking for hosts of European cuckoos due to the absence of long-term studies. Here, we seek to identify the patterns of structured parasitism by studying great spotted cuckoo parasitism on individual magpie hosts over five breeding seasons. We also aim to identify whether individual characteristics of female magpies and/or their territories were related to the status of repeated parasitism. We found that 28·3% of the females in our population consistently escaped from cuckoo parasitism. Only 11·3% of females were always parasitized, and the remaining 60·4% changed their parasitism status. The percentage of females that maintained their status of parasitism (i.e. either parasitized or nonparasitized) between consecutive years varied over the study. Females that never suffered cuckoo parasitism built bigger nests than parasitized females at the beginning of the breeding season and smaller nests than those of parasitized females later in the season. Nonparasitized females also moved little from year to year and preferred areas with different characteristics over the course of the breeding season than parasitized females. Overall, females escaping from cuckoo parasitism reared twice as many chicks per year than those that were parasitized. In conclusion, our study reveals for first time the existence of a structured pattern of cuckoo parasitism based on phenotypic characteristics of individual hosts and of their territories.
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Affiliation(s)
- Mercedes Molina-Morales
- Departamento de Zoología, Universidad de Granada, Granada, E-18071, Spain; Department of Animal and Plant Sciences, University of Sheffield, Sheffield, S10 2TN, UK
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Horns F, Hood ME. The evolution of disease resistance and tolerance in spatially structured populations. Ecol Evol 2012; 2:1705-11. [PMID: 22957174 PMCID: PMC3434923 DOI: 10.1002/ece3.290] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2012] [Revised: 05/07/2012] [Accepted: 05/08/2012] [Indexed: 11/07/2022] Open
Abstract
THE UBIQUITOUS CHALLENGE FROM INFECTIOUS DISEASE HAS PROMPTED THE EVOLUTION OF DIVERSE HOST DEFENSES, WHICH CAN BE DIVIDED INTO TWO BROAD CLASSES: resistance (which limits pathogen growth and infection) and tolerance (which does not limit infection, but instead reduces or offsets its negative fitness consequences). Resistance and tolerance may provide equivalent short-term benefits, but have fundamentally different epidemiological consequences and thus exhibit different evolutionary behaviors. We consider the evolution of resistance and tolerance in a spatially structured population using a stochastic simulation model. We show that tolerance can invade a population of susceptible individuals (i.e., neither resistant nor tolerant) with higher cost than resistance, even though they each provide equivalent direct benefits to the host, because tolerant hosts impose higher disease burden upon vulnerable competitors. However, in spatially structured settings, tolerance can invade a population of resistant hosts only with lower cost than resistance due to spatial genetic structure and the higher local incidence of disease around invading tolerant individuals. The evolution of tolerance is therefore constrained by spatial genetic structure in a manner not previously revealed by nonspatially explicit models, suggesting mechanisms that could maintain variation or limit the occurrence of tolerance relative to resistance.
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Affiliation(s)
- Felix Horns
- Department of Biology, Amherst College Amherst, Massachusetts 01002
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Messinger SM, Ostling A. The influence of host demography, pathogen virulence, and relationships with pathogen virulence on the evolution of pathogen transmission in a spatial context. Evol Ecol 2012. [DOI: 10.1007/s10682-012-9594-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Débarre F, Lion S, van Baalen M, Gandon S. Evolution of host life-history traits in a spatially structured host-parasite system. Am Nat 2011; 179:52-63. [PMID: 22173460 DOI: 10.1086/663199] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Most models for the evolution of host defense against parasites assume that host populations are not spatially structured. Yet local interactions and limited dispersal can strongly affect the evolutionary outcome, because they significantly alter epidemiological feedbacks and the spatial genetic structuring of the host and pathogen populations. We provide a general framework to study the evolution of a number of host life-history traits in a spatially structured host population infected by a horizontally transmitted parasite. Our analysis teases apart the selective pressures on hosts and helps disentangle the direct fitness effect of mutations and their indirect effects via the influence of spatial structure on the genetic, demographic, and epidemiological structure of the host population. We then illustrate the evolutionary consequences of spatial structure by focusing on the evolution of two host defense strategies against parasitism: suicide upon infection and reduced transmission. Because they bring no direct fitness benefit, these strategies are counterselected or selectively neutral in a nonspatial setting, but we show that they can be selected for in a spatially structured environment. Our study thus sheds light on the evolution of altruistic defense mechanisms that have been observed in various biological systems.
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Affiliation(s)
- F Débarre
- Centre d'Écologie Fonctionnelle et Évolutive, Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR) 5175, F-34293 Montpellier Cedex 5, France.
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