Shank
Timothy M.
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Timothy M.
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ArticleBacterial diversity and successional patterns during biofilm formation on freshly exposed basalt surfaces at diffuse-flow deep-sea vents(Frontiers Media, 2015-09-10) Gulmann, Lara K. ; Beaulieu, Stace E. ; Shank, Timothy M. ; Ding, Kang ; Seyfried, William E. ; Sievert, Stefan M.Many deep-sea hydrothermal vent systems are regularly impacted by volcanic eruptions, leaving fresh basalt where abundant animal and microbial communities once thrived. After an eruption, microbial biofilms are often the first visible evidence of biotic re-colonization. The present study is the first to investigate microbial colonization of newly exposed basalt surfaces in the context of vent fluid chemistry over an extended period of time (4–293 days) by deploying basalt blocks within an established diffuse-flow vent at the 9°50′ N vent field on the East Pacific Rise. Additionally, samples obtained after a recent eruption at the same vent field allowed for comparison between experimental results and those from natural microbial re-colonization. Over 9 months, the community changed from being composed almost exclusively of Epsilonproteobacteria to a more diverse assemblage, corresponding with a potential expansion of metabolic capabilities. The process of biofilm formation appears to generate similar surface-associated communities within and across sites by selecting for a subset of fluid-associated microbes, via species sorting. Furthermore, the high incidence of shared operational taxonomic units over time and across different vent sites suggests that the microbial communities colonizing new surfaces at diffuse-flow vent sites might follow a predictable successional pattern.
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ArticleMid-ocean ridge exploration with an autonomous underwater vehicle(Oceanography Society, 2007-12) Yoerger, Dana R. ; Bradley, Albert M. ; Jakuba, Michael V. ; Tivey, Maurice A. ; German, Christopher R. ; Shank, Timothy M. ; Embley, Robert W.Human-occupied submersibles, towed vehicles, and tethered remotely operated vehicles (ROVs) have traditionally been used to study the deep seafloor. In recent years, however, autonomous underwater vehicles (AUVs) have begun to replace these other vehicles for mapping and survey missions. AUVs complement the capabilities of these pre-existing systems, offering superior mapping capabilities, improved logistics, and better utilization of the surface support vessel by allowing other tasks such as submersible operations, ROV work, CTD stations, or multibeam surveys to be performed while the AUV does its work. AUVs are particularly well suited to systematic preplanned surveys using sonars, in situ chemical sensors, and cameras in the rugged deep-sea terrain that has been the focus of numerous scientific expeditions (e.g., those to mid-ocean ridges and ocean margin settings). The Autonomous Benthic Explorer (ABE) is an example of an AUV that has been used for over 20 cruises sponsored by the National Science Foundation (NSF), the National Oceanic and Atmospheric Administration (NOAA) Office of Ocean Exploration (OE), and international and private sources. This paper summarizes NOAA OE-sponsored cruises made to date using ABE.
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ArticleChemistry, temperature, and faunal distributions at diffuse-flow hydrothermal vents : comparison of two geologically distinct ridge systems(The Oceanography Society, 2012-03) Luther, George W. ; Gartman, Amy ; Yucel, Mustafa ; Madison, Andrew S. ; Moore, Tommy S. ; Nees, Heather A. ; Nuzzio, Donald B. ; Sen, Arunima ; Lutz, Richard A. ; Shank, Timothy M. ; Fisher, Charles R.Diffuse-flow, low-temperature areas near hydrothermal vents support life via chemosynthesis: hydrogen sulfide (and other reduced chemical compounds) emanating from the subsurface is oxidized with bottom-water oxygen through bacterial mediation to fix carbon dioxide and produce biomass. This article reviews the in situ diffuse-flow chemistry (mainly H2S and O2) and temperature data collected in 2006 and 2009 along the Eastern Lau Spreading Center (ELSC), and from 2004 to 2008 at 9°N along the East Pacific Rise (9 N EPR), predominantly around macrofauna that contain endosymbionts at these two hydrothermal vent regions. More than 48,000 and 20,000 distinct chemical and temperature data points were collected with a multi-analyte electrochemical analyzer in the diffuse-flow waters at 9 N EPR and the ELSC, respectively. Despite their different geological settings and different macrofauna (two different species of snails and mussels at the ELSC versus two different species of tubeworms and mussels at 9 N EPR), there are similarities in the temperature and chemistry data, as well as in the distributions of organisms. The pattern of water chemistry preferred by the provannid snails (Alviniconcha spp., Ifremeria nautilei) and Bathymodiolus brevior at the ELSC is similar to the water chemistry pattern found for the siboglinid tubeworms (Tevnia jerichonana, Riftia pachyptila) and the Bathymodiolus thermophilus mussels at 9 N EPR. The eruptions at 9 N EPR in 2005 and 2006 resulted in increased H2S concentrations, increased H2S/T ratios, and an initial change in the dominant tubeworm species from Riftia pachyptila to Tevnia jerichonana after the eruption created new vent habitats. In 2005, two sites at 9 N EPR showed major increases in the H2S/T ratio from 2004, which suggested a probable eruption in this basalt-dominated system. At the ELSC, there was a decrease in the H2S/T ratio from northern to southern sites, which reflects the change in geological setting from basalt to andesite and the shallower water depths at the southern sites.
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ArticleSeamount sciences : quo vadis?(Oceanography Society, 2010-03) Staudigel, Hubert ; Koppers, Anthony A. P. ; Lavelle, J. William ; Pitcher, Tony J. ; Shank, Timothy M.Seamounts are fascinating natural ocean laboratories that inform us about fundamental planetary and ocean processes, ocean ecology and fisheries, and hazards and metal resources. The more than 100,000 large seamounts are a defining structure of global ocean topography and biogeography, and hundreds of thousands of smaller ones are distributed throughout every ocean on Earth.
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ArticleHigh-throughput sequencing and analysis of the gill tissue transcriptome from the deep-sea hydrothermal vent mussel Bathymodiolus azoricus(BioMed Central, 2010-10-11) Bettencourt, Raul ; Pinheiro, Miguel ; Egas, Conceicao ; Gomes, Paula ; Afonso, Mafalda ; Shank, Timothy M.Bathymodiolus azoricus is a deep-sea hydrothermal vent mussel found in association with large faunal communities living in chemosynthetic environments at the bottom of the sea floor near the Azores Islands. Investigation of the exceptional physiological reactions that vent mussels have adopted in their habitat, including responses to environmental microbes, remains a difficult challenge for deep-sea biologists. In an attempt to reveal genes potentially involved in the deep-sea mussel innate immunity we carried out a high-throughput sequence analysis of freshly collected B. azoricus transcriptome using gills tissues as the primary source of immune transcripts given its strategic role in filtering the surrounding waterborne potentially infectious microorganisms. Additionally, a substantial EST data set was produced and from which a comprehensive collection of genes coding for putative proteins was organized in a dedicated database, "DeepSeaVent" the first deep-sea vent animal transcriptome database based on the 454 pyrosequencing technology. A normalized cDNA library from gills tissue was sequenced in a full 454 GS-FLX run, producing 778,996 sequencing reads. Assembly of the high quality reads resulted in 75,407 contigs of which 3,071 were singletons. A total of 39,425 transcripts were conceptually translated into amino-sequences of which 22,023 matched known proteins in the NCBI non-redundant protein database, 15,839 revealed conserved protein domains through InterPro functional classification and 9,584 were assigned with Gene Ontology terms. Queries conducted within the database enabled the identification of genes putatively involved in immune and inflammatory reactions which had not been previously evidenced in the vent mussel. Their physical counterpart was confirmed by semi-quantitative quantitative Reverse-Transcription-Polymerase Chain Reactions (RT-PCR) and their RNA transcription level by quantitative PCR (qPCR) experiments. We have established the first tissue transcriptional analysis of a deep-sea hydrothermal vent animal and generated a searchable catalog of genes that provides a direct method of identifying and retrieving vast numbers of novel coding sequences which can be applied in gene expression profiling experiments from a non-conventional model organism. This provides the most comprehensive sequence resource for identifying novel genes currently available for a deep-sea vent organism, in particular, genes putatively involved in immune and inflammatory reactions in vent mussels. The characterization of the B. azoricus transcriptome will facilitate research into biological processes underlying physiological adaptations to hydrothermal vent environments and will provide a basis for expanding our understanding of genes putatively involved in adaptations processes during post-capture long term acclimatization experiments, at "sea-level" conditions, using B. azoricus as a model organism.
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ArticleSubmeter bathymetric mapping of volcanic and hydrothermal features on the East Pacific Rise crest at 9°50′N(American Geophysical Union, 2007-01-19) Ferrini, Vicki L. ; Fornari, Daniel J. ; Shank, Timothy M. ; Kinsey, James C. ; Tivey, Maurice A. ; Soule, Samuel A. ; Carbotte, Suzanne M. ; Whitcomb, Louis L. ; Yoerger, Dana R. ; Howland, Jonathan C.Recent advances in underwater vehicle navigation and sonar technology now permit detailed mapping of complex seafloor bathymetry found at mid-ocean ridge crests. Imagenex 881 (675 kHz) scanning sonar data collected during low-altitude (~5 m) surveys conducted with DSV Alvin were used to produce submeter resolution bathymetric maps of five hydrothermal vent areas at the East Pacific Rise (EPR) Ridge2000 Integrated Study Site (9°50′N, “bull's-eye”). Data were collected during 29 dives in 2004 and 2005 and were merged through a grid rectification technique to create high-resolution (0.5 m grid) composite maps. These are the first submeter bathymetric maps generated with a scanning sonar mounted on Alvin. The composite maps can be used to quantify the dimensions of meter-scale volcanic and hydrothermal features within the EPR axial summit trough (AST) including hydrothermal vent structures, lava pillars, collapse areas, the trough walls, and primary volcanic fissures. Existing Autonomous Benthic Explorer (ABE) bathymetry data (675 kHz scanning sonar) collected at this site provide the broader geologic context necessary to interpret the meter-scale features resolved in the composite maps. The grid rectification technique we employed can be used to optimize vehicle time by permitting the creation of high-resolution bathymetry maps from data collected during multiple, coordinated, short-duration surveys after primary dive objectives are met. This method can also be used to colocate future near-bottom sonar data sets within the high-resolution composite maps, enabling quantification of bathymetric changes associated with active volcanic, hydrothermal and tectonic processes.
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ArticleTemperature variations at diffuse and focused flow hydrothermal vent sites along the northern East Pacific Rise(American Geophysical Union, 2006-03-03) Scheirer, Daniel S. ; Shank, Timothy M. ; Fornari, Daniel J.In the decade following documented volcanic activity on the East Pacific Rise near 9°50′N, we monitored hydrothermal vent fluid temperature variations in conjunction with approximately yearly vent fluid sampling to better understand the processes and physical conditions that govern the evolution of seafloor hydrothermal systems. The temperature of both diffuse flow (low-temperature) and focused flow (high-temperature) vent fluids decreased significantly within several years of eruptions in 1991 and 1992. After mid-1994, focused flow vents generally exhibited periods of relatively stable, slowly varying temperatures, with occasional high- and low-temperature excursions lasting days to weeks. One such positive temperature excursion was associated with a crustal cracking event. Another with both positive and negative excursions demonstrated a subsurface connection between adjacent focused flow and diffuse flow vents. Diffuse flow vents exhibit much greater temperature variability than adjacent higher-temperature vents. On timescales of a week or less, temperatures at a given position within a diffuse flow field often varied by 5°–10°C, synchronous with near-bottom currents dominated by tidal and inertial forcing. On timescales of a week and longer, diffuse flow temperatures varied slowly and incoherently among different vent fields. At diffuse flow vent sites, the conceptual model of a thermal boundary layer immediately above the seafloor explains many of the temporal and spatial temperature variations observed within a single vent field. The thermal boundary layer is a lens of warm water injected from beneath the seafloor that is mixed and distended by lateral near-bottom currents. The volume of the boundary layer is delineated by the position of mature communities of sessile (e.g., tubeworms) and relatively slow-moving organisms (e.g., mussels). Vertical flow rates of hydrothermal fluids exiting the seafloor at diffuse vents are less than lateral flow rates of near-bottom currents (5–10 cm/s). The presence of a subsurface, shallow reservoir of warm hydrothermal fluids can explain differing temperature behaviors of adjacent diffuse flow and focused flow vents at 9°50′N. Different average temperatures and daily temperature ranges are explained by variable amounts of mixing of hydrothermal fluids with ambient seawater through subsurface conduits that have varying lateral permeability.
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DatasetSample log for HADESK bacterial biomarker phospholipid fatty acid content from sediment cores collected on R/V Thomas G. Thompson cruise TN309, May 2014(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-06-17) Shank, Timothy M. ; Drazen, Jeffrey C. ; Yancey, PaulThis dataset contains the sample log for HADESK bacterial biomarker phospholipid fatty acid (PLFA) content from sediment push cores. The same samples were also used for the organic matter (OM) analysis. Samples were taken in the Kermadec Trench in the Southwest Pacific, 4000 to ~10,000m from the RV/ Thomas G. Thompson during cruise TN309, May 2014. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/763873
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DatasetRaw counts of meiofauna identified in sediment samples from the Kermadec Trench in the Southwest Pacific, 4000 to ~10,000m from the RV/ Thomas G. Thompson during cruise TN309 (HADES-K), May 2014.(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-06-17) Shank, Timothy M. ; Drazen, Jeffrey C. ; Yancey, PaulThis dataset includes raw counts of meiofauna identified in push core samples taken in the Kermadec Trench in the Southwest Pacific, 4000 to ~10,000m from the RV/ Thomas G. Thompson during cruise TN309 (HADES-K), May 2014. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/763758
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DatasetRaw counts of macrofauna identified in sediment samples from the Kermadec Trench in the Southwest Pacific, 4000 to ~10,000m from the RV/ Thomas G. Thompson during cruise TN309 (HADES-K), May 2014.(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-06-17) Shank, Timothy M. ; Drazen, Jeffrey C. ; Yancey, PaulThis dataset includes raw counts of macrofauna families identified in push core samples taken in the Kermadec Trench in the Southwest Pacific, 4000 to ~10,000m from the RV/ Thomas G. Thompson during cruise TN309 (HADES-K), May 2014. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/763694
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ArticleNew England and Corner Rise seamounts(Oceanography Society, 2010-03) Shank, Timothy M.One of the longest seamount tracks in the Atlantic Ocean was formed by the Great Meteor or New England hotspot. This more than 3000-km-long hotspot track formed both the New England and Corner Rise seamounts, with a pause in volcanism 83 million years ago as evidenced by the morphological gap between chains.
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PreprintTesting the depth-differentiation hypothesis in a deepwater octocoral( 2015-03) Quattrini, Andrea M. ; Baums, Iliana B. ; Shank, Timothy M. ; Morrison, Cheryl L. ; Cordes, Erik E.The depth-differentiation hypothesis proposes that the bathyal region is a source of genetic diversity and an area where there is a high rate of species formation. Genetic differentiation should thus occur over relatively small vertical distances, particularly along the upper continental slope (200-1000 m) where oceanography varies greatly over small differences in depth. To test whether genetic differentiation within deepwater octocorals is greater over vertical rather than geographic distances, Callogorgia delta was targeted. This species commonly occurs throughout the northern Gulf of Mexico at depths ranging from 400-900 m. We found significant genetic differentiation (FST=0.042) across seven sites spanning 400 km of distance and 400 m of depth. A pattern of isolation by depth emerged, but geographic distance between sites may further limit gene flow. Water mass boundaries may serve to isolate populations across depth; however, adaptive divergence with depth is also a possible scenario. Microsatellite markers also revealed significant genetic differentiation (FST=0.434) between C. delta and a closely-related species, C. americana, demonstrating the utility of microsatellites in species delimitation of octocorals. Results provided support for the depth-differentiation hypothesis, strengthening the notion that factors co-varying with depth serve as isolation mechanisms in deep-sea populations.
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ArticleDeep-sea debris in the central and western Pacific Ocean(Frontiers Media, 2020-05-27) Amon, Diva ; Kennedy, Brian R. C. ; Cantwell, Kasey ; Suhre, Kelley ; Glickson, Deborah A. ; Shank, Timothy M. ; Rotjan, RandiMarine debris is a growing problem in the world’s deep ocean. The naturally slow biological and chemical processes operating at depth, coupled with the types of materials that are used commercially, suggest that debris is likely to persist in the deep ocean for long periods of time, ranging from hundreds to thousands of years. However, the realized scale of marine debris accumulation in the deep ocean is unknown due to the logistical, technological, and financial constraints related to deep-ocean exploration. Coordinated deep-water exploration from 2015 to 2017 enabled new insights into the status of deep-sea marine debris throughout the central and western Pacific Basin via ROV expeditions conducted onboard NOAA Ship Okeanos Explorer and RV Falkor. These expeditions included sites in United States protected areas and monuments, other Exclusive Economic Zones, international protected areas, and areas beyond national jurisdiction. Metal, glass, plastic, rubber, cloth, fishing gear, and other marine debris were encountered during 17.5% of the 188 dives from 150 to 6,000 m depth. Correlations were observed between deep-sea debris densities and depth, geological features, and distance from human-settled land. The highest densities occurred off American Samoa and the main Hawaiian Islands. Debris, mostly consisting of fishing gear and plastic, were also observed in most of the large-scale marine protected areas, adding to the growing body of evidence that even deep, remote areas of the ocean are not immune from human impacts. Interactions with and impacts on biological communities were noted, though further study is required to understand the full extent of these impacts. We also discuss potential sources and long-term implications of this debris.
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ArticleDefining the word “seamount”(Oceanography Society, 2010-03) Staudigel, Hubert ; Koppers, Anthony A. P. ; Lavelle, J. William ; Pitcher, Tony J. ; Shank, Timothy M.The term seamount has been defined many times (e.g., Menard, 1964; Wessel, 2001; Schmidt and Schmincke, 2000; Pitcher et al., 2007; International Hydrographic Organization, 2008; Wessel et al., 2010) but there is no “generally accepted” definition. Instead, most definitions serve the particular needs of a discipline or a specific paper.
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ArticleCharacterization of deep-sea benthic invertebrate megafauna of the Galapagos Islands(Nature Research, 2020-08-17) Salinas-de-León, Pelayo ; Martí-Puig, Patricia ; Buglass, Salome ; Arnés-Urgellés, Camila ; Rastoin-Laplane, Etienne ; Creemers, Marie ; Cairns, Stephen ; Fisher, Charles R. ; O’Hara, Timothy ; Ott, Bruce ; Raineault, Nicole A. ; Reiswig, Henry ; Rouse, Greg W. ; Rowley, Sonia ; Shank, Timothy M. ; Suarez, Jenifer ; Watling, Les ; Wicksten, Mary K. ; Marsh, LeighThe deep sea represents the largest and least explored biome on the planet. Despite the iconic status of the Galapagos Islands and being considered one of the most pristine locations on earth, the deep-sea benthic ecosystems of the archipelago are virtually unexplored in comparison to their shallow-water counterparts. In 2015, we embarked on a multi-disciplinary scientific expedition to conduct the first systematic characterization of deep-sea benthic invertebrate communities of the Galapagos, across a range of habitats. We explored seven sites to depths of over 3,300 m using a two-part Remotely Operated Vehicle (ROV) system aboard the E/V Nautilus, and collected 90 biological specimens that were preserved and sent to experts around the world for analysis. Of those, 30 taxa were determined to be undescribed and new to science, including members of five new genera (2 sponges and 3 cnidarians). We also systematically analysed image frame grabs from over 85 h of ROV footage to investigate patterns of species diversity and document the presence of a range of underwater communities between depths of 290 and 3,373 m, including cold-water coral communities, extensive glass sponge and octocoral gardens, and soft-sediment faunal communities. This characterization of Galapagos deep-sea benthic invertebrate megafauna across a range of ecosystems represents a first step to study future changes that may result from anthropogenic impacts to the planet’s climate and oceans, and informed the creation of fully protected deep-water areas in the Galapagos Marine Reserve that may help preserve these unique communities in our changing planet.
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ArticleThe Earth BioGenome Project 2020: starting the clock(National Academy of Sciences, 2022-01-18) Lewin, Harris A. ; Richards, Stephen ; Miguel L. Allende ; Lieberman Aiden, Erez ; Archibald, John M. ; Bálint, Miklós ; Barker, Katharine B. ; Baumgartner, Bridget ; Belov, Katherine ; Bertorelle, Giorgio ; Blaxter, Mark ; Cai, Jing ; Caperello, Nicolette D. ; Carlson, Keith ; Castilla-Rubio, Juan Carlos ; Chaw, Shu-Miaw ; Chen, Lei ; Childers, Anna K. ; Coddington, Jonathan ; Conde, Dalia A. ; Corominas, Montserrat ; Crandall, Keith A. ; Crawford, Andrew J. ; DiPalma, Federica ; Durbin, Richard ; Ebenezer, ThankGod E. ; Edwards, Scott V. ; Fedrigo, Olivier ; Flicek, Paul ; Formenti, Giulio ; Gibbs, Richard A. ; Gilbert, M. Thomas P. ; Goldstein, Melissa M. ; Graves, Jennifer Marshall ; Greely, Henry T. ; Grigoriev, Igor V. ; Hackett, Kevin J. ; Hall, Neil ; Haussler, David ; Helgen, Kristofer M. ; Hogg, Carolyn J. ; Isobe, Sachiko ; Jakobsen, Kjetill S. ; Janke, Axel ; Jarvis, Erich ; Johnson, Warren E. ; Jones, Steven J. M. ; Karlsson, Elinor K. ; Kersey, Paul J. ; Kim, Jin-Hyoung ; Kress, W. John ; Kuraku, Shigehiro ; Lawniczak, Mara K. N. ; Leebens-Mack, James H. ; Li, Xueyan ; Lindblad-Toh, Kerstin ; Liu, Xin ; Lopez, Jose V. ; Marques-Bonet, Tomas ; Mazard, Sophie ; Mazet, Jonna A. K. ; Mazzoni, Camila J. ; Myers, Eugene ; O’Neill, Rachel J. ; Paez, Sadye ; Park, Hyun ; Robinson, Gene E. ; Roquet, Cristina ; Ryder, Oliver A. ; Sabir, Jamal S. M. ; Shaffer, H. Bradley ; Shank, Timothy M. ; Sherkow, Jacob S. ; Soltis, Pamela S. ; Tang, Boping ; Tedersoo, Leho ; Uliano-Silva, Marcela ; Wang, Kun ; Wei, Xiaofeng ; Wetzer, Regina ; Wilson, Julia L. ; Xu, Xun ; Yang, Huanming ; Yoder, Anne D. ; Zhang, GuojieNovember 2020 marked 2 y since the launch of the Earth BioGenome Project (EBP), which aims to sequence all known eukaryotic species in a 10-y timeframe. Since then, significant progress has been made across all aspects of the EBP roadmap, as outlined in the 2018 article describing the project’s goals, strategies, and challenges (1). The launch phase has ended and the clock has started on reaching the EBP’s major milestones. This Special Feature explores the many facets of the EBP, including a review of progress, a description of major scientific goals, exemplar projects, ethical legal and social issues, and applications of biodiversity genomics. In this Introduction, we summarize the current status of the EBP, held virtually October 5 to 9, 2020, including recent updates through February 2021. References to the nine Perspective articles included in this Special Feature are cited to guide the reader toward deeper understanding of the goals and challenges facing the EBP.
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PreprintIncongruent patterns of genetic connectivity among four ophiuroid species with differing coral host specificity on North Atlantic seamounts( 2010-06) Cho, Walter W. ; Shank, Timothy M.Seamounts are considered to play a defining role in the evolution and diversity of marine fauna, acting as “stepping-stones” for dispersal, regional centers of genetic isolation and speciation, and refugia for deep-sea populations. This study focused on the patterns of dispersal and genetic connectivity of four seamount ophiuroid species (Asteroschema clavigera, Ophiocreas oedipus, Ophioplinthaca abyssalis and Ophioplinthaca chelys) displaying differing levels of associative (epifaunal) specificity to cold-water coral hosts inhabiting the New England and Corner Rise Seamount chains, and Muir Seamount in the Northwestern Atlantic. Analyses of mt16S and mtCOI revealed evidence for recent population expansion and high gene flow for all four species. However, species-specific genetic differentiation was significant based on seamount region and depth. Significant differences were found among regional seamount groups for A. clavigera, within seamount regions and seamounts for O. chelys, among 250 m depth intervals for A. clavigera, among 100 m depth intervals for O. oedipus, and there were indications of isolation by distance for A. clavigera and O. oedipus. In addition, A. clavigera and O. oedipus, broadcast spawners with high fidelity to specific coral hosts, displayed predominantly westward historical migration, while the ophioplinthacids, with lower host-specificity, displayed predominantly eastward migration. No congruent patterns of historical migration were evident among species and seamounts, yet these patterns can be correlated with species-specific host specificity, specific depth strata, and dispersal strategies. Conservation efforts to protect seamount ecosystems should promote multi-species approaches to genetic connectivity, and consider the impact of the “dependence” of biodiversity on host fauna in these vulnerable marine ecosystems.
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ArticleHydrothermal vent mussel habitat chemistry, pre- and post-eruption at 9°50′North on the East Pacific Rise(National Shellfisheries Association, 2008-03) Nees, Heather A. ; Moore, Tommy S. ; Mullaugh, Katherine M. ; Holyoke, Rebecca R. ; Janzen, Christopher P. ; Ma, Shufen ; Metzger, Edouard ; Waite, Tim J. ; Yucel, Mustafa ; Lutz, Richard A. ; Shank, Timothy M. ; Vetriani, Costantino ; Nuzzio, Donald B. ; Luther, George W.Between October 2005 and March 2006, a seafloor volcanic eruption occurred at 9°50′N East Pacific Rise (EPR), establishing a “time zero” for characterizing newly-formed hydrothermal vent habitats and comparing them to pre-eruption habitats. Before the eruption, mussels (Bathymodiolus thermophilus) formed large aggregates between 9°49.6′ and 9°50.3′N. After the eruption, the few mussels remaining were in sparsely-distributed individuals and clumps, seemingly transported via lava flows or from mass wasting of the walls of the axial trough. In situ voltammetry with solid state gold-amalgam microelectrodes was used to characterize the chemistry of vent fluids in mussel habitats from 2004 to 2007, providing data sets for comparison of oxygen, sulfide, and temperature. Posteruption fluids contained higher sulfide-to-temperature ratios (i.e., slopes of linear regressions) (10.86 μM °C−1) compared with pre-eruption values in 2004 and 2005 (2.79 μM °C−1 and −0.063 μM °C−1, respectively). These chemical differences can be attributed to the difference in geographic location in which mussels were living and physical factors arising from posteruptive fluid emissions.
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ArticleShipboard design and fabrication of custom 3D-printed soft robotic manipulators for the investigation of delicate deep-sea organisms(Public Library of Science, 2018-08-01) Vogt, Daniel M. ; Becker, Kaitlyn P. ; Phillips, Brennan T. ; Graule, Moritz A. ; Rotjan, Randi ; Shank, Timothy M. ; Cordes, Erik E. ; Wood, Robert J. ; Gruber, David F.Soft robotics is an emerging technology that has shown considerable promise in deep-sea marine biological applications. It is particularly useful in facilitating delicate interactions with fragile marine organisms. This study describes the shipboard design, 3D printing and integration of custom soft robotic manipulators for investigating and interacting with deep-sea organisms. Soft robotics manipulators were tested down to 2224m via a Remotely-Operated Vehicle (ROV) in the Phoenix Islands Protected Area (PIPA) and facilitated the study of a diverse suite of soft-bodied and fragile marine life. Instantaneous feedback from the ROV pilots and biologists allowed for rapid re-design, such as adding “fingernails”, and re-fabrication of soft manipulators at sea. These were then used to successfully grasp fragile deep-sea animals, such as goniasterids and holothurians, which have historically been difficult to collect undamaged via rigid mechanical arms and suction samplers. As scientific expeditions to remote parts of the world are costly and lengthy to plan, on-the-fly soft robot actuator printing offers a real-time solution to better understand and interact with delicate deep-sea environments, soft-bodied, brittle, and otherwise fragile organisms. This also offers a less invasive means of interacting with slow-growing deep marine organisms, some of which can be up to 18,000 years old.
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ArticleThe discovery of new deep-sea hydrothermal vent communities in the Southern Ocean and implications for biogeography(Public Library of Science, 2012-01-03) Rogers, Alex D. ; Tyler, Paul A. ; Connelly, Douglas P. ; Copley, Jonathan T. ; James, Rachael H. ; Larter, Robert D. ; Linse, Katrin ; Mills, Rachel A. ; Naveira Garabato, Alberto C. ; Pancost, Richard D. ; Pearce, David A. ; Polunin, Nicholas V. C. ; German, Christopher R. ; Shank, Timothy M. ; Boersch-Supan, Philipp H. ; Alker, Belinda J. ; Aquilina, Alfred ; Bennett, Sarah A. ; Clarke, Andrew ; Dinley, Robert J. J. ; Graham, Alastair G. C. ; Green, Darryl R. H. ; Hawkes, Jeffrey A. ; Hepburn, Laura ; Hilario, Ana ; Huvenne, Veerle A. I. ; Marsh, Leigh ; Ramirez-Llodra, Eva ; Reid, William D. K. ; Roterman, Christopher N. ; Sweeting, Christopher J. ; Thatje, Sven ; Zwirglmaier, KatrinSince the first discovery of deep-sea hydrothermal vents along the Galápagos Rift in 1977, numerous vent sites and endemic faunal assemblages have been found along mid-ocean ridges and back-arc basins at low to mid latitudes. These discoveries have suggested the existence of separate biogeographic provinces in the Atlantic and the North West Pacific, the existence of a province including the South West Pacific and Indian Ocean, and a separation of the North East Pacific, North East Pacific Rise, and South East Pacific Rise. The Southern Ocean is known to be a region of high deep-sea species diversity and centre of origin for the global deep-sea fauna. It has also been proposed as a gateway connecting hydrothermal vents in different oceans but is little explored because of extreme conditions. Since 2009 we have explored two segments of the East Scotia Ridge (ESR) in the Southern Ocean using a remotely operated vehicle. In each segment we located deep-sea hydrothermal vents hosting high-temperature black smokers up to 382.8°C and diffuse venting. The chemosynthetic ecosystems hosted by these vents are dominated by a new yeti crab (Kiwa n. sp.), stalked barnacles, limpets, peltospiroid gastropods, anemones, and a predatory sea star. Taxa abundant in vent ecosystems in other oceans, including polychaete worms (Siboglinidae), bathymodiolid mussels, and alvinocaridid shrimps, are absent from the ESR vents. These groups, except the Siboglinidae, possess planktotrophic larvae, rare in Antarctic marine invertebrates, suggesting that the environmental conditions of the Southern Ocean may act as a dispersal filter for vent taxa. Evidence from the distinctive fauna, the unique community structure, and multivariate analyses suggest that the Antarctic vent ecosystems represent a new vent biogeographic province. However, multivariate analyses of species present at the ESR and at other deep-sea hydrothermal vents globally indicate that vent biogeography is more complex than previously recognised.
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