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Asakura H, Futamura R, Moriyama S, Iida S, Araki K, Ayumi M, Kumikawa S, Matsuoka Y, Takahashi T, Uchida J, Kishida O, Sato T. Two distinct host-parasite associations mediate seasonal ecosystem linkages. Biol Lett 2024; 20:20240065. [PMID: 39016002 PMCID: PMC11252854 DOI: 10.1098/rsbl.2024.0065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 04/16/2024] [Accepted: 06/05/2024] [Indexed: 07/18/2024] Open
Abstract
Nematomorph parasites manipulate terrestrial arthropods to enter streams where the parasites reproduce. These manipulated arthropods become a substantial prey subsidy for stream salmonids, causing cross-ecosystem energy flow. Diverse nematomorph-arthropod associations underlie the energy flow, but it remains unknown whether they can mediate the magnitude and temporal attributes of the energy flow. Here, we investigated whether distinct phylogenetic groups of nematomorphs manipulate different arthropod hosts and mediate seasonal prey subsidy for stream salmonids. The results of our molecular-based diagnoses show that Gordionus and Gordius nematomorphs infected ground beetle and orthopteran hosts, respectively. The presumable ground beetle hosts subsidized salmonid individuals in spring, whereas the presumable orthopteran hosts did so in autumn. Maintaining the two distinct nematomorph-arthropod associations thus resulted in the parasite-mediated prey subsidy in both spring and autumn in the study streams. Manipulative parasites are common, and often associated with a range of host lineages, suggesting that similar effects of phylogenetic variation in host-parasite associations on energy flow might be widespread in nature.
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Affiliation(s)
- Hinako Asakura
- Department of Zoology, Graduate School of Science, Kyoto University, Kyoto, Japan
| | - Ryo Futamura
- Graduate School of Environmental Sciences, Hokkaido University, Hokkaido, Japan
- Department of Fish Biology, Fisheries and Aquaculture, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany
| | - Senri Moriyama
- Graduate School of Environmental Sciences, Hokkaido University, Hokkaido, Japan
| | - Satoko Iida
- Center for Ecological Research, Kyoto University, Kyoto, Japan
| | - Koume Araki
- Tomakomai Experimental Forest, Field Science Center for Northern Biosphere, Hokkaido University, Hokkaido, Japan
| | - Masato Ayumi
- Tomakomai Experimental Forest, Field Science Center for Northern Biosphere, Hokkaido University, Hokkaido, Japan
| | - Shoji Kumikawa
- Tomakomai Experimental Forest, Field Science Center for Northern Biosphere, Hokkaido University, Hokkaido, Japan
| | - Yuichi Matsuoka
- Tomakomai Experimental Forest, Field Science Center for Northern Biosphere, Hokkaido University, Hokkaido, Japan
| | - Taro Takahashi
- Tomakomai Experimental Forest, Field Science Center for Northern Biosphere, Hokkaido University, Hokkaido, Japan
| | - Jiro Uchida
- Tomakomai Experimental Forest, Field Science Center for Northern Biosphere, Hokkaido University, Hokkaido, Japan
| | - Osamu Kishida
- Wakayama Experimental Forest, Field Science Center for Northern Biosphere, Hokkaido University, Hokkaido, Japan
| | - Takuya Sato
- Center for Ecological Research, Kyoto University, Kyoto, Japan
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Achiorno C, Minardi G. Glyphosate-environmental variables interaction: How does it affect the parasite Chordodes nobilii? CHEMOSPHERE 2024; 358:142219. [PMID: 38704040 DOI: 10.1016/j.chemosphere.2024.142219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 04/27/2024] [Accepted: 04/30/2024] [Indexed: 05/06/2024]
Abstract
The worldwide used herbicide Glyphosate can interact with environmental variables, but there is limited information on the influence of environmental stressors on its toxicity. Environmental changes could modify glyphosate effects on non-target organisms, including parasites such as gordiids. The freshwater microscopic larvae of the gordiid Chordodes nobilii are sensitive to several pollutants and environmental variables, but their combined effect has not been evaluated yet. The aim of this study was to evaluate the impact of temperature, pH and exposure time on the toxicity of Glyphosate to C. nobilii larvae. A protocol was followed to evaluate the infectivity of larvae treated with factorial combinations of concentration (0 and 0.067 mg/L), exposure time (24 and 48 h), temperature (18, 23 and 28 °C), and pH (7, 8 and 9). The reference values were 23 °C, pH 8 and 48 h. The interaction effect on the infectivity of gordiid larvae was assessed post-exposure using Aedes aegyptii larvae as host. Results were evaluated using GLMM, which does not require data transformation. The modeling results revealed three highly significant triple interactions. Glyphosate toxicity varied depending on the combination of variables, with a decrease being observed after 24 h-exposure at pH 7 and 23 °C. Glyphosate and 28 °C combination led to slightly reduced infectivity compared to temperature alone. This study is the first to report the combined effects of glyphosate, temperature, pH and time on a freshwater animal. It demonstrates that a specific combination of factors determines the effect of glyphosate on a non-target organism. The potential use of C. nobilli as a bioindicator is discussed. In the context of global warming and considering that the behavioral manipulation of terrestrial hosts by gordiids can shape community structure and the energy flow through food webs, our results raise concerns about possible negative effects of climate change on host-parasite dynamics.
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Affiliation(s)
- Cecilia Achiorno
- Centro de Estudios Parasitológicos y de Vectores (CEPAVE), Universidad Nacional de La Plata (CCT La Plata CONICET-UNLP), La Plata, 1900, Buenos Aires, Argentina.
| | - Graciela Minardi
- Centro de Estudios Parasitológicos y de Vectores (CEPAVE), Universidad Nacional de La Plata (CCT La Plata CONICET-UNLP), La Plata, 1900, Buenos Aires, Argentina
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Tani S, Tettey PA, Maruta R, Kodama A, Saito H, Kawai K. Host range differences between two species of freshwater horsehair worm (Nematomorpha: Chordiidae) Chordodes japonensis and C. formosanus in Japan. Parasitol Int 2024; 99:102847. [PMID: 38142815 DOI: 10.1016/j.parint.2023.102847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Revised: 12/02/2023] [Accepted: 12/18/2023] [Indexed: 12/26/2023]
Abstract
Horsehair worms (Nematomorpha: Gordioidea) are endoparasites of terrestrial arthropods, of which two species, Chordodes japonensis and C. formosanus, may have been historically confused due to their morphological similarity. In this study, we conducted field surveys and laboratory parasite inoculation experiments to clarify the characteristics and differences in host range and specificity between the two species. The field surveys revealed that the host ranges of the two species are markedly different. C. formosanus parasitized diverse mantids, while C. japonensis infected only species in the genus Tenodera, as predicted in previous studies. However, the two species had one mantid host, T. angustipennis in common. Parasite inoculation experiments using three species of mantids, revealed parasitism in each of the host-parasite combinations same as in the field study. These results suggest that the observed differences in host patterns are due to physiological factors between the host and parasite. Furthermore, cross-testing conducted on the shared host T. angustipennis showed that the two species coexisted within the same host in some cases, suggesting that the competitive exclusivity of the two species is low. This study also presents a tentative list of host ranges for the two species, comparing and integrating information from this and previous studies. However, the possibility remains that the host ranges of both species may be more diverse.
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Affiliation(s)
- Shotaro Tani
- Department of Bioresource Science, Graduate School of Integrated Science for Life, Hiroshima University, 1-4-4 Kagamiyama, Higashihiroshima, Hiroshima 739-8528, Japan.
| | - Pamela Afi Tettey
- Department of Bioresource Science, Graduate School of Integrated Science for Life, Hiroshima University, 1-4-4 Kagamiyama, Higashihiroshima, Hiroshima 739-8528, Japan
| | - Rion Maruta
- Department of Bioresource Science, Graduate School of Integrated Science for Life, Hiroshima University, 1-4-4 Kagamiyama, Higashihiroshima, Hiroshima 739-8528, Japan
| | - Atsuya Kodama
- Department of Bioresource Science, Graduate School of Integrated Science for Life, Hiroshima University, 1-4-4 Kagamiyama, Higashihiroshima, Hiroshima 739-8528, Japan
| | - Hidetoshi Saito
- Department of Bioresource Science, Graduate School of Integrated Science for Life, Hiroshima University, 1-4-4 Kagamiyama, Higashihiroshima, Hiroshima 739-8528, Japan
| | - Koichiro Kawai
- Department of Bioresource Science, Graduate School of Integrated Science for Life, Hiroshima University, 1-4-4 Kagamiyama, Higashihiroshima, Hiroshima 739-8528, Japan
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4
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Strauss AT, Suh DC, Galbraith K, Coker SM, Schroeder K, Brandon C, Warburton EM, Yabsley MJ, Cleveland CA. Mysterious microsporidians: springtime outbreaks of disease in Daphnia communities in shallow pond ecosystems. Oecologia 2024; 204:303-314. [PMID: 37470872 DOI: 10.1007/s00442-023-05421-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 07/09/2023] [Indexed: 07/21/2023]
Abstract
Parasites can play key roles in ecosystems, especially when they infect common hosts that play important ecological roles. Daphnia are critical grazers in many lentic freshwater ecosystems and typically reach peak densities in early spring. Daphnia have also become prominent model host organisms for the field of disease ecology, although most well-studied parasites infect them in summer or fall. Here, we report field patterns of virulent microsporidian parasites that consistently infect Daphnia in springtime, in a set of seven shallow ponds in Georgia, USA, sampled every 3-4 weeks for 18 months. We detected two distinct parasite taxa, closely matching sequences of Pseudoberwaldia daphniae and Conglomerata obtusa, both infecting all three resident species of Daphnia: D. ambigua, D. laevis, and D. parvula. To our knowledge, neither parasite has been previously reported in any of these host species or anywhere in North America. Infection prevalence peaked consistently in February-May, but the severity of these outbreaks differed substantially among ponds. Moreover, host species differed markedly in terms of their maximum infection prevalence (5% [D. parvula] to 72% [D. laevis]), mean reduction of fecundity when infected (70.6% [D. ambigua] to 99.8% [D. laevis]), mean spore yield (62,000 [D. parvula] to 377,000 [D. laevis] per host), and likelihood of being infected by each parasite. The timing and severity of the outbreaks suggests that these parasites could be impactful members of these shallow freshwater ecosystems, and that the strength of their effects is likely to hinge on the composition of ponds' zooplankton communities.
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Affiliation(s)
- Alexander T Strauss
- Odum School of Ecology, University of Georgia, Athens, GA, USA.
- Center for the Ecology of Infectious Diseases, University of Georgia, Athens, GA, USA.
- River Basin Center, University of Georgia, Athens, GA, USA.
| | - Daniel C Suh
- Odum School of Ecology, University of Georgia, Athens, GA, USA
- Center for the Ecology of Infectious Diseases, University of Georgia, Athens, GA, USA
| | - Kate Galbraith
- Odum School of Ecology, University of Georgia, Athens, GA, USA
| | - Sarah M Coker
- Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
| | - Katie Schroeder
- Odum School of Ecology, University of Georgia, Athens, GA, USA
| | | | - Elizabeth M Warburton
- Odum School of Ecology, University of Georgia, Athens, GA, USA
- Center for the Ecology of Infectious Diseases, University of Georgia, Athens, GA, USA
| | - Michael J Yabsley
- Center for the Ecology of Infectious Diseases, University of Georgia, Athens, GA, USA
- Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, USA
| | - Christopher A Cleveland
- Center for the Ecology of Infectious Diseases, University of Georgia, Athens, GA, USA
- Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
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5
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Virgilio LR, da Silva Lima F, Keppeler EC, Takemoto RM, Camargo LMA, de Oliveira Meneguetti DU. Endoparasite Communities of Fish at Different Trophic Levels in the Western Brazilian Amazon: Human, Environmental and Seasonal Influence. Acta Parasitol 2023; 68:612-636. [PMID: 37395992 DOI: 10.1007/s11686-023-00685-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 05/08/2023] [Indexed: 07/04/2023]
Abstract
PURPOSE The composition of the fish parasite community depends on several factors related to the environment, the host and its biology. This study aimed to evaluate the influence of environmental factors in anthropized and conserved areas on the endoparasite community structure in fish at different trophic levels, in addition to verifying that some species of Digenea are indicators of conserved environments. METHODS The study was carried out in the Upper Juruá River region, Western Amazon, Brazil. Six sampling sites were selected in this region and grouped in conserved and degraded environments. Fish were caught from periods of drought and flood, using passive and active sampling methods. Fish collected were measured, weighed, necropsied and the parasites found were counted, fixed, and subjected to morphological analysis. Physical and chemical variables and environmental characteristics were measured in all sites. RESULTS The present study demonstrated that environmental variables in a floodplain system can influence the richness, diversity, composition and abundance of endoparasites in hosts at different trophic levels. In addition, anthropized environments may favor the abundance of some generalist parasites and present a more homogeneous biota between seasonal periods compared to conserved environments. CONCLUSION Study contributed with information supporting the importance of conservation of aquatic environments, and demonstrated that fish parasites can be excellent indicators of environments.
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Affiliation(s)
- Lucena Rocha Virgilio
- Programa de Pós-Graduação em Biodiversidade e Biotecnologia, Bionorte, Universidade Federal do Acre, Rio Branco, Acre, Brazil.
| | - Fabricia da Silva Lima
- Laboratório de Ecologia Aquática, Universidade Federal do Acre, Campus Floresta, Cruzeiro do Sul, Acre, Brazil
| | - Erlei Cassiano Keppeler
- Laboratório de Ecologia Aquática, Universidade Federal do Acre, Campus Floresta, Cruzeiro do Sul, Acre, Brazil
| | - Ricardo Massato Takemoto
- Núcleo de Pesquisas em Limnologia, Ictiologia e Aquicultura, Laboratório de Ictioparasitologia, Universidade Estadual de Maringá, Maringá, Paraná, Brazil
| | | | - Dionatas Ulises de Oliveira Meneguetti
- Programa de Pós-Graduação em Biodiversidade e Biotecnologia, Bionorte, Universidade Federal do Acre, Rio Branco, Acre, Brazil
- Laboratório de Medicina Tropical, Universidade Federal do Acre, Rio Branco, Acre, Brazil
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6
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Born-Torrijos A, Riekenberg P, van der Meer MTJ, Nachev M, Sures B, Thieltges DW. Parasite effects on host's trophic and isotopic niches. Trends Parasitol 2023; 39:749-759. [PMID: 37451950 DOI: 10.1016/j.pt.2023.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 06/09/2023] [Accepted: 06/09/2023] [Indexed: 07/18/2023]
Abstract
Wild animals are usually infected with parasites that can alter their hosts' trophic niches in food webs as can be seen from stable isotope analyses of infected versus uninfected individuals. The mechanisms influencing these effects of parasites on host isotopic values are not fully understood. Here, we develop a conceptual model to describe how the alteration of the resource intake or the internal resource use of hosts by parasites can lead to differences of trophic and isotopic niches of infected versus uninfected individuals and ultimately alter resource flows through food webs. We therefore highlight that stable isotope studies inferring trophic positions of wild organisms in food webs would benefit from routine identification of their infection status.
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Affiliation(s)
- Ana Born-Torrijos
- Department of Coastal Systems, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, Texel, The Netherlands.
| | - Philip Riekenberg
- Department of Marine Microbiology and Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, Texel, The Netherlands
| | - Marcel T J van der Meer
- Department of Marine Microbiology and Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, Texel, The Netherlands
| | - Milen Nachev
- Department of Aquatic Ecology and Centre for Water and Environmental Research, University of Duisburg-Essen, Universitätsstr. 5, 45141 Essen, Germany
| | - Bernd Sures
- Department of Aquatic Ecology and Centre for Water and Environmental Research, University of Duisburg-Essen, Universitätsstr. 5, 45141 Essen, Germany; Research Center One Health Ruhr, Research Alliance Ruhr, University Duisburg-Essen, Universitätsstr. 5, 45141 Essen, Germany
| | - David W Thieltges
- Department of Coastal Systems, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, Texel, The Netherlands; Groningen Institute for Evolutionary Life-Sciences, GELIFES, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
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7
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Suzuki SS, Baba YG, Toju H. Dynamics of species-rich predator-prey networks and seasonal alternations of core species. Nat Ecol Evol 2023; 7:1432-1443. [PMID: 37460838 DOI: 10.1038/s41559-023-02130-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Accepted: 06/16/2023] [Indexed: 09/08/2023]
Abstract
In nature, entangled webs of predator-prey interactions constitute the backbones of ecosystems. Uncovering the network architecture of such trophic interactions has been recognized as the essential step for exploring species with great impacts on ecosystem-level phenomena and functions. However, it has remained a major challenge to reveal how species-rich networks of predator-prey interactions are continually reshaped through time in the wild. Here, we show that dynamics of species-rich predator-prey interactions can be characterized by remarkable network structural changes and alternations of species with greatest impacts on community processes. On the basis of high-throughput detection of prey DNA from 1,556 spider individuals collected in a grassland ecosystem, we reconstructed dynamics of interaction networks involving, in total, 50 spider species and 974 prey species and strains through 8 months. The networks were compartmentalized into modules (groups) of closely interacting predators and prey in each month. Those modules differed in detritus/grazing food chain properties, forming complex fission-fusion dynamics of belowground and aboveground energy channels across the seasons. The substantial shifts of network structure entailed alternations of spider species located at the core positions within the entangled webs of interactions. These results indicate that knowledge of dynamically shifting food webs is crucial for understanding temporally varying roles of 'core species' in ecosystem processes.
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Affiliation(s)
- Sayaka S Suzuki
- Center for Ecological Research, Kyoto University, Otsu, Japan.
| | - Yuki G Baba
- Institute for Agro-Environmental Sciences, NARO, Tsukuba, Japan
| | - Hirokazu Toju
- Center for Ecological Research, Kyoto University, Otsu, Japan.
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8
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Cunha TJ, de Medeiros BAS, Lord A, Sørensen MV, Giribet G. Rampant loss of universal metazoan genes revealed by a chromosome-level genome assembly of the parasitic Nematomorpha. Curr Biol 2023; 33:3514-3521.e4. [PMID: 37467752 DOI: 10.1016/j.cub.2023.07.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 05/21/2023] [Accepted: 07/03/2023] [Indexed: 07/21/2023]
Abstract
Parasites may manipulate host behavior to increase the odds of transmission or to reach the proper environment to complete their life cycle.1,2 Members of the phylum Nematomorpha (known as horsehair worms, hairworms, or Gordian worms) are large endoparasites that affect the behavior of their arthropod hosts. In terrestrial hosts, they cause erratic movements toward bodies of water,3,4,5,6 where the adult worm emerges from the host to find mates for reproduction. We present a chromosome-level genome assembly for the freshwater Acutogordius australiensis and a draft assembly for one of the few known marine species, Nectonema munidae. The assemblies span 201 Mbp and 213 Mbp in length (N50: 38 Mbp and 716 Kbp), respectively, and reveal four chromosomes in Acutogordius, which are largely rearranged compared to the inferred ancestral condition in animals. Both nematomorph genomes have a relatively low number of genes (11,114 and 8,717, respectively) and lack a high proportion (∼30%) of universal single-copy metazoan orthologs (BUSCO genes7). We demonstrate that missing genes are not an artifact of the assembly process, with the majority of missing orthologs being shared by the two independent assemblies. Missing BUSCOs are enriched for Gene Ontology (GO) terms associated with the organization of cilia and cell projections in other animals. We show that most cilium-related genes conserved across eukaryotes have been lost in Nematomorpha, providing a molecular basis for the suspected absence of ciliary structures in these animals.
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Affiliation(s)
- Tauana J Cunha
- Museum of Comparative Zoology, Department of Organismic and Evolutionary Biology, Harvard University, 26 Oxford Street, Cambridge, MA 02138, USA; Field Museum of Natural History, 1400 S DuSable Lake Shore Drive, Chicago, IL 60605, USA.
| | - Bruno A S de Medeiros
- Museum of Comparative Zoology, Department of Organismic and Evolutionary Biology, Harvard University, 26 Oxford Street, Cambridge, MA 02138, USA; Field Museum of Natural History, 1400 S DuSable Lake Shore Drive, Chicago, IL 60605, USA
| | - Arianna Lord
- Museum of Comparative Zoology, Department of Organismic and Evolutionary Biology, Harvard University, 26 Oxford Street, Cambridge, MA 02138, USA
| | - Martin V Sørensen
- Natural History Museum of Denmark, University of Copenhagen, Universitetsparken 15, DK-2100 Copenhagen, Denmark
| | - Gonzalo Giribet
- Museum of Comparative Zoology, Department of Organismic and Evolutionary Biology, Harvard University, 26 Oxford Street, Cambridge, MA 02138, USA
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9
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Forti LR, Szabo JK, Japyassú HF. Host manipulation by parasites through the lens of Niche Construction Theory. Behav Processes 2023:104907. [PMID: 37352944 DOI: 10.1016/j.beproc.2023.104907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 06/17/2023] [Accepted: 06/19/2023] [Indexed: 06/25/2023]
Abstract
The effect of parasites on host behaviour is generally considered an example of the extended phenotype, implying that parasite genes alter host behaviour to benefit the parasite. While the extended phenotype is a valid perspective supported by empirical examples, this approach was proposed from an evolutionary perspective and it does not fully explain all processes that occur at ecological time scales. For instance, the roles of the ontogenetic environment, memory and learning in forming the host phenotype are not explicitly mentioned. Furthermore, the cumulative effect of diverse populations or communities of parasites on host phenotype cannot be attributed to a particular genotype, much less to a particular gene. Building on the idea that the behaviour of a host is the result of a complex process, which certainly goes beyond a specific parasite gene, we use Niche Construction Theory to describe certain systems that are not generally the main focus in the extended phenotype (EP) model. We introduce three niche construction models with corresponding empirical examples that capture the diversity and complexity of host-parasite interactions, providing predictions that simpler models cannot generate. We hope that this novel perspective will inspire further research on the topic, given the impact of ecological factors on both short-, and long-term effects of parasitism.
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Affiliation(s)
- Lucas Rodriguez Forti
- Instituto de Biologia, Universidade Federal da Bahia, Rua Barão de Jeremoabo, 668 - Campus de Ondina CEP: 40170-115 Salvador - Bahia, Brazil; Departamento de Biociências, Universidade Federal Rural do Semi-Árido, Av. Francisco Mota, 572 - Bairro Costa e Silva, 59625-900, Mossoró - Rio Grande do Norte, Brazil.
| | - Judit K Szabo
- Instituto de Biologia, Universidade Federal da Bahia, Rua Barão de Jeremoabo, 668 - Campus de Ondina CEP: 40170-115 Salvador - Bahia, Brazil; College of Engineering, IT and Environment, Charles Darwin University, Casuarina, Northern Territory 0909, Australia
| | - Hilton F Japyassú
- Instituto de Biologia, Universidade Federal da Bahia, Rua Barão de Jeremoabo, 668 - Campus de Ondina CEP: 40170-115 Salvador - Bahia, Brazil; INCT-INTREE: Instituto Nacional de Ciência e Tecnologia para estudos Interdisciplinares e Transdisciplinares em Ecologia e Evolução, Universidade Federal da Bahia
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10
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Tanaka T, Ueda R, Sato T. Seasonal ecosystem linkages contribute to the maintenance of migratory polymorphism in a salmonid population. Proc Biol Sci 2023; 290:20230126. [PMID: 36946118 PMCID: PMC10031421 DOI: 10.1098/rspb.2023.0126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 02/23/2023] [Indexed: 03/23/2023] Open
Abstract
The influence of resource subsidies on animal growth, survival and reproduction is well understood, but their ultimate effects on life history have been less explored. Some wild species have a partially migratory life history, wherein migration is dictated based upon threshold traits regulated in part by the seasonal availability of resources. We conducted a large-scale field manipulation experiment where we provided a terrestrial invertebrate subsidy to red-spotted masu salmon. Individuals in stream reaches that received a subsidy had, on average, a 53% increase in growth rate relative to those in control reaches. This increased growth resulted in a greater proportion of individuals reaching the threshold body size and smolting in the autumn. Consequently, 19-55% of females in subsidized reaches became migratory, whereas 0-14% became migratory in the control reaches. Our findings highlight seasonal ecosystem linkage as a key ecosystem property for maintaining migratory polymorphism in partially migratory animals.
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Affiliation(s)
- Tatsuya Tanaka
- Department of Biology, Graduate School of Sciences, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe 657-8501, Japan
| | - Rui Ueda
- Department of Biology, Graduate School of Sciences, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe 657-8501, Japan
| | - Takuya Sato
- Department of Biology, Graduate School of Sciences, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe 657-8501, Japan
- Center for Ecological Research, Kyoto University, Hirano 2-509-3, Otsu, Shiga 520-2113, Japan
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11
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Hesse T, Nachev M, Khaliq S, Jochmann MA, Franke F, Scharsack JP, Kurtz J, Sures B, Schmidt TC. A new technique to study nutrient flow in host-parasite systems by carbon stable isotope analysis of amino acids and glucose. Sci Rep 2023; 13:1054. [PMID: 36658208 PMCID: PMC9852285 DOI: 10.1038/s41598-022-24933-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 11/22/2022] [Indexed: 01/20/2023] Open
Abstract
Stable isotope analysis of individual compounds is emerging as a powerful tool to study nutrient origin and conversion in host-parasite systems. We measured the carbon isotope composition of amino acids and glucose in the cestode Schistocephalus solidus and in liver and muscle tissues of its second intermediate host, the three-spined stickleback (Gasterosteus aculeatus), over the course of 90 days in a controlled infection experiment. Similar linear regressions of δ13C values over time and low trophic fractionation of essential amino acids indicate that the parasite assimilates nutrients from sources closely connected to the liver metabolism of its host. Biosynthesis of glucose in the parasite might occur from the glucogenic precursors alanine, asparagine and glutamine and with an isotope fractionation of - 2 to - 3 ‰ from enzymatic reactions, while trophic fractionation of glycine, serine and threonine could be interpreted as extensive nutrient conversion to fuel parasitic growth through one-carbon metabolism. Trophic fractionation of amino acids between sticklebacks and their diets was slightly increased in infected compared to uninfected individuals, which could be caused by increased (immune-) metabolic activities due to parasitic infection. Our results show that compound-specific stable isotope analysis has unique opportunities to study host and parasite physiology.
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Affiliation(s)
- Tobias Hesse
- Instrumental Analytical Chemistry, University of Duisburg-Essen, Universitätsstr. 5, 45141, Essen, Germany
| | - Milen Nachev
- Aquatic Ecology, University of Duisburg-Essen, Universitätsstr. 5, 45141, Essen, Germany.,Centre for Water and Environmental Research, University of Duisburg-Essen, Universitätsstr. 5, 45141, Essen, Germany
| | - Shaista Khaliq
- Instrumental Analytical Chemistry, University of Duisburg-Essen, Universitätsstr. 5, 45141, Essen, Germany
| | - Maik A Jochmann
- Instrumental Analytical Chemistry, University of Duisburg-Essen, Universitätsstr. 5, 45141, Essen, Germany. .,Centre for Water and Environmental Research, University of Duisburg-Essen, Universitätsstr. 5, 45141, Essen, Germany.
| | - Frederik Franke
- Institute for Evolution & Biodiversity, University of Münster, Hüfferstr. 1, 48149, Münster, Germany.,Bavarian State Institute of Forestry, Hans-Carl-Von-Carlowitz-Platz 1, 85354, Freising, Germany
| | - Jörn P Scharsack
- Institute for Evolution & Biodiversity, University of Münster, Hüfferstr. 1, 48149, Münster, Germany.,Thünen Institute of Fisheries Ecology, Herwigstr. 31, 27572, Bremerhaven, Germany
| | - Joachim Kurtz
- Institute for Evolution & Biodiversity, University of Münster, Hüfferstr. 1, 48149, Münster, Germany
| | - Bernd Sures
- Aquatic Ecology, University of Duisburg-Essen, Universitätsstr. 5, 45141, Essen, Germany.,Centre for Water and Environmental Research, University of Duisburg-Essen, Universitätsstr. 5, 45141, Essen, Germany
| | - Torsten C Schmidt
- Instrumental Analytical Chemistry, University of Duisburg-Essen, Universitätsstr. 5, 45141, Essen, Germany.,Centre for Water and Environmental Research, University of Duisburg-Essen, Universitätsstr. 5, 45141, Essen, Germany
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12
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Lisnerová M, Martinek IN, Alama-Bermejo G, Bouberlová K, Schaeffner BC, Nkabi N, Holzer AS, Bartošová-Sojková P. An ancient alliance: Matching evolutionary patterns of cartilaginous fishes (Elasmobranchii) and chloromyxid parasites (Myxozoa). INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2022; 103:105346. [PMID: 35932999 DOI: 10.1016/j.meegid.2022.105346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 07/27/2022] [Accepted: 07/30/2022] [Indexed: 06/15/2023]
Abstract
Myxozoa is a group of endoparasitic cnidarians covering almost 2600 species but merely 53 species, mostly from the genus Chloromyxum, have been reported from sharks, rays, and skates (Elasmobranchii). Elasmobranchs play a key role in the study of evolutionary trajectories of myxozoans as they represent ancestral vertebrate hosts. Our study provides new data on Chloromyxum spp. from 57 elasmobranchs, covering 20 species from geographical regions and host groups not previously investigated, such as Lamniformes and Hexanchiformes, the most basal phylogenetic shark lineage. In total, 28% of elasmobranchs were infected with Chloromyxum spp., indicating high diversity. Of the seven distinguished species, six are formally described based on morphological, morphometric, and genetic (18S rDNA) data. Comprehensive co-phylogenetic analyses and ancestral state reconstruction revealed that parasite and host phylogenies are clearly correlated, resulting in a distinct phylogenetic separation of chloromyxids from selachid (shark) vs. batoid (ray and skate) hosts. Species infecting the most ancient elasmobranchs formed a sublineage, branching off in the middle of the Chloromyxum sensu stricto clade. Our findings indicate that chloromyxids likely invaded an ancestral elasmobranch prior the time of divergence of shark and batoid lineages. Our analyses did not show a clear phylogeographic pattern of Chloromyxum parasites, probably due to the cosmopolitan distribution and migratory behaviour of many elasmobranch hosts, but geographical sampling must be extended to confirm or refute this observation. This study provides a complex view on species diversity, phylogeny, evolution, host-parasite co-phylogeny, and the phylogeographic origin of Chloromyxum species from elasmobranchs. Our results highlight the importance of adding missing data from previously un- or undersampled geographical regions and host species which results in a more accurate estimate of myxozoan biodiversity and a better understanding of the evolution of this parasite group in their hosts and in the different oceans of our planet.
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Affiliation(s)
- Martina Lisnerová
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic; Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Inga Nicole Martinek
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic; Department of Zoology, Swedish Museum of Natural History, Stockholm, Sweden
| | - Gema Alama-Bermejo
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic; Centro de Investigación Aplicada y Transferencia Tecnológica en Recursos Marinos Almirante Storni (CIMAS), CCT CONICET - CENPAT, San Antonio Oeste, Argentina; Division of Fish Health, University of Veterinary Medicine, Vienna, Austria
| | - Kateřina Bouberlová
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Bjoern C Schaeffner
- Institute for Experimental Pathology at Keldur, University of Iceland, Reykjavík, Iceland; Water Research Group, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - Nomfundo Nkabi
- KwaZulu-Natal Sharks Board, Umhlanga Rocks, South Africa
| | - Astrid S Holzer
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic; Division of Fish Health, University of Veterinary Medicine, Vienna, Austria
| | - Pavla Bartošová-Sojková
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic.
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13
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Koltz AM, Civitello DJ, Becker DJ, Deem SL, Classen AT, Barton B, Brenn-White M, Johnson ZE, Kutz S, Malishev M, Preston DL, Vannatta JT, Penczykowski RM, Ezenwa VO. Sublethal effects of parasitism on ruminants can have cascading consequences for ecosystems. Proc Natl Acad Sci U S A 2022; 119:e2117381119. [PMID: 35533278 PMCID: PMC9171767 DOI: 10.1073/pnas.2117381119] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 03/17/2022] [Indexed: 12/29/2022] Open
Abstract
Parasitic infections are common, but how they shape ecosystem-level processes is understudied. Using a mathematical model and meta-analysis, we explored the potential for helminth parasites to trigger trophic cascades through lethal and sublethal effects imposed on herbivorous ruminant hosts after infection. First, using the model, we linked negative effects of parasitic infection on host survival, fecundity, and feeding rate to host and producer biomass. Our model, parameterized with data from a well-documented producer–caribou–helminth system, reveals that even moderate impacts of parasites on host survival, fecundity, or feeding rate can have cascading effects on ruminant host and producer biomass. Second, using meta-analysis, we investigated the links between helminth infections and traits of free-living ruminant hosts in nature. We found that helminth infections tend to exert negative but sublethal effects on ruminant hosts. Specifically, infection significantly reduces host feeding rates, body mass, and body condition but has weak and highly variable effects on survival and fecundity. Together, these findings suggest that while helminth parasites can trigger trophic cascades through multiple mechanisms, overlooked sublethal effects on nonreproductive traits likely dominate their impacts on ecosystems. In particular, by reducing ruminant herbivory, pervasive helminth infections may contribute to a greener world.
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Affiliation(s)
- Amanda M. Koltz
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130
| | | | | | - Sharon L. Deem
- Saint Louis Zoo Institute for Conservation Medicine, Saint Louis, MO 63110
| | - Aimée T. Classen
- Ecology and Evolutionary Biology Department, University of Michigan, Ann Arbor, MI 48109
| | - Brandon Barton
- Department of Biological Sciences, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Maris Brenn-White
- Saint Louis Zoo Institute for Conservation Medicine, Saint Louis, MO 63110
| | - Zoë E. Johnson
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS 39762
| | - Susan Kutz
- Department of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada
| | | | - Daniel L. Preston
- Department of Fish, Wildlife and Conservation Biology, Colorado State University, Fort Collins, CO 80523
| | - J. Trevor Vannatta
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907
| | | | - Vanessa O. Ezenwa
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06511
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14
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Infection patterns and new definitive host records for New Zealand gordiid hairworms (phylum Nematomorpha). Parasitol Int 2022; 90:102598. [PMID: 35568302 DOI: 10.1016/j.parint.2022.102598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 04/24/2022] [Accepted: 05/09/2022] [Indexed: 11/20/2022]
Abstract
Some parasites modify the phenotype of their host in order to increase transmission to another host or to an environment suitable for reproduction. This phenomenon, known as host manipulation, is found across many parasite taxa. Freshwater hairworms are known for the behavioural changes they cause in their terrestrial arthropod hosts, increasing their likelihood of entering water to exit the host and reproduce. Understanding how infected arthropods move around in the natural environment could help uncover alterations in spatial distribution or movement induced by hairworms in their terrestrial definitive hosts. Moreover, few hairworm-host records exist for New Zealand, so any additional record could help elucidate their true host specificity. Here, we investigated whether infected terrestrial arthropods were more likely to approach streams in two subalpine communities of invertebrates, using a spatial grid of specialised pitfall traps. Although hairworm infection could not explain the movements of arthropod hosts near streams, we found several new host records for hairworms, including the first records for the recently described Gordionus maori. We also found some new host-parasite associations for mermithid nematodes. These records show that the host specificity of hairworms is quite low, suggesting that their diversity and distribution may be greater than what is currently known for New Zealand.
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15
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Campanini FP, Merlo MJ, Méndez Casariego MA, Parietti M. Diversity and dynamics in larval digenean assemblages parasitizing Heleobia parchappii in a freshwater shallow lake from the Southeastern Pampa plain, Argentina. Parasitology 2022; 149:347-355. [PMID: 35264266 PMCID: PMC11010548 DOI: 10.1017/s0031182021001888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 10/02/2021] [Accepted: 10/18/2021] [Indexed: 11/06/2022]
Abstract
Digeneans have important roles within ecosystems; however, it is estimated that only 14% of the species have been described. Therefore, before being able to detail their role, digenean species’ identification and the diversity present in the ecosystems must be known. In this study, the diversity and the temporal-spatial dynamics of larval digeneans in the freshwater snail Heleobia parchappii were analysed in a shallow lake. Specimens of H. parchappii were collected seasonally at three points during one year and a total of 2871 molluscs were analysed. A total of 23 species of digenea were registered and both the overall prevalence and the composition of the assemblages presented temporal and spatial variations, responding to the differential environmental conditions characteristics (anthropic effect, presence of native forests, and differential use of the habitat by the definitive hosts) of three sampled sites. The assemblages of larval digenean in their first intermediate host support the idea that this area is of great importance in biodiversity, and could be endemic areas of some species of digenean that use reptiles, amphibians and bats as hosts, groups that are at risk of conservation. Protection of these environments is a fundamental pillar in the policies for the conservation of wild flora and fauna.
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Affiliation(s)
- Florencia Paz Campanini
- Laboratorio de Parasitología, Universidad Nacional de Mar del Plata (UNMDP), Mar del Plata, Bueno Aires, Argentina
| | - Matías Javier Merlo
- Laboratorio de Parasitología, Universidad Nacional de Mar del Plata (UNMDP), Mar del Plata, Bueno Aires, Argentina
- Instituto de Investigaciones en Producción Sanidad y Ambiente (CONICET-UNMDP), Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - María Agustina Méndez Casariego
- Laboratorio de Parasitología, Universidad Nacional de Mar del Plata (UNMDP), Mar del Plata, Bueno Aires, Argentina
- Instituto de Investigaciones en Producción Sanidad y Ambiente (CONICET-UNMDP), Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Manuela Parietti
- Laboratorio de Parasitología, Universidad Nacional de Mar del Plata (UNMDP), Mar del Plata, Bueno Aires, Argentina
- Instituto de Investigaciones en Producción Sanidad y Ambiente (CONICET-UNMDP), Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
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16
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Gagne RB, Crooks KR, Craft ME, Chiu ES, Fountain-Jones NM, Malmberg JL, Carver S, Funk WC, VandeWoude S. Parasites as conservation tools. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2022; 36:e13719. [PMID: 33586245 DOI: 10.1111/cobi.13719] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 02/08/2021] [Indexed: 06/12/2023]
Abstract
Parasite success typically depends on a close relationship with one or more hosts; therefore, attributes of parasitic infection have the potential to provide indirect details of host natural history and are biologically relevant to animal conservation. Characterization of parasite infections has been useful in delineating host populations and has served as a proxy for assessment of environmental quality. In other cases, the utility of parasites is just being explored, for example, as indicators of host connectivity. Innovative studies of parasite biology can provide information to manage major conservation threats by using parasite assemblage, prevalence, or genetic data to provide insights into the host. Overexploitation, habitat loss and fragmentation, invasive species, and climate change are major threats to animal conservation, and all of these can be informed by parasites.
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Affiliation(s)
- Roderick B Gagne
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - Kevin R Crooks
- Department of Fish, Wildlife, and Conservation Biology, Colorado State University, Fort Collins, Colorado, USA
| | - Meggan E Craft
- Department of Veterinary Population Medicine, University of Minnesota, St Paul, Minnesota, USA
| | - Elliott S Chiu
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | | | - Jennifer L Malmberg
- Department of Veterinary Sciences, Wyoming State Veterinary Laboratory, University of Wyoming, Laramie, Wyoming, USA
| | - Scott Carver
- School of Natural Sciences, University of Tasmania, Hobart, Tasmania, Australia
| | - W Chris Funk
- Graduate Degree Program in Ecology, Department of Biology, Colorado State University, Fort Collins, Colorado, USA
| | - Sue VandeWoude
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA
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17
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Doherty JF, Poulin R. The return to land: association between hairworm infection and aquatic insect development. Parasitol Res 2022; 121:667-673. [PMID: 35067741 DOI: 10.1007/s00436-021-07410-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 12/14/2021] [Indexed: 11/30/2022]
Abstract
Host manipulation by parasites can shape host behaviour, community structure, and the flow of energy through food webs. A well-known example of host manipulation comes from hairworms (phylum Nematomorpha), which somehow cause their terrestrial insect definitive hosts to enter water, a phenomenon that has received lots of attention in recent years. However, little focus has been directed towards the interactions between hairworms and their aquatic insect hosts and the return of dormant hairworms from water to land. Here, we ask whether hairworm cyst infections impact, either directly or indirectly, the life history of their aquatic transport hosts. By observing the development of last-instar Olinga jeanae (Trichoptera: Conoesucidae) caddisfly larvae naturally infected with Gordius-type hairworm cysts under controlled conditions, we found that higher numbers of cysts per infected caddisfly correlated with a decrease in time to pupation. These new observations suggest that, apart from the striking host manipulation that brings the parasite from land to water, the presence of dormant hairworms is associated with changes in the development of their aquatic hosts, either through direct or indirect mechanisms, which may accelerate their transition from water to land.
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Affiliation(s)
| | - Robert Poulin
- Department of Zoology, University of Otago, Dunedin, New Zealand
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18
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Abstract
In less than 25 y, the field of animal genome science has transformed from a discipline seeking its first glimpses into genome sequences across the Tree of Life to a global enterprise with ambitions to sequence genomes for all of Earth's eukaryotic diversity [H. A. Lewin et al., Proc. Natl. Acad. Sci. U.S.A. 115, 4325-4333 (2018)]. As the field rapidly moves forward, it is important to take stock of the progress that has been made to best inform the discipline's future. In this Perspective, we provide a contemporary, quantitative overview of animal genome sequencing. We identified the best available genome assemblies in GenBank, the world's most extensive genetic database, for 3,278 unique animal species across 24 phyla. We assessed taxonomic representation, assembly quality, and annotation status for major clades. We show that while tremendous taxonomic progress has occurred, stark disparities in genomic representation exist, highlighted by a systemic overrepresentation of vertebrates and underrepresentation of arthropods. In terms of assembly quality, long-read sequencing has dramatically improved contiguity, whereas gene annotations are available for just 34.3% of taxa. Furthermore, we show that animal genome science has diversified in recent years with an ever-expanding pool of researchers participating. However, the field still appears to be dominated by institutions in the Global North, which have been listed as the submitting institution for 77% of all assemblies. We conclude by offering recommendations for improving genomic resource availability and research value while also broadening global representation.
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19
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Okada K, Sakai M, Gomi T, Iwamoto A, Negishi JN, Nunokawa M. Seasonal variations of
137
Cs
concentration in freshwater charr through uptake and metabolism in 1–2 years after the Fukushima accident. Ecol Res 2021. [DOI: 10.1111/1440-1703.12266] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Kengo Okada
- Graduate School of Agriculture Tokyo University of Agriculture and Technology Tokyo Japan
| | - Masaru Sakai
- Fukushima Regional Collaborative Research Center National Institute for Environmental Studies Fukushima Japan
| | - Takashi Gomi
- Graduate School of Agriculture Tokyo University of Agriculture and Technology Tokyo Japan
| | - Aimu Iwamoto
- Graduate School of Agriculture Tokyo University of Agriculture and Technology Tokyo Japan
| | - Junjiro N. Negishi
- Faculty of Environmental Earth Science Hokkaido University Hokkaido Japan
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20
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Vannatta JT, Minchella DJ. The influence of parasitism on producers and nutrients in mesocosm ecosystems. FOOD WEBS 2021. [DOI: 10.1016/j.fooweb.2021.e00204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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21
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Effect of environmental variables and their interaction on gordiid hairworm larvae (Nematomorpha). J Helminthol 2021; 95:e47. [PMID: 34423756 DOI: 10.1017/s0022149x21000420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The different stages of the life cycle of parasites are important components of ecosystems. Changes in environmental conditions may affect free-living stages, host-parasite interactions and ecosystem functioning. The larvae of Chordodes nobilii, which belongs to the parasitic phylum Nematomorpha, are susceptible to extreme temperatures and different pollutants, but the effects of pH and moderate temperature variations have not been evaluated yet. Our objective was to assess the effect of temperature, pH and their interaction on the infectivity of C. nobilii larvae to Aedes aegypti larvae over time. Larvae were treated with factorial combinations of temperature (18, 23 and 28°C), pH (7, 8 and 9) and time periods (24 and 48 h). Results show a highly significant interaction among all variables. The highest infectivity was recorded at 18°C and pH 7 at 24 and 48 h, and the lowest one at 28°C and pH 8 at 24 and 48 h. Infectivity differed significantly among the three temperatures only at pH 8 and 48 h, decreasing with increasing temperature. Our study is the first report of the effect of pH on a Nematomorpha species and suggests that the infectivity of C. nobilii larvae may be affected negatively by an increase in temperature and its interaction with pH and time. Since parasites must be considered for a better understanding of the effects of stressors on freshwater ecosystems, our results may help in the design and analysis of studies of anthropogenic impact.
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22
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Szopieray K, Żbikowska E. Positive ecological roles of parasites. ACTA ZOOL ACAD SCI H 2021. [DOI: 10.17109/azh.67.3.289.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The traditional assessment of parasites by veterinarians and medical professionals is une-quivocally negative. In this minireview, we focus on the positive aspects of the presence of parasites in the environment. Most notably, the host-parasite system is a long-term interac-tion because parasites, despite their negative impact on the host, rarely lead to its death. We analysed three important aspects of the presence of parasites in the environment: (i) participation in the regulation community balance leading to changes in the dominance structure, the formation of trophic chains as well as the inclusion of new energy sources into the ecosystem, (ii) control of invasions of alien species to new areas through the im-pact on the adaptive abilities of invaders and (iii) efficient accumulation of heavy metals resulting from the physiological properties of parasite tissues, and thus providing the ad-ditional environmental pollution index. The presented examples show that parasites play an important role as ecosystem engineers, affecting the dynamic balance of ecosystems. The present review aims to challenge the stereotype of parasitism as an unambiguously negative interaction and show evidence of the significant impact of parasites on healthy functioning communities and environmental safety.
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23
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Towards a more healthy conservation paradigm: integrating disease and molecular ecology to aid biological conservation †. J Genet 2021. [PMID: 33622992 PMCID: PMC7371965 DOI: 10.1007/s12041-020-01225-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Parasites, and the diseases they cause, are important from an ecological and evolutionary perspective because they can negatively affect host fitness and can regulate host populations. Consequently, conservation biology has long recognized the vital role that parasites can play in the process of species endangerment and recovery. However, we are only beginning to understand how deeply parasites are embedded in ecological systems, and there is a growing recognition of the important ways in which parasites affect ecosystem structure and function. Thus, there is an urgent need to revisit how parasites are viewed from a conservation perspective and broaden the role that disease ecology plays in conservation-related research and outcomes. This review broadly focusses on the role that disease ecology can play in biological conservation. Our review specifically emphasizes on how the integration of tools and analytical approaches associated with both disease and molecular ecology can be leveraged to aid conservation biology. Our review first concentrates on disease-mediated extinctions and wildlife epidemics. We then focus on elucidating how host–parasite interactions has improved our understanding of the eco-evolutionary dynamics affecting hosts at the individual, population, community and ecosystem scales. We believe that the role of parasites as drivers and indicators of ecosystem health is especially an exciting area of research that has the potential to fundamentally alter our view of parasites and their role in biological conservation. The review concludes with a broad overview of the current and potential applications of modern genomic tools in disease ecology to aid biological conservation.
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24
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Feeding habits of Ictalurus punctatus in the downstream section of Nunome Dam reservoir in Japan. LANDSCAPE AND ECOLOGICAL ENGINEERING 2021. [DOI: 10.1007/s11355-021-00463-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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25
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Schmidt-Rhaesa A, Expósito López De Felipe JE, Martínez J. Primera cita de Gordius albopunctatus Müller, 1927 en la Península Ibérica (Nematomorpha: Gordioida Rauther, 1930). GRAELLSIA 2021. [DOI: 10.3989/graellsia.2021.v77.283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Se hace referencia a la primera cita de Gordius albopunctatus Müller, 1927 (Gordioida) de la península ibérica, a partir de un ejemplar macho y otro hembra capturados en la Sierra de Guadarrama (Madrid). Esta cita es la más meridional de su distribución de modo que se amplía notablemente su distribución biogeográfica.
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26
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Sato T, Ueda R, Takimoto G. The effects of resource subsidy duration in a detritus-based stream ecosystem: A mesocosm experiment. J Anim Ecol 2021; 90:1142-1151. [PMID: 33560517 DOI: 10.1111/1365-2656.13440] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 12/16/2020] [Indexed: 11/28/2022]
Abstract
Most resource subsidies are temporally variable, dynamically affecting the consumer populations, community structures and ecosystem functions of recipient ecosystems. Temporally variable resource subsidies are characterized by the duration, magnitude, timing and frequency of resource subsidy inputs. These different characteristics may have different mechanisms by which to affect recipient ecosystems. Few studies have examined the duration of resource subsidy inputs on recipient ecosystems, although there exist previous studies focusing on magnitude, timing and frequency. We provide the first experimental test of the effects of subsidy duration on a stream ecosystem by using an outdoor mesocosm experiment, in which we directly manipulated the subsidy duration (pulsed vs. prolonged) of terrestrial invertebrate input into the mesocosm. Given the same overall amount of terrestrial invertebrate subsidy was added, a prolonged subsidy allowed large-stage fish to effectively monopolize the subsidy over small-stage fish, which led small-stage fish to maintain their predation pressure on in-situ prey, that is, benthic invertebrates. On the other hand, a pulsed subsidy allowed small-stage fish to increase their feeding rate of the subsidy and to become away from foraging in-situ prey. Consequently, weaker indirect positive effects on in-situ benthic prey and leaf break-down rate were found with the prolonged versus pulsed subsidy. However, these indirect effects varied by the dominant benthic prey species, which differed in edibility for fish. Such predator-specific vulnerability of benthic prey can be important in mediating trophic cascades in detritus-based stream food webs. Phenological events that generate temporal subsidies (e.g. salmon spawning run and arthropod emergence) can be synchronized (pulsed) or desynchronized (prolonged) within and among species, depending on the degree of spatial and temporal environmental heterogeneity. The effects of subsidy duration would thus be important to better understand ecological processes in spatially and temporally coupled ecosystems.
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Affiliation(s)
- Takuya Sato
- Department of Biology, Graduate School of Sciences, Kobe University, Kobe, Japan
| | - Rui Ueda
- Department of Biology, Graduate School of Sciences, Kobe University, Kobe, Japan
| | - Gaku Takimoto
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
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Preston DL, Layden TJ, Segui LM, Falke LP, Brant SV, Novak M. Trematode parasites exceed aquatic insect biomass in Oregon stream food webs. J Anim Ecol 2020; 90:766-775. [PMID: 33368227 DOI: 10.1111/1365-2656.13409] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 11/16/2020] [Indexed: 11/30/2022]
Abstract
Although parasites are increasingly recognized for their ecosystem roles, it is often assumed that free-living organisms dominate animal biomass in most ecosystems and therefore provide the primary pathways for energy transfer. To examine the contributions of parasites to ecosystem energetics in freshwater streams, we quantified the standing biomass of trematodes and free-living organisms at nine sites in three streams in western Oregon, USA. We then compared the rates of biomass flow from snails Juga plicifera into trematode parasites relative to aquatic vertebrate predators (sculpin, cutthroat trout and Pacific giant salamanders). The trematode parasite community had the fifth highest dry biomass density among stream organisms (0.40 g/m2 ) and exceeded the combined biomass of aquatic insects. Only host snails (3.88 g/m2 ), sculpin (1.11 g/m2 ), trout (0.73 g/m2 ) and crayfish (0.43 g/m2 ) had a greater biomass. The parasite 'extended phenotype', consisting of trematode plus castrated host biomass, exceeded the individual biomass of every taxonomic group other than snails. The substantial parasite biomass stemmed from the high snail density and infection prevalence, and the large proportional mass of infected hosts that consisted of trematode tissue (M = 31% per snail). Estimates of yearly biomass transfer from snails into trematodes were slightly higher than the combined estimate of snail biomass transfer into the three vertebrate predators. Pacific giant salamanders accounted for 90% of the snail biomass consumed by predators. These results demonstrate that trematode parasites play underappreciated roles in the ecosystem energetics of some freshwater streams.
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Affiliation(s)
- Daniel L Preston
- Department of Forest and Wildlife Ecology, University of Wisconsin-Madison, Madison, WI, USA
| | | | - Leah M Segui
- Department of Integrative Biology, Oregon State University, Corvallis, OR, USA
| | - Landon P Falke
- Department of Forest and Wildlife Ecology, University of Wisconsin-Madison, Madison, WI, USA
| | - Sara V Brant
- Museum of Southwestern Biology, Division of Parasites, Department of Biology, University of New Mexico, Albuquerque, NM, USA
| | - Mark Novak
- Department of Integrative Biology, Oregon State University, Corvallis, OR, USA
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28
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Emerging helminthiases of song thrush (Turdus philomelos) in Central Europe. Parasitol Res 2020; 119:4123-4134. [PMID: 33029718 DOI: 10.1007/s00436-020-06911-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 09/27/2020] [Indexed: 10/23/2022]
Abstract
Turdus philomelos is a common Western Palearctic thrush species of forests and agricultural landscapes, where it relies on the presence of hedgerows, patches of trees, and shrubs. In the present study, we address long-term changes in component communities of trematodes in T. philomelos across the timespan of over half a century. Based on our preliminary observations, we hypothesized that component communities of trematodes in T. philomelos in the study area are more diverse and species-rich compared with several decades ago. In the 1961-2019, we performed full-body necropsies of T. philomelos, which originated from the southern Czech Republic, and examined them for the presence of trematodes. We compared the trematode species richness and diversity of the analyzed component communities. The number of trematode species per host steadily increased in time in adult females and males. In juveniles, the highest numbers of trematode species per host were reached already in 1961-1990, then dropped and slowly raised up again in the latter time periods. The newly accumulated evidence suggests that trematodes with intermediate hosts previously restricted to T. philomelos wintering grounds increased in abundance in the study area. Some of them (Morishitium polonicum, Psilotornus confertus) sporadically appeared in juveniles or first-year birds, from which they were previously completely absent. Some of the spreading species, such as Lutztrema attenuatum, are present in high prevalence and high intensities of infection. Yet unknown part of observed changes could be related to changes in food composition; however, direct evidence for changes in T. philomelos diet is lacking despite clear evidence for a decline in earthworms in agricultural landscapes.
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29
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Williams MA, Holland CV, Donohue I. Warming can alter host behavior in a similar manner to infection with behavior-manipulating parasites. Oecologia 2020; 194:65-74. [PMID: 32876762 DOI: 10.1007/s00442-020-04745-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 08/26/2020] [Indexed: 11/29/2022]
Abstract
Parasites are ecologically ubiquitous and, by modifying the physiology and behavior of their host organisms, act as key regulators of the dynamics and stability of ecosystems. It is, however, as yet unclear how parasitic relationships will act to moderate or accelerate the ecological impacts of global climate change. Here, we explore experimentally how the effects of parasites on both the physiology and behavior of their hosts can be moderated by warming, utilising a well-established aquatic host-parasite model system-the ecologically important amphipod Gammarus duebeni and its acanthocephalan parasite Polymorphus minutus. We show that, while only warming affected measured components of host physiology, parasite infection and warming both supressed predator-avoidance behavior of the host independently, yet in a similar manner. Six degrees of warming altered geotactic behaviors to the same extent as infection with behavior-manipulating parasites. These results indicate a novel mechanism by which parasites impact their ecosystems that could be critical to predicting the ecological impacts of warming. Our findings highlight the need for holistic knowledge of interaction networks, incorporating multiple interaction types and behaviors, to predict the effects of both warming and parasitism on the dynamics and stability of ecosystems.
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Affiliation(s)
- Maureen A Williams
- Department of Zoology, School of Natural Sciences, Trinity College Dublin, Dublin, Dublin 2, Ireland. .,School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, USA.
| | - Celia V Holland
- Department of Zoology, School of Natural Sciences, Trinity College Dublin, Dublin, Dublin 2, Ireland
| | - Ian Donohue
- Department of Zoology, School of Natural Sciences, Trinity College Dublin, Dublin, Dublin 2, Ireland
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30
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Meguro N, Kishida O, Utsumi S, Niwa S, Igarashi S, Kozuka C, Naniwa A, Sato T. Host phenologies and the life history of horsehair worms (Nematomorpha, Gordiida) in a mountain stream in northern Japan. Ecol Res 2020. [DOI: 10.1111/1440-1703.12122] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Nanoko Meguro
- Department of Biology, Graduate School of Science Kobe University Kobe Japan
| | - Osamu Kishida
- Tomakomai Experimental Forest, Field Science Center for Northern Biosphere Hokkaido University Tomakomai Japan
| | - Shunsuke Utsumi
- Uryu Experimental Forest, Field Science Center for Northern Biosphere Hokkaido University Horokanai Japan
| | - Shigeru Niwa
- Tomakomai Experimental Forest, Japan Wildlife Research Center Hokkaido University Tomakomai Japan
| | - Susumu Igarashi
- Tomakomai Experimental Forest, Field Science Center for Northern Biosphere Hokkaido University Tomakomai Japan
| | - Chikara Kozuka
- Uryu Experimental Forest, Field Science Center for Northern Biosphere Hokkaido University Horokanai Japan
| | - Aiko Naniwa
- Uryu Experimental Forest, Field Science Center for Northern Biosphere Hokkaido University Horokanai Japan
| | - Takuya Sato
- Department of Biology, Graduate School of Science Kobe University Kobe Japan
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31
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Sitko J, Heneberg P. Systemic collapse of a host-parasite trematode network associated with wetland birds in Europe. Parasitol Res 2020; 119:935-945. [PMID: 32088756 DOI: 10.1007/s00436-020-06624-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 02/07/2020] [Indexed: 12/31/2022]
Abstract
As host community diversity decreases, parasite diversity may also decline. The life cycles of trematodes involve multiple hosts from different orders, with many trematodes displaying narrow host specialization. In the 1960s and 2010s, we performed full-body necropsies of juvenile or first-year birds of four wetland bird species, Anas platyrhynchos, Aythya fuligula, Fulica atra, and Chroicocephalus ridibundus which originated from the southern Czech Republic, and examined them for the presence of trematodes. We compared the trematode species richness and diversity of the analyzed component communities. We found complete disintegration of host-parasite networks, which led to declining populations and local extinctions of the majority of trematode species, particularly those with narrow host preferences. For example, in black-headed gulls, 67% of trematode species recorded in the 1960s were absent in gulls that were examined in the 2010s. In contrast, we did not identify any trematode species that were absent in the 1960s but present in the 2010s. This collapse provides new insight into the recent debate regarding whether human-caused extinctions should be considered a problem when locally extinct host species are replaced by an equal or even higher number of nonnative species, thus maintaining local alpha diversities but leading to biotic homogenization and consequently reducing beta diversity. By documenting the collapse of the host-parasite network, we provide a strong argument that biodiversity cannot be assessed by simple measures alone, as only local-scale conservation measures allow the preservation of host-pathogen interactions and nutrient cycles and thus prevent the loss of low-visibility species, such as helminths.
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Affiliation(s)
- Jiljí Sitko
- Comenius Museum, Moravian Ornithological Station, Přerov, Czech Republic
| | - Petr Heneberg
- Third Faculty of Medicine, Charles University, Ruská 87, CZ-100 00, Prague, Czech Republic.
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32
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Benbow ME, Receveur JP, Lamberti GA. Death and Decomposition in Aquatic Ecosystems. Front Ecol Evol 2020. [DOI: 10.3389/fevo.2020.00017] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
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33
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Civitello DJ, Baker LH, Maduraiveeran S, Hartman RB. Resource fluctuations inhibit the reproduction and virulence of the human parasite Schistosoma mansoni in its snail intermediate host. Proc Biol Sci 2020; 287:20192446. [PMID: 31964301 DOI: 10.1098/rspb.2019.2446] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Resource availability can powerfully influence host-parasite interactions. However, we currently lack a mechanistic framework to predict how resource fluctuations alter individual infection dynamics. We address this gap with experiments manipulating resource supply and starvation for a human parasite, Schistosoma mansoni, and its snail intermediate host to test a hypothesis derived from mechanistic energy budget theory: resource fluctuations should reduce schistosome reproduction and virulence by inhibiting parasite ingestion of host biomass. Low resource supply caused hosts to remain small, reproduce less and produce fewer human-infectious cercariae. Periodic starvation also inhibited cercarial production and prevented infection-induced castration. The periodic starvation experiment also revealed substantial differences in fit between two bioenergetic model variants, which differ in their representation of host starvation. Simulations using the best-fit parameters of the winning model suggest that schistosome performance substantially declines with resource fluctuations with periods greater than 7 days. These experiments strengthen mechanistic theory, which can be readily scaled up to the population level to understand key feedbacks between resources, host population dynamics, parasitism and control interventions. Integrating resources with other environmental drivers of disease in an explicit bioenergetic framework could ultimately yield mechanistic predictions for many disease systems.
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Affiliation(s)
- David J Civitello
- Department of Biology, Emory University, 1510 Clifton Rd NE, Atlanta, GA 30322, USA
| | - Lucy H Baker
- Department of Biology, Emory University, 1510 Clifton Rd NE, Atlanta, GA 30322, USA
| | | | - Rachel B Hartman
- Department of Biology, Emory University, 1510 Clifton Rd NE, Atlanta, GA 30322, USA
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34
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Naman SM, Ueda R, Sato T. Predation risk and resource abundance mediate foraging behaviour and intraspecific resource partitioning among consumers in dominance hierarchies. OIKOS 2019. [DOI: 10.1111/oik.05954] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Sean M. Naman
- Dept of Zoology, Univ. of British Columbia BC Canada
- Present address: Dept of Geography, Univ. of British Columbia Canada
| | - Rui Ueda
- Dept of Biology, Graduate School of Sciences, Kobe Univ Kobe Japan
| | - Takuya Sato
- Dept of Biology, Graduate School of Sciences, Kobe Univ Kobe Japan
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35
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Sato T, Iritani R, Sakura M. Host manipulation by parasites as a cryptic driver of energy flow through food webs. CURRENT OPINION IN INSECT SCIENCE 2019; 33:69-76. [PMID: 31358198 DOI: 10.1016/j.cois.2019.02.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 02/25/2019] [Accepted: 02/27/2019] [Indexed: 06/10/2023]
Abstract
Manipulative parasites alter predator-prey interactions, and thus may facilitate, shift or create energy flow pathways through food webs (referred to hereafter as manipulation-mediated energy flow, MMEF). The ecological significance of MMEF would be determined not only by the strength of host manipulation, but also ecological and epidemiological factors, including host biomass, parasite incidence, and trophic position of the host-parasite association in their food webs. While previous theory has predicted that strong manipulation will destabilize host-parasite dynamics, a recently proposed theoretical framework claims that a switching strategy (sequential manipulation from predation suppression to enhancement) should allow parasites to induce strong predation enhancement and thus large MMEF. We formally outline the current and future directions to better understand the causes and consequences of MMEF across biological hierarchies.
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Affiliation(s)
- Takuya Sato
- Department of Biology, Graduate School of Sciences, Kobe University, Japan.
| | - Ryosuke Iritani
- Biosciences, College of Life and Environmental Science, University of Exeter, Cornwall Campus, Penryn, Cornwall TR10 9EZ, United Kingdom; Department of Integrative Biology, University of California, Berkeley, CA 94720, United States
| | - Midori Sakura
- Department of Biology, Graduate School of Sciences, Kobe University, Japan
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36
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McInturf AG, Pollack L, Yang LH, Spiegel O. Vectors with autonomy: what distinguishes animal‐mediated nutrient transport from abiotic vectors? Biol Rev Camb Philos Soc 2019; 94:1761-1773. [DOI: 10.1111/brv.12525] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 05/07/2019] [Accepted: 05/08/2019] [Indexed: 11/29/2022]
Affiliation(s)
- Alexandra G. McInturf
- Department of Wildlife, Fish, and Conservation Biology University of California One Shields Avenue, Davis, CA 95616 U.S.A
| | - Lea Pollack
- Department of Environmental Science and Policy University of California One Shields Avenue, Davis, CA 95616 U.S.A
| | - Louie H. Yang
- Department of Entomology and Nematology University of California, Davis One Shields Avenue, Davis, CA, 95616 U.S.A
| | - Orr Spiegel
- School of Zoology, Faculty of Life Sciences Sherman Building, Tel Aviv University Tel Aviv, 69978 Israel
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37
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Yan J, Cui B, Huang H, O'Flynn S, Bai J, Ysebaert T. Functional consumers regulate the effect of availability of subsidy on trophic cascades in the Yellow River Delta, China. MARINE POLLUTION BULLETIN 2019; 140:157-164. [PMID: 30803629 DOI: 10.1016/j.marpolbul.2019.01.045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 01/22/2019] [Accepted: 01/22/2019] [Indexed: 06/09/2023]
Abstract
Understanding the environmental context where heterogeneous ecological processes affect biotic interactions is a key aim of ecological research. However, mechanisms underlying spatial variation in trophic interactions linked to resource availability across ecosystem gradients remains unclear. We experimentally manipulated the interactive effects of predator fish and quantitative gradient of leaf detritus on macroinvertebrates and benthic algae. We found that non-linear changes in the strength of trophic cascades were strongly linked to the retention rates of experimental leaf detritus and also determined by predatory consumers. Retention rate of leaf detritus influenced the recruitment of predatory invertebrates and foraging preference of predators, accounting for largely the variations in shift of strengthening and weakening trophic cascades. Our results highlight the importance to identify joint processes of recruitment and foraging responses of functional consumer in understanding the impacts of both anthropogenic and natural alterations in subsidy on trophic interaction of coastal food webs.
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Affiliation(s)
- Jiaguo Yan
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China; NIOZ Royal Netherlands Institute for Sea Research, Department of Estuarine and Delta Systems, and Utrecht University, P.O. Box 140, 4400 AC Yerseke, the Netherlands
| | - Baoshan Cui
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China.
| | - Honghui Huang
- Guangdong Provincial Key Laboratory of Fishery Ecology and Environment, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, China
| | - Sarah O'Flynn
- NIOZ Royal Netherlands Institute for Sea Research, Department of Estuarine and Delta Systems, and Utrecht University, P.O. Box 140, 4400 AC Yerseke, the Netherlands
| | - Junhong Bai
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Tom Ysebaert
- NIOZ Royal Netherlands Institute for Sea Research, Department of Estuarine and Delta Systems, and Utrecht University, P.O. Box 140, 4400 AC Yerseke, the Netherlands
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38
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Iritani R, Sato T. Host-Manipulation by Trophically Transmitted Parasites: The Switcher-Paradigm. Trends Parasitol 2018; 34:934-944. [DOI: 10.1016/j.pt.2018.08.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Revised: 08/06/2018] [Accepted: 08/08/2018] [Indexed: 01/09/2023]
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39
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Waki T, Hino A, Umeda K. Angiostoma namekuji n. sp. (Nematoda: Angiostomatidae) from terrestrial slugs on Oshiba Island in the Seto Inland Sea, Japan. Syst Parasitol 2018; 95:913-920. [PMID: 30324417 DOI: 10.1007/s11230-018-9824-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2017] [Accepted: 09/18/2018] [Indexed: 11/26/2022]
Abstract
A new species of nematode, Angiostoma namekuji n. sp. (Angiostomatidae: Rhabditida), is described from the intestinal lumen of the terrestrial slug Philomycidae gen. sp. collected from Oshiba Island in the Seto Inland Sea, Hiroshima Prefecture, Japan. The new species is recognized by the following characteristics: body length 2,782-3,599 (mean 3,240) μm (male); 4,666-5,532 (5,030) μm (female); lateral field present; pharyngeal corpus with valves in the bulb; male with short tail, c = 35-57 (48), with one denticle; and seven pairs of genital papillae arranged as 1+2/3+1; female with tail having small denticles on distal tip; uterus c.50% of the body size; each ovary long, starting near vulva, not coiled, reflexed and reaching uterus; ovaries not crossing each other. Our phylogenetic tree based on sequences of the nuclear 28S ribosomal RNA gene supported the generic allocation of the new species in Angiostoma Dujardin, 1845.
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Affiliation(s)
- Tsukasa Waki
- Meguro Parasitological Museum, 4-1-1, Shimomeguro, Meguro-ku, Tokyo, 153-0064, Japan.
| | - Akina Hino
- Department of Environmental Parasitology, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Kousuke Umeda
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Nishi-2-13, Inada-cho, Obihiro, Hokkaido, 080-8555, Japan
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40
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Parasite transmission between trophic levels stabilizes predator-prey interaction. Sci Rep 2018; 8:12246. [PMID: 30115952 PMCID: PMC6095923 DOI: 10.1038/s41598-018-30818-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 08/06/2018] [Indexed: 11/29/2022] Open
Abstract
Manipulative parasites that promote their transmission by altering their host’s phenotype are widespread in nature, which suggests that host manipulation allows the permanent coexistence of the host with the parasite. However, the underlying mechanism by which host manipulation affects community stability remains unelucidated. Here, using a mathematical model, we show that host manipulation can stabilise community dynamics. We consider systems wherein parasites are transmitted between different trophic levels: intermediate host prey and final host predator. Without host manipulation, the non-manipulative parasite can destabilise an otherwise globally stable prey–predator system, causing population cycles. However, host manipulation can dampen such population cycles, particularly when the manipulation is strong. This finding suggests that host manipulation is a consequence of self-organized behavior of the parasite populations that allows permanent coexistence with the hosts and plays a key role in community stability.
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41
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Suetsugu K. Seed dispersal in the mycoheterotrophic orchid Yoania japonica: Further evidence for endozoochory by camel crickets. PLANT BIOLOGY (STUTTGART, GERMANY) 2018; 20:707-712. [PMID: 29656468 DOI: 10.1111/plb.12731] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 04/04/2018] [Indexed: 05/26/2023]
Abstract
Although orthopterans are rarely considered to be effective seed dispersal agents, the large flightless crickets known as 'weta' have been suggested to function as ecological replacements for small mammals in New Zealand, where such mammals are absent. In addition, a recent study reported that camel crickets mediate seed dispersal of several heterotrophic plants, including Yoania amagiensis in Japan. I investigated the seed dispersal mechanism of Yoania japonica because the fruit morphology is similar to Y. amagiensis. Specifically, I aimed to determine whether Y. japonica fruits are consumed by camel crickets and, if so, whether the seeds defecated by camel crickets remains intact, by checking seed viability with TTC staining, and whether germination rate is different between seeds collected directly from fruits and defecated seeds by comparing in situ seed germinability. The present study provides evidence that camel crickets function as seed dispersal agents of Y. japonica. Camel crickets were important consumers of Y. japonica fruits, and a substantial portion of the consumed seeds remained viable after passing through the digestive tract. In situ seed germination experiments revealed that the seeds defecated by camel crickets actually germinated in the field. In addition, the germination rate of defecated seeds was even higher than that of intact seeds, although the difference was not significant. Taken together with recent reports of insect-mediated endozoochory, such a seed dispersal system may be common in plants with fleshy indehiscent fruits and small seeds, even in locations where other seed dispersal agents are present.
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Affiliation(s)
- K Suetsugu
- Department of Biology, Graduate School of Science, Kobe University, Kobe, Japan
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42
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Loreto RG, Araújo JPM, Kepler RM, Fleming KR, Moreau CS, Hughes DP. Evidence for convergent evolution of host parasitic manipulation in response to environmental conditions. Evolution 2018; 72:2144-2155. [PMID: 29808578 DOI: 10.1111/evo.13489] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 03/09/2018] [Accepted: 03/27/2018] [Indexed: 01/19/2023]
Abstract
Environmental conditions exert strong selection on animal behavior. We tested the hypothesis that the altered behavior of hosts due to parasitic manipulation is also subject to selection imposed by changes in environmental conditions over time. Our model system is ants manipulated by parasitic fungi to bite onto vegetation. We analyzed the correlation between forest type (tropical vs. temperate) and the substrate where the host bites (biting substrate: leaf vs. twigs), the time required for the fungi to reach reproductive maturity, and the phylogenetic relationship among specimens from tropical and temperate forests from different parts of the globe. We show that fungal development in temperate forests is longer than the period of time leaves are present and the ants are manipulated to bite twigs. When biting twigs, 90% of the dead ants we examined had their legs wrapped around twigs, which appears to provide better attachment to the plant. Ancestral state character reconstruction suggests that leaf biting is the ancestral trait and that twig biting is a convergent trait in temperate regions of the globe. These three lines of evidence suggest that changes in environmental conditions have shaped the manipulative behavior of the host by its parasite.
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Affiliation(s)
- Raquel G Loreto
- Department of Entomology, Pennsylvania State University, University Park, Pennsylvania.,Center for Infectious Diseases Dynamics, Pennsylvania State University, University Park, Pennsylvania
| | - João P M Araújo
- Center for Infectious Diseases Dynamics, Pennsylvania State University, University Park, Pennsylvania.,Department of Biology, Pennsylvania State University, University Park, Pennsylvania
| | - Ryan M Kepler
- Sustainable Agricultural Systems Laboratory, United States Department of Agriculture, Beltsville, Maryland
| | - Kimberly R Fleming
- Department of Entomology, Pennsylvania State University, University Park, Pennsylvania
| | - Corrie S Moreau
- Department of Science and Education, Field Museum of Natural History, Chicago, Illinois
| | - David P Hughes
- Department of Entomology, Pennsylvania State University, University Park, Pennsylvania.,Center for Infectious Diseases Dynamics, Pennsylvania State University, University Park, Pennsylvania
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Naman SM, Rosenfeld JS, Kiffney PM, Richardson JS. The energetic consequences of habitat structure for forest stream salmonids. J Anim Ecol 2018; 87:1383-1394. [PMID: 29737519 DOI: 10.1111/1365-2656.12845] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 03/31/2018] [Indexed: 11/30/2022]
Abstract
Increasing habitat availability (i.e. habitat suitable for occupancy) is often assumed to elevate the abundance or production of mobile consumers; however, this relationship is often nonlinear (threshold or unimodal). Identifying the mechanisms underlying these nonlinearities is essential for predicting the ecological impacts of habitat change, yet the functional forms and ultimate causation of consumer-habitat relationships are often poorly understood. Nonlinear effects of habitat on animal abundance may manifest through physical constraints on foraging that restrict consumers from accessing their resources. Subsequent spatial incongruence between consumers and resources should lead to unimodal or saturating effects of habitat availability on consumer production if increasing the area of habitat suitable for consumer occupancy comes at the expense of habitats that generate resources. However, the shape of this relationship could be sensitive to cross-ecosystem prey subsidies, which may be unrelated to recipient habitat structure and result in more linear habitat effects on consumer production. We investigated habitat-production relationships for juveniles of stream-rearing Pacific salmon and trout (Oncorhynchus spp.), which typically forage in low-velocity pool habitats, while their prey (drifting benthic invertebrates) are produced upstream in high-velocity riffles. However, juvenile salmonids also consume subsidies of terrestrial invertebrates that may be independent of pool-riffle structure. We measured salmonid biomass production in 13 experimental enclosures each containing a downstream pool and upstream riffle, spanning a gradient of relative pool area (14%-80% pool). Increasing pool relative to riffle habitat area decreased prey abundance, leading to a nonlinear saturating effect on fish production. We then used bioenergetics model simulations to examine how the relationship between pool area and salmonid biomass is affected by varying levels of terrestrial subsidy. Simulations indicated that increasing terrestrial prey inputs linearized the effect of habitat availability on salmonid biomass, while decreasing terrestrial inputs exaggerated a "hump-shaped" effect. Our results imply that nonlinear effects of habitat availability on consumer production can arise from trade-offs between habitat suitable for consumer occupancy and habitat that generates prey. However, cross-ecosystem prey subsidies can effectively decouple this trade-off and modify consumer-habitat relationships in recipient systems.
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Affiliation(s)
- Sean M Naman
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada
| | - Jordan S Rosenfeld
- Applied Freshwater Ecology Research Unit, British Columbia Ministry of the Environment, Vancouver, BC, Canada
| | - Peter M Kiffney
- Fish Ecology Division, Watershed Program, National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Northwest Fisheries Science Center, Mukilteo, Washington
| | - John S Richardson
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, Canada
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Civitello DJ, Fatima H, Johnson LR, Nisbet RM, Rohr JR. Bioenergetic theory predicts infection dynamics of human schistosomes in intermediate host snails across ecological gradients. Ecol Lett 2018. [PMID: 29527787 DOI: 10.1111/ele.12937] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Epidemiological dynamics depend on the traits of hosts and parasites, but hosts and parasites are heterogeneous entities that exist in dynamic environments. Resource availability is a particularly dynamic and potent environmental driver of within-host infection dynamics (temporal patterns of growth, reproduction, parasite production and survival). We developed, parameterised and validated a model for resource-explicit infection dynamics by incorporating a parasitism module into dynamic energy budget theory. The model mechanistically explained the dynamic multivariate responses of the human parasite Schistosoma mansoni and its intermediate host snail to variation in resources and host density. At the population level, feedbacks mediated by resource competition could create a unimodal relationship between snail density and human risk of exposure to schistosomes. Consequently, weak snail control could backfire if reductions in snail density release remaining hosts from resource competition. If resource competition is strong and relevant to schistosome production in nature, it could inform control strategies.
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Affiliation(s)
- David J Civitello
- Department of Biology, Emory University, 1510 Clifton Rd NE, 30322, Atlanta, GA, USA
| | - Hiba Fatima
- Global Health Institute, Duke University, Durham, NC, USA
| | - Leah R Johnson
- Department of Statistics, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Roger M Nisbet
- Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, UCSB, 93106, Santa Barbara, CA, USA
| | - Jason R Rohr
- Department of Integrative Biology, University of South Florida, 4202, East Fowler Ave., 33620, Tampa, FL, USA
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Abstract
Insect behavior can be manipulated by parasites, and in many cases, such manipulation involves the central and peripheral nervous system. Neuroparasitology is an emerging branch of biology that deals with parasites that can control the nervous system of their host. The diversity of parasites that can manipulate insect behavior ranges from viruses to macroscopic worms and also includes other insects that have evolved to become parasites (notably, parasitic wasps). It is remarkable that the precise manipulation observed does not require direct entry into the insect brain and can even occur when the parasite is outside the body. We suggest that a spatial view of manipulation provides a holistic approach to examining such interactions. Integration across approaches from natural history to advanced imaging techniques, omics, and experiments will provide new vistas in neuroparasitology. We also suggest that for researchers interested in the proximate mechanisms of insect behaviors, studies of parasites that have evolved to control such behavior is of significant value.
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Affiliation(s)
- David P Hughes
- Department of Entomology, Pennsylvania State University, University Park, Pennsylvania 16802, USA;
- Department of Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Frederic Libersat
- Department of Life Sciences, Ben Gurion University, Beer Sheva 8410501, Israel;
- Zlotowski Center for Neurosciences, Ben Gurion University, Beer Sheva 8410501, Israel
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Suetsugu K. Independent recruitment of a novel seed dispersal system by camel crickets in achlorophyllous plants. THE NEW PHYTOLOGIST 2018; 217:828-835. [PMID: 29120037 DOI: 10.1111/nph.14859] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 09/23/2017] [Indexed: 05/26/2023]
Abstract
The seeds of most heterotrophic plants, commonly referred to as dust seeds, are typically dispersed in the air like dust particles. Therefore, little attention has been paid to how seeds of heterotrophic plants are dispersed, owing to the notion that wind dispersal is the dominant strategy. However, inconspicuous but fleshy, indehiscent fruit can be observed in distantly related plants that have independently evolved full heterotrophy. Here I investigated the seed dispersal system in three unrelated fully heterotrophic plants with fleshy, indehiscent fruits (Yoania amagiensis, Monotropastrum humile and Phacellanthus tubiflorus) by direct observation, a differential exclusion experiment of fruit feeders and investigation on seed viability through the digestive tract. The present study revealed that camel crickets are the major seed disperser in three achlorophyllous plants in the study population. This represents the first evidence of seed dispersal by camel crickets in any angiosperm species. These heterotrophic plants grow in the understorey of densely vegetated forests where wind is probably an ineffective seed dispersal agent. Life-history traits of the achlorophyllous plants associated with heterotrophic lifestyles, such as colonization of dark understorey habitats and dust seeds, could facilitate independent recruitment of the novel endozoochorous seed dispersal system by camel crickets.
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Affiliation(s)
- Kenji Suetsugu
- Department of Biology, Graduate School of Science, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe, 657-8501, Japan
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47
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Astakhov MV. Matter and energy input with terrestrial invertebrates into a forest stream ecosystem. RUSS J ECOL+ 2017. [DOI: 10.1134/s1067413617050010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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48
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Infectious Agents Trigger Trophic Cascades. Trends Ecol Evol 2017; 32:681-694. [DOI: 10.1016/j.tree.2017.06.009] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 05/30/2017] [Accepted: 06/20/2017] [Indexed: 12/17/2022]
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49
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Haque ME, Gomi T, Sakai M, Negishi JN. Developing a food web-based transfer factor of radiocesium for fish, whitespotted char (Salvelinus leucomaenis) in headwater streams. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2017; 172:191-200. [PMID: 28390308 DOI: 10.1016/j.jenvrad.2017.02.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 01/10/2017] [Accepted: 02/22/2017] [Indexed: 06/07/2023]
Abstract
We developed a food web-based transfer factor (TFweb) to study contaminant movements from multiple prey items to a predator based on the dietary contributions of prey items with their respective contamination levels. TFweb was used to evaluate the transfer of 137Cs into whitespotted char (Salvelinus leucomaenis) from the trophic structure of a stream-riparian ecosystem in headwater streams draining a Japanese cedar forest. We also examined the applicability of this method by comparing sites with different contamination levels but similar surrounding environments in Fukushima and Gunma. All samples were collected from August 2012 to May 2013. The dietary contributions from both aquatic and terrestrial prey items to whitespotted char were analyzed using stable carbon and nitrogen isotope ratios. 137Cs activity concentrations in char ranged from 704 to 6082 Bq kg-1-dry in Fukushima and from 193 to 618 Bq kg-1-dry in Gunma. Dominant prey taxa such as mayflies (Ephemera japonica), spider crickets (Rhaphidosphoridae gen. spp.), and freshwater crabs (Geothelphusa dehaani), each of them accounted for 3-12% of the fish diet, based on lower and upper estimates, respectively. TFweb ranged from 1.12 to 3.79 in Fukushima and from 1.30 to 4.30 in Gunma, which suggested bioaccumulation from prey items to predator. Widely used ecological parameters TFs by media-char and TTF by single prey-char showed high variability with both dilution and accumulation. TFweb is applicable for 137Cs transfer in predator-prey systems with complex food web structures of stream-riparian ecosystems.
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Affiliation(s)
- Md Enamul Haque
- Department of Symbiotic Science of Environment and Natural Resources, United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan; Department of Zoology, Faculty of Biological Sciences, Jahangirnagar University, Savar, Dhaka 1342, Bangladesh.
| | - Takashi Gomi
- Department of International Environmental and Agricultural Science, Faculty of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan
| | - Masaru Sakai
- Department of Integrated Science and Engineering for Sustainable Society, Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan
| | - Junjiro N Negishi
- Faculty of Environmental Earth Science, Hokkaido University, N10, W5, Kita-ku, Sapporo, Hokkaido 060-0860, Japan
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50
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Seasonal variation in food web-based transfer factors of radiocesium in white-spotted char (Salvelinus leucomaenis) from headwater streams. LANDSCAPE AND ECOLOGICAL ENGINEERING 2017. [DOI: 10.1007/s11355-016-0324-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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