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Owings CG, Banerjee A, Picard CJ. Temporal population genetic structure of Phormia regina (Diptera: Calliphoridae). JOURNAL OF MEDICAL ENTOMOLOGY 2023:tjad115. [PMID: 37862592 DOI: 10.1093/jme/tjad115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 07/23/2023] [Accepted: 08/15/2023] [Indexed: 10/22/2023]
Abstract
The genetic structure of forensically important blow fly (Brauer & Bergenstamm) (Diptera: Calliphoridae) populations has remained elusive despite high relatedness within wild-caught samples. This research aimed to determine if the implementation of a high-resolution spatiotemporal sampling design would reveal latent genetic structure among blow fly populations and to elucidate any environmental impacts on observed patterns of genetic structure. Adult females of the black blow fly, Phormia regina (Meigen) (Diptera: Calliphoridae), were collected from 9 urban parks in Indiana, USA over 3 yr and genotyped at 6 polymorphic microsatellite loci. The data analysis involved 3 clustering methods: principal coordinate analysis (PCoA), discriminant analysis of principal components (DAPC), and STRUCTURE. While the PCoA did not uncover any discernible clustering patterns, the DAPC and STRUCTURE analyses yielded significant results, with 9 and 4 genetic clusters, respectively. Visualization of the STRUCTURE bar plot revealed N = 11 temporal demarcations indicating barriers to gene flow. An analysis of molecular variance of these STRUCTURE-inferred populations supported strong temporally driven genetic differentiation (FST = 0.048, F'ST = 0.664) relative to geographic differentiation (FST = 0.009, F'ST = 0.241). Integrated Nested Laplace Approximation and Boosted Regression Tree analyses revealed that collection timepoint and 4 main abiotic factors (temperature, humidity, precipitation, and wind speed) were associated with the genetic subdivisions observed for P. regina. A complex interplay between environmental conditions, the unique reproductive strategies of the blow fly, and the extensive dispersal abilities of these organisms likely drives the strong genetic structure of P. regina in the Midwestern US.
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Affiliation(s)
- Charity G Owings
- Department of Entomology and Plant Pathology, University of Tennessee, 2505 E. J. Chapman Dr., Knoxville, TN 37996, USA
- Department of Biology, Indiana University-Purdue University Indianapolis, 723 W Michigan Street, SL 306, Indianapolis, IN 46202, USA
| | - Aniruddha Banerjee
- Department of Geography, Indiana University-Purdue University Indianapolis, 425 University Boulevard, Cavanaugh Hall 441, Indianapolis, IN 46202, USA
| | - Christine J Picard
- Department of Biology, Indiana University-Purdue University Indianapolis, 723 W Michigan Street, SL 306, Indianapolis, IN 46202, USA
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2
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Minard G, Kahilainen A, Biere A, Pakkanen H, Mappes J, Saastamoinen M. Complex plant quality-microbiota-population interactions modulate the response of a specialist herbivore to the defence of its host plant. Funct Ecol 2022; 36:2873-2888. [PMID: 36632135 PMCID: PMC9826300 DOI: 10.1111/1365-2435.14177] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 08/26/2022] [Indexed: 01/14/2023]
Abstract
Many specialist herbivores have evolved strategies to cope with plant defences, with gut microbiota potentially participating to such adaptations.In this study, we assessed whether the history of plant use (population origin) and microbiota may interact with plant defence adaptation.We tested whether microbiota enhance the performance of Melitaea cinxia larvae on their host plant, Plantago lanceolata and increase their ability to cope the defensive compounds, iridoid glycosides (IGs).The gut microbiota were significantly affected by both larval population origin and host plant IG level. Contrary to our prediction, impoverishing the microbiota with antibiotic treatment did not reduce larval performance.As expected for this specialized insect herbivore, sequestration of one of IGs was higher in larvae fed with plants producing higher concentration of IGs. These larvae also showed metabolic signature of intoxication (i.e. decrease in Lysine levels). However, intoxication on highly defended plants was only observed when larvae with a history of poorly defended plants were simultaneously treated with antibiotics.Our results suggest that both adaptation and microbiota contribute to the metabolic response of herbivores to plant defence though complex interactions. Read the free Plain Language Summary for this article on the Journal blog.
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Affiliation(s)
- Guillaume Minard
- Organismal and Evolutionary Biology Research ProgrammeUniversity of HelsinkiHelsinkiFinland,Université de LyonLyonFrance,Ecologie MicrobienneUMR CNRS 5557, UMR INRA 1418, VetAgro Sup, Université Lyon 1VilleurbanneFrance
| | - Aapo Kahilainen
- Organismal and Evolutionary Biology Research ProgrammeUniversity of HelsinkiHelsinkiFinland,Finnish Environment InstituteBiodiversity CentreHelsinkiFinland
| | - Arjen Biere
- Department of Terrestrial EcologyNetherlands Institute of Ecology (NIOO‐KNAW)WageningenThe Netherlands
| | - Hannu Pakkanen
- Department of ChemistryUniversity of JyväskyläJyväskyläFinland
| | - Johanna Mappes
- Organismal and Evolutionary Biology Research ProgrammeUniversity of HelsinkiHelsinkiFinland,Department of Biological and Environmental ScienceUniversity of JyväskyläJyväskyläFinland
| | - Marjo Saastamoinen
- Organismal and Evolutionary Biology Research ProgrammeUniversity of HelsinkiHelsinkiFinland,Helsinki Institute of Life SciencesUniversity of HelsinkiHelsinkiFinland
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3
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Abstract
Hyperparasitoids are some of the most diverse members of insect food webs. True hyperparasitoids parasitize the larvae of other parasitoids, reaching these larvae with their ovipositor through the herbivore that hosts the parasitoid larva. During pupation, primary parasitoids also may be attacked by pseudohyperparasitoids that lay their eggs on the parasitoid (pre)pupae. By attacking primary parasitoids, hyperparasitoids may affect herbivore population dynamics, and they have been identified as a major challenge in biological control. Over the past decades, research, especially on aphid- and caterpillar-associated hyperparasitoids, has revealed that hyperparasitoids challenge rules on nutrient use efficiency in trophic chains, account for herbivore outbreaks, or stabilize competitive interactions in lower trophic levels, and they may use cues derived from complex interaction networks to locate their hosts. This review focuses on the fascinating ecology of hyperparasitoids related to how they exploit and locate their often inconspicuous hosts and the insect community processes in which hyperparasitoids are prominent players.
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Affiliation(s)
- Erik H Poelman
- Laboratory of Entomology, Wageningen University and Research, 6700 AA Wageningen, The Netherlands;
| | - Antonino Cusumano
- Department of Agricultural, Food and Forest Sciences, University of Palermo, 90128 Palermo, Italy;
| | - Jetske G de Boer
- Terrestrial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), 6708 PB Wageningen, The Netherlands;
- Aeres University of Applied Sciences, 6708 PB Wageningen, The Netherlands
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4
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Duplouy A, Nair A, Nyman T, van Nouhuys S. Long-term spatiotemporal genetic structure of an accidental parasitoid introduction, and local changes in prevalence of its associated Wolbachia symbiont. Mol Ecol 2021; 30:4368-4380. [PMID: 34233062 DOI: 10.1111/mec.16065] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 06/14/2021] [Accepted: 07/02/2021] [Indexed: 11/30/2022]
Abstract
Population bottlenecks associated with founder events strongly impact the establishment and genetic makeup of populations. In addition to their genotype, founding individuals also bring along parasites, as well as symbionts that can manipulate the phenotype of their host, affecting the host population establishment, dynamics and evolution. Thus, to understand introduction, invasion, and spread, we should identify the roles played by accompanying symbionts. In 1991, the parasitoid wasp, Hyposoter horticola, and its associated hyperparasitoid were accidentally introduced from the main Åland islands, Finland, to an isolated island in the archipelago, along with their host, the Glanville fritillary butterfly. Though the receiving island was unoccupied, the butterfly was present on some of the small islands in the vicinity. The three introduced species have persisted locally ever since. A strain of the endosymbiotic bacterium Wolbachia has an intermediate prevalence in the parasitoid H. horticola across the main Åland population. The infection increases its susceptibility of to hyperparasitism. We investigated the establishment and spread of the parasitoid, along with patterns of prevalence of its symbiont using 323 specimens collected between 1992 and 2013, from five localities across Åland, including the source and introduced populations. Using 14 microsatellites and one mitochondrial marker, we suggest that the relatively diverse founding population and occasional migration between islands might have facilitated the persistence of all isolated populations, despite multiple local population crashes. We also show that where the hyperparasitoid is absent, and thus selection against infected wasp genotypes is relaxed, there is near-fixation of Wolbachia.
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Affiliation(s)
- Anne Duplouy
- Department of Biology, Lund University, Lund, Sweden.,Organismal and Evolutionary Biology Research Program, The University of Helsinki, Helsinki, Finland
| | - Abhilash Nair
- Organismal and Evolutionary Biology Research Program, The University of Helsinki, Helsinki, Finland
| | - Toshka Nyman
- Organismal and Evolutionary Biology Research Program, The University of Helsinki, Helsinki, Finland
| | - Saskya van Nouhuys
- Organismal and Evolutionary Biology Research Program, The University of Helsinki, Helsinki, Finland.,Department of Ecology and Evolutionary Biology, Ithaca, New York, USA
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5
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Nonaka E, Kaitala V. The effects of functional response and host abundance fluctuations on genetic rescue in parasitoids with single-locus sex determination. Ecol Evol 2020; 10:13030-13043. [PMID: 33304514 PMCID: PMC7713968 DOI: 10.1002/ece3.6889] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 08/20/2020] [Indexed: 11/29/2022] Open
Abstract
Many parasitoids have single-locus complementary sex determination (sl-CSD), which produces sterile or inviable males when homozygous at the sex determining locus. A previous study theoretically showed that small populations have elevated risks of extinction due to the positive feedback between inbreeding and small population size, referred to as the diploid male vortex. A few modeling studies have suggested that the diploid male vortex may not be as common because balancing selection at sex determining loci tends to maintain high allelic diversity in spatially structured populations. However, the generality of the conclusion is yet uncertain, as they were drawn either from models developed for particular systems or from a general-purpose competition model. To attest the conclusion, we study several well-studied host-parasitoid models that incorporate functional response specifying the number of attacked hosts given a host density and derive the conditions for a diploid male vortex in a single population. Then, we develop spatially structured individual-based versions of the models to include female behavior, diploid male fertility, and temporal fluctuations. The results show that producing a handful of successful offspring per female parasitoid could enable parasitoid persistence when a typical number of CSD alleles are present. The effect of functional response depends on the levels of fluctuations in host abundance, and inviable or partially fertile diploid males and a small increase in dispersal can alleviate the risk of a diploid male vortex. Our work supports the generality of effective genetic rescue in spatially connected parasitoid populations with sl-CSD. However, under more variable climate, the efficacy of the CSD mechanism may substantially decline.
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Affiliation(s)
- Etsuko Nonaka
- Department of Ecology, Environment, and Plant ScienceStockholm UniversityStockholmSweden
- Present address:
Department of Biological and Environmental ScienceUniversity of JyväskyläJyväskyläFinland
| | - Veijo Kaitala
- Organismal and Evolutionary Biology ProgrammeUniversity of HelsinkiHelsinkiFinland
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6
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Opedal ØH, Ovaskainen O, Saastamoinen M, Laine AL, van Nouhuys S. Host-plant availability drives the spatiotemporal dynamics of interacting metapopulations across a fragmented landscape. Ecology 2020; 101:e03186. [PMID: 32892363 PMCID: PMC7757193 DOI: 10.1002/ecy.3186] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 07/01/2020] [Accepted: 07/20/2020] [Indexed: 11/26/2022]
Abstract
The dynamics of ecological communities depend partly on species interactions within and among trophic levels. Experimental work has demonstrated the impact of species interactions on the species involved, but it remains unclear whether these effects can also be detected in long‐term time series across heterogeneous landscapes. We analyzed a 19‐yr time series of patch occupancy by the Glanville fritillary butterfly Melitaea cinxia, its specialist parasitoid wasp Cotesia melitaearum, and the specialist fungal pathogen Podosphaera plantaginis infecting Plantago lanceolata, a host plant of the Glanville fritillary. These species share a network of more than 4,000 habitat patches in the Åland islands, providing a metacommunity data set of unique spatial and temporal resolution. To assess the influence of interactions among the butterfly, parasitoid, and mildew on metacommunity dynamics, we modeled local colonization and extinction rates of each species while including or excluding the presence of potentially interacting species in the previous year as predictors. The metapopulation dynamics of all focal species varied both along a gradient in host plant abundance, and spatially as indicated by strong effects of local connectivity. Colonization and to a lesser extent extinction rates depended also on the presence of interacting species within patches. However, the directions of most effects differed from expectations based on previous experimental and modeling work, and the inferred influence of species interactions on observed metacommunity dynamics was limited. These results suggest that although local interactions among the butterfly, parasitoid, and mildew occur, their roles in metacommunity spatiotemporal dynamics are relatively weak. Instead, all species respond to variation in plant abundance, which may in turn fluctuate in response to variation in climate, land use, or other environmental factors.
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Affiliation(s)
- Øystein H Opedal
- Organismal and Evolutionary Biology Research Programme, University of Helsinki, Helsinki, Finland.,Department of Biology, Lund University, Lund, SE-223 62, Sweden
| | - Otso Ovaskainen
- Organismal and Evolutionary Biology Research Programme, University of Helsinki, Helsinki, Finland.,Centre for Biodiversity Dynamics, Department of Biology, Norwegian University of Science and Technology, Trondheim, N-7491, Norway
| | - Marjo Saastamoinen
- Organismal and Evolutionary Biology Research Programme, University of Helsinki, Helsinki, Finland.,Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Anna-Liisa Laine
- Organismal and Evolutionary Biology Research Programme, University of Helsinki, Helsinki, Finland.,Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, CH-8057, Switzerland
| | - Saskya van Nouhuys
- Organismal and Evolutionary Biology Research Programme, University of Helsinki, Helsinki, Finland.,Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, New York, 14853, USA
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7
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Duplouy A, Minard G, Saastamoinen M. The gut bacterial community affects immunity but not metabolism in a specialist herbivorous butterfly. Ecol Evol 2020; 10:8755-8769. [PMID: 32884655 PMCID: PMC7452788 DOI: 10.1002/ece3.6573] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 06/11/2020] [Accepted: 06/15/2020] [Indexed: 12/20/2022] Open
Abstract
Plant tissues often lack essential nutritive elements and may contain a range of secondary toxic compounds. As nutritional imbalance in food intake may affect the performances of herbivores, the latter have evolved a variety of physiological mechanisms to cope with the challenges of digesting their plant-based diet. Some of these strategies involve living in association with symbiotic microbes that promote the digestion and detoxification of plant compounds or supply their host with essential nutrients missing from the plant diet. In Lepidoptera, a growing body of evidence has, however, recently challenged the idea that herbivores are nutritionally dependent on their gut microbial community. It is suggested that many of the herbivorous Lepidopteran species may not host a resident microbial community, but rather a transient one, acquired from their environment and diet. Studies directly testing these hypotheses are however scarce and come from an even more limited number of species.By coupling comparative metabarcoding, immune gene expression, and metabolomics analyses with experimental manipulation of the gut microbial community of prediapause larvae of the Glanville fritillary butterfly (Melitaea cinxia, L.), we tested whether the gut microbial community supports early larval growth and survival, or modulates metabolism or immunity during early stages of development.We successfully altered this microbiota through antibiotic treatments and consecutively restored it through fecal transplants from conspecifics. Our study suggests that although the microbiota is involved in the up-regulation of an antimicrobial peptide, it did not affect the life history traits or the metabolism of early instars larvae.This study confirms the poor impact of the microbiota on diverse life history traits of yet another Lepidoptera species. However, it also suggests that potential eco-evolutionary host-symbiont strategies that take place in the gut of herbivorous butterfly hosts might have been disregarded, particularly how the microbiota may affect the host immune system homeostasis.
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Affiliation(s)
- Anne Duplouy
- Department of Biology, Biodiversity UnitLund UniversityLundSweden
- Research Centre for Ecological changes, Organismal and Evolutionary Biology Research ProgramFaculty of Environmental and Biological SciencesUniversity of HelsinkiHelsinkiFinland
| | - Guillaume Minard
- Research Centre for Ecological changes, Organismal and Evolutionary Biology Research ProgramFaculty of Environmental and Biological SciencesUniversity of HelsinkiHelsinkiFinland
- Laboratory of Microbial EcologyUMR CNRS 5557UMR INRA 1418University Claude Bernard Lyon 1VilleurbanneFrance
| | - Marjo Saastamoinen
- Research Centre for Ecological changes, Organismal and Evolutionary Biology Research ProgramFaculty of Environmental and Biological SciencesUniversity of HelsinkiHelsinkiFinland
- Helsinki Institute of Life ScienceUniversity of HelsinkiHelsinkiFinland
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8
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Minard G, Tikhonov G, Ovaskainen O, Saastamoinen M. The microbiome of the Melitaea cinxia butterfly shows marked variation but is only little explained by the traits of the butterfly or its host plant. Environ Microbiol 2019; 21:4253-4269. [PMID: 31436012 PMCID: PMC6900084 DOI: 10.1111/1462-2920.14786] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 08/14/2019] [Accepted: 08/20/2019] [Indexed: 12/13/2022]
Abstract
Understanding of the ecological factors that shape intraspecific variation of insect microbiota in natural populations is relatively poor. In Lepidopteran caterpillars, microbiota is assumed to be mainly composed of transient bacterial symbionts acquired from the host plant. We sampled Glanville fritillary (Melitaea cinxia) caterpillars from natural populations to describe their gut microbiome and to identify potential ecological factors that determine its structure. Our results demonstrate high variability of microbiota composition even among caterpillars that shared the same host plant individual and most likely the same genetic background. We observed that the caterpillars harboured microbial classes that varied among individuals and alternated between two distinct communities (one composed of mainly Enterobacteriaceae and another with more variable microbiota community). Even though the general structure of the microbiota was not attributed to the measured ecological factors, we found that phylogenetically similar microbiota showed corresponding responses to the sex and the parasitoid infection of the caterpillar and to those of the host plant's microbial and chemical composition. Our results indicate high among-individual variability in the microbiota of the M. cinxia caterpillar and contradict previous findings that the host plant is the major driver of the microbiota communities of insect herbivores.
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Affiliation(s)
- Guillaume Minard
- Organismal and Evolutionary Biology Research ProgrammeUniversity of HelsinkiHelsinkiFinland
- Université de LyonLyonFrance
- Ecologie Microbienne, UMR CNRS 5557, UMR INRA 1418, VetAgro Sup, Université Lyon 1VilleurbanneFrance
| | - Gleb Tikhonov
- Organismal and Evolutionary Biology Research ProgrammeUniversity of HelsinkiHelsinkiFinland
| | - Otso Ovaskainen
- Organismal and Evolutionary Biology Research ProgrammeUniversity of HelsinkiHelsinkiFinland
- Centre for Biodiversity Dynamics, Department of BiologyNorwegian University of Science and TechnologyN‐7491TrondheimNorway
| | - Marjo Saastamoinen
- Organismal and Evolutionary Biology Research ProgrammeUniversity of HelsinkiHelsinkiFinland
- Helsinki Institute of Life SciencesUniversity of HelsinkiHelsinkiFinland
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9
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10
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DiLeo MF, Husby A, Saastamoinen M. Landscape permeability and individual variation in a dispersal-linked gene jointly determine genetic structure in the Glanville fritillary butterfly. Evol Lett 2018; 2:544-556. [PMID: 30564438 PMCID: PMC6292703 DOI: 10.1002/evl3.90] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 10/22/2018] [Accepted: 10/29/2018] [Indexed: 12/14/2022] Open
Abstract
There is now clear evidence that species across a broad range of taxa harbor extensive heritable variation in dispersal. While studies suggest that this variation can facilitate demographic outcomes such as range expansion and invasions, few have considered the consequences of intraspecific variation in dispersal for the maintenance and distribution of genetic variation across fragmented landscapes. Here, we examine how landscape characteristics and individual variation in dispersal combine to predict genetic structure using genomic and spatial data from the Glanville fritillary butterfly. We used linear and latent factor mixed models to identify the landscape features that best predict spatial sorting of alleles in the dispersal-related gene phosphoglucose isomerase (Pgi). We next used structural equation modeling to test if variation in Pgi mediated gene flow as measured by Fst at putatively neutral loci. In a year when the population was recovering following a large decline, individuals with a genotype associated with greater dispersal ability were found at significantly higher frequencies in populations isolated by water and forest, and these populations showed lower levels of genetic differentiation at neutral loci. These relationships disappeared in the next year when metapopulation density was high, suggesting that the effects of individual variation are context dependent. Together our results highlight that (1) more complex aspects of landscape structure beyond just the configuration of habitat can be important for maintaining spatial variation in dispersal traits and (2) that individual variation in dispersal plays a key role in maintaining genetic variation across fragmented landscapes.
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Affiliation(s)
- Michelle F. DiLeo
- Organismal and Evolutionary Biology Research ProgrammeUniversity of HelsinkiPO Box 6500014Finland
| | - Arild Husby
- Organismal and Evolutionary Biology Research ProgrammeUniversity of HelsinkiPO Box 6500014Finland
- Department of Evolutionary Biology, EBCUppsala UniversityNorbyvägen 18D75236UppsalaSweden
| | - Marjo Saastamoinen
- Organismal and Evolutionary Biology Research ProgrammeUniversity of HelsinkiPO Box 6500014Finland
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11
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Ovaskainen O, Saastamoinen M. Frontiers in Metapopulation Biology: The Legacy of Ilkka Hanski. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2018. [DOI: 10.1146/annurev-ecolsys-110617-062519] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This review of metapopulation biology has a special focus on Professor Ilkka Hanski's (1953–2016) research. Hanski made seminal contributions to both empirical and theoretical metapopulation biology throughout his scientific career. Hanski's early research focused on ecological aspects of metapopulation biology, in particular how the spatial structure of a landscape influences extinction thresholds and how habitat loss and fragmentation can result in extinction debt. Hanski then used the Glanville fritillary system as a natural laboratory within which he studied genetic and evolutionary processes, such as the influence of inbreeding on extinction risk and variation in selection for dispersal traits generated by landscape variation. During the last years of his career, Hanski's work was in the forefront of the rapidly developing field of eco-evolutionary dynamics. Hanski was a pioneer in showing how molecular-level underpinnings of trait variation can explain why evolutionary change can occur rapidly in natural populations and how these changes can subsequently influence ecological dynamics.
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Affiliation(s)
- Otso Ovaskainen
- Organismal and Evolutionary Biology Research Programme, University of Helsinki, FI-00014 Helsinki, Finland;,
- Centre for Biodiversity Dynamics, Department of Biology, Norwegian University of Science and Technology, N-7491 Trondheim, Norway
| | - Marjo Saastamoinen
- Organismal and Evolutionary Biology Research Programme, University of Helsinki, FI-00014 Helsinki, Finland;,
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12
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Nair A, Nonaka E, van Nouhuys S. Increased fluctuation in a butterfly metapopulation leads to diploid males and decline of a hyperparasitoid. Proc Biol Sci 2018; 285:rspb.2018.0372. [PMID: 30135149 PMCID: PMC6125898 DOI: 10.1098/rspb.2018.0372] [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: 04/21/2018] [Accepted: 07/20/2018] [Indexed: 12/14/2022] Open
Abstract
Climate change can increase spatial synchrony of population dynamics, leading to large-scale fluctuation that destabilizes communities. High trophic level species such as parasitoids are disproportionally affected because they depend on unstable resources. Most parasitoid wasps have complementary sex determination, producing sterile males when inbred, which can theoretically lead to population extinction via the diploid male vortex (DMV). We examined this process empirically using a hyperparasitoid population inhabiting a spatially structured host population in a large fragmented landscape. Over four years of high host butterfly metapopulation fluctuation, diploid male production by the wasp increased, and effective population size declined precipitously. Our multitrophic spatially structured model shows that host population fluctuation can cause local extinctions of the hyperparasitoid because of the DMV. However, regionally it persists because spatial structure allows for efficient local genetic rescue via balancing selection for rare alleles carried by immigrants. This is, to our knowledge, the first empirically based study of the possibility of the DMV in a natural host–parasitoid system.
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Affiliation(s)
- Abhilash Nair
- Metapopulation Research Centre, Department of Biosciences, University of Helsinki, PO Box 65, 00014 Helsinki, Finland
| | - Etsuko Nonaka
- Metapopulation Research Centre, Department of Biosciences, University of Helsinki, PO Box 65, 00014 Helsinki, Finland.,Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm, 114 18, Sweden
| | - Saskya van Nouhuys
- Metapopulation Research Centre, Department of Biosciences, University of Helsinki, PO Box 65, 00014 Helsinki, Finland .,Department of Entomology, Cornell University, Ithaca, NY 14853, USA
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13
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Fountain T, Husby A, Nonaka E, DiLeo MF, Korhonen JH, Rastas P, Schulz T, Saastamoinen M, Hanski I. Inferring dispersal across a fragmented landscape using reconstructed families in the Glanville fritillary butterfly. Evol Appl 2017. [DOI: 10.1111/eva.12552] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Affiliation(s)
- Toby Fountain
- Department of Biosciences; University of Helsinki; Helsinki Finland
- Evolutionary Biology Centre; Uppsala University; Uppsala Sweden
| | - Arild Husby
- Department of Biosciences; University of Helsinki; Helsinki Finland
| | - Etsuko Nonaka
- Department of Biosciences; University of Helsinki; Helsinki Finland
- Department of Biology; Lund University; Lund Sweden
| | | | - Janne H. Korhonen
- Department of Biosciences; University of Helsinki; Helsinki Finland
- Department of Computer Science; Aalto University; Aalto Finland
| | - Pasi Rastas
- Department of Biosciences; University of Helsinki; Helsinki Finland
- Department of Zoology; University of Cambridge; Cambridge UK
| | - Torsti Schulz
- Department of Biosciences; University of Helsinki; Helsinki Finland
| | | | - Ilkka Hanski
- Department of Biosciences; University of Helsinki; Helsinki Finland
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14
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Wei SJ, Zhou Y, Fan XL, Hoffmann AA, Cao LJ, Chen XX, Xu ZF. Different genetic structures revealed resident populations of a specialist parasitoid wasp in contrast to its migratory host. Ecol Evol 2017; 7:5400-5409. [PMID: 28770077 PMCID: PMC5528221 DOI: 10.1002/ece3.3097] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 04/21/2017] [Accepted: 05/02/2017] [Indexed: 11/08/2022] Open
Abstract
Genetic comparisons of parasitoids and their hosts are expected to reflect ecological and evolutionary processes that influence the interactions between species. The parasitoid wasp, Cotesia vestalis, and its host diamondback moth (DBM), Plutella xylostella, provide opportunities to test whether the specialist natural enemy migrates seasonally with its host or occurs as resident population. We genotyped 17 microsatellite loci and two mitochondrial genes for 158 female adults of C. vestalis collected from 12 geographical populations, as well as nine microsatellite loci for 127 DBM larvae from six separate sites. The samplings covered both the likely source (southern) and immigrant (northern) areas of DBM from China. Populations of C. vestalis fell into three groups, pointing to isolation in northwestern and southwestern China and strong genetic differentiation of these populations from others in central and eastern China. In contrast, DBM showed much weaker genetic differentiation and high rates of gene flow. TESS analysis identified the immigrant populations of DBM as showing admixture in northern China. Genetic disconnect between C. vestalis and its host suggests that the parasitoid did not migrate yearly with its host but likely consisted of resident populations in places where its host could not survive in winter.
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Affiliation(s)
- Shu-Jun Wei
- Institute of Plant and Environmental Protection Beijing Academy of Agriculture and Forestry Sciences Beijing China
| | - Yuan Zhou
- Institute of Plant and Environmental Protection Beijing Academy of Agriculture and Forestry Sciences Beijing China.,College of Agriculture South China Agricultural University Guangzhou China
| | - Xu-Lei Fan
- Institute of Plant and Environmental Protection Beijing Academy of Agriculture and Forestry Sciences Beijing China
| | - Ary A Hoffmann
- School of BioSciences Bio21 Institute The University of Melbourne Parkville VIC Australia
| | - Li-Jun Cao
- Institute of Plant and Environmental Protection Beijing Academy of Agriculture and Forestry Sciences Beijing China
| | - Xue-Xin Chen
- Institute of Insect Sciences Zhejiang University Hangzhou China
| | - Zai-Fu Xu
- College of Agriculture South China Agricultural University Guangzhou China
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15
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Parratt SR, Barrès B, Penczykowski RM, Laine AL. Local adaptation at higher trophic levels: contrasting hyperparasite-pathogen infection dynamics in the field and laboratory. Mol Ecol 2017; 26:1964-1979. [PMID: 27859910 PMCID: PMC5412677 DOI: 10.1111/mec.13928] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 10/25/2016] [Accepted: 11/01/2016] [Indexed: 12/23/2022]
Abstract
Predicting and controlling infectious disease epidemics is a major challenge facing the management of agriculture, human and wildlife health. Co-evolutionarily derived patterns of local adaptation among pathogen populations have the potential to generate variation in disease epidemiology; however, studies of local adaptation in disease systems have mostly focused on interactions between competing pathogens or pathogens and their hosts. In nature, parasites and pathogens are also subject to attack by hyperparasitic natural enemies that can severely impact upon their infection dynamics. However, few studies have investigated whether this interaction varies across combinations of pathogen-hyperparasite strains, and whether this influences hyperparasite incidence in natural pathogen populations. Here, we test whether the association between a hyperparasitic fungus, Ampelomyces, and a single powdery mildew host, Podosphaera plantaginis, varies among genotype combinations, and whether this drives hyperparasite incidence in nature. Laboratory inoculation studies reveal that genotype, genotype × genotype interactions and local adaptation affect hyperparasite infection. However, observations of a natural pathogen metapopulation reveal that spatial rather than genetic factors predict the risk of hyperparasite presence. Our results highlight how sensitive the outcome of biocontrol using hyperparasites is to selection of hyperparasite strains.
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Affiliation(s)
- Steven R Parratt
- Metapopulation Research Centre, Department of Biosciences, University of Helsinki, Viikinkaari 1, 00014, Helsinki, Finland
| | - Benoit Barrès
- Metapopulation Research Centre, Department of Biosciences, University of Helsinki, Viikinkaari 1, 00014, Helsinki, Finland
| | - Rachel M Penczykowski
- Metapopulation Research Centre, Department of Biosciences, University of Helsinki, Viikinkaari 1, 00014, Helsinki, Finland
| | - Anna-Liisa Laine
- Metapopulation Research Centre, Department of Biosciences, University of Helsinki, Viikinkaari 1, 00014, Helsinki, Finland
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16
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Nieminen M, Nouhuys SV. The Roles of Trophic Interactions, Competition and Landscape in Determining Metacommunity Structure of a Seed-Feeding Weevil and Its Parasitoids. ANN ZOOL FENN 2017. [DOI: 10.5735/086.054.0109] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Marko Nieminen
- Department of Biosciences, P.O. Box 65, FI-00014 University of Helsinki, Finland
- Centre for Biodiversity Genomics, Biodiversity Institute of Ontario, University of Guelph, Guelph, ON, N1G 2W1, Canada
| | - Saskya van Nouhuys
- Department of Biosciences, P.O. Box 65, FI-00014 University of Helsinki, Finland
- Department of Entomology, Cornell University, Ithaca, NY 14850, USA
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17
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van Nouhuys S, Kohonen M, Duplouy A. Wolbachia increases the susceptibility of a parasitoid wasp to hyperparasitism. J Exp Biol 2016; 219:2984-2990. [DOI: 10.1242/jeb.140699] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 07/18/2016] [Indexed: 01/24/2023]
Abstract
ABSTRACT
The success of maternally transmitted endosymbiotic bacteria, such as Wolbachia, is directly linked to their host reproduction but in direct conflict with other parasites that kill the host before it reaches reproductive maturity. Therefore, symbionts that have evolved strategies to increase their host’s ability to evade lethal parasites may have high penetrance, while detrimental symbionts would be selected against, leading to lower penetrance or extinction from the host population. In a natural population of the parasitoid wasp Hyposoter horticola in the Åland Islands (Finland), the Wolbachia strain wHho persists at an intermediate prevalence (∼50%). Additionally, there is a negative correlation between the prevalence of Wolbachia and a hyperparasitoid wasp, Mesochorus cf. stigmaticus, in the landscape. Using a manipulative field experiment, we addressed the persistence of Wolbachia at this intermediate level, and tested whether the observed negative correlation could be due to Wolbachia inducing either susceptibility or resistance to parasitism. We show that infection with Wolbachia does not influence the ability of the wasp to parasitize its butterfly host, Melitaea cinxia, but that hyperparasitism of the wasp increases in the presence of wHho. Consequently, the symbiont is detrimental, and in order to persist in the host population, must also have a positive effect on fitness that outweighs the costly burden of susceptibility to widespread parasitism.
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Affiliation(s)
- Saskya van Nouhuys
- University of Helsinki, Metapopulation Research Centre, Department of Biosciences, PL 65, Viikinkaari 1, Helsinki FI-00014, Finland
| | - Minna Kohonen
- University of Helsinki, Metapopulation Research Centre, Department of Biosciences, PL 65, Viikinkaari 1, Helsinki FI-00014, Finland
| | - Anne Duplouy
- University of Helsinki, Metapopulation Research Centre, Department of Biosciences, PL 65, Viikinkaari 1, Helsinki FI-00014, Finland
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