51
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Guidolin AS, Cônsoli FL. Symbiont Diversity of Aphis (Toxoptera) citricidus (Hemiptera: Aphididae) as Influenced by Host Plants. MICROBIAL ECOLOGY 2017; 73:201-210. [PMID: 27872949 DOI: 10.1007/s00248-016-0892-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 10/31/2016] [Indexed: 06/06/2023]
Abstract
Aphids are well known for their association with endosymbiont bacteria. Almost all aphids harbor Buchnera aphidicola as an obligate symbiont and several other bacteria as facultative symbionts. Associations of facultative symbionts and aphids are quite variable in terms of diversity and prevalence across aphid species. Facultative symbionts can have a major impact on aphid bioecological traits. A number of factors shape the outcome of the facultative symbiont-aphid association, including aphid clone, bacterial genotype, geography, and host plant association. The effects of host plant on aphid-facultative symbiont associations are the least understood. We performed deep sequencing of the bacterial community associated with field populations of the oligophagous aphid Aphis (Toxoptera) citricidus collected from different host plants. We demonstrate that (i) A. citricidus has low symbiont diversity, (ii) symbiont diversity is affected by host plant, and (iii) host plants affect the relative abundance of the obligate symbiont Buchnera and an unknown genus of Enterobacteriaceae.
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Affiliation(s)
- Aline Sartori Guidolin
- Insect Interactions Lab., Department of Entomology and Acarology/ESALQ, University of São Paulo, Av. Pádua Dias 11, 13418-900, Piracicaba, São Paulo, Brazil
| | - Fernando Luis Cônsoli
- Insect Interactions Lab., Department of Entomology and Acarology/ESALQ, University of São Paulo, Av. Pádua Dias 11, 13418-900, Piracicaba, São Paulo, Brazil.
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52
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Heyworth ER, Ferrari J. Heat Stress Affects Facultative Symbiont-Mediated Protection from a Parasitoid Wasp. PLoS One 2016; 11:e0167180. [PMID: 27875577 PMCID: PMC5119854 DOI: 10.1371/journal.pone.0167180] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 11/09/2016] [Indexed: 01/06/2023] Open
Abstract
Many insects carry facultative bacterial symbionts, which provide benefits including resistance to natural enemies and abiotic stresses. Little is known about how these beneficial phenotypes are affected when biotic or abiotic threats occur simultaneously. The pea aphid (Acyrthosiphon pisum) can host several well-characterized symbiont species. The symbiont known as X-type can protect against both parasitoid wasps and heat stress. Here, we used three pea aphid genotypes that were naturally infected with X-type and the symbiont Spiroplasma sp. We compared aphids coinfected with these two symbionts with those cured from X-type and infected with only Spiroplasma to investigate the ability of X-type to confer benefits to the host when two threats are experienced simultaneously. Our aim is to explore how robust symbiont protection may be outside a benign laboratory environment. Aphids were subjected to heat shock either before or after attack by parasitoid wasps. Under a benign temperature regime, the aphids carrying X-type tended to be better protected from the parasitoid than those cured. When the aphids experienced a heat shock before being parasitized aphids carrying X-type were more susceptible than those cured. Regardless of infection with the symbiont, the aphids benefitted from being heat shocked after parasitization. The results demonstrate how resistance to parasitoid wasps can be strongly environment-dependent and that a beneficial phenotype conferred by a symbiont under controlled conditions in the laboratory does not necessarily equate to a consistently useful effect in natural populations.
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Affiliation(s)
| | - Julia Ferrari
- Department of Biology, University of York, York, United Kingdom
- * E-mail:
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53
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McLean AHC, Godfray HCJ. The outcome of competition between two parasitoid species is influenced by a facultative symbiont of their aphid host. Funct Ecol 2016. [DOI: 10.1111/1365-2435.12781] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Ailsa H. C. McLean
- Department of Zoology University of Oxford South Parks Road Oxford OX1 3PS UK
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54
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Hahn MA, Dheilly NM. Experimental Models to Study the Role of Microbes in Host-Parasite Interactions. Front Microbiol 2016; 7:1300. [PMID: 27602023 PMCID: PMC4993751 DOI: 10.3389/fmicb.2016.01300] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Accepted: 08/08/2016] [Indexed: 01/09/2023] Open
Abstract
Until recently, parasitic infections have been primarily studied as interactions between the parasite and the host, leaving out crucial players: microbes. The recent realization that microbes play key roles in the biology of all living organisms is not only challenging our understanding of host-parasite evolution, but it also provides new clues to develop new therapies and remediation strategies. In this paper we provide a review of promising and advanced experimental organismal systems to examine the dynamic of host-parasite-microbe interactions. We address the benefits of developing new experimental models appropriate to this new research area and identify systems that offer the best promises considering the nature of the interactions among hosts, parasites, and microbes. Based on these systems, we identify key criteria for selecting experimental models to elucidate the fundamental principles of these complex webs of interactions. It appears that no model is ideal and that complementary studies should be performed on different systems in order to understand the driving roles of microbes in host and parasite evolution.
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Affiliation(s)
- Megan A Hahn
- School of Marine and Atmospheric Sciences, Stony Brook University Stony Brook, NY, USA
| | - Nolwenn M Dheilly
- School of Marine and Atmospheric Sciences, Stony Brook University Stony Brook, NY, USA
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55
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Martinez AJ, Kim KL, Harmon JP, Oliver KM. Specificity of Multi-Modal Aphid Defenses against Two Rival Parasitoids. PLoS One 2016; 11:e0154670. [PMID: 27135743 PMCID: PMC4852904 DOI: 10.1371/journal.pone.0154670] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Accepted: 04/18/2016] [Indexed: 12/02/2022] Open
Abstract
Insects are often attacked by multiple natural enemies, imposing dynamic selective pressures for the development and maintenance of enemy-specific resistance. Pea aphids (Acyrthosiphon pisum) have emerged as models for the study of variation in resistance against natural enemies, including parasitoid wasps. Internal defenses against their most common parasitoid wasp, Aphidius ervi, are sourced through two known mechanisms– 1) endogenously encoded resistance or 2) infection with the heritable bacterial symbiont, Hamiltonella defensa. Levels of resistance can range from nearly 0–100% against A. ervi but varies based on aphid genotype and the strain of toxin-encoding bacteriophage (called APSE) carried by Hamiltonella. Previously, other parasitoid wasps were found to commonly attack this host, but North American introductions of A. ervi have apparently displaced all other parasitoids except Praon pequodorum, a related aphidiine braconid wasp, which is still found attacking this host in natural populations. To explain P. pequodorum’s persistence, multiple studies have compared direct competition between both wasps, but have not examined specificity of host defenses as an indirectly mediating factor. Using an array of experimental aphid lines, we first examined whether aphid defenses varied in effectiveness toward either wasp species. Expectedly, both types of aphid defenses were effective against A. ervi, but unexpectedly, were completely ineffective against P. pequodorum. Further examination showed that P. pequodorum wasps suffered no consistent fitness costs from developing in even highly ‘resistant’ aphids. Comparison of both wasps’ egg-larval development revealed that P. pequodorum’s eggs have thicker chorions and hatch two days later than A. ervi’s, likely explaining their differing abilities to overcome aphid defenses. Overall, our results indicate that aphids resistant to A. ervi may serve as reservoirs for P. pequodorum, hence contributing to its persistence in field populations. We find that specificity of host defenses and defensive symbiont infections, may have important roles in influencing enemy compositions by indirectly mediating the interactions and abundance of rival natural enemies.
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Affiliation(s)
- Adam J. Martinez
- Department of Entomology, University of Georgia, Athens, Georgia, United States of America
- * E-mail:
| | - Kyungsun L. Kim
- Department of Entomology, University of Georgia, Athens, Georgia, United States of America
| | - Jason P. Harmon
- Department of Entomology, North Dakota State University, Fargo, North Dakota, United States of America
| | - Kerry M. Oliver
- Department of Entomology, University of Georgia, Athens, Georgia, United States of America
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56
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Mateos M, Winter L, Winter C, Higareda-Alvear VM, Martinez-Romero E, Xie J. Independent origins of resistance or susceptibility of parasitic wasps to a defensive symbiont. Ecol Evol 2016; 6:2679-87. [PMID: 27066241 PMCID: PMC4798148 DOI: 10.1002/ece3.2085] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 02/10/2016] [Accepted: 02/22/2016] [Indexed: 01/06/2023] Open
Abstract
Insect microbe associations are diverse, widespread, and influential. Among the fitness effects of microbes on their hosts, defense against natural enemies is increasingly recognized as ubiquitous, particularly among those associations involving heritable, yet facultative, bacteria. Protective mutualisms generate complex ecological and coevolutionary dynamics that are only beginning to be elucidated. These depend in part on the degree to which symbiont‐mediated protection exhibits specificity to one or more members of the natural enemy community. Recent findings in a well‐studied defensive mutualism system (i.e., aphids, bacteria, parasitoid wasps) reveal repeated instances of evolution of susceptibility or resistance to defensive bacteria by parasitoids. This study searched for similar patterns in an emerging model system for defensive mutualisms: the interaction of Drosophila, bacteria in the genus Spiroplasma, and wasps that parasitize larval stages of Drosophila. Previous work indicated that three divergent species of parasitic wasps are strongly inhibited by the presence of Spiroplasma in three divergent species of Drosophila, including D. melanogaster. The results of this study uncovered two additional wasp species that are susceptible to Spiroplasma and two that are unaffected by Spiroplasma, implying at least two instances of loss or gain of susceptibility to Spiroplasma among larval parasitoids of Drosophila.
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Affiliation(s)
- Mariana Mateos
- Department of Wildlife and Fisheries Sciences Texas A&M University College Station Texas
| | - Lauryn Winter
- Department of Wildlife and Fisheries Sciences Texas A&M University College Station Texas
| | - Caitlyn Winter
- Department of Wildlife and Fisheries Sciences Texas A&M University College Station Texas
| | | | | | - Jialei Xie
- Department of Wildlife and Fisheries Sciences Texas A&M University College Station Texas
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57
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Donald KJ, Clarke HV, Mitchell C, Cornwell RM, Hubbard SF, Karley AJ. Protection of Pea Aphids Associated with Coinfecting Bacterial Symbionts Persists During Superparasitism by a Braconid Wasp. MICROBIAL ECOLOGY 2016; 71:1-4. [PMID: 26520831 DOI: 10.1007/s00248-015-0690-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Accepted: 10/12/2015] [Indexed: 06/05/2023]
Abstract
Bacterial endosymbionts that associate facultatively with insect herbivores can influence insect fitness and trophic interactions. The pea aphid, Acyrthosiphon pisum, can be protected from parasitism by the braconid wasp Aphidius ervi when harbouring particular symbiotic bacteria, with specific endosymbiont coinfections providing almost complete protection. However, studies often quantify aphid mummification with no control over parasitoid oviposition per aphid; thus, if mummy production fails or is low, the causes are often unclear. Here, we show that the high level of protection associated with the coinfecting endosymbionts Hamiltonella defensa and X-type is maintained even when pea aphids are superparasitised. This contrasts strongly with the protection provided by H. defensa alone, which has been shown by others to be overcome by superparasitism. By dissecting aphids exposed to two parasitoid attacks, we reveal that A. ervi deposits eggs equally freely in endosymbiont-infected and uninfected nymphs, and lack of mummification in endosymbiont-protected nymphs arises from failure of the wasp eggs to hatch or emerging larvae to develop.
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Affiliation(s)
- K J Donald
- The James Hutton Institute, Dundee, DD2 5DA, UK
| | - H V Clarke
- The James Hutton Institute, Dundee, DD2 5DA, UK
| | - C Mitchell
- The James Hutton Institute, Dundee, DD2 5DA, UK
| | | | - S F Hubbard
- School of the Environment, University of Dundee, Dundee, DD1 4HN, UK
| | - A J Karley
- The James Hutton Institute, Dundee, DD2 5DA, UK.
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58
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Polin S, Le Gallic JF, Simon JC, Tsuchida T, Outreman Y. Conditional Reduction of Predation Risk Associated with a Facultative Symbiont in an Insect. PLoS One 2015; 10:e0143728. [PMID: 26618776 PMCID: PMC4664394 DOI: 10.1371/journal.pone.0143728] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 11/08/2015] [Indexed: 11/19/2022] Open
Abstract
Symbionts are widespread among eukaryotes and their impacts on the ecology and evolution of their hosts are meaningful. Most insects harbour obligate and facultative symbiotic bacteria that can influence their phenotype. In the pea aphid Acyrthosiphon pisum, an astounding symbiotic-mediated phenotype has been recently observed: when infected with the symbiotic bacteria Rickettsiella viridis, young red aphid larvae become greener at adulthood and even darker green when co-infected with Rickettsiella viridis and Hamiltonella defensa. As body colour affects the susceptibility towards natural enemies in aphids, the influence of the colour change due to these facultative symbionts on the host survival in presence of predators was tested. Our results suggested that the Rickettsiella viridis infection may impact positively host survival by reducing predation risk. Due to results from uninfected aphids (i.e., more green ones attacked), the main assumption is that this symbiotic infection would deter the predatory ladybird feeding by reducing the profitability of their hosts rather than decreasing host detection through body colour change. Aphids co-infected with Rickettsiella viridis and Hamiltonella defensa were, however, more exposed to predation suggesting an ecological cost associated with multiple infections. The underlying mechanisms and ecological consequences of these symbiotic effects are discussed.
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Affiliation(s)
- Sarah Polin
- UMR 1349 IGEPP, Agrocampus Ouest, 35042, Rennes, France
| | | | | | - Tsutomu Tsuchida
- Frontier Research Core for Life Sciences, University of Toyama, Toyama, 930–8555, Japan
| | - Yannick Outreman
- UMR 1349 IGEPP, Agrocampus Ouest, 35042, Rennes, France
- Université Européenne de Bretagne, Rennes, France
- * E-mail:
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59
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Abstract
Ecologically important traits of insects are often affected by facultative bacterial endosymbionts. This is best studied in the pea aphid Acyrthosiphon pisum, which is frequently infected by one or more of eight facultative symbiont species. Many of these symbiont species have been shown to provide one ecological benefit, but we have little understanding of the range of effects that a single strain can have. Here, we describe the phenotypes conferred by three strains of the recently discovered bacterium known as X-type (Enterobacteriaceae), each in their original aphid genotype which also carries a Spiroplasma symbiont. All comparisons are made between aphids that are coinfected with Spiroplasma and X-type and aphids of the same genotype that harbour only Spiroplasma. We show that in all cases, infection with X-type protects aphids from the lethal fungal pathogen Pandora neoaphidis, and in two cases, resistance to the parasitoid Aphidius ervi also increases. X-type can additionally affect aphid stress responses--the presence of X-type increased reproduction after the aphids were heat-stressed. Two of the three strains of X-type are able to provide all of these benefits. Under benign conditions, the aphids tended to suffer from reduced fecundity when harbouring X-type, a mechanism that might maintain intermediate frequencies in field populations. These findings highlight that a single strain of a facultative endosymbiont has the potential to provide diverse benefits to its aphid host.
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Affiliation(s)
- E R Heyworth
- Department of Biology, University of York, York, UK
| | - J Ferrari
- Department of Biology, University of York, York, UK
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60
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Becerra JX, Venable GX, Saeidi V. Wolbachia-Free Heteropterans Do Not Produce Defensive Chemicals or Alarm Pheromones. J Chem Ecol 2015; 41:593-601. [PMID: 26070722 DOI: 10.1007/s10886-015-0596-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 02/04/2015] [Accepted: 03/06/2015] [Indexed: 01/05/2023]
Abstract
The true bugs, or heteropterans, are known for their widespread production of anti-predator chemicals and alarm pheromones in scent glands, a derived trait that constitutes one of the defining characters of the suborder Heteroptera and a potential novel trait that contributed to their diversification. We investigated whether symbiotic bacteria could be involved in the formation of these chemicals using Thasus neocalifornicus, a coreid bug that produces semiochemicals frequently found in other bugs. Using DNA phylogenetic methodology and experiments using antibiotics coupled with molecular techniques, we identified Wolbachia as the microorganism infecting the scent glands of this bug. Decreasing the level of Wobachia infection using antibiotics was correlated with a diminution of heteropteran production of defensive compounds and alarm pheromones, suggesting that this symbiotic bacterium might be implicated in the formation of chemicals.
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Affiliation(s)
- Judith X Becerra
- Department of Biosphere 2, University of Arizona, Tucson, AZ, 85721, USA,
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61
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Smith AH, Łukasik P, O'Connor MP, Lee A, Mayo G, Drott MT, Doll S, Tuttle R, Disciullo RA, Messina A, Oliver KM, Russell JA. Patterns, causes and consequences of defensive microbiome dynamics across multiple scales. Mol Ecol 2015; 24:1135-49. [DOI: 10.1111/mec.13095] [Citation(s) in RCA: 99] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Revised: 12/18/2014] [Accepted: 12/19/2014] [Indexed: 01/20/2023]
Affiliation(s)
- Andrew H. Smith
- Department of Biology; Drexel University; Philadelphia PA 19104 USA
| | - Piotr Łukasik
- Department of Biology; Drexel University; Philadelphia PA 19104 USA
| | | | - Amanda Lee
- Department of Biology; Drexel University; Philadelphia PA 19104 USA
| | - Garrett Mayo
- Department of Biology; Drexel University; Philadelphia PA 19104 USA
| | - Milton T. Drott
- Department of Biology; Drexel University; Philadelphia PA 19104 USA
| | - Steven Doll
- Department of Biology; Drexel University; Philadelphia PA 19104 USA
| | - Robert Tuttle
- Department of Biology; Drexel University; Philadelphia PA 19104 USA
| | | | - Andrea Messina
- Department of Biology; Drexel University; Philadelphia PA 19104 USA
| | - Kerry M. Oliver
- Department of Entomology; University of Georgia; Athens GA 30602 USA
| | - Jacob A. Russell
- Department of Biology; Drexel University; Philadelphia PA 19104 USA
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62
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Hoddle MS, Warner K, Steggall J, Jetter KM. Classical Biological Control of Invasive Legacy Crop Pests: New Technologies Offer Opportunities to Revisit Old Pest Problems in Perennial Tree Crops. INSECTS 2014; 6:13-37. [PMID: 26463063 PMCID: PMC4553525 DOI: 10.3390/insects6010013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 12/13/2014] [Indexed: 11/24/2022]
Abstract
Advances in scientific disciplines that support classical biological control have provided "new tools" that could have important applications for biocontrol programs for some long-established invasive arthropod pests. We suggest that these previously unavailable tools should be used in biological control programs targeting "legacy pests", even if they have been targets of previously unsuccessful biocontrol projects. Examples of "new tools" include molecular analyses to verify species identities and likely geographic area of origin, climate matching and ecological niche modeling, preservation of natural enemy genetic diversity in quarantine, the use of theory from invasion biology to maximize establishment likelihoods for natural enemies, and improved understanding of the interactions between natural enemy and target pest microbiomes. This review suggests that opportunities exist for revisiting old pest problems and funding research programs using "new tools" for developing biological control programs for "legacy pests" could provide permanent suppression of some seemingly intractable pest problems. As a case study, we use citricola scale, Coccus pseudomagnoliarum, an invasive legacy pest of California citrus, to demonstrate the potential of new tools to support a new classical biological control program targeting this insect.
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Affiliation(s)
- Mark S Hoddle
- Department of Entomology, University of California, Riverside, CA 92521, USA.
| | - Keith Warner
- Center for Science, Technology, and Society, Santa Clara University, CA 95053, USA.
| | - John Steggall
- California Department of Food and Agriculture, Sacramento, CA 95814, USA.
| | - Karen M Jetter
- UC Agricultural Issues Center, University of California, Davis, CA 95616, USA.
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63
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McLean AHC, Godfray HCJ. An experimental test of whether the defensive phenotype of an aphid facultative symbiont can respond to selection within a host lineage. PLoS One 2014; 9:e111601. [PMID: 25396733 PMCID: PMC4232250 DOI: 10.1371/journal.pone.0111601] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 10/06/2014] [Indexed: 12/22/2022] Open
Abstract
An experiment was conducted to test whether parasitoid resistance within a single clonal line of pea aphid (Acyrthosiphon pisum) might increase after exposure to the parasitoid wasp Aphidius ervi. Any change in resistance was expected to occur through an increase in the density of protective symbiotic bacteria rather than genetic change within the aphid or the bacterial symbiont. Six aphid lineages were exposed to high parasitoid attack rates over nine generations, each line being propagated from individuals that had survived attack; a further six lineages were maintained without parasitoids as a control. At the end of the experiment the strength of resistance of aphids from treatment and control lines were compared. No differences in resistance were found.
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Affiliation(s)
- Ailsa H. C. McLean
- Department of Zoology, University of Oxford, Oxford, United Kingdom
- * E-mail:
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64
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Oliver KM, Martinez AJ. How resident microbes modulate ecologically-important traits of insects. CURRENT OPINION IN INSECT SCIENCE 2014; 4:1-7. [PMID: 28043402 DOI: 10.1016/j.cois.2014.08.001] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 07/30/2014] [Accepted: 08/05/2014] [Indexed: 05/20/2023]
Abstract
The microbiota inhabiting insects influence a wide range of ecologically-important traits. In addition to their better-known roles in nutrient provisioning and degrading plant polymers, there is emerging evidence that microorganisms also aid herbivores in countering plant defenses. The latter can be mediated by enzymes that degrade plant allelochemicals or via the modulation of plant signaling pathways. Symbionts are also increasingly recognized to protect insects from attack by a wide range of natural enemies. Underlying mechanisms are poorly understood, but some microbes produce antimicrobials or toxins, while others modulate insect immune responses. Ecologically-relevant symbioses can exhibit dynamic variation in strength and specificity of conferred phenotypes, transfer key traits among unrelated insects, and have effects that extend to interacting players and beyond.
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Affiliation(s)
- Kerry M Oliver
- Department of Entomology, University of Georgia, Athens, GA 30602, USA.
| | - Adam J Martinez
- Department of Entomology, University of Georgia, Athens, GA 30602, USA
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65
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Duron O. Arsenophonus insect symbionts are commonly infected with APSE, a bacteriophage involved in protective symbiosis. FEMS Microbiol Ecol 2014; 90:184-94. [PMID: 25041857 DOI: 10.1111/1574-6941.12381] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 07/08/2014] [Accepted: 07/09/2014] [Indexed: 11/29/2022] Open
Abstract
Insects commonly have intimate associations with maternally inherited bacterial symbionts. While many inherited symbionts are not essential for host survival, they often act as conditional mutualists, conferring protection against certain environmental stresses. The defensive symbiont Hamiltonella defensa which protects aphids against attacks by parasitoid wasps is one of these conditional mutualists. The protection afforded by Hamiltonella depends on the presence of a lysogenic bacteriophage, called APSE, encoding homologs of toxins that are suspected to target wasp cells. In this study, an important diversity of APSE variants is reported from another heritable symbiont, Arsenophonus, which is exceptionally widespread in insects. APSE was found in association with two-thirds of the Arsenophonus strains examined and from a variety of insect groups such as aphids, white flies, parasitoid wasps, triatomine bugs, louse flies, and bat flies. No APSE was, however, found from Arsenophonus relatives such as the recently described Aschnera chinzeii and ALO-3 endosymbionts. Phylogenetic investigations revealed that APSE has a long evolutionary history in heritable symbionts, being secondarily acquired by Hamiltonella through lateral transfer from Arsenophonus. Overall, this highlights the role of lateral transfer as a major evolutionary process shaping the emergence of defensive symbiosis in heritable bacteria.
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Affiliation(s)
- Olivier Duron
- Institut des Sciences de l'Evolution, CNRS-UM2 (UMR5554), Montpellier Cedex 05, France
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66
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67
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Martinez AJ, Ritter SG, Doremus MR, Russell JA, Oliver KM. Aphid-encoded variability in susceptibility to a parasitoid. BMC Evol Biol 2014; 14:127. [PMID: 24916045 PMCID: PMC4057601 DOI: 10.1186/1471-2148-14-127] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Accepted: 05/27/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Many animals exhibit variation in resistance to specific natural enemies. Such variation may be encoded in their genomes or derived from infection with protective symbionts. The pea aphid, Acyrthosiphon pisum, for example, exhibits tremendous variation in susceptibility to a common natural enemy, the parasitic wasp Aphidius ervi. Pea aphids are often infected with the heritable bacterial symbiont, Hamiltonella defensa, which confers partial to complete resistance against this parasitoid depending on bacterial strain and associated bacteriophages. That previous studies found that pea aphids without H. defensa (or other symbionts) were generally susceptible to parasitism, together with observations of a limited encapsulation response, suggested that pea aphids largely rely on infection with H. defensa for protection against parasitoids. However, the limited number of uninfected clones previously examined, and our recent report of two symbiont-free resistant clones, led us to explicitly examine aphid-encoded variability in resistance to parasitoids. RESULTS After rigorous screening for known and unknown symbionts, and microsatellite genotyping to confirm clonal identity, we conducted parasitism assays using fifteen clonal pea aphid lines. We recovered significant variability in aphid-encoded resistance, with variation levels comparable to that contributed by H. defensa. Because resistance can be costly, we also measured aphid longevity and cumulative fecundity of the most and least resistant aphid lines under permissive conditions, but found no trade-offs between higher resistance and these fitness parameters. CONCLUSIONS These results indicate that pea aphid resistance to A. ervi is more complex than previously appreciated, and that aphids employ multiple tactics to aid in their defense. While we did not detect a tradeoff, these may become apparent under stressful conditions or when resistant and susceptible aphids are in direct competition. Understanding sources and amounts of variation in resistance to natural enemies is necessary to understand the ecological and evolutionary dynamics of antagonistic interactions, such as the potential for coevolution, but also for the successful management of pest populations through biological control.
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Affiliation(s)
- Adam J Martinez
- Department of Entomology, University of Georgia, Athens GA 30602, USA
| | - Shannon G Ritter
- Department of Entomology, University of Georgia, Athens GA 30602, USA
| | - Matthew R Doremus
- Department of Entomology, University of Georgia, Athens GA 30602, USA
| | - Jacob A Russell
- Department of Biology, Drexel University, Philadelphia PA 19104, USA
| | - Kerry M Oliver
- Department of Entomology, University of Georgia, Athens GA 30602, USA
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Vorburger C. The evolutionary ecology of symbiont-conferred resistance to parasitoids in aphids. INSECT SCIENCE 2014; 21:251-264. [PMID: 24167113 DOI: 10.1111/1744-7917.12067] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/21/2013] [Indexed: 06/02/2023]
Abstract
Aphids may harbor a wide variety of facultative bacterial endosymbionts. These symbionts are transmitted maternally with high fidelity and they show horizontal transmission as well, albeit at rates too low to enable infectious spread. Such symbionts need to provide a net fitness benefit to their hosts to persist and spread. Several symbionts have achieved this by evolving the ability to protect their hosts against parasitoids. Reviewing empirical work and some models, I explore the evolutionary ecology of symbiont-conferred resistance to parasitoids in order to understand how defensive symbiont frequencies are maintained at the intermediate levels observed in aphid populations. I further show that defensive symbionts alter the reciprocal selection between aphids and parasitoids by augmenting the heritable variation for resistance, by increasing the genetic specificity of the host-parasitoid interaction, and by inducing environment-dependent trade-offs. These effects are conducive to very dynamic, symbiont-mediated coevolution that is driven by frequency-dependent selection. Finally I argue that defensive symbionts represent a problem for biological control of pest aphids, and I propose to mitigate this problem by exploiting the parasitoids' demonstrated ability to rapidly evolve counteradaptations to symbiont-conferred resistance.
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Affiliation(s)
- Christoph Vorburger
- Institute of Integrative Biology, ETH Zürich, Universitätstrasse 16, 8092 Zürich; EAWAG, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, 8600 Dübendorf, Switzerland
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69
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Rouchet R, Vorburger C. EXPERIMENTAL EVOLUTION OF PARASITOID INFECTIVITY ON SYMBIONT-PROTECTED HOSTS LEADS TO THE EMERGENCE OF GENOTYPE SPECIFICITY. Evolution 2014; 68:1607-16. [DOI: 10.1111/evo.12377] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Accepted: 01/28/2014] [Indexed: 01/02/2023]
Affiliation(s)
- Romain Rouchet
- Institute of Integrative Biology; ETH Zürich; Zürich Switzerland
- EAWAG; Swiss Federal Institute of Aquatic Science and Technology; Dübendorf Switzerland
| | - Christoph Vorburger
- Institute of Integrative Biology; ETH Zürich; Zürich Switzerland
- EAWAG; Swiss Federal Institute of Aquatic Science and Technology; Dübendorf Switzerland
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70
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Aphid facultative symbionts reduce survival of the predatory lady beetle Hippodamia convergens. BMC Ecol 2014; 14:5. [PMID: 24555501 PMCID: PMC3936903 DOI: 10.1186/1472-6785-14-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Accepted: 02/04/2014] [Indexed: 01/19/2023] Open
Abstract
Background Non-essential facultative endosymbionts can provide their hosts with protection from parasites, pathogens, and predators. For example, two facultative bacterial symbionts of the pea aphid (Acyrthosiphon pisum), Serratia symbiotica and Hamiltonella defensa, protect their hosts from parasitism by two species of parasitoid wasp. Previous studies have not explored whether facultative symbionts also play a defensive role against predation in this system. We tested whether feeding on aphids harboring different facultative symbionts affected the fitness of an aphid predator, the lady beetle Hippodamia convergens. Results While these aphid faculative symbionts did not deter lady beetle feeding, they did decrease survival of lady beetle larvae. Lady beetle larvae fed a diet of aphids with facultative symbionts had significantly reduced survival from egg hatching to pupation and therefore had reduced survival to adult emergence. Additionally, lady beetle adults fed aphids with facultative symbionts were significantly heavier than those fed facultative symbiont-free aphids, though development time was not significantly different. Conclusions Aphids reproduce clonally and are often found in large groups. Thus, aphid symbionts, by reducing the fitness of the aphid predator H. convergens, may indirectly defend their hosts’ clonal descendants against predation. These findings highlight the often far-reaching effects that symbionts can have in ecological systems.
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71
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de Oliveira CF, Long EY, Finke DL. A negative effect of a pathogen on its vector? A plant pathogen increases the vulnerability of its vector to attack by natural enemies. Oecologia 2013; 174:1169-77. [DOI: 10.1007/s00442-013-2854-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 11/27/2013] [Indexed: 11/25/2022]
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72
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Xie J, Butler S, Sanchez G, Mateos M. Male killing Spiroplasma protects Drosophila melanogaster against two parasitoid wasps. Heredity (Edinb) 2013; 112:399-408. [PMID: 24281548 DOI: 10.1038/hdy.2013.118] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Revised: 10/01/2013] [Accepted: 10/02/2013] [Indexed: 11/09/2022] Open
Abstract
Maternally transmitted associations between endosymbiotic bacteria and insects are diverse and widespread in nature. Owing to imperfect vertical transmission, many heritable microbes have evolved compensational mechanisms to enhance their persistence in host lineages, such as manipulating host reproduction and conferring fitness benefits to host. Symbiont-mediated defense against natural enemies of hosts is increasingly recognized as an important mechanism by which endosymbionts enhance host fitness. Members of the genus Spiroplasma associated with distantly related Drosophila hosts are known to engage in either reproductive parasitism (i.e., male killing) or defense against natural enemies (the parasitic wasp Leptopilina heterotoma and a nematode). A male-killing strain of Spiroplasma (strain Melanogaster Sex Ratio Organism (MSRO)) co-occurs with Wolbachia (strain wMel) in certain wild populations of the model organism Drosophila melanogaster. We examined the effects of Spiroplasma MSRO and Wolbachia wMel on Drosophila survival against parasitism by two common wasps, Leptopilina heterotoma and Leptopilina boulardi, that differ in their host ranges and host evasion strategies. The results indicate that Spiroplasma MSRO prevents successful development of both wasps, and confers a small, albeit significant, increase in larva-to-adult survival of flies subjected to wasp attacks. We modeled the conditions under which defense can contribute to Spiroplasma persistence. Wolbachia also confers a weak, but significant, survival advantage to flies attacked by L. heterotoma. The host protective effects exhibited by Spiroplasma and Wolbachia are additive and may provide the conditions for such cotransmitted symbionts to become mutualists. Occurrence of Spiroplasma-mediated protection against distinct parasitoids in divergent Drosophila hosts suggests a general protection mechanism.
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Affiliation(s)
- J Xie
- Department of Wildlife and Fisheries Sciences, Texas A&M University, College Station, TX, USA
| | - S Butler
- Department of Wildlife and Fisheries Sciences, Texas A&M University, College Station, TX, USA
| | - G Sanchez
- Department of Wildlife and Fisheries Sciences, Texas A&M University, College Station, TX, USA
| | - M Mateos
- Department of Wildlife and Fisheries Sciences, Texas A&M University, College Station, TX, USA
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73
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Effects of heat shock on resistance to parasitoids and on life history traits in an aphid/endosymbiont system. PLoS One 2013; 8:e75966. [PMID: 24143175 PMCID: PMC3797046 DOI: 10.1371/journal.pone.0075966] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2013] [Accepted: 08/17/2013] [Indexed: 11/25/2022] Open
Abstract
Temperature variation is an important factor determining the outcomes of interspecific interactions, including those involving hosts and parasites. This can apply to variation in average temperature or to relatively short but intense bouts of extreme temperature. We investigated the effect of heat shock on the ability of aphids (Aphis fabae) harbouring protective facultative endosymbionts (Hamiltonella defensa) to resist parasitism by Hymenopteran parasitoids (Lysiphlebus fabarum). Furthermore, we investigated whether heat shocks can modify previously observed genotype-by-genotype (G x G) interactions between different endosymbiont isolates and parasitoid genotypes. Lines of genetically identical aphids possessing different isolates of H. defensa were exposed to one of two heat shock regimes (35°C and 39°C) or to a control temperature (20°C) before exposure to three different asexual lines of the parasitoids. We observed strong G x G interactions on parasitism rates, reflecting the known genetic specificity of symbiont-conferred resistance, and we observed a significant G x G x E interaction induced by heat shocks. However, this three-way interaction was mainly driven by the more extreme heat shock (39°C), which had devastating effects on aphid lifespan and reproduction. Restricting the analysis to the more realistic heat shock of 35°C, the G x G x E interaction was weaker (albeit still significant), and it did not lead to any reversals of the aphid lines' susceptibility rankings to different parasitoids. Thus, under conditions feasibly encountered in the field, the relative fitness of different parasitoid genotypes on hosts protected by particular symbiont strains remains mostly uncomplicated by heat stress, which should simplify biological control programs dealing with this system.
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74
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Oliver KM, Smith AH, Russell JA. Defensive symbiosis in the real world - advancing ecological studies of heritable, protective bacteria in aphids and beyond. Funct Ecol 2013. [DOI: 10.1111/1365-2435.12133] [Citation(s) in RCA: 255] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Kerry M. Oliver
- Department of Entomology; University of Georgia; Athens GA 30602 USA
| | - Andrew H. Smith
- Department of Biology; Drexel University; Philadelphia PA 19104 USA
| | - Jacob A. Russell
- Department of Biology; Drexel University; Philadelphia PA 19104 USA
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75
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The diversity and fitness effects of infection with facultative endosymbionts in the grain aphid, Sitobion avenae. Oecologia 2013; 173:985-96. [DOI: 10.1007/s00442-013-2660-5] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Accepted: 04/11/2013] [Indexed: 12/31/2022]
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76
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Andrew RL, Bernatchez L, Bonin A, Buerkle CA, Carstens BC, Emerson BC, Garant D, Giraud T, Kane NC, Rogers SM, Slate J, Smith H, Sork VL, Stone GN, Vines TH, Waits L, Widmer A, Rieseberg LH. A road map for molecular ecology. Mol Ecol 2013; 22:2605-26. [DOI: 10.1111/mec.12319] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Accepted: 03/16/2013] [Indexed: 12/18/2022]
Affiliation(s)
- Rose L. Andrew
- Department of Botany; University of British Columbia; 3529-6270 University Blvd Vancouver BC V6T 1Z4 Canada
| | - Louis Bernatchez
- DInstitut de Biologie Intégrative et des Systémes; Département de Biologie; 1030, Avenue de la Médecine Université Laval; Québec QC G1V 0A6 Canada
| | - Aurélie Bonin
- Laboratoire d'Ecologie Alpine; CNRS UMR 5553 Université Joseph Fourier; BP 53, 38041 Grenoble Cedex 9 France
| | - C. Alex. Buerkle
- Department of Botany; University of Wyoming; 1000 E. University Ave. Laramie WY 82071 USA
| | - Bryan C. Carstens
- Department of Evolution, Ecology and Organismal Biology; 318 W. 12th Ave. The Ohio State University; Columbus OH 43210 USA
| | - Brent C. Emerson
- Island Ecology and Evolution Research Group; Instituto de Productos Naturales y Agrobiología (IPNA-CSIC) C/Astrofísico Francisco Sánchez 3 La Laguna Tenerife; Canary Islands 38206 Spain
| | - Dany Garant
- Département de Biologie; Université de Sherbrooke; Sherbrooke QC J1K 2R1 Canada
| | - Tatiana Giraud
- Laboratoire Ecologie, Systématique et Evolution; UMR 8079 CNRS-UPS-AgroParisTech, Bâtiment 360 Univ. Paris Sud; 91405 Orsay cedex France
| | - Nolan C. Kane
- Department of Botany; University of British Columbia; 3529-6270 University Blvd Vancouver BC V6T 1Z4 Canada
| | - Sean M. Rogers
- Department of Biological Sciences; University of Calgary; 2500 University Drive N.W., Calgary AB T2N 1N4 Canada
| | - Jon Slate
- Department of Animal and Plant Sciences; University of Sheffield; Sheffield S10 2TN UK
| | - Harry Smith
- 79 Melton Road Burton-on-the-Wolds Loughborough LE12 5TQ UK
| | - Victoria L. Sork
- Department of Ecology and Evolutionary Biology; University of California Los Angeles; 4139 Terasaki Life Sciences Building, 610 Charles E. Young Drive East Los Angeles CA 90095 USA
| | - Graham N. Stone
- Institute of Evolutionary Biology; University of Edinburgh; The King's Buildings, West Mains Road, Edinburgh EH9 3JT UK
| | - Timothy H. Vines
- Molecular Ecology Editorial Office; 6270 University Blvd Vancouver BC V6T 1Z4 Canada
| | - Lisette Waits
- Department of Fish and Wildlife Sciences; University of Idaho; 875 Perimeter Drive MS 1136 Moscow ID 83844 USA
| | - Alex Widmer
- ETH Zurich; Institute of Integrative Biology; Universitätstrasse 16 Zurich 8092 Switzerland
| | - Loren H. Rieseberg
- Department of Botany; University of British Columbia; 3529-6270 University Blvd Vancouver BC V6T 1Z4 Canada
- Department of Biology; Indiana University; 1001 E. 3 St., Bloomington IN 47405 USA
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Bilodeau E, Guay JF, Turgeon J, Cloutier C. Survival to parasitoids in an insect hosting defensive symbionts: a multivariate approach to polymorphic traits affecting host use by its natural enemy. PLoS One 2013; 8:e60708. [PMID: 23565269 PMCID: PMC3614562 DOI: 10.1371/journal.pone.0060708] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Accepted: 03/01/2013] [Indexed: 11/18/2022] Open
Abstract
Insect parasitoids and their insect hosts represent a wide range of parasitic trophic relations that can be used to understand the evolution of biotic diversity on earth. Testing theories of coevolution between hosts and parasites is based on factors directly involved in host susceptibility and parasitoid virulence. We used controlled encounters with potential hosts of the Aphidius ervi wasp to elucidate behavioral and other phenotypic traits of host Acyrthosiphon pisum that most contribute to success or failure of parasitism. The host aphid is at an advanced stage of specialization on different crop plants, and exhibits intra-population polymorphism for traits of parasitoid avoidance and resistance based on clonal variation of color morph and anti-parasitoid bacterial symbionts. Randomly selected aphid clones from alfalfa and clover were matched in 5 minute encounters with wasps of two parasitoid lineages deriving from hosts of each plant biotype in a replicated transplant experimental design. In addition to crop plant affiliation (alfalfa, clover), aphid clones were characterized for color morph (green, pink), Hamiltonella defensa and Regiella insecticola symbionts, and frequently used behaviors in encounters with A. ervi wasps. A total of 12 explanatory variables were examined using redundancy analysis (RDA) to predict host survival or failure to A. ervi parasitism. Aphid color was the best univariate predictor, but was poorly predictive in the RDA model. In contrast, aphid host plant and symbionts were not significant univariate predictors, but significant predictors in the multivariate model. Aphid susceptibility to wasp acceptance as reflected in host attacks and oviposition clearly differed from its suitability to parasitism and progeny development. Parasitoid progeny were three times more likely to survive on clover than alfalfa host aphids, which was compensated by behaviorally adjusting eggs invested per host. Strong variation of the predictive power of intrinsic (body color) and extrinsic traits (symbionts, host plant), indicate that host variables considered as key predictors of outcomes strongly interact and cannot be considered in isolation.
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Affiliation(s)
- Emilie Bilodeau
- Département de Biologie, Université Laval, Québec, Québec, Canada
| | | | - Julie Turgeon
- Département de Biologie, Université Laval, Québec, Québec, Canada
| | - Conrad Cloutier
- Département de Biologie, Université Laval, Québec, Québec, Canada
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Vorburger C, Ganesanandamoorthy P, Kwiatkowski M. Comparing constitutive and induced costs of symbiont-conferred resistance to parasitoids in aphids. Ecol Evol 2013; 3:706-13. [PMID: 23533102 PMCID: PMC3605857 DOI: 10.1002/ece3.491] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 12/28/2012] [Accepted: 01/08/2013] [Indexed: 12/02/2022] Open
Abstract
Host defenses against parasites do not come for free. The evolution of increased resistance can be constrained by constitutive costs associated with possessing defense mechanisms, and by induced costs of deploying them. These two types of costs are typically considered with respect to resistance as a genetically determined trait, but they may also apply to resistance provided by ‘helpers’ such as bacterial endosymbionts. We investigated the costs of symbiont-conferred resistance in the black bean aphid, Aphis fabae (Scopoli), which receives strong protection against the parasitoid Lysiphlebus fabarum from the defensive endosymbiont Hamiltonella defensa. Aphids infected with H. defensa were almost ten times more resistant to L. fabarum than genetically identical aphids without this symbiont, but in the absence of parasitoids, they had strongly reduced lifespans, resulting in lower lifetime reproduction. This is evidence for a substantial constitutive cost of harboring H. defensa. We did not observe any induced cost of symbiont-conferred resistance. On the contrary, symbiont-protected aphids that resisted a parasitoid attack enjoyed increased longevity and lifetime reproduction compared with unattacked controls, whereas unprotected aphids suffered a reduction of longevity and reproduction after resisting an attack. This surprising result suggests that by focusing exclusively on the protection, we might underestimate the selective advantage of infection with H. defensa in the presence of parasitoids.
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Affiliation(s)
- Christoph Vorburger
- Institute of Integrative Biology, ETH Zürich Universitätstrasse 16, 8092, Zürich, Switzerland ; EAWAG, Swiss Federal Institute of Aquatic Science and Technology Überlandstrasse 133, 8600, Dübendorf, Switzerland
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Ezenwa VO, Gerardo NM, Inouye DW, Medina M, Xavier JB. Microbiology. Animal behavior and the microbiome. Science 2012; 338:198-9. [PMID: 23066064 DOI: 10.1126/science.1227412] [Citation(s) in RCA: 319] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Vanessa O Ezenwa
- Odum School of Ecology and Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
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