1
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Stroud JT, Delory BM, Barnes EM, Chase JM, De Meester L, Dieskau J, Grainger TN, Halliday FW, Kardol P, Knight TM, Ladouceur E, Little CJ, Roscher C, Sarneel JM, Temperton VM, van Steijn TLH, Werner CM, Wood CW, Fukami T. Priority effects transcend scales and disciplines in biology. Trends Ecol Evol 2024:S0169-5347(24)00041-7. [PMID: 38508922 DOI: 10.1016/j.tree.2024.02.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 02/12/2024] [Accepted: 02/14/2024] [Indexed: 03/22/2024]
Abstract
Although primarily studied through the lens of community ecology, phenomena consistent with priority effects appear to be widespread across many different scenarios spanning a broad range of spatial, temporal, and biological scales. However, communication between these research fields is inconsistent and has resulted in a fragmented co-citation landscape, likely due to the diversity of terms used to refer to priority effects across these fields. We review these related terms, and the biological contexts in which they are used, to facilitate greater cross-disciplinary cohesion in research on priority effects. In breaking down these semantic barriers, we aim to provide a framework to better understand the conditions and mechanisms of priority effects, and their consequences across spatial and temporal scales.
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Affiliation(s)
- J T Stroud
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA.
| | - B M Delory
- Institute of Ecology, Leuphana University Lüneburg, Lüneburg, Germany; Copernicus Institute of Sustainable Development, Utrecht University, Utrecht, The Netherlands.
| | - E M Barnes
- Thomas H. Gosnell School of Life Sciences, Rochester Institute of Technology, Rochester, NY 14623, USA
| | - J M Chase
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany; Institute of Computer Science, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - L De Meester
- Leibniz Institut für Gewässerökologie und Binnenfischerei (IGB), Müggelseedamm 310, 12587 Berlin, Germany; Institute of Biology, Freie Universität Berlin, Königin-Luise-Strasse 1-3, 14195 Berlin, Germany; Laboratory of Aquatic Ecology, Evolution, and Conservation, Katholieke Universiteit Leuven, B-3000 Leuven, Belgium
| | - J Dieskau
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany; Department of Geobotany and Botanical Garden, Martin-Luther University, Germany
| | - T N Grainger
- Department of Integrative Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - F W Halliday
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR 97331, USA
| | - P Kardol
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, 750 07 Uppsala, Sweden; Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, 90183 Umeå, Sweden
| | - T M Knight
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany; Department of Community Ecology, Helmholtz Centre for Environmental Research (UFZ), Halle (Saale), Germany; Institute of Biology, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - E Ladouceur
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany; Institute of Computer Science, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - C J Little
- School of Environmental Science, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
| | - C Roscher
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany; Department of Physiological Diversity, Helmholtz Centre for Environmental Research (UFZ), Leipzig, Germany
| | - J M Sarneel
- Department of Ecology and Environmental Science, Umea University, 901 87 Umea, Sweden
| | - V M Temperton
- Institute of Ecology, Leuphana University Lüneburg, Lüneburg, Germany
| | - T L H van Steijn
- Department of Ecology and Environmental Science, Umea University, 901 87 Umea, Sweden
| | - C M Werner
- Department of Environmental Science, Policy, and Sustainability, Southern Oregon University, Ashland, OR 97520, USA
| | - C W Wood
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - T Fukami
- Departments of Biology and Earth System Science, Stanford University, Stanford, CA 94305, USA.
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2
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Huang ZYX, Halliday FW, Becker DJ. Host functional traits as the nexus for multilevel infection patterns. Trends Ecol Evol 2023; 38:1125-1128. [PMID: 37684132 DOI: 10.1016/j.tree.2023.08.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 07/27/2023] [Accepted: 08/17/2023] [Indexed: 09/10/2023]
Abstract
Understanding pathogen transmission and infection patterns at multiple biological scales is a central issue in disease ecology and evolution. Here, we suggest that functional traits of host species readily affect infection patterns of species, communities, and landscapes, and thus serve as a linkage for multilevel studies of infectious disease.
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Affiliation(s)
- Zheng Y X Huang
- School of Life Sciences, Nanjing Normal University, 210023 Nanjing, Jiangsu, China.
| | - Fletcher W Halliday
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, 8057 Zurich, Switzerland; Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR 97331, USA
| | - Daniel J Becker
- Department of Biology, University of Oklahoma, Norman, OK 73019, USA.
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Grunberg RL, Halliday FW, Heckman RW, Joyner BN, O’Keeffe KR, Mitchell CE. Disease decreases variation in host community structure in an old-field grassland. PLoS One 2023; 18:e0293495. [PMID: 37889914 PMCID: PMC10610459 DOI: 10.1371/journal.pone.0293495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 10/13/2023] [Indexed: 10/29/2023] Open
Abstract
Disease may drive variation in host community structure by modifying the interplay of deterministic and stochastic processes that shape communities. For instance, deterministic processes like ecological selection can benefit species less impacted by disease. When communities have higher levels of disease and disease consistently selects for certain host species, this can reduce variation in host community composition. On the other hand, when host communities are less impacted by disease and selection is weaker, stochastic processes (e.g., drift, dispersal) may play a bigger role in host community structure, which can increase variation among communities. While effects of disease on host community structure have been quantified in field experiments, few have addressed the role of disease in modulating variation in structure among host communities. To address this, we conducted a field experiment spanning three years, using a tractable system: foliar fungal pathogens in an old-field grassland community dominated by the grass Lolium arundinaceum, tall fescue. We reduced foliar fungal disease burden in replicate host communities (experimental plots in intact vegetation) in three fungicide regimens that varied in the seasonal duration of fungicide treatment and included a fungicide-free control. We measured host diversity, biomass, and variation in community structure among replicate communities. Disease reduction generally decreased plant richness and increased aboveground biomass relative to communities experiencing ambient levels of disease. These changes in richness and aboveground biomass were consistent across years despite changes in structure of the plant communities over the experiment's three years. Importantly, disease reduction amplified host community variation, suggesting that disease diminished the degree to which host communities were structured by stochastic processes. These results of experimental disease reduction both highlight the potential importance of stochastic processes in plant communities and reveal the potential for disease to regulate variation in host community structure.
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Affiliation(s)
- Rita L. Grunberg
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Fletcher W. Halliday
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Robert W. Heckman
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina, United States of America
- Department of Integrative Biology, University of Texas at Austin, Austin, Texas, United States of America
| | - Brooklynn N. Joyner
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Kayleigh R. O’Keeffe
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Charles E. Mitchell
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina, United States of America
- Environment, Ecology and Energy Program, University of North Carolina, Chapel Hill, North Carolina, United States of America
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Halliday FW, Czyżewski S, Laine AL. Intraspecific trait variation and changing life-history strategies explain host community disease risk along a temperature gradient. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220019. [PMID: 36744568 PMCID: PMC9900715 DOI: 10.1098/rstb.2022.0019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Predicting how climate change will affect disease risk is complicated by the fact that changing environmental conditions can affect disease through direct and indirect effects. Species with fast-paced life-history strategies often amplify disease, and changing climate can modify life-history composition of communities thereby altering disease risk. However, individuals within a species can also respond to changing conditions with intraspecific trait variation. To test the effect of temperature, as well as inter- and intraspecifc trait variation on community disease risk, we measured foliar disease and specific leaf area (SLA; a proxy for life-history strategy) on more than 2500 host (plant) individuals in 199 communities across a 1101 m elevational gradient in southeastern Switzerland. There was no direct effect of increasing temperature on disease. Instead, increasing temperature favoured species with higher SLA, fast-paced life-history strategies. This effect was balanced by intraspecific variation in SLA: on average, host individuals expressed lower SLA with increasing temperature, and this effect was stronger among species adapted to warmer temperatures and lower latitudes. These results demonstrate how impacts of changing temperature on disease may depend on how temperature combines and interacts with host community structure while indicating that evolutionary constraints can determine how these effects are manifested under global change. This article is part of the theme issue 'Infectious disease ecology and evolution in a changing world'.
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Affiliation(s)
- Fletcher W. Halliday
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, 8057 Zurich, Switzerland
| | - Szymon Czyżewski
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, 8057 Zurich, Switzerland
| | - Anna-Liisa Laine
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, 8057 Zurich, Switzerland,Research Centre for Ecological Change, Organismal & Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, PO Box 65, Helsinki FI-00014, Finland
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Halliday FW, Jalo M, Laine AL. The effect of host community functional traits on plant disease risk varies along an elevational gradient. eLife 2021; 10:67340. [PMID: 33983120 PMCID: PMC8208817 DOI: 10.7554/elife.67340] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 05/10/2021] [Indexed: 01/17/2023] Open
Abstract
Quantifying the relative impact of environmental conditions and host community structure on disease is one of the greatest challenges of the 21st century, as both climate and biodiversity are changing at unprecedented rates. Both increasing temperature and shifting host communities toward more fast-paced life-history strategies are predicted to increase disease, yet their independent and interactive effects on disease in natural communities remain unknown. Here, we address this challenge by surveying foliar disease symptoms in 220, 0.5 m-diameter herbaceous plant communities along a 1100-m elevational gradient. We find that increasing temperature associated with lower elevation can increase disease by (1) relaxing constraints on parasite growth and reproduction, (2) determining which host species are present in a given location, and (3) strengthening the positive effect of host community pace-of-life on disease. These results provide the first field evidence, under natural conditions, that environmental gradients can alter how host community structure affects disease. Climate change is causing shifts in the ecology and biodiversity of different world regions at unprecedented rates. Global warming is also linked with changes in the risk for certain infectious diseases in humans, but also in animals and plants. There are several possible mechanisms for this. For one thing, changing weather patterns may affect how pathogens grow and reproduce. For another, the distribution ranges of animal and plant hosts of certain disease-causing pathogens are changing because of global warming. This means that the distributions of pathogens are also changing, and so is the severity of the diseases that they cause. Increasing temperatures may also influence the physiological traits that make host species suitable for pathogens. This is because the traits that allow species to survive or adapt to changes in their environment may also make them better at hosting and transmitting the pathogens that cause disease. For example, in plant communities, rising temperatures could favor species with faster growth rates, quicker reproduction and high dispersal, and these traits are often associated with more efficient spread of disease. Despite a lot of research into the effects of climate, it remains unclear how temperature, pathogen growth and reproduction, and host species’ traits and distributions combine and interact to alter infectious disease risk, especially in wild plant communities. To investigate this, Halliday, Jalo and Laine studied an area in southeast Switzerland where natural temperature and biodiversity change gradually through the region. The aim was to explore how relationships between plant biodiversity, pathogens and disease risk change with temperature, and to understand whether environmental or biological factors influence infectious disease risk more. Halliday, Jalo and Laine measured the levels of fungal diseases found in the leaves of plant communities spanning 1,100 meters of elevation, showing that higher temperatures increase disease risk both directly and indirectly. Directly, higher temperatures increased pathogen growth and reproduction, and indirectly, they influenced which plants were present and therefore able to act as disease hosts. The results also indicated that temperature can affect how the traits of plants drive the transmission rates of fungal pathogens. Important predictors of disease risk were traits relating to the growth rate of host plants, which tended to increase in areas with low elevation where the surface of the soil was warm. This study represents the first analysis, in wild plants, of how changing temperatures, the traits of shifting host species, and resident parasite populations interact to impact infectious disease risk. The insights Halliday, Jalo and Laine provided could aid in predicting how global climate change will influence infectious disease risk.
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Affiliation(s)
- Fletcher W Halliday
- Department of Evolutionary Biology and Environmental Studies, University of Zürich, Zurich, Switzerland
| | - Mikko Jalo
- Faculty of Biological and Environmental sciences, University of Helsinki, Helsinki, Finland
| | - Anna-Liisa Laine
- Department of Evolutionary Biology and Environmental Studies, University of Zürich, Zurich, Switzerland.,Faculty of Biological and Environmental sciences, University of Helsinki, Helsinki, Finland
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6
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O'Keeffe KR, Halliday FW, Jones CD, Carbone I, Mitchell CE. Parasites, niche modification and the host microbiome: A field survey of multiple parasites. Mol Ecol 2021; 30:2404-2416. [PMID: 33740826 DOI: 10.1111/mec.15892] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 02/04/2021] [Accepted: 03/15/2021] [Indexed: 01/04/2023]
Abstract
Parasites can affect and be affected by the host's microbiome, with consequences for host susceptibility, parasite transmission, and host and parasite fitness. Yet, two aspects of the relationship between parasite infection and host microbiota remain little understood: the nature of the relationship under field conditions, and how the relationship varies among parasites. To overcome these limitations, we performed a field survey of the within-leaf fungal community in a tall fescue population. We investigated how diversity and composition of the fungal microbiome associate with natural infection by fungal parasites with different feeding strategies. A parasite's feeding strategy affects both parasite requirements of the host environment and parasite impacts on the host environment. We hypothesized that parasites that more strongly modify niches available within a host will be associated with greater changes in microbiome diversity and composition. Parasites with a feeding strategy that creates necrotic tissue to extract resources (necrotrophs) may not only have different niche requirements, but also act as particularly strong niche modifiers. Barcoded amplicon sequencing of the fungal ITS region revealed that leaf segments symptomatic of necrotrophs had lower fungal diversity and distinct composition compared to segments that were asymptomatic or symptomatic of other parasites. There were no clear differences in fungal diversity or composition between leaf segments that were asymptomatic and segments symptomatic of other parasite feeding strategies. Our results motivate future experimental work to test how the relationship between the microbiome and parasite infection is impacted by parasite feeding strategy and highlight the potential importance of parasite traits.
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Affiliation(s)
- Kayleigh R O'Keeffe
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.,Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Fletcher W Halliday
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.,Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
| | - Corbin D Jones
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.,Carolina Center for Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Ignazio Carbone
- Center for Integrated Fungal Research, Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC, USA
| | - Charles E Mitchell
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.,Environment, Ecology and Energy Program, University of North Carolina, Chapel Hill, NC, USA
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7
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Halliday FW, Heckman RW, Wilfahrt PA, Mitchell CE. Eutrophication, biodiversity loss, and species invasions modify the relationship between host and parasite richness during host community assembly. Glob Chang Biol 2020; 26:4854-4867. [PMID: 32427383 DOI: 10.1111/gcb.15165] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 04/02/2020] [Accepted: 05/12/2020] [Indexed: 06/11/2023]
Abstract
Host and parasite richness are generally positively correlated, but the stability of this relationship in response to global change remains poorly understood. Rapidly changing biotic and abiotic conditions can alter host community assembly, which in turn, can alter parasite transmission. Consequently, if the relationship between host and parasite richness is sensitive to parasite transmission, then changes in host composition under various global change scenarios could strengthen or weaken the relationship between host and parasite richness. To test the hypothesis that host community assembly can alter the relationship between host and parasite richness in response to global change, we experimentally crossed host diversity (biodiversity loss) and resource supply to hosts (eutrophication), then allowed communities to assemble. As previously shown, initial host diversity and resource supply determined the trajectory of host community assembly, altering post-assembly host species richness, richness-independent host phylogenetic diversity, and colonization by exotic host species. Overall, host richness predicted parasite richness, and as predicted, this effect was moderated by exotic abundance-communities dominated by exotic species exhibited a stronger positive relationship between post-assembly host and parasite richness. Ultimately, these results suggest that, by modulating parasite transmission, community assembly can modify the relationship between host and parasite richness. These results thus provide a novel mechanism to explain how global environmental change can generate contingencies in a fundamental ecological relationship-the positive relationship between host and parasite richness.
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Affiliation(s)
- Fletcher W Halliday
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
- Department of Biology, University of North Carolina, Chapel Hill, NC, USA
| | - Robert W Heckman
- Department of Biology, University of North Carolina, Chapel Hill, NC, USA
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| | - Peter A Wilfahrt
- Environment, Ecology and Energy Program, University of North Carolina, Chapel Hill, NC, USA
- Department of Disturbance Ecology, University of Bayreuth, Bayreuth, Germany
| | - Charles E Mitchell
- Department of Biology, University of North Carolina, Chapel Hill, NC, USA
- Environment, Ecology and Energy Program, University of North Carolina, Chapel Hill, NC, USA
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8
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Halliday FW, Rohr JR, Laine AL. Biodiversity loss underlies the dilution effect of biodiversity. Ecol Lett 2020; 23:1611-1622. [PMID: 32808427 PMCID: PMC7693066 DOI: 10.1111/ele.13590] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 06/14/2020] [Accepted: 07/16/2020] [Indexed: 01/16/2023]
Abstract
The dilution effect predicts increasing biodiversity to reduce the risk of infection, but the generality of this effect remains unresolved. Because biodiversity loss generates predictable changes in host community competence, we hypothesised that biodiversity loss might drive the dilution effect. We tested this hypothesis by reanalysing four previously published meta‐analyses that came to contradictory conclusions regarding generality of the dilution effect. In the context of biodiversity loss, our analyses revealed a unifying pattern: dilution effects were inconsistently observed for natural biodiversity gradients, but were commonly observed for biodiversity gradients generated by disturbances causing losses of biodiversity. Incorporating biodiversity loss into tests of generality of the dilution effect further indicated that scale‐dependency may strengthen the dilution effect only when biodiversity gradients are driven by biodiversity loss. Together, these results help to resolve one of the most contentious issues in disease ecology: the generality of the dilution effect.
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Affiliation(s)
- Fletcher W Halliday
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, 8057, Switzerland
| | - Jason R Rohr
- Department of Biological Sciences, Eck Institute of Global Health, Environmental Change Initiative, University of Notre Dame, Notre Dame, IN, USA
| | - Anna-Liisa Laine
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, 8057, Switzerland.,Organismal & Evolutionary Biology Research Program, University of Helsinki, PO Box 65, Helsinki, FI-00014, Finland
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Greischar MA, Alexander HK, Bashey F, Bento AI, Bhattacharya A, Bushman M, Childs LM, Daversa DR, Day T, Faust CL, Gallagher ME, Gandon S, Glidden CK, Halliday FW, Hanley KA, Kamiya T, Read AF, Schwabl P, Sweeny AR, Tate AT, Thompson RN, Wale N, Wearing HJ, Yeh PJ, Mideo N. Evolutionary consequences of feedbacks between within-host competition and disease control. Evol Med Public Health 2020; 2020:30-34. [PMID: 32099654 PMCID: PMC7027713 DOI: 10.1093/emph/eoaa004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 01/21/2020] [Accepted: 01/22/2020] [Indexed: 11/14/2022]
Abstract
Lay Summary: Competition often occurs among diverse parasites within a single host, but control efforts could change its strength. We examined how the interplay between competition and control could shape the evolution of parasite traits like drug resistance and disease severity.
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Affiliation(s)
- Megan A Greischar
- Department of Ecology & Evolutionary Biology, University of Toronto, 25 Willcocks St., Toronto, ON M5S 3B2, Canada
| | - Helen K Alexander
- Department of Zoology, University of Oxford, Zoology Research and Administration Building, 11a Mansfield Road, Oxford OX1 3SZ, UK
| | - Farrah Bashey
- Department of Biology, Indiana University, 1001 E. 3rd St., Bloomington, IN 47405, USA
| | - Ana I Bento
- Odum School of Ecology and the Center for the Ecology of Infectious Diseases, University of Georgia, 140 E Green St., Athens, GA 30602, USA
| | - Amrita Bhattacharya
- Department of Biology, Indiana University, 1001 E. 3rd St., Bloomington, IN 47405, USA
| | - Mary Bushman
- Department of Biology, Emory University, Atlanta, GA 30322, USA
| | - Lauren M Childs
- Department of Mathematics, McBryde Hall, Virginia Tech, Blacksburg, VA 24061, USA
| | - David R Daversa
- Institute of Integrative Biology, University of Liverpool, Liverpool, L69 3BX, UK.,Institute of Zoology, Zoological Society of London, Regent's Park, NW1 4RY, UK
| | - Troy Day
- Departments of Mathematics & Biology, Jeffery Hall, Queen's University, Kingston, ON K7L 3N6, Canada
| | - Christina L Faust
- Institute of Biodiversity, Animal Health & Comparative Medicine, University of Glasgow, Glasgow G12 8QQ, UK
| | | | - Sylvain Gandon
- CEFE UMR 5175, CNRS - Université de Montpellier, Université Paul-Valéry Montpellier, EPHE, 1919, Route de Mende, 34293 Montpellier Cedex 5, France
| | - Caroline K Glidden
- Department of Integrative Biology, Oregon State University, 3029 Cordley Hall Corvallis, OR 97331, USA
| | - Fletcher W Halliday
- Department of Evolutionary Biology and Environmental Studies, University of Zürich, Zürich, 8057, Switzerland
| | - Kathryn A Hanley
- Department of Biology, New Mexico State University, Foster Hall, Las Cruces, NM 88003, USA
| | - Tsukushi Kamiya
- Department of Ecology & Evolutionary Biology, University of Toronto, 25 Willcocks St., Toronto, ON M5S 3B2, Canada
| | - Andrew F Read
- Center for Infectious Disease Dynamics, Huck Institutes for the Life Sciences; Departments of Biology and Entomology, Pennsylvania State University, University Park, PA 16802, USA
| | - Philipp Schwabl
- Institute of Biodiversity, Animal Health & Comparative Medicine, University of Glasgow, Glasgow G12 8QQ, UK
| | - Amy R Sweeny
- Department of Zoology, University of Oxford, Zoology Research and Administration Building, 11a Mansfield Road, Oxford OX1 3SZ, UK
| | - Ann T Tate
- Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235, USA
| | - Robin N Thompson
- Department of Zoology, University of Oxford, Zoology Research and Administration Building, 11a Mansfield Road, Oxford OX1 3SZ, UK.,Mathematical Institute, University of Oxford, Woodstock Road, Oxford OX2 6GG, UK.,Christ Church, University of Oxford, St Aldates, Oxford OX1 1DP, UK
| | - Nina Wale
- Department of Ecology & Evolutionary Biology, University of Michigan, 1105 North University Ave, Biological Sciences Building, Ann Arbor, MI 48109, USA
| | - Helen J Wearing
- Departments of Biology and Mathematics & Statistics, The University of New Mexico, Albuquerque, NM 87131, USA
| | - Pamela J Yeh
- Department of Ecology & Evolutionary Biology, University of California, Los Angeles, 621 Charles E Young Dr South, Los Angeles, CA 90095, USA
| | - Nicole Mideo
- Department of Ecology & Evolutionary Biology, University of Toronto, 25 Willcocks St., Toronto, ON M5S 3B2, Canada
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Halbritter AH, De Boeck HJ, Eycott AE, Reinsch S, Robinson DA, Vicca S, Berauer B, Christiansen CT, Estiarte M, Grünzweig JM, Gya R, Hansen K, Jentsch A, Lee H, Linder S, Marshall J, Peñuelas J, Kappel Schmidt I, Stuart‐Haëntjens E, Wilfahrt P, Vandvik V, Abrantes N, Almagro M, Althuizen IHJ, Barrio IC, te Beest M, Beier C, Beil I, Berry ZC, Birkemoe T, Bjerke JW, Blonder B, Blume‐Werry G, Bohrer G, Campos I, Cernusak LA, Chojnicki BH, Cosby BJ, Dickman LT, Djukic I, Filella I, Fuchslueger L, Gargallo‐Garriga A, Gillespie MAK, Goldsmith GR, Gough C, Halliday FW, Joar Hegland S, Hoch G, Holub P, Jaroszynska F, Johnson DM, Jones SB, Kardol P, Keizer JJ, Klem K, Konestabo HS, Kreyling J, Kröel‐Dulay G, Landhäusser SM, Larsen KS, Leblans N, Lebron I, Lehmann MM, Lembrechts JJ, Lenz A, Linstädter A, Llusià J, Macias‐Fauria M, Malyshev AV, Mänd P, Marshall M, Matheny AM, McDowell N, Meier IC, Meinzer FC, Michaletz ST, Miller ML, Muffler L, Oravec M, Ostonen I, Porcar‐Castell A, Preece C, Prentice IC, Radujković D, Ravolainen V, Ribbons R, Ruppert JC, Sack L, Sardans J, Schindlbacher A, Scoffoni C, Sigurdsson BD, Smart S, Smith SW, Soper F, Speed JDM, Sverdrup‐Thygeson A, Sydenham MAK, Taghizadeh‐Toosi A, Telford RJ, Tielbörger K, Töpper JP, Urban O, Ploeg M, Van Langenhove L, Večeřová K, Ven A, Verbruggen E, Vik U, Weigel R, Wohlgemuth T, Wood LK, Zinnert J, Zurba K. The handbook for standardized field and laboratory measurements in terrestrial climate change experiments and observational studies (ClimEx). Methods Ecol Evol 2019. [DOI: 10.1111/2041-210x.13331] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Aud H. Halbritter
- Department of Biological Sciences and Bjerknes Centre for Climate Research University of Bergen Bergen Norway
| | - Hans J. De Boeck
- Department of Biology Centre of Excellence PLECO (Plants and Ecosystems) Universiteit Antwerpen Wilrijk Belgium
| | - Amy E. Eycott
- Department of Biological Sciences University of Bergen Bergen Norway
- Faculty of Biosciences and Aquaculture Nord University Steinkjer Norway
| | - Sabine Reinsch
- Centre for Ecology & Hydrology Environment Centre Wales Bangor UK
| | | | - Sara Vicca
- Department of Biology Centre of Excellence PLECO (Plants and Ecosystems) Universiteit Antwerpen Wilrijk Belgium
| | - Bernd Berauer
- Department of Disturbance Ecology University of Bayreuth Bayreuth Germany
| | | | - Marc Estiarte
- CSIC Global Ecology Unit CREAF‐CSIC‐UAB Bellaterra Spain
- CREAF Vallès Spain
| | - José M. Grünzweig
- Institute of Plant Sciences and Genetics in Agriculture The Hebrew University of Jerusalem Rehovot Israel
| | - Ragnhild Gya
- Department of Biological Sciences and Bjerknes Centre for Climate Research University of Bergen Bergen Norway
| | - Karin Hansen
- Swedish Environmental Protection Agency Stockholm Sweden
- Swedish Environmental Research Institute IVL Stockholm Sweden
| | - Anke Jentsch
- Department of Disturbance Ecology University of Bayreuth Bayreuth Germany
| | - Hanna Lee
- NORCE Norwegian Research Centre and Bjerknes Centre for Climate Research Bergen Norway
| | - Sune Linder
- Southern Swedish Forest Research Centre Swedish University of Agricultural Sciences Alnarp Sweden
| | - John Marshall
- Department of Forest Ecology and Management Swedish University of Agricultural Sciences Umeå Sweden
| | - Josep Peñuelas
- CSIC Global Ecology Unit CREAF‐CSIC‐UAB Bellaterra Spain
- CREAF Vallès Spain
| | - Inger Kappel Schmidt
- Department of Geosciences and Natural Resource Management University of Copenhagen Frederiksberg Denmark
| | | | - Peter Wilfahrt
- Department of Disturbance Ecology University of Bayreuth Bayreuth Germany
| | - Vigdis Vandvik
- Department of Biological Sciences and Bjerknes Centre for Climate Research University of Bergen Bergen Norway
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Rohr JR, Civitello DJ, Halliday FW, Hudson PJ, Lafferty KD, Wood CL, Mordecai EA. Towards common ground in the biodiversity-disease debate. Nat Ecol Evol 2019; 4:24-33. [PMID: 31819238 PMCID: PMC7224049 DOI: 10.1038/s41559-019-1060-6] [Citation(s) in RCA: 116] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 11/13/2019] [Indexed: 01/16/2023]
Abstract
The disease ecology community has struggled to come to consensus on whether biodiversity reduces or increases infectious disease risk, a question that directly affects policy decisions for biodiversity conservation and public health. Here, we summarize the primary points of contention regarding biodiversity–disease relationships and suggest that vector-borne, generalist wildlife and zoonotic pathogens are the types of parasites most likely to be affected by changes to biodiversity. One synthesis on this topic revealed a positive correlation between biodiversity and human disease burden across countries, but as biodiversity changed over time within these countries, this correlation became weaker and more variable. Another synthesis—a meta-analysis of generally smaller-scale experimental and field studies—revealed a negative correlation between biodiversity and infectious diseases (a dilution effect) in various host taxa. These results raise the question of whether biodiversity–disease relationships are more negative at smaller spatial scales. If so, biodiversity conservation at the appropriate scales might prevent wildlife and zoonotic diseases from increasing in prevalence or becoming problematic (general proactive approaches). Further, protecting natural areas from human incursion should reduce zoonotic disease spillover. By contrast, for some infectious diseases, managing particular species or habitats and targeted biomedical approaches (targeted reactive approaches) might outperform biodiversity conservation as a tool for disease control. Importantly, biodiversity conservation and management need to be considered alongside other disease management options. These suggested guiding principles should provide common ground that can enhance scientific and policy clarity for those interested in simultaneously improving wildlife and human health. There has been intense debate as to whether biodiversity increases or reduces the risk of infectious disease. This Review is the result of researchers from both sides of the debate attempting to reach a consensus.
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Affiliation(s)
- Jason R Rohr
- Department of Biological Sciences, Eck Institute of Global Health, Environmental Change Initiative, University of Notre Dame, Notre Dame, IN, USA.
| | | | - Fletcher W Halliday
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
| | - Peter J Hudson
- Center for Infectious Disease Dynamics, Biology Department, The Pennsylvania State University, University Park, PA, USA
| | - Kevin D Lafferty
- Western Ecological Research Center, US Geological Survey, c/o Marine Science Institute, University of California, Santa Barbara, CA, USA
| | - Chelsea L Wood
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, USA
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12
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Halliday FW, Rohr JR. Measuring the shape of the biodiversity-disease relationship across systems reveals new findings and key gaps. Nat Commun 2019; 10:5032. [PMID: 31695043 PMCID: PMC6834853 DOI: 10.1038/s41467-019-13049-w] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 10/17/2019] [Indexed: 11/24/2022] Open
Abstract
Diverse host communities commonly inhibit the spread of parasites at small scales. However, the generality of this effect remains controversial. Here, we present the analysis of 205 biodiversity-disease relationships on 67 parasite species to test whether biodiversity-disease relationships are generally nonlinear, moderated by spatial scale, and sensitive to underrepresentation in the literature. Our analysis of the published literature reveals that biodiversity-disease relationships are generally hump-shaped (i.e., nonlinear) and biodiversity generally inhibits disease at local scales, but this effect weakens as spatial scale increases. Spatial scale is, however, related to study design and parasite type, highlighting the need for additional multiscale research. Few studies are unrepresentative of communities at low diversity, but missing data at low diversity from field studies could result in underreporting of amplification effects. Experiments appear to underrepresent high-diversity communities, which could result in underreporting of dilution effects. Despite context dependence, biodiversity loss at local scales appears to increase disease, suggesting that at local scales, biodiversity loss could negatively impact human and wildlife populations.
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Affiliation(s)
- Fletcher W Halliday
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland.
| | - Jason R Rohr
- Department of Biological Sciences, Eck Institute of Global Health, Environmental Change Initiative, 180 Galvin Life Science Center, University of Notre Dame, 46556, Notre Dame, IN, USA
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13
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Heckman RW, Halliday FW, Mitchell CE. A growth–defense trade-off is general across native and exotic grasses. Oecologia 2019; 191:609-620. [DOI: 10.1007/s00442-019-04507-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 09/06/2019] [Indexed: 11/27/2022]
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14
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Halliday FW, Umbanhowar J, Mitchell CE. A host immune hormone modifies parasite species interactions and epidemics: insights from a field manipulation. Proc Biol Sci 2018; 285:rspb.2018.2075. [PMID: 30404885 DOI: 10.1098/rspb.2018.2075] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 10/18/2018] [Indexed: 12/12/2022] Open
Abstract
Parasite epidemics can depend on priority effects, and parasite priority effects can result from the host immune response to prior infection. Yet we lack experimental evidence that such immune-mediated priority effects influence epidemics. To address this research gap, we manipulated key host immune hormones, then measured the consequences for within-host parasite interactions, and ultimately parasite epidemics in the field. Specifically, we applied plant immune-signalling hormones to sentinel plants, embedded into a wild host population, and tracked foliar infections caused by two common fungal parasites. Within-host individuals, priority effects were altered by the immune-signalling hormone, salicylic acid (SA). Scaling up from within-host interactions, hosts treated with SA experienced a lower prevalence of a less aggressive parasite, increased burden of infection by a more aggressive parasite, and experienced fewer co-infections. Together, these results indicate that by altering within-host priority effects, host immune hormones can drive parasite epidemics. This study therefore experimentally links host immune hormones to within-host priority effects and parasite epidemics, advancing a more mechanistic understanding of how interactions among parasites alter their epidemics.
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Affiliation(s)
- Fletcher W Halliday
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - James Umbanhowar
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA.,Curriculum for the Environment and Ecology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Charles E Mitchell
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA.,Curriculum for the Environment and Ecology, University of North Carolina, Chapel Hill, NC 27599, USA
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15
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Halliday FW, Heckman RW, Wilfahrt PA, Mitchell CE. Past is prologue: host community assembly and the risk of infectious disease over time. Ecol Lett 2018; 22:138-148. [PMID: 30403005 DOI: 10.1111/ele.13176] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 09/30/2018] [Accepted: 10/05/2018] [Indexed: 12/17/2022]
Abstract
Infectious disease risk is often influenced by host diversity, but the causes are unresolved. Changes in diversity are associated with changes in community structure, particularly during community assembly; therefore, by incorporating change over time, host community assembly may provide a framework to resolve causation. In turn, community assembly can be driven by many processes, including resource enrichment. To test the hypothesis that community assembly causally links host diversity to future disease, we experimentally manipulated host diversity and resource supply to hosts, then allowed communities to assemble for 2 years (surveyed 2012-2014). Initially, host diversity increased disease. Subsequently, host diversity did not directly alter disease. However, host diversity determined the trajectory of host community assembly, altering colonisation by exotic host species and richness-independent host phylogenetic diversity, which together reversed the initial increase in disease. Ultimately, incorporating the temporal dimension of community assembly revealed novel mechanisms linking host diversity to future disease.
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Affiliation(s)
- Fletcher W Halliday
- Department of Biology, University of North Carolina, Chapel Hill, NC, 27599, USA.,Department of Integrative Biology, University of South Florida, Tampa, FL, 33620, USA
| | - Robert W Heckman
- Department of Biology, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Peter A Wilfahrt
- Environment, Ecology and Energy Program, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Charles E Mitchell
- Department of Biology, University of North Carolina, Chapel Hill, NC, 27599, USA.,Environment, Ecology and Energy Program, University of North Carolina, Chapel Hill, NC, 27599, USA
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Halliday FW, Heckman RW, Wilfahrt PA, Mitchell CE. A multivariate test of disease risk reveals conditions leading to disease amplification. Proc Biol Sci 2018; 284:rspb.2017.1340. [PMID: 29046374 DOI: 10.1098/rspb.2017.1340] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 09/14/2017] [Indexed: 02/06/2023] Open
Abstract
Theory predicts that increasing biodiversity will dilute the risk of infectious diseases under certain conditions and will amplify disease risk under others. Yet, few empirical studies demonstrate amplification. This contrast may occur because few studies have considered the multivariate nature of disease risk, which includes richness and abundance of parasites with different transmission modes. By combining a multivariate statistical model developed for biodiversity-ecosystem-multifunctionality with an extensive field manipulation of host (plant) richness, composition and resource supply to hosts, we reveal that (i) host richness alone could not explain most changes in disease risk, and (ii) shifting host composition allowed disease amplification, depending on parasite transmission mode. Specifically, as predicted from theory, the effect of host diversity on parasite abundance differed for microbes (more density-dependent transmission) and insects (more frequency-dependent transmission). Host diversity did not influence microbial parasite abundance, but nearly doubled insect parasite abundance, and this amplification effect was attributable to variation in host composition. Parasite richness was reduced by resource addition, but only in species-rich host communities. Overall, this study demonstrates that multiple drivers, related to both host community and parasite characteristics, can influence disease risk. Furthermore, it provides a framework for evaluating multivariate disease risk in other systems.
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Affiliation(s)
- Fletcher W Halliday
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Robert W Heckman
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Peter A Wilfahrt
- Curriculum for the Environment and Ecology, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Charles E Mitchell
- Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA.,Curriculum for the Environment and Ecology, University of North Carolina, Chapel Hill, NC 27599, USA
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Halliday FW, Umbanhowar J, Mitchell CE. Interactions among symbionts operate across scales to influence parasite epidemics. Ecol Lett 2017; 20:1285-1294. [DOI: 10.1111/ele.12825] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 07/23/2017] [Indexed: 12/31/2022]
Affiliation(s)
| | - James Umbanhowar
- Department of Biology University of North Carolina Chapel Hill NC27599 USA
- Curriculum for the Environment and Ecology University of North Carolina Chapel Hill NC27599 USA
| | - Charles E. Mitchell
- Department of Biology University of North Carolina Chapel Hill NC27599 USA
- Curriculum for the Environment and Ecology University of North Carolina Chapel Hill NC27599 USA
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Heckman RW, Halliday FW, Wilfahrt PA, Mitchell CE. Effects of native diversity, soil nutrients, and natural enemies on exotic invasion in experimental plant communities. Ecology 2017; 98:1409-1418. [PMID: 28273331 DOI: 10.1002/ecy.1796] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 02/08/2017] [Accepted: 02/16/2017] [Indexed: 11/05/2022]
Abstract
Many factors can promote exotic plant success. Three of these factors-greater pressure from natural enemies on natives, increased soil nutrient supply, and low native species richness-may interact during invasions. To test for independent and interactive effects of these drivers, we planted herbaceous perennial communities at two levels of native richness (monocultures and five-species polycultures). We then factorially manipulated soil nutrient supply and access to these communities by aboveground foliar enemies (fungal pathogens and insect herbivores), and allowed natural colonization to proceed for four years. We predicted that nutrient addition would increase exotic success, while enemy exclusion and increasing native richness would reduce exotic success. Additionally, we expected that enemy exclusion would reduce the benefits of nutrient addition to exotic species most in species-poor communities, and that this effect would be weaker in species-rich communities. In total, we found no evidence that nutrient supply, enemy access, and native richness interacted to influence exotic success. Furthermore, native richness had no effect on exotic success. Instead, nutrient addition increased, and enemy exclusion decreased, exotic success independently. As predicted, enemy exclusion reduced exotic success, primarily by slowing the decline in abundance of planted native species. Together, these results demonstrate that multiple drivers of exotic success can act independently within a single system.
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Affiliation(s)
- Robert W Heckman
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina, 27599, USA
| | - Fletcher W Halliday
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina, 27599, USA
| | - Peter A Wilfahrt
- Curriculum for the Environment and Ecology, University of North Carolina, Chapel Hill, North Carolina, 27599, USA
| | - Charles E Mitchell
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina, 27599, USA.,Curriculum for the Environment and Ecology, University of North Carolina, Chapel Hill, North Carolina, 27599, USA
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Halliday FW. Educational opportunity: rural practice. Can Fam Physician 1970; 16:39-43. [PMID: 20468494 PMCID: PMC2281667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
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