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Madden JR, Buckley R, Ratcliffe S. Large-scale correlations between gamebird release and management and animal biodiversity metrics in lowland Great Britain. Ecol Evol 2023; 13:e10059. [PMID: 37168985 PMCID: PMC10166649 DOI: 10.1002/ece3.10059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 03/15/2023] [Accepted: 04/14/2023] [Indexed: 05/13/2023] Open
Abstract
The ecological effects on populations of non-game species driven by the annual release and management of tens of millions of gamebirds for recreational shooting are complex and relatively poorly understood. We investigated these effects at a national scale, considering multiple taxa simultaneously. We used records from the UK National Biodiversity Network Atlas to compare animal species and diversity metrics previously suggested to be affected by behaviors of the released birds, or because resources or habitats are influenced by game management or both processes. We contrasted records from 1 km grid squares where gamebirds were reported released in Great Britain, and control squares with similar land cover but where no releases were reported. There were more records overall reported from release grid squares (RGS) compared with controls (CGS), perhaps due to greater reporting effort or greater biological richness. We found fewer foxes in RGS and fewest in grid squares with largest releases, but more carrion crows in RGS. We found no consistent effects for buzzards, ravens, jays, or magpies. There were more rodents and gray squirrels reported from RGS but no differences for reptiles. There were more butterflies but fewer beetles reported from RGS but no consistent patterns for Orthoptera or ground beetles considered common gamebird prey. Farmland and woodland birds exhibited higher abundance, richness, and diversity in RGS when considering absolute records, but woodland bird abundance and richness were lower when correcting for the relative number of records. These nationwide results, despite crude data resolution, reveal diverse effects of gamebird release and management at a national scale and across trophic levels, increasing some non-game animal populations while decreasing others. This should alert practitioners, opponents, and legislators that a focus on single taxa effects, either positive or negative, may obscure the simultaneous changes in other taxa.
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Affiliation(s)
- Joah Robert Madden
- Psychology, Centre for Research in Animal BehaviourUniversity of ExeterExeterUK
| | - Rosie Buckley
- Psychology, Centre for Research in Animal BehaviourUniversity of ExeterExeterUK
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2
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Wu Y, Brown A, Ricklefs RE. Host-specific soil microbes contribute to habitat restriction of closely related oaks ( Quercus spp.). Ecol Evol 2022; 12:e9614. [PMID: 36523531 PMCID: PMC9745265 DOI: 10.1002/ece3.9614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 11/15/2022] [Accepted: 11/18/2022] [Indexed: 12/15/2022] Open
Abstract
Habitat divergence among close relatives is a common phenomenon. Studying the mechanisms behind habitat divergence is fundamental to understanding niche partitioning, species diversification, and other evolutionary processes. Recent studies found that soil microbes regulate the abundance and diversity of plant species. However, it remains unclear whether soil microbes can affect the habitat distributions of plants and drive habitat divergence. To fill in this knowledge gap, we investigated whether soil microbes might restrict habitat distributions of closely related oaks (Quercus spp.) in eastern North America. We performed a soil inoculum experiment using two pairs of sister species (i.e., the most closely related species) that show habitat divergence: Quercus alba (local species) vs. Q. michauxii (foreign), and Q. shumardii (local) vs. Q. acerifolia (foreign). To test whether host-specific soil microbes are responsible for habitat restriction, we investigated the impact of local sister live soil (containing soil microbes associated with local sister species) on the survival and growth of local and foreign species. Second, to test whether habitat-specific soil microbes are responsible for habitat restriction, we examined the effect of local habitat live soil (containing soil microbes within local sister's habitats, but not directly associated with local sister species) on the seedlings of local and foreign species. We found that local sister live soil decreased the survival and biomass of foreign species' seedlings while increasing those of local species, suggesting that host-specific soil microbes could potentially mediate habitat exclusion. In contrast, local habitat live soil did not differentially affect the survival or biomass of the local vs. foreign species. Our study indicates that soil microbes associated with one sister species can suppress the recruitment of the other host species, contributing to the habitat partitioning of close relatives. Considering the complex interactions with soil microbes is essential for understanding the habitat distributions of closely related plants.
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Affiliation(s)
- Yingtong Wu
- Department of BiologyUniversity of Missouri–St. LouisSt. LouisMissouriUSA
- Whitney R. Harris World Ecology CenterUniversity of Missouri–St. LouisSt. LouisMissouriUSA
| | - Alicia Brown
- Department of BiologyUniversity of Missouri–St. LouisSt. LouisMissouriUSA
- Whitney R. Harris World Ecology CenterUniversity of Missouri–St. LouisSt. LouisMissouriUSA
| | - Robert E. Ricklefs
- Department of BiologyUniversity of Missouri–St. LouisSt. LouisMissouriUSA
- Whitney R. Harris World Ecology CenterUniversity of Missouri–St. LouisSt. LouisMissouriUSA
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Sarabeev V, Balbuena JA, Desdevises Y, Morand S. Host-parasite relationships in invasive species: macroecological framework. Biol Invasions 2022. [DOI: 10.1007/s10530-022-02821-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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4
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Rząd I, Stapf A, Kornaś SA, Dzika E, Sałamatin R, Kaczmarek A, Kowal J, Wajdzik M, Zalewski K. Intestinal Helminth Communities of Grey Partridge Perdix perdix and Common Pheasant Phasianus colchicus in Poland. Animals (Basel) 2021; 11:ani11123396. [PMID: 34944174 PMCID: PMC8698192 DOI: 10.3390/ani11123396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/08/2021] [Accepted: 11/23/2021] [Indexed: 11/16/2022] Open
Abstract
Simple Summary The presence of intestinal parasites such as nematodes, cestodes, and trematodes is a serious problem for programmes for the conservation of partridges and pheasants, mainly involving the breeding of these birds and their release into the natural environment. These parasites can cause disease in these birds, whether farmed or free-living. The aim of this study was to describe the morphology of parasitic worms in the partridge, native to Poland, and the introduced pheasant, and to determine the level of infection of these birds with intestinal parasitic worms. The study showed that partridges are infected with several helminth species that had not previously been recorded in this species in Poland. Pheasants are more often infected by intestinal nematodes than are partridges. These worms can negatively affect the condition of partridges and increase their risk of infection with pathogenic protozoa. The results of parasitological examination should be used to develop programmes for diagnosis and monitoring of parasitic infections in order to keep flocks free of parasites. Abstract The aim of this study was to describe the morphology and means of identification of helminths in native partridges (65) and introduced pheasants (32) in Poland and to determine the level of intestinal infection of these birds by helminths using parasitological and ecological indices. The birds were acquired during the hunting season in the years 2015–2017. Nematodes, Capillaria phasianina, cestodes, Railietina friedbergeri, and one trematode, Brachylaima sp. were recorded for the first time in partridges in Poland. Our findings indicate that parasites are more prevalent in pheasants (prevalence 70.4%) than in partridges (prevalence 50.0%). The component community and infracommunity of parasites of partridges are more diverse (Simpson’s diversity index: 0.63 and mean Brillouin diversity index: 0.10 ± 0.17) and less dominated by a single parasite species (Capillaria sp., Berger-Parker dominance index: 0.53) than the pheasant parasite community (Simpson’s diversity index: 0.07, mean Brillouin diversity index: 0.005 ± 0.02, dominant species Heterakis gallinarum, Berger-Parker dominance index: 0.96). There were statistically significant differences between partridges and pheasants in the Brillouin diversity index and in the prevalence of Heterakis gallinarum (55.6% in pheasants vs. 19.0 in partridges). There were significant differences between wild and farmed partridges in the prevalence of infection by Capillaria sp. (4.3% vs. 37.5%) and H. gallinarum (39.1 vs. 6.2%). In conclusion, the pheasant was shown to be a reservoir, carrier, and shedder of nematodes, which may increase the risk of infection in partridges.
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Affiliation(s)
- Izabella Rząd
- Institute of Marine and Environmental Sciences, University of Szczecin, ul. Wąska 13, 71-415 Szczecin, Poland
- Molecular Biology and Biotechnology Centre, University of Szczecin, ul. Wąska 13, 71-415 Szczecin, Poland
- Correspondence:
| | - Agata Stapf
- Department of Biological Sciences, Faculty of Sport Science in Gorzów Wielkopolski, Poznan University of Physical Education, ul. Estkowskiego 13, 66-400 Gorzów Wielkopolski, Poland;
| | - Sławomir Adam Kornaś
- Department of Zoology and Animal Welfare, Faculty of Animal Science, University of Agriculture, Al. Mickiewicza 24/28, 31-059 Kraków, Poland; (S.A.K.); (J.K.)
| | - Ewa Dzika
- Department of Medical Biology, Collegium Medicum, University of Warmia and Mazury in Olsztyn, ul. Żołnierska 14 c, 10-561 Olsztyn, Poland;
| | - Rusłan Sałamatin
- Department of General Biology and Parasitology, Medical University of Warsaw, ul. Chałubińskiego 5, 02-004 Warsaw, Poland;
- Faculty of Medicine, Collegium Medicum, Cardinal Stefan Wyszynski University in Warsaw, ul. Kazimierza Wóycickiego 1/3, 01-938 Warsaw, Poland;
| | - Adam Kaczmarek
- Faculty of Medicine, Collegium Medicum, Cardinal Stefan Wyszynski University in Warsaw, ul. Kazimierza Wóycickiego 1/3, 01-938 Warsaw, Poland;
| | - Jerzy Kowal
- Department of Zoology and Animal Welfare, Faculty of Animal Science, University of Agriculture, Al. Mickiewicza 24/28, 31-059 Kraków, Poland; (S.A.K.); (J.K.)
| | - Marek Wajdzik
- Department of Forest Biodiversity, Faculty of Forestry, University of Agriculture, Al. 29-Listopada 46, 31-425 Kraków, Poland;
| | - Kazimierz Zalewski
- Department of Biochemistry, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, ul. Oczapowskiego 1a, 10-719 Olsztyn, Poland;
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Abbott KC, Eppinga MB, Umbanhowar J, Baudena M, Bever JD. Microbiome influence on host community dynamics: Conceptual integration of microbiome feedback with classical host-microbe theory. Ecol Lett 2021; 24:2796-2811. [PMID: 34608730 PMCID: PMC9292004 DOI: 10.1111/ele.13891] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 07/28/2021] [Accepted: 08/31/2021] [Indexed: 01/11/2023]
Abstract
Microbiomes have profound effects on host fitness, yet we struggle to understand the implications for host ecology. Microbiome influence on host ecology has been investigated using two independent frameworks. Classical ecological theory powerfully represents mechanistic interactions predicting environmental dependence of microbiome effects on host ecology, but these models are notoriously difficult to evaluate empirically. Alternatively, host-microbiome feedback theory represents impacts of microbiome dynamics on host fitness as simple net effects that are easily amenable to experimental evaluation. The feedback framework enabled rapid progress in understanding microbiomes' impacts on plant ecology, and can also be applied to animal hosts. We conceptually integrate these two frameworks by deriving expressions for net feedback in terms of mechanistic model parameters. This generates a precise mapping between net feedback theory and classic population modelling, thereby merging mechanistic understanding with experimental tractability, a necessary step for building a predictive understanding of microbiome influence on host ecology.
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Affiliation(s)
| | - Maarten B Eppinga
- University of Zurich, Zurich, Switzerland.,Copernicus Institute of Sustainable Development, Utrecht University, Utrecht, The Netherlands
| | | | - Mara Baudena
- Copernicus Institute of Sustainable Development, Utrecht University, Utrecht, The Netherlands.,National Research Council of Italy, Institute of Atmospheric Sciences, and Climate (CNR-ISAC), Torino, Italy
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Romeo C, Piscitelli AP, Santicchia F, Martinoli A, Ferrari N, Wauters LA. Invading parasites: spillover of an alien nematode reduces survival in a native species. Biol Invasions 2021. [DOI: 10.1007/s10530-021-02611-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
AbstractIt is widely assumed that spillover of alien parasites to native host species severely impacts naïve populations, ultimately conferring a competitive advantage to invading hosts that introduced them. Despite such host-switching events occurring in biological invasions, studies demonstrating the impact of alien macroparasites on native animal hosts are surprisingly few. In Europe, native red squirrels (Sciurus vulgaris) are replaced by introduced North American grey squirrels (S. carolinensis) mainly through resource competition, and, only in the United Kingdom and Ireland, by competition mediated by a viral disease. In Italy such disease is absent, but spillover of an introduced North American nematode (Strongyloides robustus) from grey to red squirrels is known to occur. Here, we used long-term (9 years) capture-mark-recapture and parasitological data of red squirrels in areas co-inhabited by grey squirrels in Northern Italy to investigate the impact of this alien helminth on naïve native squirrels’ body mass, local survival, and reproduction of females. We found no negative effect of the alien parasite on body mass or reproductive success, but intensity of infection by S. robustus reduced survival of both male and female squirrels. Significantly, survival of squirrels co-infected by their native nematode, Trypanoxyuris sciuri, was less affected by S. robustus, suggesting a protective effect of the native helminth against the new infection. Hence, we demonstrate that alien S. robustus spillover adds to the detrimental effects of resource competition and stress induced by grey squirrels, further reducing the fitness of the native species in the presence of the invasive competitor.
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Contribution of non-native galliforms to annual variation in biomass of British birds. Biol Invasions 2021. [DOI: 10.1007/s10530-021-02458-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
AbstractMillions of individuals of two species of non-native galliform birds, the Common Pheasant (Phasianus colchicus) and Red-legged Partridge (Alectoris rufa) are released into the British countryside annually in late summer, supplementing established breeding populations of these two species. The biomass of birds involved in these releases has been compared to the British breeding bird biomass. However, the validity of this comparison is compromised because the biomass of wild birds varies across the year due to reproduction, mortality and migration. How the biomass of Common Pheasants and Red-legged Partridges compares to that of other British bird species in late summer, or across the whole year, is currently unknown. Here, we produce estimates of how British bird biomass varies across the year, to assess the contribution of the two non-native galliforms to this variation. We show that overall British bird biomass is probably lowest around the start of the breeding season in April, and peaks in late summer and autumn. We estimate that around a quarter of British bird biomass annually is contributed by Common Pheasants and Red-legged Partridges, and that at their peak in August these two species represent about half of all wild bird biomass in Britain.
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Sage RB, Hoodless AN, Woodburn MIA, Draycott RAH, Madden JR, Sotherton NW. Summary review and synthesis: effects on habitats and wildlife of the release and management of pheasants and red-legged partridges on UK lowland shoots. WILDLIFE BIOLOGY 2020. [DOI: 10.2981/wlb.00766] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Rufus B. Sage
- R. B. Sage , A. N. Hoodless, M. I. A. Woodburn, R. A. H. Draycott, N. W. Sotherton, Game & Wildlife Conservation Trust, Fordingbridge, SP6 1EF, UK
| | - Andrew N. Hoodless
- R. B. Sage , A. N. Hoodless, M. I. A. Woodburn, R. A. H. Draycott, N. W. Sotherton, Game & Wildlife Conservation Trust, Fordingbridge, SP6 1EF, UK
| | - Maureen I. A. Woodburn
- R. B. Sage , A. N. Hoodless, M. I. A. Woodburn, R. A. H. Draycott, N. W. Sotherton, Game & Wildlife Conservation Trust, Fordingbridge, SP6 1EF, UK
| | - Roger A. H. Draycott
- R. B. Sage , A. N. Hoodless, M. I. A. Woodburn, R. A. H. Draycott, N. W. Sotherton, Game & Wildlife Conservation Trust, Fordingbridge, SP6 1EF, UK
| | - Joah R. Madden
- J. R. Madden, Center for Research in Animal Behaviour, Exeter Univ.,, Exeter, UK
| | - Nicolas W. Sotherton
- R. B. Sage , A. N. Hoodless, M. I. A. Woodburn, R. A. H. Draycott, N. W. Sotherton, Game & Wildlife Conservation Trust, Fordingbridge, SP6 1EF, UK
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Rinaud T, Harmange C, Pays O, Sarasa M, Saillard M, Bretagnolle V. Interspecific competition between two partridges in farmland landscapes. Anim Behav 2020. [DOI: 10.1016/j.anbehav.2020.04.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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First Report of Co-invasion by the Reptile Nematode Ozolaimus megatyphlon (Nematoda: Pharyngodonidae) with Invasive Green Iguanas (Iguana iguana) in the Asia-Pacific. Acta Parasitol 2020; 65:264-270. [PMID: 31748867 DOI: 10.2478/s11686-019-00144-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 11/07/2019] [Indexed: 11/20/2022]
Abstract
PURPOSE Co-invasion of naïve ecosystems by non-native parasites is a serious threat to global biodiversity, though such events are difficult to detect early in the invasion process. Green iguanas (Iguana iguana) are an emerging invasive species and have colonised several countries in the Asia-Pacific. A survey was undertaken to determine whether parasites of the green iguana had co-invaded naïve ecosystems with their introduced host. METHODS Over a 10-month period, wild green iguanas were trapped and euthanised in Singapore. All animals were necropsied and sampled for parasites. Parasites were then identified morphologically and subsequently characterised molecularly at the cytochrome c oxidase I (COI) locus. RESULTS The reptile nematode Ozolaimus megatyphlon was found in 38% of the sampled green iguanas, with burdens of 100 + worms in all infected animals. This represents the first recorded co-invasion of this species with wild green iguanas in the Asia-Pacific. Based on the molecular characterisation of the cytochrome c oxidase I (COI) locus, the first DNA barcode is provided for O. megatyphlon. CONCLUSION For the first time, the reptile nematode Ozolaimus megatyphlon is shown to be invasive and to have colonised the Asia-Pacific region with its introduced host, the green iguana. The DNA barcode provided here will facilitate future monitoring programmes as O. megatyphlon invades new habitats and countries.
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Edworthy AB, Langmore NE, Heinsohn R. Native fly parasites are the principal cause of nestling mortality in endangered Tasmanian pardalotes. Anim Conserv 2018. [DOI: 10.1111/acv.12444] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- A. B. Edworthy
- Research School of Biology Australian National University Canberra ACT Australia
| | - N. E. Langmore
- Research School of Biology Australian National University Canberra ACT Australia
| | - R. Heinsohn
- Fenner School of Environment and Society Australian National University Canberra ACT Australia
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12
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Blackburn TM, Gaston KJ. Abundance, biomass and energy use of native and alien breeding birds in Britain. Biol Invasions 2018. [DOI: 10.1007/s10530-018-1795-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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13
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Pheasant release in Great Britain: long-term and large-scale changes in the survival of a managed bird. EUR J WILDLIFE RES 2017. [DOI: 10.1007/s10344-017-1157-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Martin-Albarracin VL, Amico GC, Simberloff D, Nuñez MA. Impact of Non-Native Birds on Native Ecosystems: A Global Analysis. PLoS One 2015; 10:e0143070. [PMID: 26576053 PMCID: PMC4648570 DOI: 10.1371/journal.pone.0143070] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 10/30/2015] [Indexed: 11/24/2022] Open
Abstract
Introduction and naturalization of non-native species is one of the most important threats to global biodiversity. Birds have been widely introduced worldwide, but their impacts on populations, communities, and ecosystems have not received as much attention as those of other groups. This work is a global synthesis of the impact of nonnative birds on native ecosystems to determine (1) what groups, impacts, and locations have been best studied; (2) which taxonomic groups and which impacts have greatest effects on ecosystems, (3) how important are bird impacts at the community and ecosystem levels, and (4) what are the known benefits of nonnative birds to natural ecosystems. We conducted an extensive literature search that yielded 148 articles covering 39 species belonging to 18 families -18% of all known naturalized species. Studies were classified according to where they were conducted: Africa, Asia, Australasia, Europe, North America, South America, Islands of the Indian, of the Pacific, and of the Atlantic Ocean. Seven types of impact on native ecosystems were evaluated: competition, disease transmission, chemical, physical, or structural impact on ecosystem, grazing/ herbivory/ browsing, hybridization, predation, and interaction with other non-native species. Hybridization and disease transmission were the most important impacts, affecting the population and community levels. Ecosystem-level impacts, such as structural and chemical impacts were detected. Seven species were found to have positive impacts aside from negative ones. We provide suggestions for future studies focused on mechanisms of impact, regions, and understudied taxonomic groups.
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Affiliation(s)
- Valeria L. Martin-Albarracin
- Laboratorio Ecotono, INIBIOMA, CONICET-Universidad Nacional del Comahue, Bariloche, Río Negro, Argentina
- * E-mail:
| | - Guillermo C. Amico
- Laboratorio Ecotono, INIBIOMA, CONICET-Universidad Nacional del Comahue, Bariloche, Río Negro, Argentina
| | - Daniel Simberloff
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, Tennessee, United States of America
| | - Martin A. Nuñez
- Grupo de Ecología de Invasiones, INIBIOMA, CONICET-Universidad Nacional del Comahue, Bariloche, Río Negro, Argentina
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Commensal pathogens as a source of a coexistence mechanism. J Theor Biol 2015; 370:45-52. [DOI: 10.1016/j.jtbi.2015.01.030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 01/19/2015] [Accepted: 01/25/2015] [Indexed: 11/17/2022]
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Dunn AM, Hatcher MJ. Parasites and biological invasions: parallels, interactions, and control. Trends Parasitol 2015; 31:189-99. [PMID: 25613560 DOI: 10.1016/j.pt.2014.12.003] [Citation(s) in RCA: 126] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Revised: 12/05/2014] [Accepted: 12/11/2014] [Indexed: 10/24/2022]
Abstract
Species distributions are changing at an unprecedented rate owing to human activity. We examine how two key processes of redistribution - biological invasion and disease emergence - are interlinked. There are many parallels between invasion and emergence processes, and invasions can drive the spread of new diseases to wildlife. We examine the potential impacts of invasion and disease emergence, and discuss how these threats can be countered, focusing on biosecurity. In contrast with international policy on emerging diseases of humans and managed species, policy on invasive species and parasites of wildlife is fragmented, and the lack of international cooperation encourages individual parties to minimize their input into control. We call for international policy that acknowledges the strong links between emerging diseases and invasion risk.
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Affiliation(s)
- Alison M Dunn
- School of Biology, University of Leeds, Leeds LS2 9JT, UK.
| | - Melanie J Hatcher
- School of Biology, University of Leeds, Leeds LS2 9JT, UK; School of Biological Sciences, University of Bristol, Bristol BS8 1TH, UK
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Pagán I, Montes N, Milgroom MG, García-Arenal F. Vertical transmission selects for reduced virulence in a plant virus and for increased resistance in the host. PLoS Pathog 2014; 10:e1004293. [PMID: 25077948 PMCID: PMC4117603 DOI: 10.1371/journal.ppat.1004293] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 06/20/2014] [Indexed: 12/17/2022] Open
Abstract
For the last three decades, evolutionary biologists have sought to understand which factors modulate the evolution of parasite virulence. Although theory has identified several of these modulators, their effect has seldom been analysed experimentally. We investigated the role of two such major factors—the mode of transmission, and host adaptation in response to parasite evolution—in the evolution of virulence of the plant virus Cucumber mosaic virus (CMV) in its natural host Arabidopsis thaliana. To do so, we serially passaged three CMV strains under strict vertical and strict horizontal transmission, alternating both modes of transmission. We quantified seed (vertical) transmission rate, virus accumulation, effect on plant growth and virulence of evolved and non-evolved viruses in the original plants and in plants derived after five passages of vertical transmission. Our results indicated that vertical passaging led to adaptation of the virus to greater vertical transmission, which was associated with reductions of virus accumulation and virulence. On the other hand, horizontal serial passages did not significantly modify virus accumulation and virulence. The observed increases in CMV seed transmission, and reductions in virus accumulation and virulence in vertically passaged viruses were due also to reciprocal host adaptation during vertical passages, which additionally reduced virulence and multiplication of vertically passaged viruses. This result is consistent with plant-virus co-evolution. Host adaptation to vertically passaged viruses was traded-off against reduced resistance to the non-evolved viruses. Thus, we provide evidence of the key role that the interplay between mode of transmission and host-parasite co-evolution has in determining the evolution of virulence. Virulence is a key property of parasites, and is linked to the emergence of new diseases and to the reduction of ecosystem biodiversity. Consequently, scientists have devoted a great effort to build theoretical models that predict which factors may modulate virulence evolution. However, whether (and how) these factors affect virulence evolution has been seldom analysed experimentally. Using the plant virus Cucumber mosaic virus (CMV) and its natural host Arabidopsis thaliana, we studied the role of two such factors: the mode of transmission, and host adaptation in response to parasite evolution. We serially passaged CMV under strict vertical and strict horizontal transmission, and a combination of both. Subsequently, we analysed differences in CMV seed (vertical) transmission rate, accumulation and virulence between evolved and non-evolved viruses. We also compared whether these differences varied in original plants and in plants evolved during vertical passaging. Vertical passaging increased CMV seed transmission, and reduced accumulation and virulence, while horizontal passaging had no effect. Changes during vertical passaging were determined also by reciprocal host adaptation, which additionally reduced virulence and accumulation of vertically transmitted viruses. Hence, we provide evidence that the interplay between the transmission mode and host-parasite co-evolution is central in determining virulence evolution.
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Affiliation(s)
- Israel Pagán
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA) and Departamento de Biotecnología, Campus Montegancedo, Universidad Politécnica de Madrid. Pozuelo de Alarcón, Madrid, Spain
| | - Nuria Montes
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA) and Departamento de Biotecnología, Campus Montegancedo, Universidad Politécnica de Madrid. Pozuelo de Alarcón, Madrid, Spain
| | - Michael G Milgroom
- Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York, United States of America
| | - Fernando García-Arenal
- Centro de Biotecnología y Genómica de Plantas (UPM-INIA) and Departamento de Biotecnología, Campus Montegancedo, Universidad Politécnica de Madrid. Pozuelo de Alarcón, Madrid, Spain
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Daş G, Gauly M. Density related effects on lifetime fecundity of Heterakis gallinarum in chickens. Parasit Vectors 2014; 7:334. [PMID: 25034471 PMCID: PMC4223411 DOI: 10.1186/1756-3305-7-334] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Accepted: 07/02/2014] [Indexed: 11/21/2022] Open
Abstract
Background Density related effects, both inverse density- and density-dependent, contribute to regulating population dynamics of parasites. We investigated whether density related effects are directly controlling lifetime fecundity of Heterakis gallinarum. Methods Daily total numbers of H. gallinarum eggs in faeces samples (N = 1365) from chickens (N = 39) were quantified starting from 3 weeks (wk) post-infection (p.i.). The birds were necropsied 8 wk p.i., and intensity and demographic characteristics of infrapopulations were determined. Density related effects on cumulative egg excretion (CEE), lifetime fecundity and worm length were investigated with a segmented regression analysis. Results For CEE, lifetime fecundity and female worm length, we determined highly similar parasite intensity thresholds (52–54 worms), which separated infrapopulations for influences of inverse density- and density dependence. CEE increased as parasite intensity increased up to an intensity of 52 worms. After this threshold, the relationship followed more of a horizontal line indicating impaired worm fecundity at higher parasite intensities. Lifetime fecundity was enhanced linearly in infrapopulations with up to 54 worms, but thereafter decreased gradually with increasing infrapopulation size. Female worm length increased linearly with elevating parasite intensity up to a threshold of 54 worms and thereafter declined with a rate of -0.014 mm for each additional worm. Lifetime fecundity and female worm length did not significantly differ between infrapopulations below and above the thresholds (P > 0.05). Lifetime fecundity was positively associated with the percentage of male worms (r = 0.44; P < 0.001), but negatively with absolute deviation from the theoretically expected sex-ratio in the infrapopulations (r = -0.56; P = 0.005). These relationships were stronger in infrapopulations below the threshold (r = 0.51 and -0.61, respectively), and were not significantly different from zero in the infrapopulations above the threshold (P > 0.05). Conclusions Egg production of H. gallinarum is regulated by the effects of both inverse density- and density-dependent mechanisms, which result in similar average lifetime fecundity below or above intensity thresholds. In infrapopulations below the intensity thresholds, inverse density dependence effects on lifetime fecundity appear to result partly from sex-ratio fluctuations and impaired mating success of the nematode.
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Affiliation(s)
- Gürbüz Daş
- University of Göttingen, Department of Animal Sciences, Albrecht-Thaer-Weg 3, 37075 Göttingen, Germany.
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Exclusion and spatial segregation in the apparent competition between two hosts sharing macroparasites. Theor Popul Biol 2013; 86:12-22. [DOI: 10.1016/j.tpb.2013.03.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Revised: 02/09/2013] [Accepted: 03/01/2013] [Indexed: 11/22/2022]
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Wisz MS, Pottier J, Kissling WD, Pellissier L, Lenoir J, Damgaard CF, Dormann CF, Forchhammer MC, Grytnes JA, Guisan A, Heikkinen RK, Høye TT, Kühn I, Luoto M, Maiorano L, Nilsson MC, Normand S, Öckinger E, Schmidt NM, Termansen M, Timmermann A, Wardle DA, Aastrup P, Svenning JC. The role of biotic interactions in shaping distributions and realised assemblages of species: implications for species distribution modelling. Biol Rev Camb Philos Soc 2013; 88:15-30. [PMID: 22686347 PMCID: PMC3561684 DOI: 10.1111/j.1469-185x.2012.00235.x] [Citation(s) in RCA: 610] [Impact Index Per Article: 55.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Revised: 05/11/2012] [Accepted: 05/11/2012] [Indexed: 12/05/2022]
Abstract
Predicting which species will occur together in the future, and where, remains one of the greatest challenges in ecology, and requires a sound understanding of how the abiotic and biotic environments interact with dispersal processes and history across scales. Biotic interactions and their dynamics influence species' relationships to climate, and this also has important implications for predicting future distributions of species. It is already well accepted that biotic interactions shape species' spatial distributions at local spatial extents, but the role of these interactions beyond local extents (e.g. 10 km(2) to global extents) are usually dismissed as unimportant. In this review we consolidate evidence for how biotic interactions shape species distributions beyond local extents and review methods for integrating biotic interactions into species distribution modelling tools. Drawing upon evidence from contemporary and palaeoecological studies of individual species ranges, functional groups, and species richness patterns, we show that biotic interactions have clearly left their mark on species distributions and realised assemblages of species across all spatial extents. We demonstrate this with examples from within and across trophic groups. A range of species distribution modelling tools is available to quantify species environmental relationships and predict species occurrence, such as: (i) integrating pairwise dependencies, (ii) using integrative predictors, and (iii) hybridising species distribution models (SDMs) with dynamic models. These methods have typically only been applied to interacting pairs of species at a single time, require a priori ecological knowledge about which species interact, and due to data paucity must assume that biotic interactions are constant in space and time. To better inform the future development of these models across spatial scales, we call for accelerated collection of spatially and temporally explicit species data. Ideally, these data should be sampled to reflect variation in the underlying environment across large spatial extents, and at fine spatial resolution. Simplified ecosystems where there are relatively few interacting species and sometimes a wealth of existing ecosystem monitoring data (e.g. arctic, alpine or island habitats) offer settings where the development of modelling tools that account for biotic interactions may be less difficult than elsewhere.
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Affiliation(s)
- Mary Susanne Wisz
- Department of Bioscience, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark.
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Abstract
Past models have suggested host-parasite coextinction could lead to linear, or concave down relationships between free-living species richness and parasite richness. I explored several models for the relationship between parasite richness and biodiversity loss. Life cycle complexity, low generality of parasites and sensitivity of hosts reduced the robustness of parasite species to the loss of free-living species diversity. Food-web complexity and the ordering of extinctions altered these relationships in unpredictable ways. Each disassembly of a food web resulted in a unique relationship between parasite richness and the richness of free-living species, because the extinction trajectory of parasites was sensitive to the order of extinctions of free-living species. However, the average of many disassemblies tended to approximate an analytical model. Parasites of specialist hosts and hosts higher on food chains were more likely to go extinct in food-web models. Furthermore, correlated extinctions between hosts and parasites (e.g. if parasites share a host with a specialist predator) led to steeper declines in parasite richness with biodiversity loss. In empirical food webs with random removals of free-living species, the relationship between free-living species richness and parasite richness was, on average, quasi-linear, suggesting biodiversity loss reduces parasite diversity more than previously thought.
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Affiliation(s)
- Kevin D Lafferty
- Western Ecological Research Center, US Geological Survey, c/o Marine Science Institute, University of California, Santa Barbara, CA 93106, USA.
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22
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Dunn AM, Torchin ME, Hatcher MJ, Kotanen PM, Blumenthal DM, Byers JE, Coon CA, Frankel VM, Holt RD, Hufbauer RA, Kanarek AR, Schierenbeck KA, Wolfe LM, Perkins SE. Indirect effects of parasites in invasions. Funct Ecol 2012. [DOI: 10.1111/j.1365-2435.2012.02041.x] [Citation(s) in RCA: 150] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Alison M. Dunn
- Faculty of Biological Sciences; University of Leeds; Leeds LS2 9JT UK
| | - Mark E. Torchin
- Smithsonian Tropical Research Institute; Apartado 0843-03092 Balboa Ancon Republic of Panama
| | - Melanie J. Hatcher
- Faculty of Biological Sciences; University of Leeds; Leeds LS2 9JT UK
- School of Biological Sciences; University of Bristol; Bristol BS8 1UG UK
| | - Peter M. Kotanen
- Department of Ecology and Evolutionary Biology; University of Toronto Mississauga; 3359 Mississauga Road North Mississauga Ontario L5L 1C6 Canada
| | - Dana M. Blumenthal
- Rangeland Resources Research Unit; USDA Agricultural Research Service; Fort Collins Colorado 80526 USA
| | - James E. Byers
- Odum School of Ecology; University of Georgia; Athens Georgia 30602 USA
| | - Courtney A.C. Coon
- Department of Integrative Biology; University of South Florida; Tampa Florida 33620 USA
| | - Victor M. Frankel
- Smithsonian Tropical Research Institute; Apartado 0843-03092 Balboa Ancon Republic of Panama
- Department of Biology & Redpath Museum; McGill University; Montreal Quebec H3A 2K6 Canada
| | - Robert D. Holt
- Department of Biology; University of Florida; Gainesville Florida 32611 USA
| | - Ruth A. Hufbauer
- Department of Bioagricultural Sciences and Pest Management, and Graduate Degree Program in Ecology; Colorado State University; Fort Collins Colorado 80523 USA
| | - Andrew R. Kanarek
- National Institute for Mathematical and Biological Synthesis; University of Tennessee; Knoxville Tennessee 37996-1527 USA
| | | | - Lorne M. Wolfe
- Department of Biology; Georgia Southern University; Statesboro GA 30460 USA
| | - Sarah E. Perkins
- Cardiff School of Biosciences; Biomedical Sciences Building Museum Avenue Cardiff CF10 3AX UK
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Draycott RAH, Santos JÁA. Intestinal nematodes of shot wild grey partridges in Norfolk, England. Vet Rec 2012; 171:20. [PMID: 22678618 DOI: 10.1136/vr.100753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- R A H Draycott
- Game & Wildlife Conservation Trust, Fordingbridge, Hampshire SP6 1EF, UK.
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Orledge JM, Blount JD, Hoodless AN, Royle NJ. Antioxidant supplementation during early development reduces parasite load but does not affect sexual ornament expression in adult ring-necked pheasants. Funct Ecol 2012. [DOI: 10.1111/j.1365-2435.2012.01977.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Abstract
In this article, we summarize the major scientific developments of the last decade on the transmission of infectious agents in multi-host systems. Almost sixty percent of the pathogens that have emerged in humans during the last 30-40 years are of animal origin and about sixty percent of them show an important variety of host species besides humans (3 or more possible host species). In this review, we focus on zoonotic infections with vector-borne transmission and dissect the contrasting effects that a multiplicity of host reservoirs and vectors can have on their disease dynamics. We discuss the effects exerted by host and vector species richness and composition on pathogen prevalence (i.e., reduction, including the dilution effect, or amplification). We emphasize that, in multiple host systems and for vector-borne zoonotic pathogens, host reservoir species and vector species can exert contrasting effect locally. The outcome on disease dynamics (reduced pathogen prevalence in vectors when the host reservoir species is rich and increased pathogen prevalence when the vector species richness increases) may be highly heterogeneous in both space and time. We then ask briefly how a shift towards a more systemic perspective in the study of emerging infectious diseases, which are driven by a multiplicity of hosts, may stimulate further research developments. Finally, we propose some research avenues that take better into account the multi-host species reality in the transmission of the most important emerging infectious diseases, and, particularly, suggest, as a possible orientation, the careful assessment of the life-history characteristics of hosts and vectors in a community ecology-based perspective.
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Affiliation(s)
- Benjamin Roche
- UMI 209 UMMISCO, IRD-université Pierre-et-Marie-Curie, 32, avenue Henri-Varagnat, 93143 Bondy cedex, France
| | - Jean-François Guégan
- UMR MIVEGEC IRD 224, CNRS 5230, centre IRD de Montpellier, universités de Montpellier I et II, BP 64501, 34394 Montpellier, cedex 5, France
- École des hautes études en santé publique, Interdisciplinary Research Centre on Biodiversity, Climate Change and Infectious Diseases, centre IRD de Montpellier, BP 64501, 34394 Montpellier cedex 5, France
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Tompkins DM, Dunn AM, Smith MJ, Telfer S. Wildlife diseases: from individuals to ecosystems. J Anim Ecol 2010; 80:19-38. [PMID: 20735792 DOI: 10.1111/j.1365-2656.2010.01742.x] [Citation(s) in RCA: 274] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
1. We review our ecological understanding of wildlife infectious diseases from the individual host to the ecosystem scale, highlighting where conceptual thinking lacks verification, discussing difficulties and challenges, and offering potential future research directions. 2. New molecular approaches hold potential to increase our understanding of parasite interactions within hosts. Also, advances in our knowledge of immune systems makes immunological parameters viable measures of parasite exposure, and useful tools for improving our understanding of causal mechanisms. 3. Studies of transmission dynamics have revealed the importance of heterogeneity in host behaviour and physiology, and of contact processes operating at different spatial and temporal scales. An important future challenge is to determine the key transmission mechanisms maintaining the persistence of different types of diseases in the wild. 4. Regulation of host populations is too complex to consider parasite effects in isolation from other factors. One solution is to seek a unified understanding of the conditions under which (and the ecological rules determining when) population scale impacts of parasites can occur. 5. Good evidence now shows that both direct effects of parasites, and trait mediated indirect effects, frequently mediate the success of invasive species and their impacts on recipient communities. A wider exploration of these effects is now needed. 6. At the ecosystem scale, research is needed to characterize the circumstances and conditions under which both fluxes in parasite biomass, and trait mediated effects, are significant in ecosystem processes, and to demonstrate that parasites do indeed increase 'ecosystem health'. 7. There is a general need for more empirical testing of predictions and subsequent development of theory in the classic research cycle. Experimental field studies, meta-analyses, the collection and analysis of long-term data sets, and data constrained modelling, will all be key to advancing our understanding. 8. Finally, we are only now beginning to understand the importance of cross-scale interactions associated with parasitism. Such interactions may offer key insights into bigger picture questions such as when and how different regulatory factors are important, when disease can cause species extinctions, and what characteristics are indicative of functionally resilient ecosystems.
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Ricklefs RE. Host-pathogen coevolution, secondary sympatry and species diversification. Philos Trans R Soc Lond B Biol Sci 2010; 365:1139-47. [PMID: 20194175 DOI: 10.1098/rstb.2009.0279] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The build-up of species locally within a region by allopatric speciation depends on geographically separated (allopatric) sister populations becoming reproductively incompatible followed by secondary sympatry. Among birds, this has happened frequently in remote archipelagos, spectacular cases including the Darwin's finches (Geospizinae) and Hawaiian honeycreepers (Drepanidinae), but similar examples are lacking in archipelagos nearer to continental landmasses. Of the required steps in the speciation cycle, achievement of secondary sympatry appears to be limiting in near archipelagos and, by extension, in continental regions. Here, I suggest that secondary sympatry might be prevented by apparent competition mediated through pathogens that are locally coevolved with one population of host and are pathogenic in sister populations. The absence of numerous pathogens in remote archipelagos might, therefore, allow sister populations to achieve secondary sympatry more readily and thereby accelerate diversification. By similar reasoning, species should accumulate relatively slowly within continental regions. In this essay, I explore the assumptions and some implications of this model for species diversification.
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Affiliation(s)
- Robert E Ricklefs
- Department of Biology, University of Missouri-St Louis, One University Boulevard, St Louis, MO 63121-4499, USA.
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29
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Goodenough A. Are the ecological impacts of alien species misrepresented? A review of the “native good, alien bad” philosophy. COMMUNITY ECOL 2010. [DOI: 10.1556/comec.11.2010.1.3] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Effect of sexual segregation on host-parasite interaction: model simulation for abomasal parasite dynamics in alpine ibex (Capraibex). Int J Parasitol 2010; 40:1285-93. [PMID: 20430029 DOI: 10.1016/j.ijpara.2010.03.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Revised: 03/08/2010] [Accepted: 03/23/2010] [Indexed: 11/24/2022]
Abstract
We investigated whether sexual segregation might affect parasite transmission and host dynamics, hypothesising that if males are the more heavily infected sex and more responsible for the transmission of parasite infections, female avoidance of males and the space they occupy could reduce infection rates. A mathematical model, simulating the interaction between abomasal parasites and a hypothetical alpine ibex (Capraibex) host population composed of its two sexes, was developed to predict the effect of different degrees of sexual segregation on parasite intensity and on host abundance. The results showed that when females tended to be segregated from males, and males were distributed randomly across space, the impact of parasites was the lowest, resulting in the highest host abundance, with each sex having the lowest parasite intensity. The predicted condition that minimises the impact of parasites in our model was the one closest to that observed in nature where females actively seek out the more segregated sites while males are less selective in their ranging behaviour. The overlapping of field observation with the predicted optimal strategy lends support to our idea that there might be a connection between parasite transmission and sexual segregation. Our simulations provide the biological boundaries of host-parasite interaction needed to determine a parasite-mediated effect on sexual segregation and a formalised null hypothesis against which to test future field experiments.
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VANAK ABITAMIM, GOMPPER MATTHEWE. Dogs
Canis familiaris
as carnivores: their role and function in intraguild competition. Mamm Rev 2009. [DOI: 10.1111/j.1365-2907.2009.00148.x] [Citation(s) in RCA: 196] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - MATTHEW E. GOMPPER
- Department of Fisheries and Wildlife Sciences, University of Missouri, Columbia, MO 65211, USA
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32
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Decline and potential recovery of the European grey partridge (Perdix perdix) population—a review. EUR J WILDLIFE RES 2009. [DOI: 10.1007/s10344-009-0311-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Potts GR. Long-term changes in the prevalences of caecal nematodes and histomonosis in gamebirds in the UK and the interaction with poultry. Vet Rec 2009; 164:715-8. [PMID: 19502627 DOI: 10.1136/vr.164.23.715] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
From 1912 to 2003, 12,056 grey and red-legged partridges and pheasants found dead in the UK were examined. The trends in their infection rates with Heterakis species and histomonosis were strongly correlated among wild, pen-reared, young and adult partridges and young pen-reared pheasants but not adult pheasants. Except among the adult pheasants, the prevalence of Heterakis declined by 91 per cent to 100 per cent from 1952 to 1991. Heterakis isolonche was found predominantly in pheasants but only until the 1960s. Histomonosis declined relative to Heterakis species infections after the introduction of dimetridazole. There was a long-term change in the prevalence of Heterakis, with changes in domestic fowl husbandry being suggested as the cause.
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Affiliation(s)
- G R Potts
- The Game and Wildlife Conservation Trust, Fordingbridge, Hampshire SP6 1EF.
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34
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Kelly DW, Paterson RA, Townsend CR, Poulin R, Tompkins DM. Parasite spillback: A neglected concept in invasion ecology? Ecology 2009; 90:2047-56. [PMID: 19739367 DOI: 10.1890/08-1085.1] [Citation(s) in RCA: 321] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- D W Kelly
- Landcare Research, 764 Cumberland Street, Private Bag 1930, Dunedin 9054, New Zealand.
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Abstract
To date, ecologists and conservation biologists have focused much of their attention on the population and ecosystem effects of disease at regional scales and the role that diseases play in global species extinction. Far less research has been dedicated to identifying the effects that diseases can have on local scale species assemblages. We examined the role of infectious disease in structuring local biodiversity. Our intention was to illustrate how variable outcomes can occur by focusing on three case studies: the influence of chestnut blight on forest communities dominated by chestnut trees, the influence of red-spot disease on urchin barrens and kelp forests, and the influence of sylvatic plague on grassland communities inhabited by prairie dogs. Our findings reveal that at local scales infectious disease seems to play an important, though unpredictable, role in structuring species diversity. Through our case studies, we have shown that diseases can cause drastic population declines or local extirpations in keystone species, ecosystem engineers, and otherwise abundant species. These changes in local diversity may be very important, particularly when considered alongside potentially corresponding changes in community structure and function, and we believe that future efforts to understand the importance of disease to species diversity should have an increased focus on these local scales.
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Affiliation(s)
- Katherine F Smith
- Brown University, Ecology and Evolutionary Biology, Providence, RI 02912, USA.
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Virulence, cultivating conditions, and phylogenetic analyses of oomycete parasites in Daphnia. Parasitology 2008; 135:1667-78. [PMID: 18992181 DOI: 10.1017/s0031182008005052] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
We describe the infectivity, virulence, cultivating conditions, and phylogenetic positions of naturally occurring oomycete parasites of Daphnia, invertebrates which play a major role in aquatic food webs. Daphnia pulex individuals were found dead and covered by oomycete mycelia when exposed to pond sediments. We were able to extract 4 oomycete isolates from dead Daphnia and successfully cultivate them. Using the ITS and LSU rDNA sequences, we further showed these isolates to be distinct species. The isolates were experimentally demonstrated to be parasitic and not saprobic. After exposure to the parasites, Daphnia mortality was much higher than that reported for Daphnia infected with other known parasite species. Therefore, it is likely that oomycete parasites are important selective pressures in natural Daphnia populations. Moreover, their close phylogenetic relationship to parasites of fish and algae suggests that the stability of aquatic food webs (i.e. fish-Daphnia-algae) might be influenced by the shared parasite communities.
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Antonovics J, Hood M, Partain J. The ecology and genetics of a host shift: microbotryum as a model system. Am Nat 2008; 160 Suppl 4:S40-53. [PMID: 18707452 DOI: 10.1086/342143] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The need to prevent and cure emerging diseases often precludes their continuing study in situ. We present studies on the process of disease emergence by host shifts using the model system of anther-smut disease (Microbotryum violaceum) on the plant genus Silene (Caryophyllaceae). This system has little direct social impact, and it is readily amenable to experimental manipulation. Our microevolutionary studies have focused on the host shift of Microbotryum from Silene alba (=latifolia; white campion) onto Silene vulgaris (bladder campion) in a population in Virginia. Karyotypic variation shows that the host shift is recent and originates from the disease on sympatric S. alba. Analysis of the spatial pattern of disease shows that the host shift has been contingent on the co-occurrence of the two species at a local scale. Cross-inoculation studies show that families of the new host differ greatly in their susceptibility to the pathogen, indicating the potential for rapid evolution of resistance. Disease expression on the new host is frequently abnormal, suggesting that the pathogen is imperfectly adapted to its new host. In experimental populations, disease transmission within populations of the old host is greater than within populations of the new host. However, there is also a high transmission rate of the disease from the new host back to the old host, suggesting a feedback effect that increases disease prevalence in the community as a whole. Continuing studies of these populations are designed to determine whether this new host-pathogen system is likely to be self-sustaining and to quantify evolutionary changes in both the host and the pathogen.
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Affiliation(s)
- Janis Antonovics
- Department of Biology, University of Virginia, Charlottesville, Virginia 22904, USA
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Pagán I, Alonso-Blanco C, García-Arenal F. Host responses in life-history traits and tolerance to virus infection in Arabidopsis thaliana. PLoS Pathog 2008; 4:e1000124. [PMID: 18704166 PMCID: PMC2494869 DOI: 10.1371/journal.ppat.1000124] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2007] [Accepted: 07/14/2008] [Indexed: 11/19/2022] Open
Abstract
Knowing how hosts respond to parasite infection is paramount in understanding the effects of parasites on host populations and hence host–parasite co-evolution. Modification of life-history traits in response to parasitism has received less attention than other defence strategies. Life-history theory predicts that parasitised hosts will increase reproductive effort and accelerate reproduction. However, empirical analyses of these predictions are few and mostly limited to animal-parasite systems. We have analysed life-history trait responses in 18 accessions of Arabidopsis thaliana infected at two different developmental stages with three strains of Cucumber mosaic virus (CMV). Accessions were divided into two groups according to allometric relationships; these groups differed also in their tolerance to CMV infection. Life-history trait modification upon virus infection depended on the host genotype and the stage at infection. While all accessions delayed flowering, only the more tolerant allometric group modified resource allocation to increase the production of reproductive structures and progeny, and reduced the length of reproductive period. Our results are in agreement with modifications of life-history traits reported for parasitised animals and with predictions from life-history theory. Thus, we provide empirical support for the general validity of theoretical predictions. In addition, this experimental approach allowed us to quantitatively estimate the genetic determinism of life-history trait plasticity and to evaluate the role of life-history trait modification in defence against parasites, two largely unexplored issues. Hosts have developed a variety of mechanisms to compensate for the negative impact of parasite infection. Modification of life-history traits in response to parasitism has received less attention than other defence strategies. Life-history theory assumes trade-offs between resource allocation to different fitness components, and predicts that hosts under parasitism will allocate more resources to reproduction, subtracting them from those dedicated to growth and survival. Empirical support for predictions is not abundant, and derives mostly from the analysis of animal-parasite systems. We have analysed the modification of various life-history traits in the plant Arabidopsis thaliana infected by Cucumber mosaic virus. Life-history trait modification upon virus infection depended on the host genotype and on the developmental stage at infection. All plant genotypes delayed flowering, but only the more tolerant ones allocated more resources to reproduction, and reduced the length of reproductive period. These results agree with reports from parasitised animals and with predictions from life-history theory, providing empirical support for the general validity of theoretical predictions. In addition, results allow for the more precise evaluation of the role of life-history trait modification in defence against parasites by taking into account plant–virus interactions where life-history traits were differentially modified.
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Affiliation(s)
- Israel Pagán
- Departamento de Biotecnología, E.T.S.I. Agrónomos and Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid, Madrid, Spain
| | - Carlos Alonso-Blanco
- Departamento de Genética Molecular de Plantas, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Madrid, Spain
| | - Fernando García-Arenal
- Departamento de Biotecnología, E.T.S.I. Agrónomos and Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid, Madrid, Spain
- * E-mail:
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Georgiev BB, Sánchez MI, Vasileva GP, Nikolov PN, Green AJ. Cestode parasitism in invasive and native brine shrimps (Artemia spp.) as a possible factor promoting the rapid invasion of A. franciscana in the Mediterranean region. Parasitol Res 2007; 101:1647-55. [PMID: 17712569 DOI: 10.1007/s00436-007-0708-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2007] [Accepted: 07/30/2007] [Indexed: 11/30/2022]
Abstract
Artemia franciscana is an invasive crustacean expanding its range in hypersaline wetlands in the Mediterranean region and replacing native Artemia parthenogenetica and Artemia salina. Native brine shrimps are known as intermediate hosts of cestodes; infected individuals exhibit changes in their behaviour and appearance, thus facilitating the parasite transmission to the avian hosts by predation. To assess whether invasive brine shrimps participate in the cestode life cycles to the same extent as the native species, we examined the natural infections in seven populations of Artemia spp. along the southern coast of Spain and Portugal: three populations of each A. franciscana and A. parthenogenetica and one population of A. salina. Ten cestode species were found in A. parthenogenetica, while only six were recorded in each of A. salina and A. franciscana. The overall infection was consistently higher in native than in invasive populations. For a particular cestode species, the prevalence or abundance was significantly higher in a native population for 54 pairwise comparisons and only higher for an invasive population for 4 pairwise comparisons. These results suggest that cestodes may influence competitive interactions between native and invasive brine shrimps, thus partly explaining the invasive success of A. franciscana.
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Affiliation(s)
- B B Georgiev
- Central Laboratory of General Ecology, Bulgarian Academy of Sciences, 2 Gagarin Street, 1113 Sofia, Bulgaria.
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Ricklefs RE, Bermingham E. The Causes of Evolutionary Radiations in Archipelagoes: Passerine Birds in the Lesser Antilles. Am Nat 2007; 169:285-97. [PMID: 17230401 DOI: 10.1086/510730] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2006] [Accepted: 10/10/2006] [Indexed: 11/03/2022]
Abstract
To investigate why some lineages undergo evolutionary radiation, we compare the passerine avifaunas of the Hawaiian and Galapagos archipelagoes, which have supported well-known radiations of birds, with those of the Lesser Antilles, which have not. We focus on four steps required for the buildup of diversity through allopatric speciation and secondary sympatry: genetic divergence in isolation, persistence of island populations, recolonization of source islands, and ecological compatibility in secondary sympatry. Analysis of genetic divergence among island populations in the Lesser Antilles reveals evidence of both prolonged independent evolution and re-expansion of differentiated island populations through the archipelago but little evidence of secondary sympatry of divergent genetic lineages. Archipelagoes with high rates of colonization from continental or nearby large-island sources might fail to promote evolutionary radiations because colonists fill ecological space and constrain diversification through competition. However, morphological analysis demonstrated similar divergence between allopatric populations in species in Hawaii, Galapagos, and the Lesser Antilles, although the rate of divergence between secondarily sympatric species evidently is more rapid in Hawaii and the Galapagos. Alternatively, endemic buildup of diversity might be facilitated by the relative absence of pathogens in Hawaii and Galapagos that otherwise could prevent the secondary sympatry of populations owing to disease-mediated competition.
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Affiliation(s)
- Robert E Ricklefs
- Department of Biology, University of Missouri, St. Louis, Missouri 63121-4499, USA.
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41
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Abstract
The dynamics of any infectious disease are heavily dependent on the rate of transmission from infectious to susceptible hosts. In many disease models, this rate is captured in a single compound parameter, the probability of transmission P. However, closer examination reveals how beta can be further decomposed into a number of biologically relevant variables, including contact rates among individuals and the probability that contact events actually result in disease transmission. We start by introducing some of the basic concepts underlying the different approaches to modeling disease transmission and by laying out why a more detailed understanding of the variables involved is usually desirable. We then describe how parameter estimates of these variables can be derived from empirical data, drawing primarily from the existing literature on human diseases. Finally, we discuss how these concepts and approaches may be applied to the study of pathogen transmission in wildlife diseases. In particular, we highlight recent technical innovations that could help to overcome some the logistical challenges commonly associated with empirical disease research in wild populations.
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Affiliation(s)
- James E. Childs
- Department of Epidemiology and Public Health and Center for Eco-Epidemiolog, Yale University School of Medicine, 60 College St, 208034, 06520-8034 New Haven, CT USA
| | - John S. Mackenzie
- Centre for Emerging Infectious Diseases, Australian Biosecurity Cooperative Research Centre, Curtin University of Technology, U1987, 6845 Perth, WA Australia
| | - Jürgen A. Richt
- Virus and Prion Diseases of Livestock Research Unit, National Animal Disease Center USDA, 2300 Dayton Ave Ames, 50010 IA USA
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Ferrari N, Rosà R, Pugliese A, Hudson PJ. The role of sex in parasite dynamics: model simulations on transmission of Heligmosomoides polygyrus in populations of yellow-necked mice, Apodemus flavicollis. Int J Parasitol 2006; 37:341-9. [PMID: 17188276 DOI: 10.1016/j.ijpara.2006.10.015] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2006] [Revised: 10/16/2006] [Accepted: 10/19/2006] [Indexed: 11/23/2022]
Abstract
We investigated possible mechanisms that could cause sex-biased parasite transmission of the helminth Heligmosomoides polygyrus in its rodent host, Apodemus flavicollis, using a modelling approach. Two, not mutually exclusive, hypotheses were examined: that sex-biased parasite transmission is caused by differences in immunity that influence the success of free-living stages and/or is caused by sex differences in host behaviour and the dissemination of infective stages. Model simulations were compared with results from a field manipulation experiment of H. polygyrus in replicated populations of A. flavicollis. Simulations predicted the experimental field results, and both hypotheses explained the pattern observed. Transmission is male-biased if a male immune response increases fertility, hatching or survival of free-living stages. Alternatively, transmission is male-biased if their behavioural characteristics allow them to spread infective larvae in areas more frequently used by females. These results highlight that host sex is not only responsible for differences in parasite susceptibility, but may profoundly influence host-parasite interactions, resulting in a sex bias in parasite transmission.
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Affiliation(s)
- N Ferrari
- Dipartimento di Patologia Animale, Igiene e Sanità Pubblica Veterinaria, Università degli Studi di Milano, Via Celoria, 10, 20133 Milano, Italy.
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Abstract
We present a synthesis of empirical and theoretical work investigating how parasites influence competitive and predatory interactions between other species. We examine the direct and indirect effects of parasitism and discuss examples of density and parasite-induced trait-mediated effects. Recent work reveals previously unrecognized complexity in parasite-mediated interactions. In addition to parasite-modified and apparent competition leading to species exclusion or enabling coexistence, parasites and predators interact in different ways to regulate or destablize the population dynamics of their joint prey. An emerging area is the impact of parasites on intraguild predation (IGP). Parasites can increase vulnerability of infected individuals to cannibalism or predation resulting in reversed species dominance in IGP hierarchies. We discuss the potential significance of parasites for community structure and biodiversity, in particular their role in promoting species exclusion or coexistence and the impact of emerging diseases. Ongoing invasions provide examples where parasites mediate native/invader interactions and play a key role in determining the outcome of invasions. We highlight the need for more quantitative data to assess the impact of parasites on communities, and the combination of theoretical and empirical studies to examine how the effects of parasitism scale up to community-level processes.
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Affiliation(s)
- Melanie J Hatcher
- School of Biological Sciences, University of Bristol, Woodland Road, Bristol BS8 1UG, UK
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44
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Carlsson-Granér U. Disease dynamics, host specificity and pathogen persistence in isolated host populations. OIKOS 2006. [DOI: 10.1111/j.0030-1299.2006.13292.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Mouritsen KN, Tompkins DM, Poulin R. Climate warming may cause a parasite-induced collapse in coastal amphipod populations. Oecologia 2005; 146:476-83. [PMID: 16133194 DOI: 10.1007/s00442-005-0223-0] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2005] [Accepted: 07/19/2005] [Indexed: 11/28/2022]
Abstract
Besides the direct impact on the general performance of individual organisms, the ecological consequences of climate change in terrestrial and marine ecosystems are expected to be determined by complex cascading effects arising from modified trophic interactions and competitive relationships. Recently, the synergistic effect of parasitism and climate change has been emphasised as potentially important to host population dynamics and community structure, but robust empirical evidence is generally lacking. The amphipod Corophium volutator is an ecologically important species in coastal soft-bottom habitats of the temperate North Atlantic, and commonly serves as host to microphallid trematodes that cause intensity-dependent and temperature-dependent mortality in the amphipod population. Using a simulation model parameterised with experimental and field data, we demonstrate that a 3.8 degrees C increase in ambient temperature will likely result in a parasite-induced collapse of the amphipod population. This temperature increase is well within the range predicted to prevail by the year 2075 in the International Wadden Sea region from where the model data are obtained. Due to the amphipods' ecological importance, their population decline may impact the coastal ecosystem as a whole.
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Affiliation(s)
- Kim N Mouritsen
- Department of Marine Ecology, Institute of Biological Sciences, University of Aarhus, Finlandsgade 14, 8200 Aarhus N, Denmark.
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46
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CALEY PETER, HONE JIM. Assessing the host disease status of wildlife and the implications for disease control: Mycobacterium bovis infection in feral ferrets. J Appl Ecol 2005. [DOI: 10.1111/j.1365-2664.2005.01053.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Chalvet-Monfray K, Sabatier P, Chauve C, Zenner L. A Mathematical Model of the Population Dynamics of Heterakis Gallinarum in Turkeys (Meleagridis Gallopavo). Poult Sci 2004; 83:1629-35. [PMID: 15510545 DOI: 10.1093/ps/83.10.1629] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Heterakis gallinarum is a relatively nonpathogenic organism, but it is important as the transport host for the pathogenic protozoan Histomonas meleagridis. A mathematical model was developed to describe the population dynamics of Heterakis gallinarum in a turkey flock to study its kinetics in a number of hosts. The model includes quantitative (parasite burden) and qualitative (number of hosts without mature parasite) descriptions of these dynamics. To understand the role of Heterakis as a transport host, the various elements that delay the beginning of development of the parasite population (e.g., necessary delay of larval stage, the probability of having a male and female in the same host) were taken into account. From published data, the negative binomial distribution parameter k = 0.24, which described the aggregated distribution of the Heterakis among the hosts, was calculated. The sensibility study showed that when the k parameter decreased (i.e., when the population was more aggregated), infestation increased quantitatively (mean parasite burden increased) but not qualitatively (the number of host without mature parasite increased). The model demonstrated that the population dynamics of Heterakis takes time; for instance, with an aggregated population of Heterakis at d 90, the host is mainly free of adult parasite. These results may be used in the future to test the role of Heterakis in the spread of Histomonas.
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Affiliation(s)
- K Chalvet-Monfray
- Unité Environnement et Prévision de la Santé des Populations, Equipe BioMathématiques et Epidémiologie (USC INRA/ENVL), France.
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De Leo GA, Focardi S, Gatto M, Cattadori IM. The decline of the grey partridge in Europe: comparing demographies in traditional and modern agricultural landscapes. Ecol Modell 2004. [DOI: 10.1016/j.ecolmodel.2003.11.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Wodarz D, Sasaki A. Apparent competition and recovery from infection. J Theor Biol 2004; 227:403-12. [PMID: 15019507 DOI: 10.1016/j.jtbi.2003.11.027] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2003] [Revised: 10/06/2003] [Accepted: 11/17/2003] [Indexed: 11/16/2022]
Abstract
We use mathematical models to analyse how the recovery rate from infection influences the fitness of a host in a setting of interspecific competition. We show that sub-optimal immunity against pathogens can be advantageous for the host in the presence of cross-species infection. Weaker immunity allows the parasite to be used as a biological weapon, and this increases the fitness of the host relative to a competitor. A parameter region is observed in which the outcome of competition depends on the initial conditions. We extend this model and consider the dynamics in a spatial setting and find that the outcome depends on the migration rate of the host species. At low migration rates, coexistence of the host species is possible across space. For higher migration rates, the host species characterized by a lower recovery rate can invade the territory of its competitor. Finally, we study these dynamics in an evolutionary setting. Although a lower recovery rate from infection can increase the competitive ability of a species, we find that evolution maximizes the recovery rate and minimizes parasite burden. The models presented are related to the concept of apparent competition, and our results are discussed in relation to both theoretical and empirical studies.
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Affiliation(s)
- Dominik Wodarz
- Department of Ecology and Evolutionary Biology, Steinhaus Hall, University of California, Irvine, CA 92697, USA.
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50
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Caley P, Hone J. Disease transmission between and within species, and the implications for disease control. J Appl Ecol 2004. [DOI: 10.1111/j.1365-2664.2004.00867.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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