19:I[42426,["/_next/static/immutable/chunks/1xctgzqre-wsy.js","/_next/static/immutable/chunks/06_-wz6pdtp2b.js","/_next/static/immutable/chunks/30e52g49hg40p.js","/_next/static/immutable/chunks/02yq6tul2z-oh.js","/_next/static/immutable/chunks/10bx_ec2vj7n_.js","/_next/static/immutable/chunks/33bfn03fo8xnt.js","/_next/static/immutable/chunks/0tfjf78scu61b.js","/_next/static/immutable/chunks/31xnvej4n1bi9.js"],"default"] 1a:T650,

Using an epibenthic sled, sampling was conducted at 25 stations along a transect from south of Cape Cod to near Bermuda and ranging in depth from 1000 to 5200m. After samples were brought on board, the mud was sieved (1mm mesh) using cold (2-3 degrees C) seawater and the bivalves and gastropods were picked from the samples, identified to genus or species and the first 20-30 individuals frozen (-80) in individual 1.5 ml tubes with any additional individuals placed in ethanol in a common station tube and then stored at -80. All other taxa were placed unsorted in 95% ethanol and are now stored at 4 degrees C. Because the initial sorting was done at sea under less than ideal conditions, the investigators resorted the samples under a microscope in the lab. So far, over 2600 protobranchs distributed among 27 species have been collected.

Sampling success was good, although somewhat sporadic, especially early in the cruise. The investigators used 2 different sleds - a heavy version with closing door and a lighter version where the doors remained open on ascent. The heavier sled was used for the first 12 samples. Because the collections from the heavier sled were less than expected (based on previous epibenthic sled samples of this area). the lighter sled was used for the remainder of the cruise. The lighter sled usually returned with much better samples, although this could also reflect the investigators' increased experience in sampling later in the cruise.

Samples are currently stored at UMass, but will be moved to the MCZ at Harvard for more permanent storage and curation.

1b:Td0e,In the early 1990s, we proposed the first explicit model of population differentiation and speciation in the deep-sea fauna, the depth-differentiation hypothesis (Etter and Rex 1991). According to this theory, the potential for population differentiation decreases with depth because the bathyal zone (200-4000 m) has stronger selective gradients and more opportunity for geographic isolation to impede gene flow than does the more environmentally uniform abyssal plain (>4000 m). To determine whether depth-related variation is genetic, and therefore a consequence of evolutionary change, we developed new methods to extract and sequence mitochondrial DNA from archived deep-sea molluscan species collected in earlier expeditions that had been fixed in formalin and preserved in alcohol. These genetic studies, summarized in Etter et al. (2005) and reviewed in this proposal, support the depth-differentiation hypothesis. More importantly, they have revealed the limitations of using preserved material, and have resulted in a much more specific research agenda for the future. Here we propose the first deep-sea sampling program specifically directed at answering fundamental evolutionary questions. We describe 3 hypotheses about evolution in the deep sea that emerged from our previous work. 1) The depth differentiation hypothesis suggesting population divergence decreases with depth. 2) The strong break in population structure at 3300 m may represent an unrecognized phylogeographic barrier. 3) Abyssal populations may be sinks that suffer chronic local extinction from being too rare to mate successfully, and are maintained by continued immigration from more abundant bathyal source populations. Our plan is to test each of these hypotheses using deep-sea protobranch bivalves, but for rigorous tests we need multiple independent loci. Nuclear loci are essential as independent measures of population structure, gene flow and historical influences, but are also critical to establish whether some of the remarkable divergences we have documented represent cryptic species. The formalin fixed tissues we have now are too degraded to obtain nuclear loci, so we are proposing to collect fresh samples to develop the nuclear loci (introns). The primary focus of this proposal (first three years of work) will be to collect the samples and develop nuclear markers from those samples that are sufficiently variable in deep-sea protobranchs to test each of the hypotheses and distinguish intra versus interspecific variation. The deep-sea supports one of the most diverse and unique marine communities, the evolutionary and historical development of which are virtually unknown. The proposed research will contribute very significantly to answering the two most basic question about evolutionary diversification in this vast environment: Where does it occur, and how? It will also create a solid conceptual and methodological context for future evolutionary studies in the deep sea. The source-sink hypothesis of abyssal biodiversity is the most synthetic and comprehensive explanation of large-scale patterns of species diversity in the deep ocean. If proven correct by the proposed study of population genetic structure, it will greatly simplify our understanding of both evolutionary and ecological causes of species diversity patterns.6:["$","$L19",null,{"dataset":{"_id":"542513","description":"

Protobranch bivalves collected in a series of epibenthic sled samples taken in the western North Atlantic from 1000-5200 m depth. The project investigators are only using the mollusks, all other taxa are unsorted, stored in 95% ethanol and available for others to use.

\n","problem":"","acquisition":"$1a","processing":"

BCO-DMO Processing Notes:
\n- transposed species columns to rows;
\n- converted lat and lon in degrees and decimal minutes to decimal degrees.
\n

\n","bcodmoProcessing":"","title":"Counts of Protobranch bivalves collected in a series of epibenthic sled samples taken on R/V Endeavor cruise EN447 in the Western North Atlantic (34-39N, 68-70W) in 2008 (ENAB project)","nickname":"ENAB 2008 Protobranchs","dataUrl":"","currentState":"Final no updates expected","currentStateId":"7","validated":true,"restricted":false,"version":"1","version_date":"2014-12-17T05:00:00.000Z","abstract":"This dataset includes counts of Protobranch bivalves collected in a series of epibenthic sled samples taken on R/V Endeavor cruise EN447 in the Western North Atlantic (34-39N, 68-70W) in 2008.","citation":"Etter, R. J., Rex, M. (2021) Counts of Protobranch bivalves collected in a series of epibenthic sled samples taken on R/V Endeavor cruise EN447 in the Western North Atlantic (34-39N, 68-70W) in 2008 (ENAB project). Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2014-12-17 [if applicable, indicate subset used]. doi:10.26008/1912/bco-dmo.542513.1 [access date]","citationParts":{"identifier":"doi:10.26008/1912/bco-dmo.542513.1","versionDate":"2014-12-17","versionId":"1","year":"2021","title":"Counts of Protobranch bivalves collected in a series of epibenthic sled samples taken on R/V Endeavor cruise EN447 in the Western North Atlantic (34-39N, 68-70W) in 2008 (ENAB project)","authors":"Etter, R. J., Rex, M.","publisher":"Biological and Chemical Oceanography Data Management Office (BCO-DMO)."},"doi":"10.26008/1912/bco-dmo.542513.1","release_date":null,"field_dataset_location":"","temporal_extent":{"start":"2008-06-04T04:00:00.000Z","end":"2008-06-21T04:00:00.000Z"},"temporal":{"resolution":"time:unitYear","type":"time:Interval","start":{"value":"1212552000","label":"2008"},"end":{"value":"1214020800","label":"2008"}},"spatial_extent":{"shape":"polygon","center":{"latitude":37.397435,"longitude":-69.6521},"wkt":"POLYGON ((-68.0762 34.915, -71.228 34.915, -71.228 39.87987, -68.0762 39.87987, -68.0762 34.915))","north":39.87987,"east":-68.0762,"south":34.915,"west":-71.228},"dataset_type":["Cruise Results"],"keywords":["biota","oceans"],"data_files":[{"id":"900368","title":"protobranchs.csv","url":"https://datadocs.bco-dmo.org/dataset/542513/file/0AAMn58i4qEOKl/protobranchs.csv","showTableUrl":"https://www.bco-dmo.org/dataset/542513/data/view/900368","description":"Primary data file for dataset ID 542513","filename":"protobranchs.csv","bytesize":35838,"checksum":{"value":"dd7e6c8e5c23e712575ea04135a6af7f","Algorithm":{"_id":"190","name":"MD5"}},"mimetype":"text/csv","fileType":{"_id":"192","name":"Comma Separated Values (.csv)"},"isErddap":"","date":"","isPublicDuringEmbargo":false,"primaryDataFile":true,"showTable":true,"restricted":false}],"supplemental_files":[],"roles":[{"role":{"_id":"138","name":"Principal Investigator"},"performedBy":{"_id":"51359","name":"Ron J. Etter"},"performedAtOrganization":{"_id":"249","name":"University of Massachusetts Boston"}},{"role":{"_id":"140","name":"Co-Principal Investigator"},"performedBy":{"_id":"51360","name":"Michael Rex"},"performedAtOrganization":{"_id":"249","name":"University of Massachusetts Boston"}},{"role":{"_id":"133","name":"Contact"},"performedBy":{"_id":"51359","name":"Ron J. Etter"},"performedAtOrganization":{"_id":"249","name":"University of Massachusetts Boston"}},{"role":{"_id":"145","name":"BCO-DMO Data Manager"},"performedBy":{"_id":"51498","name":"Shannon Rauch"},"performedAtOrganization":{"_id":"191","name":"Woods Hole Oceanographic Institution"}}],"deployments":[{"_id":"542217","name":"EN447","synonyms":[],"dates":{"start":"2008-06-04T00:00:00.000Z","end":"2008-06-21T00:00:00.000Z"},"platform":{"_id":"53992","name":"R/V Endeavor"},"chiefScientists":[{"id":"51359","name":"Ron J. Etter","role":"Chief Scientist"}]}],"funding":[{"_id":"54749","name":"OCE-0726382","fundingSource":{"_id":"355","name":"NSF Division of Ocean Sciences"},"url":"https://www.nsf.gov/awardsearch/show-award?AWD_ID=0726382"}],"instruments":[{"_id":"542522","name":"epibenthic sled","description":"Sampling was conducted using an epibenthic sled. 25 stations were sampled along a transect from south of Cape Cod to near Bermuda and ranging in depth from 1000 to 5200m","type_id":"542521","type_name":"Epibenthic Sled","type_desc":"An epibenthic sled is a semi-quantitative bottom-sampling device designed to trawl just above the bottom at the sediment water interface (the epibenthic zone). The sled consists of a rectangular steel frame with a mesh net (often more than one) attached to it. Towed along the ocean floor, its weight scrapes into the benthos, collecting any organisms on the surface or in the first few centimeters of sediment. It also collects the organisms in the water column just above the benthos.\r\n\r\nDescriptions from WHOI and Census of Marine Life.","type_acronym":""}],"parameters":[{"_id":"542524","name":"station","format":"","frictionlessType":"","description":"

Station number.

","units":{"_id":"","name":"unitless"},"type":{"_id":"987","name":"station","description":"

Station identifier; a unique number or alphanumeric string designating a general geographic location at which one or more sampling activities may occur.

"}},{"_id":"542525","name":"depth","format":"","frictionlessType":"","description":"

Sample depth.

","units":{"_id":"","name":"meters (m)"},"type":{"_id":"808","name":"depth","description":"

Observation/sample depth below the sea surface. Units often reported as: meters, feet.

\nWhen used in a JGOFS/GLOBEC dataset the depth is a best estimate; usually but not always calculated from pressure; calculated either from CTD pressure using Fofonoff and Millard (1982; UNESCO Tech Paper #44) algorithm adjusted for 1980 equation of state for seawater (EOS80) or simply equivalent to nominal depth as recorded during sampling if CTD pressure was unavailable.

"}},{"_id":"542526","name":"station_depth_total","format":"","frictionlessType":"","description":"

Total count of all individuals at that station/depth.

","units":{"_id":"","name":"unitless"},"type":{"_id":"1073","name":"no_bcodmo_term","description":"

An association with a community-wide standard parameter has not yet been made.

"}},{"_id":"542527","name":"species","format":"","frictionlessType":"","description":"

Name of the species.

","units":{"_id":"","name":"unitless"},"type":{"_id":"976","name":"species","description":"

a taxonomic binomial that consists of a genus name followed by the species name of an organism

"}},{"_id":"542528","name":"count","format":"","frictionlessType":"","description":"

Total count of individuals of the species at the station/depth.

","units":{"_id":"","name":"unitless"},"type":{"_id":"1079","name":"count","description":"

Number of items or individuals counted in sample or sample fraction

"}},{"_id":"542912","name":"lat","format":"","frictionlessType":"","description":"

Latitude of the sampling station.

","units":{"_id":"","name":"decimal degrees"},"type":{"_id":"730","name":"latitude","description":"

latitude, in decimal degrees, North is positive, negative denotes South; Reported in some datasets as degrees, minutes

"}},{"_id":"542913","name":"lon","format":"","frictionlessType":"","description":"

Longitude of the sampling station.

","units":{"_id":"","name":"decimal degrees"},"type":{"_id":"731","name":"longitude","description":"

longitude, in decimal degrees, East is positive, negative denotes West; Reported in some datsets as degrees, minutes

"}}],"related_publications":[],"related_datasets":[],"services":[{"grouping":"","items":[{"name":"View Data","description":"An in-browser view of the primary tabular data file","url":"https://www.bco-dmo.org/dataset/542513/data/view","contentType":"text/html","actionType":"view"}]},{"grouping":"Metadata","items":[{"name":"HTML","description":"A simple HTML page of the dataset metadata","url":"https://www.bco-dmo.org/dataset/542513/description","contentType":"text/html","actionType":"view"},{"name":"PDF","description":"A PDF of the HTML dataset metadata","url":"https://www.bco-dmo.org/dataset/542513/Dataset_description.pdf","contentType":"application/pdf","actionType":"download"},{"name":"ISO 19115-2 (NOAA Profile)","description":"","url":"https://www.bco-dmo.org/dataset/542513/iso","contentType":"application/xml","actionType":"download"}]}],"programs":[],"projects":[{"_id":"2161","name":"Evolution in the North Atlantic Basin","acronym":"ENAB","description":"$1b"}],"archives":[{"id_value":"10.26008/1912/bco-dmo.542513.1","url":"https://doi.org/10.26008/1912/bco-dmo.542513.1","date_assigned":"2021-12-28","version_date":"2014-12-17","archiver":"Marine Biological Laboratory/Woods Hole Oceanographic Institution Library (MBLWHOI DLA)","archiver_id":"272"}],"license":{"name":"Creative Commons Attribution 4.0","id":"CC-BY-4.0","uri":"https://creativecommons.org/licenses/by/4.0/","spdxUri":"https://spdx.org/licenses/CC-BY-4.0"},"metrics":{"views":{"count":74},"downloads":{"count":346}}}}]