USAP-DC

{"dp_type": "Project", "free_text": "Bivalves"}

[{"awards": "1543031 Ivany, Linda", "bounds_geometry": null, "dataset_titles": "NetCDF outputs from middle Eocene climate simulation using the GENESIS global circulation model ; Organic carbon isotope data from serially sampled Eocene driftwood from the La Meseta Fm., Seymour ; Oxygen isotope data from serially sampled Eocene bivalves from the La Meseta Fm., Seymour Island, Antarctica ", "datasets": [{"dataset_uid": "601175", "doi": "10.15784/601175 ", "keywords": "Antarctica; Atmosphere; Climate Model; Computer Model; Eocene; Genesis; Global Circulation Model; Modeling; Model Output; Seasonality; Temperature", "people": "Judd, Emily", "repository": "USAP-DC", "science_program": null, "title": "NetCDF outputs from middle Eocene climate simulation using the GENESIS global circulation model ", "url": "https://www.usap-dc.org/view/dataset/601175"}, {"dataset_uid": "601173", "doi": "10.15784/601173 ", "keywords": "Antarctica; Carbon Isotopes; Driftwood; Eocene; Geochemistry; Geochronology; Isotope Data; La Meseta Formation; Mass Spectrometer; Mass Spectrometry; Organic Carbon Isotopes; Seasonality; Seymour Island; Wood", "people": "Judd, Emily", "repository": "USAP-DC", "science_program": null, "title": "Organic carbon isotope data from serially sampled Eocene driftwood from the La Meseta Fm., Seymour ", "url": "https://www.usap-dc.org/view/dataset/601173"}, {"dataset_uid": "601174", "doi": "10.15784/601174", "keywords": "Antarctica; Biota; Bivalves; Cucullaea; Eocene; Glaciers/ice Sheet; Glaciers/Ice Sheet; Isotope Data; La Meseta Formation; Mass Spectrometer; Mass Spectrometry; Oxygen Isotope; Paleotemperature; Retrotapes; Seasonality; Seymour Island", "people": "Judd, Emily", "repository": "USAP-DC", "science_program": null, "title": "Oxygen isotope data from serially sampled Eocene bivalves from the La Meseta Fm., Seymour Island, Antarctica ", "url": "https://www.usap-dc.org/view/dataset/601174"}], "date_created": "Tue, 23 Apr 2019 00:00:00 GMT", "description": "In order to understand what environmental conditions might look like for future generations, we need to turn to archives of past times when the world was indeed warmer, before anyone was around to commit them to collective memory. The geologic record of Earth\u0027s past offers a glimpse of what could be in store for the future. Research by Ivany and her team looks to Antarctica during a time of past global warmth to see how seasonality of temperature and rainfall in coastal settings are likely to change in the future. They will use the chemistry of fossils (a natural archive of these variables) to test a provocative hypothesis about near-monsoonal conditions in the high latitudes when the oceans are warm. If true, we can expect high-latitude shipping lanes to become more hazardous and fragile marine ecosystems adapted to constant cold temperatures to suffer. With growing information about how human activities are likely to affect the planet in the future, we will be able to make more informed decisions about policies today. This research involves an international team of scholars, including several women scientists, training of graduate students, and a public museum exhibit to educate children about how we study Earth\u0027s ancient climate and what we can learn from it.\u003cbr/\u003e\u003cbr/\u003eAntarctica is key to an understanding how Earth?s climate system works under conditions of elevated CO2. The poles are the most sensitive regions on the planet to climate change, and the equator-to-pole temperature gradient and the degree to which high-latitude warming is amplified are important components for climate models to capture. Accurate proxy data with good age control are therefore critical for testing numerical models and establishing global patterns. The La Meseta Formation on Seymour Island is the only documented marine section from the globally warm Eocene Epoch exposed in outcrop on the continent; hence its climate record is integral to studies of warming. Early data suggest the potential for strongly seasonal precipitation and runoff in coastal settings. This collaboration among paleontologists, geochemists, and climate modelers will test this using seasonally resolved del-18O data from fossil shallow marine bivalves to track the evolution of seasonality through the section, in combination with independent proxies for the composition of summer precipitation (leaf wax del-D) and local seawater (clumped isotopes). The impact of the anticipated salinity stratification on regional climate will be evaluated in the context of numerical climate model simulations. In addition to providing greater clarity on high-latitude conditions during this time of high CO2, the combination of proxy and model results will provide insights about how Eocene warmth may have been maintained and how subsequent cooling came about. As well, a new approach to the analysis of shell carbonates for 87Sr/86Sr will allow refinements in age control so as to allow correlation of this important section with other regions to clarify global climate gradients. The project outlined here will develop new and detailed paleoclimate records from existing samples using well-tuned as well as newer proxies applied here in novel ways. Seasonal extremes are climate parameters generally inaccessible to most studies but critical to an understanding of climate change; these are possible to resolve in this well-preserved, accretionary-macrofossil-bearing section. This is an integrated study that links marine and terrestrial climate records for a key region of the planet across the most significant climate transition in the Cenozoic.", "east": -56.0, "geometry": "POINT(-56.5 -64.25)", "instruments": "NOT APPLICABLE \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "is_usap_dc": true, "keywords": "PALEOCLIMATE RECONSTRUCTIONS; USAP-DC; ISOTOPES; NOT APPLICABLE; MACROFOSSILS; Antarctica", "locations": "Antarctica", "north": -64.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Ivany, Linda; Lu, Zunli; Junium, Christopher; Samson, Scott", "platforms": "OTHER \u003e NOT APPLICABLE \u003e NOT APPLICABLE", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.5, "title": "Seasonality, Summer Cooling, and Calibrating the Approach of the Icehouse in Late Eocene Antarctica", "uid": "p0010025", "west": -57.0}, {"awards": "1355533 Dayton, Paul", "bounds_geometry": "POLYGON((163 -78,163.4 -78,163.8 -78,164.2 -78,164.6 -78,165 -78,165.4 -78,165.8 -78,166.2 -78,166.6 -78,167 -78,167 -78.05,167 -78.1,167 -78.15,167 -78.2,167 -78.25,167 -78.3,167 -78.35,167 -78.4,167 -78.45,167 -78.5,166.6 -78.5,166.2 -78.5,165.8 -78.5,165.4 -78.5,165 -78.5,164.6 -78.5,164.2 -78.5,163.8 -78.5,163.4 -78.5,163 -78.5,163 -78.45,163 -78.4,163 -78.35,163 -78.3,163 -78.25,163 -78.2,163 -78.15,163 -78.1,163 -78.05,163 -78))", "dataset_titles": "A Multi-decadal Record of Antarctic Benthos: Image Analysis to Maximize Data Utilization", "datasets": [{"dataset_uid": "600164", "doi": "10.15784/600164", "keywords": "Antarctica; Bentic Fauna; Biota; Mcmurdo Sound; Oceans; Ross Sea; Sample/collection Description; Sample/Collection Description; Southern Ocean", "people": "Dayton, Paul", "repository": "USAP-DC", "science_program": null, "title": "A Multi-decadal Record of Antarctic Benthos: Image Analysis to Maximize Data Utilization", "url": "https://www.usap-dc.org/view/dataset/600164"}], "date_created": "Tue, 31 May 2016 00:00:00 GMT", "description": "Antarctic benthic communities are characterized by many species of sponges (Phylum Porifera), long thought to exhibit extremely slow demographic patterns of settlement, growth and reproduction. This project will analyze many hundreds of diver and remotely operated underwater vehicle photographs documenting a unique, episodic settlement event that occurred between 2000 and 2010 in McMurdo Sound that challenges this paradigm of slow growth. Artificial structures were placed on the seafloor between 1967 and 1974 at several sites, but no sponges were observed to settle on these structures until 2004. By 2010 some 40 species of sponges had settled and grown to be surprisingly large. Given the paradigm of slow settlement and growth supported by the long observation period (37 years, 1967-2004), this extraordinary large-scale settlement and rapid growth over just a 6-year time span is astonishing. This project utilizes image processing software (ImageJ) to obtain metrics (linear dimensions to estimate size, frequency, percent cover) for sponges and other fauna visible in the photographs. It uses R to conduct multidimensional scaling to ordinate community data and ANOSIM to test for differences of community data among sites and times and structures. It will also use SIMPER and ranked species abundances to discriminate species responsible for any differences. \u003cbr/\u003e\u003cbr/\u003eThis work focuses on Antarctic sponges, but the observations of massive episodic recruitment and growth are important to understanding seafloor communities worldwide. Ecosystems are composed of populations, and populations are ecologically described by their distribution and abundance. A little appreciated fact is that sponges often dominate marine communities, but because sponges are so hard to study, most workers focus on other groups such as corals, kelps, or bivalves. Because most sponges settle and grow slowly their life history is virtually unstudied. The assumption of relative stasis of the Antarctic seafloor community is common, and this project will shatter this paradigm by documenting a dramatic episodic event. Finally, the project takes advantage of old transects from the 1960s and 1970s and compares them with extensive 2010 surveys of the same habitats and sometimes the same intact transect lines, offering a long-term perspective of community change. The investigators will publish these results in peer-reviewed journals, give presentations to the general public and will involve students from local outreach programs, high schools, and undergraduates at UCSD to help with the analysis.", "east": 167.0, "geometry": "POINT(165 -78.25)", "instruments": null, "is_usap_dc": true, "keywords": "Not provided", "locations": null, "north": -78.0, "nsf_funding_programs": "Antarctic Organisms and Ecosystems", "paleo_time": null, "persons": "Dayton, Paul", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -78.5, "title": "EAGER: A Multi-decadal Record of Antarctic Benthos: Image Analysis to Maximize Data Utilization", "uid": "p0000401", "west": 163.0}, {"awards": "9908828 Aronson, Richard", "bounds_geometry": "POLYGON((-70.906 -52.350166,-69.4494 -52.350166,-67.9928 -52.350166,-66.5362 -52.350166,-65.0796 -52.350166,-63.623 -52.350166,-62.1664 -52.350166,-60.7098 -52.350166,-59.2532 -52.350166,-57.7966 -52.350166,-56.34 -52.350166,-56.34 -53.6028324,-56.34 -54.8554988,-56.34 -56.1081652,-56.34 -57.3608316,-56.34 -58.613498,-56.34 -59.8661644,-56.34 -61.1188308,-56.34 -62.3714972,-56.34 -63.6241636,-56.34 -64.87683,-57.7966 -64.87683,-59.2532 -64.87683,-60.7098 -64.87683,-62.1664 -64.87683,-63.623 -64.87683,-65.0796 -64.87683,-66.5362 -64.87683,-67.9928 -64.87683,-69.4494 -64.87683,-70.906 -64.87683,-70.906 -63.6241636,-70.906 -62.3714972,-70.906 -61.1188308,-70.906 -59.8661644,-70.906 -58.613498,-70.906 -57.3608316,-70.906 -56.1081652,-70.906 -54.8554988,-70.906 -53.6028324,-70.906 -52.350166))", "dataset_titles": "Expedition Data; Expedition data of NBP0107", "datasets": [{"dataset_uid": "002656", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of NBP0107", "url": "https://www.rvdata.us/search/cruise/NBP0107"}, {"dataset_uid": "001962", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0011"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "9908828\u003cbr/\u003eAronson\u003cbr/\u003e\u003cbr/\u003eThis award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a paleoecological and paleoenvironmental study of Seymour Island. Global climate change late in the Eocene epoch had an important influence in Antarctica. This was the beginning of the transition from a cool-temperate climate in Antarctica to the polar climate that exists there today. The cooling trend strongly influenced the structure of shallow-water, Antarctic marine communities, and these effects are still evident in the peculiar ecological relationships among species living in modern Antarctic communities. Cooling late in the Eocene reduced the abundance of fish and crabs, which in turn reduced skeleton-crushing predation on invertebrates. Reduced predation allowed dense populations of ophiuroids (brittlestars) and crinoids (sea lilies) to appear in shallow-water settings at the end of the Eocene. These low-predation communities appear as dense fossil echinoderm assemblages in the upper portion of the late Eocene La Meseta Formation on Seymour Island, off the Antarctic Peninsula. Today, dense ophiuroid and crinoid populations are common in shallow-water habitats in Antarctica but generally have been eliminated by predators from similar habitats at temperate and tropical latitudes; their persistence in Antarctica to this day is an important ecological legacy of climatic cooling in the Eocene. Although the influence of declining predation on Antarctic ophiuroids and crinoids is now well documented, the effects of cooling on the more abundant mollusks have not been investigated. This study will examine the evolutionary ecology of gastropods (snails) and bivalves (clams) in the late Eocene.\u003cbr/\u003e\u003cbr/\u003eA series of hypotheses will be tested in the La Meseta Formation, based on the predicted responses of mollusks to declining temperature and changing levels of predation. The shapes of gastropod shells, the activities of gastropods that prey on other mollusks by drilling holes in their shells, and the effects of predation on the thickness of mollusk shells should have changed significantly through late Eocene time. First, defensive features of gastropod shells, such as spines and ribbing, should decline as temperature and, therefore, the activity of skeleton-crushing predators declined. Second, drilling of bivalve prey by predatory gastropods should increase with time since the drillers should themselves have been subject to lower predation pressure as temperature declined. Drilled shells, therefore, should become more common through time. Third, patterns in the thickness of shells through time will make it possible to separate the direct, physiological effects of declining temperature (shells are more difficult to produce at cooler temperatures, and so should be thinner) from the indirect effects of temperature on evolving biological interactions (increased drilling predation should result in thicker shells). \u003cbr/\u003e\u003cbr/\u003eSeymour Island contains the only fossil outcrops readily accessible in Antarctica from this crucial period in Earth history. The La Meseta Formation on Seymour Island thus provides a unique opportunity to learn how climate change affected Antarctic marine communities. In practical terms, global climate change will probably increase upwelling over the next few decades to centuries in some temperate coastal regions. Recent ecological evidence suggests that the resultant lowering of sea temperatures could lower predation in those areas. Understanding the response of the La Meseta faunas to global cooling in the late Eocene will provide direct insight into the rapidly changing structure of modern benthic communities.", "east": -56.34, "geometry": "POINT(-63.623 -58.613498)", "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e MAGNETIC/MOTION SENSORS \u003e GRAVIMETERS \u003e GRAVIMETERS; IN SITU/LABORATORY INSTRUMENTS \u003e PHOTON/OPTICAL DETECTORS \u003e TURBIDITY METERS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e MSBS", "is_usap_dc": false, "keywords": "R/V NBP; Hugo Island; R/V LMG; Palmer Deep", "locations": "Hugo Island", "north": -52.350166, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Aronson, Richard; Domack, Eugene Walter", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG; WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V NBP", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": -64.87683, "title": "Global Climate Change and the Evolutionary Ecology of Antarctic Mollusks in the Late Eocene", "uid": "p0000617", "west": -70.906}, {"awards": "9908856 Blake, Daniel", "bounds_geometry": null, "dataset_titles": "Expedition Data; Expedition data of LMG0309", "datasets": [{"dataset_uid": "001683", "doi": "", "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition Data", "url": "https://www.rvdata.us/search/cruise/LMG0309"}, {"dataset_uid": "002675", "doi": null, "keywords": null, "people": null, "repository": "R2R", "science_program": null, "title": "Expedition data of LMG0309", "url": "https://www.rvdata.us/search/cruise/LMG0309"}], "date_created": "Tue, 04 May 2010 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a paleoecological and paleoenvironmental study of Seymour Island. Global climate change late in the Eocene epoch had an important influence in Antarctica. This was the beginning of the transition from a cool-temperate climate in Antarctica to the polar climate that exists there today. The cooling trend strongly influenced the structure of shallow-water, Antarctic marine communities, and these effects are still evident in the peculiar ecological relationships among species living in modern Antarctic communities. Cooling late in the Eocene reduced the abundance of fish and crabs, which in turn reduced skeleton-crushing predation on invertebrates. Reduced predation allowed dense populations of ophiuroids (brittlestars) and crinoids (sea lilies) to appear in shallow-water settings at the end of the Eocene. These low-predation communities appear as dense fossil echinoderm assemblages in the upper portion of the late Eocene La Meseta Formation on Seymour Island, off the Antarctic Peninsula. Today, dense ophiuroid and crinoid populations are common in shallow-water habitats in Antarctica but generally have been eliminated by predators from similar habitats at temperate and tropical latitudes; their persistence in Antarctica to this day is an important ecological legacy of climatic cooling in the Eocene. Although the influence of declining predation on Antarctic ophiuroids and crinoids is now well documented, the effects of cooling on the more abundant mollusks have not been investigated. This study will examine the evolutionary ecology of gastropods (snails) and bivalves (clams) in the late Eocene.\u003cbr/\u003e\u003cbr/\u003eA series of hypotheses will be tested in the La Meseta Formation, based on the predicted responses of mollusks to declining temperature and changing levels of predation. The shapes of gastropod shells, the activities of gastropods that prey on other mollusks by drilling holes in their shells, and the effects of predation on the thickness of mollusk shells should have changed significantly through late Eocene time. First, defensive features of gastropod shells, such as spines and ribbing, should decline as temperature and, therefore, the activity of skeleton-crushing predators declined. Second, drilling of bivalve prey by predatory gastropods should increase with time since the drillers should themselves have been subject to lower predation pressure as temperature declined. Drilled shells, therefore, should become more common through time. Third, patterns in the thickness of shells through time will make it possible to separate the direct, physiological effects of declining temperature (shells are more difficult to produce at cooler temperatures, and so should be thinner) from the indirect effects of temperature on evolving biological interactions (increased drilling predation should result in thicker shells). \u003cbr/\u003e\u003cbr/\u003eSeymour Island contains the only fossil outcrops readily accessible in Antarctica from this crucial period in Earth history. The La Meseta Formation on Seymour Island thus provides a unique opportunity to learn how climate change affected Antarctic marine communities. In practical terms, global climate change will probably increase upwelling over the next few decades to centuries in some temperate coastal regions. Recent ecological evidence suggests that the resultant lowering of sea temperatures could lower predation in those areas. Understanding the response of the La Meseta faunas to global cooling in the late Eocene will provide direct insight into the rapidly changing structure of modern benthic communities.", "east": null, "geometry": null, "instruments": "IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e CTD; IN SITU/LABORATORY INSTRUMENTS \u003e PRESSURE/HEIGHT METERS \u003e PRESSURE SENSORS; EARTH REMOTE SENSING INSTRUMENTS \u003e PASSIVE REMOTE SENSING \u003e POSITIONING/NAVIGATION \u003e GPS \u003e GPS; IN SITU/LABORATORY INSTRUMENTS \u003e PROFILERS/SOUNDERS \u003e ACOUSTIC SOUNDERS \u003e ADCP", "is_usap_dc": false, "keywords": "R/V LMG", "locations": null, "north": null, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": null, "persons": "Blake, Daniel", "platforms": "WATER-BASED PLATFORMS \u003e VESSELS \u003e SURFACE \u003e R/V LMG", "repo": "R2R", "repositories": "R2R", "science_programs": null, "south": null, "title": "Global Climate Change and the Evolutionary Ecology of Antarctic Mollusks in the Late Eocene.", "uid": "p0000857", "west": null}, {"awards": "9980538 Lohmann, Kyger", "bounds_geometry": "POINT(-56 -64)", "dataset_titles": "Stable isotope and minor element proxies for Eocene climate of Seymour Island, Antarctica", "datasets": [{"dataset_uid": "600019", "doi": "", "keywords": null, "people": "Lohmann, Kyger", "repository": "USAP-DC", "science_program": null, "title": "Stable isotope and minor element proxies for Eocene climate of Seymour Island, Antarctica", "url": "https://www.usap-dc.org/view/dataset/600019"}], "date_created": "Mon, 11 Jun 2001 00:00:00 GMT", "description": "This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports research for construction of a long-term record of climate during the late Cretaceous and early Paleogene to assess the annual seasonality in temperature on the coastal margin of Antarctica. Stable isotope and element compositions of well-preserved bivalve shells collected on Seymour Island will be the primary source of data used to reconstruct paleoenvironmental conditions. Seasonal temperature records collected through high-resolution sampling along growth structures in bivalve shells will allow seasonality to be assessed during different climate states and during periods of rapid climate change. In addition, high stratigraphic resolution will enable this project to detect the presence and frequency of short-lived thermal excursions that may have extended to such high latitudes.\u003cbr/\u003e\u003cbr/\u003eTo compile a reliable temporal record of paleoclimate, two major avenues of investigation will be undertaken: 1) precise stratigraphic (and therefore, temporal) placement of fossils over a large geographic area will be employed through the use of a graphical technique employing geometric projections; 2) stable isotope and elemental analyses will be performed to derive paleotemperatures and to evaluate diagenetic alteration of shell materials. To provide realistic comparisons of paleotemperatures across stratigraphic horizons, this study will focus on a single taxon, thus avoiding complications due to the mixing of faunal assemblages that have been encountered in previous studies of this region.\u003cbr/\u003e\u003cbr/\u003eThe near-shore marine fossil record on Seymour Island provides a unique opportunity to address many questions about the Antarctic paleoenvironment, including the relation between seasonality and different climate states, the influence of climate on biogeographic distribution of specific taxa, the effect of ice-volume changes on the stable isotope record from the late Cretaceous through the Eocene, and the plausibility of high-latitude bottom water formation during this time interval. In particular, information that will be collected concerning patterns of seasonality and the presence (or absence) of short-lived thermal excursions will be extremely valuable to an understanding of the response of high latitude sites during climate transitions from globally cool to globally warm conditions.", "east": -56.0, "geometry": "POINT(-56 -64)", "instruments": null, "is_usap_dc": false, "keywords": "Not provided; Bivalves; Geochemical Composition; Carbon Isotopes; Climate", "locations": null, "north": -64.0, "nsf_funding_programs": "Antarctic Earth Sciences", "paleo_time": "PHANEROZOIC \u003e CENOZOIC \u003e PALEOGENE \u003e EOCENE", "persons": "Lohmann, Kyger; Barrera, Enriqueta", "platforms": "Not provided", "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -64.0, "title": "Evolution of Sea Surface Temperatures in the Coastal Antarctic Paleoenvironment During the Late Cretaceous and Paleogene", "uid": "p0000613", "west": -56.0}]

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