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Liao L, Qin Q, Yi D, Lai Q, Cong B, Zhang H, Shao Z, Zhang J, Chen B. Evolution and adaptation of terrestrial plant-associated Plantibacter species into remote marine environments. Mol Ecol 2024; 33:e17385. [PMID: 38738821 DOI: 10.1111/mec.17385] [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: 10/10/2023] [Revised: 04/04/2024] [Accepted: 04/30/2024] [Indexed: 05/14/2024]
Abstract
Microbes are thought to be distributed and circulated around the world, but the connection between marine and terrestrial microbiomes remains largely unknown. We use Plantibacter, a representative genus associated with plants, as our research model to investigate the global distribution and adaptation of plant-related bacteria in plant-free environments, particularly in the remote Southern Ocean and the deep Atlantic Ocean. The marine isolates and their plant-associated relatives shared over 98% whole-genome average nucleotide identity (ANI), indicating recent divergence and ongoing speciation from plant-related niches to marine environments. Comparative genomics revealed that the marine strains acquired new genes via horizontal gene transfer from non-Plantibacter species and refined existing genes through positive selection to improve adaptation to new habitats. Meanwhile, marine strains retained the ability to interact with plants, such as modifying root system architecture and promoting germination. Furthermore, Plantibacter species were found to be widely distributed in marine environments, revealing an unrecognized phenomenon that plant-associated microbiomes have colonized the ocean, which could serve as a reservoir for plant growth-promoting microbes. This study demonstrates the presence of an active reservoir of terrestrial plant growth-promoting bacteria in remote marine systems and advances our understanding of the microbial connections between plant-associated and plant-free environments at the genome level.
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Affiliation(s)
- Li Liao
- Key Laboratory for Polar Science, Ministry of Natural Resources, Polar Research Institute of China, Shanghai, China
- School of Oceanography, Shanghai Jiao Tong University, Shanghai, China
| | - Qilong Qin
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Dian Yi
- Shanghai Center for Plant Stress Biology, CAS Center of Excellence in Molecular Plant Sciences, the Chinese Academy of Sciences, Shanghai, China
| | - Qiliang Lai
- Third Institute of Oceanography, Ministry of Natural Resources, P. R. China, Xiamen, China
| | - Bolin Cong
- First Institute of Oceanography, Ministry of Natural Resources, P. R. China, Qingdao, China
| | - Huiming Zhang
- Shanghai Center for Plant Stress Biology, CAS Center of Excellence in Molecular Plant Sciences, the Chinese Academy of Sciences, Shanghai, China
| | - Zongze Shao
- Third Institute of Oceanography, Ministry of Natural Resources, P. R. China, Xiamen, China
| | - Jin Zhang
- Key Laboratory for Polar Science, Ministry of Natural Resources, Polar Research Institute of China, Shanghai, China
| | - Bo Chen
- Key Laboratory for Polar Science, Ministry of Natural Resources, Polar Research Institute of China, Shanghai, China
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Schwob G, Cabrol L, Saucède T, Gérard K, Poulin E, Orlando J. Unveiling the co-phylogeny signal between plunderfish Harpagifer spp. and their gut microbiomes across the Southern Ocean. Microbiol Spectr 2024; 12:e0383023. [PMID: 38441978 PMCID: PMC10986581 DOI: 10.1128/spectrum.03830-23] [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: 11/01/2023] [Accepted: 02/09/2024] [Indexed: 03/07/2024] Open
Abstract
Understanding the factors that sculpt fish gut microbiome is challenging, especially in natural populations characterized by high environmental and host genomic complexity. However, closely related hosts are valuable models for deciphering the contribution of host evolutionary history to microbiome assembly, through the underscoring of phylosymbiosis and co-phylogeny patterns. Here, we propose that the recent diversification of several Harpagifer species across the Southern Ocean would allow the detection of robust phylogenetic congruence between the host and its microbiome. We characterized the gut mucosa microbiome of 77 individuals from four field-collected species of the plunderfish Harpagifer (Teleostei, Notothenioidei), distributed across three biogeographic regions of the Southern Ocean. We found that seawater physicochemical properties, host phylogeny, and geography collectively explained 35% of the variation in bacterial community composition in Harpagifer gut mucosa. The core microbiome of Harpagifer spp. gut mucosa was characterized by a low diversity, mostly driven by selective processes, and dominated by a single Aliivibrio Operational Taxonomic Unit (OTU) detected in more than 80% of the individuals. Nearly half of the core microbiome taxa, including Aliivibrio, harbored co-phylogeny signal at microdiversity resolution with host phylogeny, indicating an intimate symbiotic relationship and a shared evolutionary history with Harpagifer. The clear phylosymbiosis and co-phylogeny signals underscore the relevance of the Harpagifer model in understanding the role of fish evolutionary history in shaping the gut microbiome assembly. We propose that the recent diversification of Harpagifer may have led to the diversification of Aliivibrio, exhibiting patterns that mirror the host phylogeny. IMPORTANCE Although challenging to detect in wild populations, phylogenetic congruence between marine fish and its microbiome is critical, as it highlights intimate associations between hosts and ecologically relevant microbial symbionts. Our study leverages a natural system of closely related fish species in the Southern Ocean to unveil new insights into the contribution of host evolutionary trajectory on gut microbiome assembly, an underappreciated driver of the global marine fish holobiont. Notably, we unveiled striking evidence of co-diversification between Harpagifer and its microbiome, demonstrating both phylosymbiosis of gut bacterial communities and co-phylogeny of some specific bacterial symbionts, mirroring the host diversification patterns. Given Harpagifer's significance as a trophic resource in coastal areas and its vulnerability to climatic and anthropic pressures, understanding the potential evolutionary interdependence between the hosts and its microbiome provides valuable microbial candidates for future monitoring, as they may play a pivotal role in host species acclimatization to a rapidly changing environment.
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Affiliation(s)
- Guillaume Schwob
- Millennium Institute Biodiversity of Antarctic and Subantarctic Ecosystems (BASE), Santiago, Chile
- Department of Ecological Sciences, Faculty of Sciences, University of Chile, Santiago, Chile
- Institute of Ecology and Biodiversity, Santiago, Chile
| | - Léa Cabrol
- Millennium Institute Biodiversity of Antarctic and Subantarctic Ecosystems (BASE), Santiago, Chile
- Institute of Ecology and Biodiversity, Santiago, Chile
- Aix Marseille University, Univ Toulon, CNRS, IRD, Mediterranean Institute of Oceanography (MIO) UM 110, Marseille, France, Marseille, France
| | - Thomas Saucède
- UMR 6282 Biogeosciences, University Bourgogne Franche-Comté, CNRS, EPHE, Dijon, France
| | - Karin Gérard
- Millennium Institute Biodiversity of Antarctic and Subantarctic Ecosystems (BASE), Santiago, Chile
- Laboratory of Antarctic and Subantarctic Marine Ecosystems, Faculty of Sciences, University of Magallanes, Punta Arenas, Chile
- Cape Horn International Center, Puerto Williams, Chile
| | - Elie Poulin
- Millennium Institute Biodiversity of Antarctic and Subantarctic Ecosystems (BASE), Santiago, Chile
- Department of Ecological Sciences, Faculty of Sciences, University of Chile, Santiago, Chile
- Institute of Ecology and Biodiversity, Santiago, Chile
| | - Julieta Orlando
- Millennium Institute Biodiversity of Antarctic and Subantarctic Ecosystems (BASE), Santiago, Chile
- Department of Ecological Sciences, Faculty of Sciences, University of Chile, Santiago, Chile
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3
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Seppey CVW, Cabrol L, Thalasso F, Gandois L, Lavergne C, Martinez-Cruz K, Sepulveda-Jauregui A, Aguilar-Muñoz P, Astorga-España MS, Chamy R, Dellagnezze BM, Etchebehere C, Fochesatto GJ, Gerardo-Nieto O, Mansilla A, Murray A, Sweetlove M, Tananaev N, Teisserenc R, Tveit AT, Van de Putte A, Svenning MM, Barret M. Biogeography of microbial communities in high-latitude ecosystems: Contrasting drivers for methanogens, methanotrophs and global prokaryotes. Environ Microbiol 2023; 25:3364-3386. [PMID: 37897125 DOI: 10.1111/1462-2920.16526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Accepted: 10/02/2023] [Indexed: 10/29/2023]
Abstract
Methane-cycling is becoming more important in high-latitude ecosystems as global warming makes permafrost organic carbon increasingly available. We explored 387 samples from three high-latitudes regions (Siberia, Alaska and Patagonia) focusing on mineral/organic soils (wetlands, peatlands, forest), lake/pond sediment and water. Physicochemical, climatic and geographic variables were integrated with 16S rDNA amplicon sequences to determine the structure of the overall microbial communities and of specific methanogenic and methanotrophic guilds. Physicochemistry (especially pH) explained the largest proportion of variation in guild composition, confirming species sorting (i.e., environmental filtering) as a key mechanism in microbial assembly. Geographic distance impacted more strongly beta diversity for (i) methanogens and methanotrophs than the overall prokaryotes and, (ii) the sediment habitat, suggesting that dispersal limitation contributed to shape the communities of methane-cycling microorganisms. Bioindicator taxa characterising different ecological niches (i.e., specific combinations of geographic, climatic and physicochemical variables) were identified, highlighting the importance of Methanoregula as generalist methanogens. Methylocystis and Methylocapsa were key methanotrophs in low pH niches while Methylobacter and Methylomonadaceae in neutral environments. This work gives insight into the present and projected distribution of methane-cycling microbes at high latitudes under climate change predictions, which is crucial for constraining their impact on greenhouse gas budgets.
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Affiliation(s)
- Christophe V W Seppey
- Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Tromsø, Norway
- Institute of Environmental Science and Geography, University of Potsdam, Potsdam-Golm, Germany
| | - Léa Cabrol
- Aix-Marseille University, CNRS, IRD, Mediterranean Institute of Oceanography (MIO) UM 110, Marseille, France
- Millennium Institute Biodiversity of Antarctic and Subantarctic Ecosystems (BASE), Santiago, Chile
| | - Frederic Thalasso
- Centro de Investigacíon y de Estudios Avanzados del Instituto Politecnico Nacional (Cinvestav-IPN), Departamento de Biotecnología y Bioingeniería, México, Mexico
| | - Laure Gandois
- Laboratoire Écologie Fonctionnelle et Environnement, Université de Toulouse, CNRS, Toulouse, France
| | - Céline Lavergne
- HUB AMBIENTAL UPLA, Laboratory of Aquatic Environmental Research, Universidad de Playa Ancha, Valparaíso, Chile
- Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Karla Martinez-Cruz
- Departamento de Ciencias y Recursos Naturales, Universidad de Magallanes, Punta Arenas, Chile
- Environmental Physics Group, Limnological Institute, University of Konstanz, Konstanz, Germany
| | | | - Polette Aguilar-Muñoz
- HUB AMBIENTAL UPLA, Laboratory of Aquatic Environmental Research, Universidad de Playa Ancha, Valparaíso, Chile
- Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | | | - Rolando Chamy
- Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Bruna Martins Dellagnezze
- Microbial Ecology Laboratory, Department of Microbial Biochemistry and Genomic, Biological Research Institute "Clemente Estable", Montevideo, Uruguay
| | - Claudia Etchebehere
- Microbial Ecology Laboratory, Department of Microbial Biochemistry and Genomic, Biological Research Institute "Clemente Estable", Montevideo, Uruguay
| | - Gilberto J Fochesatto
- Department of Atmospheric Sciences, University of Alaska Fairbanks, Fairbanks, Alaska, USA
| | - Oscar Gerardo-Nieto
- Centro de Investigacíon y de Estudios Avanzados del Instituto Politecnico Nacional (Cinvestav-IPN), Departamento de Biotecnología y Bioingeniería, México, Mexico
| | - Andrés Mansilla
- Departamento de Ciencias y Recursos Naturales, Universidad de Magallanes, Punta Arenas, Chile
| | - Alison Murray
- Division of Earth and Ecosystem Sciences, Desert Research Institute, Reno, Nevada, USA
| | - Maxime Sweetlove
- Royal Belgian Institute for Natural Sciences, OD-Nature, Brussels, Belgium
| | - Nikita Tananaev
- Melnikov Permafrost Institute, Russian Academy of Sciences, Yakutsk, Russia
- Institute of Natural Sciences, North-Eastern Federal University, Yakutsk, Russia
| | - Roman Teisserenc
- Laboratoire Écologie Fonctionnelle et Environnement, Université de Toulouse, CNRS, Toulouse, France
| | - Alexander T Tveit
- Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Tromsø, Norway
| | - Anton Van de Putte
- Royal Belgian Institute for Natural Sciences, OD-Nature, Brussels, Belgium
| | - Mette M Svenning
- Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Tromsø, Norway
| | - Maialen Barret
- Laboratoire Écologie Fonctionnelle et Environnement, Université de Toulouse, CNRS, Toulouse, France
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Buschi E, Dell’Anno A, Tangherlini M, Stefanni S, Lo Martire M, Núñez-Pons L, Avila C, Corinaldesi C. Rhodobacteraceae dominate the core microbiome of the sea star Odontaster validus (Koehler, 1906) in two opposite geographical sectors of the Antarctic Ocean. Front Microbiol 2023; 14:1234725. [PMID: 37799611 PMCID: PMC10548270 DOI: 10.3389/fmicb.2023.1234725] [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: 06/05/2023] [Accepted: 08/29/2023] [Indexed: 10/07/2023] Open
Abstract
Microbiota plays essential roles in the health, physiology, and in adaptation of marine multi-cellular organisms to their environment. In Antarctica, marine organisms have a wide range of unique physiological functions and adaptive strategies, useful for coping with extremely cold conditions. However, the role of microbiota associated with Antarctic organisms in such adaptive strategies is underexplored. In the present study, we investigated the diversity and putative functions of the microbiome of the sea star Odontaster validus, one of the main keystone species of the Antarctic benthic ecosystems. We compared the whole-body bacterial microbiome of sea stars from different sites of the Antarctic Peninsula and Ross Sea, two areas located in two opposite geographical sectors of the Antarctic continent. The taxonomic composition of O. validus microbiomes changed both between and within the two Antarctic sectors, suggesting that environmental and biological factors acting both at large and local scales may influence microbiome diversity. Despite this, one bacterial family (Rhodobacteraceae) was shared among all sea star individuals from the two geographical sectors, representing up to 95% of the microbial core, and suggesting a key functional role of this taxon in holobiont metabolism and well-being. In addition, the genus Roseobacter belonging to this family was also present in the surrounding sediment, implying a potential horizontal acquisition of dominant bacterial core taxa via host-selection processes from the environment.
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Affiliation(s)
- Emanuela Buschi
- Department of Marine Biotechnology, Stazione Zoologica di Napoli “Anton Dohrn”, Fano Marine Centre, Fano, Italy
| | - Antonio Dell’Anno
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Michael Tangherlini
- Department of Research Infrastructures for Marine Biological Resources, Stazione Zoologica di Napoli “Anton Dohrn”, Fano Marine Centre, Fano, Italy
| | - Sergio Stefanni
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica di Napoli “Anton Dohrn”, Naples, Italy
| | - Marco Lo Martire
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Laura Núñez-Pons
- Department of Integrative Marine Ecology, Stazione Zoologica di Napoli “Anton Dohrn”, Naples, Italy
- NBFC, National Biodiversity Future Center, Palermo, Italy
| | - Conxita Avila
- Department of Evolutionary Biology, Ecology and Environmental Sciences, Faculty of Biology, University of Barcelona, Barcelona, Catalonia, Spain
- Institut de Recerca de la Biodiversitat, University of Barcelona, Barcelona, Catalonia, Spain
| | - Cinzia Corinaldesi
- Department of Materials, Environmental Sciences and Urban Planning, Polytechnic University of Marche, Ancona, Italy
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5
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Segovia NI, González-Wevar CA, Naretto J, Rosenfeld S, Brickle P, Hüne M, Bernal V, Haye PA, Poulin E. The right tool for the right question: contrasting biogeographic patterns in the notothenioid fish Harpagifer spp. along the Magellan Province. Proc Biol Sci 2022; 289:20212738. [PMID: 35382596 PMCID: PMC8984805 DOI: 10.1098/rspb.2021.2738] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Molecular-based analysis has become a fundamental tool to understand the role of Quaternary glacial episodes. In the Magellan Province in southern South America, ice covering during the last glacial maximum (20 ka) radically altered the landscape/seascape, speciation rates and distribution of species. For the notothenioid fishes of the genus Harpagifer, in the area are described two nominal species. Nevertheless, this genus recently colonized South America from Antarctica, providing a short time for speciation processes. Combining DNA sequences and genotyping-by-sequencing SNPs, we evaluated the role of Quaternary glaciations over the patterns of genetic structure in Harpagifer across its distribution in the Magellan Province. DNA sequences showed low phylogeographic structure, with shared and dominant haplotypes between nominal species, suggesting a single evolutionary unit. SNPs identified contrastingly two groups in Patagonia and a third well-differentiated group in the Falkland/Malvinas Islands with limited and asymmetric gene flow. Linking the information of different markers allowed us to infer the relevance of postglacial colonization mediated by the general oceanographic circulation patterns. Contrasting rough- and fine-scale genetic patterns highlights the relevance of combined methodologies for species delimitation, which, depending on the question to be addressed, allows discrimination among phylogeographic structure, discarding incipient speciation, and contemporary spatial differentiation processes.
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Affiliation(s)
- N I Segovia
- Departamento de Ciencias Ecológicas, Instituto Milenio de Ecología y Biodiversidad (IEB), Universidad de Chile. Las Palmeras 3425, Ñuñoa, Santiago, Chile.,Departamento de Biología Marina, Facultad de Ciencias del Mar, Universidad Católica del Norte, Larrondo 1281, Coquimbo, Chile.,Instituto Milenio en Socio-ecología Costera (SECOS), Coquimbo, Chile.,Instituto Milenio Biodiversidad de Ecosistemas Antárticos y subAntárticos (MI-BASE), Valdivia, Chile
| | - C A González-Wevar
- Departamento de Ciencias Ecológicas, Instituto Milenio de Ecología y Biodiversidad (IEB), Universidad de Chile. Las Palmeras 3425, Ñuñoa, Santiago, Chile.,Instituto Milenio Biodiversidad de Ecosistemas Antárticos y subAntárticos (MI-BASE), Valdivia, Chile.,Instituto de Ciencias Marinas y Limnológicas (ICML), Facultad de Ciencias, Universidad Austral de Chile, Casilla 567, Valdivia, Chile.,Centro de Investigación en Dinámicas de Ecosistemas de Altas Latitudes (Fondap IDEAL), Universidad Austral de Chile
| | - J Naretto
- Costa Humboldt, Puerto Varas, Los Lagos, Chile
| | - S Rosenfeld
- Departamento de Ciencias Ecológicas, Instituto Milenio de Ecología y Biodiversidad (IEB), Universidad de Chile. Las Palmeras 3425, Ñuñoa, Santiago, Chile.,Laboratorio de Ecosistemas Antárticos y sub-Antárticos, Universidad de Magallanes, Chile
| | - P Brickle
- South Atlantic Environmental Research Institute (SAERI), PO Box 609, Stanley Cottage, Port Stanley, Falkland Islands, UK
| | - M Hüne
- Departamento de Ciencias Ecológicas, Instituto Milenio de Ecología y Biodiversidad (IEB), Universidad de Chile. Las Palmeras 3425, Ñuñoa, Santiago, Chile.,Centro de Investigación para la Conservación de los Ecosistemas Australes (ICEA), Punta Arenas, Chile
| | - V Bernal
- Departamento de Ciencias Ecológicas, Instituto Milenio de Ecología y Biodiversidad (IEB), Universidad de Chile. Las Palmeras 3425, Ñuñoa, Santiago, Chile.,Instituto Milenio Biodiversidad de Ecosistemas Antárticos y subAntárticos (MI-BASE), Valdivia, Chile
| | - P A Haye
- Departamento de Biología Marina, Facultad de Ciencias del Mar, Universidad Católica del Norte, Larrondo 1281, Coquimbo, Chile.,Instituto Milenio en Socio-ecología Costera (SECOS), Coquimbo, Chile
| | - E Poulin
- Departamento de Ciencias Ecológicas, Instituto Milenio de Ecología y Biodiversidad (IEB), Universidad de Chile. Las Palmeras 3425, Ñuñoa, Santiago, Chile.,Instituto Milenio Biodiversidad de Ecosistemas Antárticos y subAntárticos (MI-BASE), Valdivia, Chile
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Gill JG, Hill-Spanik KM, Whittaker KA, Jones ML, Plante C. Sargasso Sea bacterioplankton community structure and drivers of variance as revealed by DNA metabarcoding analysis. PeerJ 2022; 10:e12835. [PMID: 35251777 PMCID: PMC8893026 DOI: 10.7717/peerj.12835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 01/04/2022] [Indexed: 01/10/2023] Open
Abstract
Marine microbes provide the backbone for pelagic ecosystems by cycling and fixing nutrients and establishing the base of food webs. Microbial communities are often assumed to be highly connected and genetically mixed, with localized environmental filters driving minor changes in structure. Our study applied high-throughput Illumina 16S ribosomal RNA gene amplicon sequencing on whole-community bacterial samples to characterize geographic, environmental, and stochastic drivers of community diversity. DNA was extracted from seawater collected from the surface (N = 18) and at depth just below the deep chlorophyll-a maximum (DCM mean depth = 115.4 m; N = 22) in the Sargasso Sea and adjacent oceanographic regions. Discrete bacterioplankton assemblages were observed at varying depths in the North Sargasso Sea, with a signal for distance-decay of bacterioplankton community similarity found only in surface waters. Bacterial communities from different oceanic regions could be distinguished statistically but exhibited a low magnitude of divergence. Redundancy analysis identified temperature as the key environmental variable correlated with community structuring. The effect of dispersal limitation was weak, while variation partitioning and neutral community modeling demonstrated stochastic processes influencing the communities. This study advances understanding of microbial biogeography in the pelagic ocean and highlights the use of high-throughput sequencing methods in studying microbial community structure.
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Affiliation(s)
- John Geoffrey Gill
- Grice Marine Laboratory, College of Charleston, Charleston, SC, United States
| | | | - Kerry A. Whittaker
- Sea Education Association, Woods Hole, MA, United States,Maine Maritime Academy, Castine, Maine, United States
| | - Martin L. Jones
- Department of Mathematics, College of Charleston, Charleston, SC, United States
| | - Craig Plante
- Grice Marine Laboratory, College of Charleston, Charleston, SC, United States
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