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Mary Turnipseed

Bio: Mary Turnipseed is an academic researcher from Duke University. The author has contributed to research in topics: Public trust doctrine & Environmental law. The author has an hindex of 12, co-authored 16 publications receiving 1210 citations. Previous affiliations of Mary Turnipseed include University of California, Santa Barbara & College of William & Mary.

Papers
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Journal ArticleDOI
12 Feb 2010-Science
TL;DR: Sustaining seafood's contributions to food security hinges on the ability of institutions, particularly in developing countries, to protect and improve ecosystem health in the face of increasing pressures from international trade.
Abstract: Although seafood is the most highly traded food internationally, it is an often overlooked component of global food security. It provides essential local food, livelihoods, and export earnings. Although global capture fisheries production is unlikely to increase, aquaculture is growing considerably. Sustaining seafood's contributions to food security hinges on the ability of institutions, particularly in developing countries, to protect and improve ecosystem health in the face of increasing pressures from international trade.

457 citations

Journal ArticleDOI
26 Oct 2001-Science
TL;DR: Most organisms found at these Indian Ocean vent fields have evolutionary affinities with western Pacific vent faunas, but a shrimp that ecologically dominates Indian Ocean vents closely resembles its Mid-Atlantic counterpart.
Abstract: Within the endemic invertebrate faunas of hydrothermal vents, five biogeographic provinces are recognized. Invertebrates at two Indian Ocean vent fields (Kairei and Edmond) belong to a sixth province, despite ecological settings and invertebrate-bacterial symbioses similar to those of both western Pacific and Atlantic vents. Most organisms found at these Indian Ocean vent fields have evolutionary affinities with western Pacific vent faunas, but a shrimp that ecologically dominates Indian Ocean vents closely resembles its Mid-Atlantic counterpart. These findings contribute to a global assessment of the biogeography of chemosynthetic faunas and indicate that the Indian Ocean vent community follows asymmetric assembly rules biased toward Pacific evolutionary alliances.

309 citations

Journal ArticleDOI
TL;DR: In this article, the first submersible reconnaissance of the Blake Ridge Diapir provides the geological and ecological contexts for chemosynthetic communities established in close association with methane seeps.
Abstract: Observations from the first submersible reconnaissance of the Blake Ridge Diapir provide the geological and ecological contexts for chemosynthetic communities established in close association with methane seeps. The seeps mark the loci of focused venting of methane from the gas hydrate reservoir, and, in one location (Hole 996D of the Ocean Drilling Program), methane emitted at the seafloor was observed forming gas hydrate on the underside of a carbonate overhang. Megafaunal elements of a chemosynthetically based community mapped onto dive tracks provide a preliminary overview of faunal distributions and habitat heterogeneity. Dense mussel beds were prominent and covered 20 � 20 m areas. The nearly non-overlapping distributions of mussels and clams indicate that there may be local (meter-scale) variations in fluid flux and chemistry within the seep site. Preliminary evidence suggests that the mussels are host to two symbiont types (sulfide-oxidizing thiotrophs and methanotrophs), while the clams derive their nutrition only from thiotrophic bacteria. Invertebrate biomass is dominated by mussels (Bathymodiolus heckerae) that reach lengths of up to 364 mm and, to a lesser extent, by small (22 mm length) vesicomyid clams (Vesicomya cf. venusta). Taking into account biomass distributions among taxa, symbiont characteristics of the bivalves, and stable-isotope analyses, the relative importance of methanotrophic vs thiotrophic bacteria in the overall nutrition of the invertebrate

163 citations

Journal ArticleDOI
TL;DR: This paper evaluated diversity indices for invertebrates associated with mussel beds at six deep-sea hydrothermal vents and two seeps and found that invertebrate diversity was significantly higher at seeps than vents.
Abstract: Remarkably little is known about fundamental distinctions (or similarities) between the faunas of deep-sea hydrothermal vents and seeps. Low species richness at vents has been attributed to the transient nature of vent habitats and to toxic effects of hydrogen sulphide and heavy metals in vent effluents. Seeps are arguably more stable and more chemically benign than vents. They have also been regarded as more diverse, but until now there has not been a rigorous test of this hypothesis. We evaluated diversity indices for invertebrates associated with mussel beds at six vents and two seeps and found that invertebrate diversity was significantly higher at seeps than vents, although some vent mussel beds supported nearly the same diversity as seep mussel beds. Lower diversity at vents may be a consequence of a greater physiological barrier to invasion at vents than at seeps. Diversity was lowest where spacing between vents was greatest, suggesting that risks of extinction as a result of dispersal-related processes may contribute to the pattern of diversity observed at vents.

63 citations

Journal ArticleDOI
TL;DR: The fauna associated with the Bear Seamount was little known until twenty trawl stations were made 2-7 December 2000, by the NOAA ship Delaware II, to begin to document the biodiversity on and over the seamount, particularly of fishes, cephalopods, and crustaceans.
Abstract: Bear Seamount (39 55’N 67 30’W) is an extinct undersea volcano located inside the U.S. Exclusive Economic Zone south of Georges Bank. The fauna associated with the seamount was little known until twenty trawl stations were made 2-7 December 2000, by the NOAA ship Delaware II. The objective of the cruise was to begin to document the biodiversity on and over the seamount, particularly of fishes, cephalopods, and crustaceans. Representatives of most species were preserved as vouchers and for subsequent definitive identification. Preliminary identifications indicate the capture of 115 fish species. Among these were a number of new fish records for the area or rare species, including Acromycter pertubator (Congridae), Alepocephalus bairdii (Alepocephalidae), Mirognathus normani (Alepocephalidae), Bathygadus favosus (Bathygadidae), Nezumia longebarbata (Macrouridae), Gaidropsarus argentatus (Phycidae), and Dibranchus tremendus (Ogcocephalidae). Only two fish species of potential commercial importance were encountered: Coryphaenoides rupestris and Macrourus berglax. Cephalopods comprised 26 species in 15 families, including one new distributional record and several rarelycollected species. The crustacean fauna was diverse with at least 46 species. Totals for other invertebrate species are pending laboratory identification, but number at least 113 species in 10 phyla. This includes a number of new distributional records and a new species of gorgonian.

57 citations


Cited by
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Journal ArticleDOI
12 Feb 2010-Science
TL;DR: A multifaceted and linked global strategy is needed to ensure sustainable and equitable food security, different components of which are explored here.
Abstract: Continuing population and consumption growth will mean that the global demand for food will increase for at least another 40 years. Growing competition for land, water, and energy, in addition to the overexploitation of fisheries, will affect our ability to produce food, as will the urgent requirement to reduce the impact of the food system on the environment. The effects of climate change are a further threat. But the world can produce more food and can ensure that it is used more efficiently and equitably. A multifaceted and linked global strategy is needed to ensure sustainable and equitable food security, different components of which are explored here.

9,125 citations

Journal ArticleDOI
07 Nov 2002-Nature
TL;DR: It is suggested that consolidation of extinction learning potentiates infralimbic activity, which inhibits fear during subsequent encounters with fear stimuli, indicating that medial prefrontal cortex might store long-term extinction memory.
Abstract: Conditioned fear responses to a tone previously paired with a shock diminish if the tone is repeatedly presented without the shock, a process known as extinction. Since Pavlov it has been hypothesized that extinction does not erase conditioning, but forms a new memory. Destruction of the ventral medial prefrontal cortex, which consists of infralimbic and prelimbic cortices, blocks recall of fear extinction, indicating that medial prefrontal cortex might store long-term extinction memory. Here we show that infralimbic neurons recorded during fear conditioning and extinction fire to the tone only when rats are recalling extinction on the following day. Rats that froze the least showed the greatest increase in infralimbic tone responses. We also show that conditioned tones paired with brief electrical stimulation of infralimbic cortex elicit low freezing in rats that had not been extinguished. Thus, stimulation resembling extinction-induced infralimbic tone responses is able to simulate extinction memory. We suggest that consolidation of extinction learning potentiates infralimbic activity, which inhibits fear during subsequent encounters with fear stimuli.

1,694 citations

Journal ArticleDOI
09 Jul 2015-PLOS ONE
TL;DR: The substrate and nutritional heterogeneity introduced by authigenic seep carbonates act to promote diverse, uniquely adapted assemblages, even after seepage ceases, demonstrating the significant role of carbonate rocks in promoting diversity.
Abstract: Carbonate communities: The activity of anaerobic methane oxidizing microbes facilitates precipitation of vast quantities of authigenic carbonate at methane seeps. Here we demonstrate the significant role of carbonate rocks in promoting diversity by providing unique habitat and food resources for macrofaunal assemblages at seeps on the Costa Rica margin (400–1850 m). The attendant fauna is surprisingly similar to that in rocky intertidal shores, with numerous grazing gastropods (limpets and snails) as dominant taxa. However, the community feeds upon seep-associated microbes. Macrofaunal density, composition, and diversity on carbonates vary as a function of seepage activity, biogenic habitat and location. The macrofaunal community of carbonates at non-seeping (inactive) sites is strongly related to the hydrography (depth, temperature, O2) of overlying water, whereas the fauna at sites of active seepage is not. Densities are highest on active rocks from tubeworm bushes and mussel beds, particularly at the Mound 12 location (1000 m). Species diversity is higher on rocks exposed to active seepage, with multiple species of gastropods and polychaetes dominant, while crustaceans, cnidarians, and ophiuroids were better represented on rocks at inactive sites. Macro-infauna (larger than 0.3 mm) from tube cores taken in nearby seep sediments at comparable depths exhibited densities similar to those on carbonate rocks, but had lower diversity and different taxonomic composition. Seep sediments had higher densities of ampharetid, dorvilleid, hesionid, cirratulid and lacydoniid polychaetes, whereas carbonates had more gastropods, as well as syllid, chrysopetalid and polynoid polychaetes. Stable isotope signatures and metrics: The stable isotope signatures of carbonates were heterogeneous, as were the food sources and nutrition used by the animals. Carbonate δ13Cinorg values (mean = -26.98‰) ranged from -53.3‰ to +10.0‰, and were significantly heavier than carbonate δ13Corg (mean = -33.83‰), which ranged from -74.4‰ to -20.6‰. Invertebrates on carbonates had average δ13C (per rock) = -31.0‰ (range -18.5‰ to -46.5‰) and δ15N = 5.7‰ (range -4.5‰ to +13.4‰). Average δ13C values did not differ between active and inactive sites; carbonate fauna from both settings depend on chemosynthesis-based nutrition. Community metrics reflecting trophic diversity (SEAc, total Hull Area, ranges of δ13C and δ15N) and species packing (mean distance to centroid, nearest neighbor distance) also did not vary as a function of seepage activity or site. However, distinct isotopic signatures were observed among related, co-occurring species of gastropods and polychaetes, reflecting intense microbial resource partitioning. Overall, the substrate and nutritional heterogeneity introduced by authigenic seep carbonates act to promote diverse, uniquely adapted assemblages, even after seepage ceases. The macrofauna in these ecosystems remain largely overlooked in most surveys, but are major contributors to biodiversity of chemosynthetic ecosystems and the deep sea in general.

1,685 citations

Journal ArticleDOI
TL;DR: In this article, the authors make a case for a closer integration of fish into the overall debate and future policy about food security and nutrition, making a case that fish is one of the most efficient converters of feed into high quality food and its carbon footprint is lower compared to other animal production systems.
Abstract: Fish provides more than 4.5 billion people with at least 15 % of their average per capita intake of animal protein. Fish’s unique nutritional properties make it also essential to the health of billions of consumers in both developed and developing countries. Fish is one of the most efficient converters of feed into high quality food and its carbon footprint is lower compared to other animal production systems. Through fish-related activities (fisheries and aquaculture but also processing and trading), fish contribute substantially to the income and therefore to the indirect food security of more than 10 % of the world population, essentially in developing and emergent countries. Yet, limited attention has been given so far to fish as a key element in food security and nutrition strategies at national level and in wider development discussions and interventions. As a result, the tremendous potential for improving food security and nutrition embodied in the strengthening of the fishery and aquaculture sectors is missed. The purpose of this paper is to make a case for a closer integration of fish into the overall debate and future policy about food security and nutrition. For this, we review the evidence from the contemporary and emerging debates and controversies around fisheries and aquaculture and we discuss them in the light of the issues debated in the wider agriculture/farming literature. The overarching question that underlies this paper is: how and to what extent will fish be able to contribute to feeding 9 billion people in 2050 and beyond?

591 citations

Journal ArticleDOI
15 Feb 2002-Science
TL;DR: The recent evolution of many vent and seep invertebrate species suggests that Cenozoic tectonic history and oceanic circulation patterns have been important in defining contemporary biogeographic patterns.
Abstract: Deep-sea hydrothermal vents and cold seeps are submarine springs where nutrient-rich fluids emanate from the sea floor. Vent and seep ecosystems occur in a variety of geological settings throughout the global ocean and support food webs based on chemoautotrophic primary production. Most vent and seep invertebrates arrive at suitable habitats as larvae dispersed by deep-ocean currents. The recent evolution of many vent and seep invertebrate species (<100 million years ago) suggests that Cenozoic tectonic history and oceanic circulation patterns have been important in defining contemporary biogeographic patterns.

544 citations