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Daniel Desbruyères - One of the best experts on this subject based on the ideXlab platform.
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the Hydrothermal Vent Community of a new deep sea field ashadze 1 12 58 n on the mid atlantic ridge
Journal of the Marine Biological Association of the United Kingdom, 2011Co-Authors: Marie-claire Fabri, Patrick Briand, Annaëlle Bargain, Andrey Gebruk, Yves Fouquet, Marie Morineaux, Daniel DesbruyèresAbstract:Ashadze-1 (12° 58′N 44° 51′W, 4080 m) on the Mid-Atlantic Ridge (MAR) is the deepest known active Hydrothermal Vent field. The first observations on this site were numerous clear and black smokers and surprisingly few known symbiotic species dominant in other Vent areas on the MAR. The species most abundant at Ashadze-1 are those usually found at the periphery of Hydrothermal communities: sea-anemones Maractis rimicarivora and chaetopterid polychaetes Phyllochaetopterus sp. nov. This study comprised site mapping and faunal sampling and Ashadze-1 was completely mapped by using the remote operated vehicle 'Victor 6000' and a new high resolution tool available for deep-sea research. A photo-mapping survey was carried out with a long range optical black and white camera. Digitization of substrata and sea-anemones visible on the images was performed by GIS. Spatial distribution of Ma. rimicarivora was distinguished by high densities of 32 ind.m−2 on the western side of the main smoker area. Submersible sampling operations allowed taxonomic identification within a 200 × 110 m area. Carbon, nitrogen and sulphur isotopic ratios were measured in four dominant species to identify their trophic position. The present paper gives the complete maps and describes the faunal Community of the Ashadze-1 Vent field. The results obtained led us to consider this site as an ecosystem in its declining stage. Finally we compare the similarities of this Community to other Hydrothermal communities on the northern MAR.
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The Hydrothermal Vent Community of a new deep-sea field, Ashadze-1, 12°58'N on the Mid-Atlantic Ridge
Journal of the Marine Biological Association of the United Kingdom, 2010Co-Authors: Marie-claire Fabri, Patrick Briand, Annaëlle Bargain, Andrey Gebruk, Yves Fouquet, Marie Morineaux, Daniel DesbruyèresAbstract:Ashadze-1 (12° 58′N 44° 51′W, 4080 m) on the Mid-Atlantic Ridge (MAR) is the deepest known active Hydrothermal Vent field. The first observations on this site were numerous clear and black smokers and surprisingly few known symbiotic species dominant in other Vent areas on the MAR. The species most abundant at Ashadze-1 are those usually found at the periphery of Hydrothermal communities: sea-anemones Maractis rimicarivora and chaetopterid polychaetes Phyllochaetopterus sp. nov. This study comprised site mapping and faunal sampling and Ashadze-1 was completely mapped by using the remote operated vehicle 'Victor 6000' and a new high resolution tool available for deep-sea research. A photo-mapping survey was carried out with a long range optical black and white camera. Digitization of substrata and sea-anemones visible on the images was performed by GIS. Spatial distribution of Ma. rimicarivora was distinguished by high densities of 32 ind.m−2 on the western side of the main smoker area. Submersible sampling operations allowed taxonomic identification within a 200 × 110 m area. Carbon, nitrogen and sulphur isotopic ratios were measured in four dominant species to identify their trophic position. The present paper gives the complete maps and describes the faunal Community of the Ashadze-1 Vent field. The results obtained led us to consider this site as an ecosystem in its declining stage. Finally we compare the similarities of this Community to other Hydrothermal communities on the northern MAR.
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Community dynamics over a decadal scale at Logatchev, 14°45'N, Mid-Atlantic Ridge
Cahiers De Biologie Marine, 2010Co-Authors: Andrey Gebruk, Marie-claire Fabri, Patrick Briand, Daniel DesbruyèresAbstract:Hydrothermal Vent Community dynamics over a ten year span was studied in the Logatchev area, 14 degrees 45'N on the Mid-Atlantic Ridge. On the SERPENTINE cruise in March 2007 with the RN Pourquoi pas? and the ROV Victor 6000 (IFREMER), composition, abundance and distribution of dominant megafauna at Logatchev were examined and compared to published data from 1997. Our results revealed notable changes in several Community characteristics. The most significant changes evident in March 2007 compared to July 1997 were the increase up to by order of magnitude in the population density of predatory gastropods Phymorchynchus spp. at the site Irina-2 and disappearance of a live population of vesicomyids at the site Anya's Garden. Other notable differences between the two periods of observation were the overall increase in the abundance in 2007 of the mussel Bathymodiolus puteoserpentis and a high abundance of gravid females of the shrimp Rimicaris exoculata at Irina-2. It is suggested that the extinction of vesicomyids occurred owing to either a sediment slide at a steep slope of the Anya's Garden locality or instability of a biotope required for vesicomyids. Live vesicomyids were not found over a large area explored at Logatchev in 2007. Other changes observed in 2007 apparently were related to seasonal fluctuations in the Community at Logatchev or fluctuations in the Hydrothermal activity. Any successional stages over a decadal scale at Logatchev were not observed.
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A deep-sea Hydrothermal Vent Community dominated by Stauromedusae
Deep Sea Research Part II: Topical Studies in Oceanography, 1998Co-Authors: Richard A. Lutz, Daniel Desbruyères, Timothy M. Shank, Robert C. VrijenhoekAbstract:Abstract A dense population of stauromedusan scyphozoans (morphologically similar to previously described species within the genus Lucernaria) was encountered in a previously undocumented area of Hydrothermal activity along the crest of the East Pacific Rise (Lat. 20°50.304′N; Long. 109°05.422′W; depth of 2605 m). A few galatheid (Munidopsis subsquamosa) and bythograeid (Bythograea thermydron) crabs and occasional anemones (Cyananthea sp.) were the only other Vent-associated megafauna observed within the region. This report represents: (1) the first documented occurrence of a biological Community dominated by Stauromedusae at an active Hydrothermal Vent; (2) one of the deepest reported occurrences of Stauromedusae in the world’s oceans; and (3) documentation of the existence of a species within a class (Scyphozoa) of organisms that thus far has not been reported from Hydrothermal Vents or other reducing environments.
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Chemical and thermal description of the environment of the Genesis Hydrothermal Vent Community (13 degrees N, EPR)
Cahiers De Biologie Marine, 1998Co-Authors: Pierre-marie Sarradin, Jean-claude Caprais, Patrick Briand, Françoise Gaill, Bruce Shillito, Daniel DesbruyèresAbstract:The objective of this study is to describe the chemical and physical environment surrounding the Vent organisms at the Genesis site (EPR, 2640 m). The main chimney is colonized by Riftia pachyptila, fishes Zoarcidae and crabs Bythograeidae. The top of the smoker is covered with tubes of polychaetes Alvinellidae, the frontier zone by limpet gastropods. Temperature measurements and water sampling were made on an axis along the chimney. The environment was characterized using relationships between chemical concentrations and temperature to provide a chemo-thermal model of the site. Discrete temperature ranges were 1-1.6 degrees C in sea water, 1.6-10 degrees C among Riftia plumes (up to 25 degrees C at the tube base), 7-91 degrees C close to the alvinellid tubes, fluid emission was 262-289 degrees C. This study describes the habitat of Alvinellidae emphasizing its chemical (Sigma S [H2S + HS- + S-2-] 3-300 mu mol l(-1), CO2 3.5-6 mmol l(-1), pH 5.7-7.5) and thermal specificities compared to the Riftia ones (Sigma S 4-12 mu mol l(-1); CO2 2-3.5 mmol l(-1;) pH 5.8-7.7). The size of Riftia allowed us to define its environment at the organism (temperature gradient along the tube 0.5-1 degrees C cm(-1)) and population scales (temperature difference between organisms from the same clump: 10-20 degrees C). Such spatial heterogeneity may play a significant role in the animal physiology and calls for further investigations.
Nilauro Markus - One of the best experts on this subject based on the ideXlab platform.
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Imprint of past environmental regimes on structure and succession of a deep-sea Hydrothermal Vent Community
Oecologia, 2009Co-Authors: Lauren S. Mullineaux, Fiorenza Micheli, Charles H. Peterson, Hunter S. Lenihan, Nilauro MarkusAbstract:Dramatic perturbations of ecological communi- ties through rapid shifts in environmental regime do not always result in complete mortality of residents. Instead, legacy individuals may remain and inXuence the succession and composition of subsequent communities. We used a reciprocal transplant experiment to investigate whether a legacy eVect is detectable in communities experiencing an abrupt increase or decrease in Hydrothermal Xuid Xux at deep-sea Vents. Vent habitats are characterized by strong gradients in productivity and physico-chemical stressors, both of which tend to increase with increasing Vent Xuid Xux. In our experiments, many species survived transplan- tation from cool (water temperatures
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imprint of past environmental regimes on structure and succession of a deep sea Hydrothermal Vent Community
Oecologia, 2009Co-Authors: Lauren S. Mullineaux, Fiorenza Micheli, Charles H. Peterson, Hunter S. Lenihan, Nilauro MarkusAbstract:Dramatic perturbations of ecological communi- ties through rapid shifts in environmental regime do not always result in complete mortality of residents. Instead, legacy individuals may remain and inXuence the succession and composition of subsequent communities. We used a reciprocal transplant experiment to investigate whether a legacy eVect is detectable in communities experiencing an abrupt increase or decrease in Hydrothermal Xuid Xux at deep-sea Vents. Vent habitats are characterized by strong gradients in productivity and physico-chemical stressors, both of which tend to increase with increasing Vent Xuid Xux. In our experiments, many species survived transplan- tation from cool (water temperatures <2°C above ambient) to warm (4-30°C above ambient) habitats, resulting in sig- niWcantly higher species richness on transplanted than remaining experimental substrata. A legacy eVect was much less apparent in transplantation from warm to cool habitat, although a few vestimentiferan tubeworms, nor- mally restricted to warm habitat, survived transplantation. The asymmetry in inXuence of legacy individuals suggests that productivity enhancement may outweigh potential physiological stress in setting limits to distributions of Vent invertebrates. This inXuence of biological processes contrasts with theory developed in the rocky intertidal that predicts the predominance of physical control at the high- stress end of an environmental gradient. Prediction of successional transitions in Vents and other habitats experi- encing regime shifts in which remnant species may survive must take into account the possible inXuence of historical
Lauren S. Mullineaux - One of the best experts on this subject based on the ideXlab platform.
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imprint of past environmental regimes on structure and succession of a deep sea Hydrothermal Vent Community
Oecologia, 2009Co-Authors: Lauren S. Mullineaux, Fiorenza Micheli, Charles H. Peterson, Hunter S. Lenihan, Nilauro MarkusAbstract:Dramatic perturbations of ecological communi- ties through rapid shifts in environmental regime do not always result in complete mortality of residents. Instead, legacy individuals may remain and inXuence the succession and composition of subsequent communities. We used a reciprocal transplant experiment to investigate whether a legacy eVect is detectable in communities experiencing an abrupt increase or decrease in Hydrothermal Xuid Xux at deep-sea Vents. Vent habitats are characterized by strong gradients in productivity and physico-chemical stressors, both of which tend to increase with increasing Vent Xuid Xux. In our experiments, many species survived transplan- tation from cool (water temperatures <2°C above ambient) to warm (4-30°C above ambient) habitats, resulting in sig- niWcantly higher species richness on transplanted than remaining experimental substrata. A legacy eVect was much less apparent in transplantation from warm to cool habitat, although a few vestimentiferan tubeworms, nor- mally restricted to warm habitat, survived transplantation. The asymmetry in inXuence of legacy individuals suggests that productivity enhancement may outweigh potential physiological stress in setting limits to distributions of Vent invertebrates. This inXuence of biological processes contrasts with theory developed in the rocky intertidal that predicts the predominance of physical control at the high- stress end of an environmental gradient. Prediction of successional transitions in Vents and other habitats experi- encing regime shifts in which remnant species may survive must take into account the possible inXuence of historical
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Imprint of past environmental regimes on structure and succession of a deep-sea Hydrothermal Vent Community
Oecologia, 2009Co-Authors: Lauren S. Mullineaux, Fiorenza Micheli, Charles H. Peterson, Hunter S. Lenihan, Nilauro MarkusAbstract:Dramatic perturbations of ecological communi- ties through rapid shifts in environmental regime do not always result in complete mortality of residents. Instead, legacy individuals may remain and inXuence the succession and composition of subsequent communities. We used a reciprocal transplant experiment to investigate whether a legacy eVect is detectable in communities experiencing an abrupt increase or decrease in Hydrothermal Xuid Xux at deep-sea Vents. Vent habitats are characterized by strong gradients in productivity and physico-chemical stressors, both of which tend to increase with increasing Vent Xuid Xux. In our experiments, many species survived transplan- tation from cool (water temperatures
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Identification of archaeogastropod larvae from a Hydrothermal Vent Community
Marine Biology, 1996Co-Authors: Lauren S. Mullineaux, S. L. Kim, A. Pooley, Richard A. LutzAbstract:Dispersal is essential in order that endemic species living in ephemeral, patchy Vent environments may persist over evolutionary time. Quantitative field studies of larval dispersal, however, require specieslevel identification of the larval forms because each individual must be distinguished from related Vent species, and from non-Vent species living in the surrounding deep-sea environment. Methods for culturing these larvae to an identifiable stage have not yet been developed. To solve the larval identification problem for the archaeogastropod molluscs (a prominent component of Vent communities), we used a scanning electron microscope (SEM) to image shells of larvae collected in the water column near Vents along the East Pacific Rise (9°40′ to 9°50′N; 104°W). Larval shell size, shape and ornamentation were compared to protoconchs retained in juvenile or adult shells of identified species, and used to assign five larval groups unequivocally to species (Cyathermia naticoides Waren and Bouchet, 1989; Neomphalus fretterae McLean, 1981; Clypeosectus delectus McLean, 1989; Rhynchopelta concentrica McLean, 1989; and Lirapex granularis Waren and Bouchet, 1989) and seven groups tentatively to species or genus [Lepetodrilus spp. (three groups); Gorgoleptis sp; Peltospira ?operculata McLean, 1989; and ?Melanodrymia sp. (two groups)].
Crispin T. S. Little - One of the best experts on this subject based on the ideXlab platform.
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Microbial-tubeworm associations in a 440 million year old Hydrothermal Vent Community
Proceedings. Biological sciences, 2018Co-Authors: Magdalena N. Georgieva, Crispin T. S. Little, Russell J. Bailey, Alexander Ball, Adrian G. GloverAbstract:Microorganisms are the chief primary producers within present-day deep-sea Hydrothermal Vent ecosystems, and play a fundamental role in shaping the ecology of these environments. However, very litt...
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Electronic Supplementary Material: methods, figures and tables from Microbial-tubeworm associations in a 440-million-year-old Hydrothermal Vent Community
2018Co-Authors: Magdalena N. Georgieva, Crispin T. S. Little, Russell J. Bailey, Alexander D. Ball, Adrian G. GloverAbstract:Microorganisms are the chief primary producers within present-day deep-sea Hydrothermal Vent ecosystems, and play a fundamental role in shaping the ecology of these environments. However, very little is known about the microbes that occurred within, and structured ancient Vent communities. The evolutionary history, diversity and the nature of interactions between ancient Vent microorganisms and Hydrothermal Vent animals are largely undetermined. The oldest known Hydrothermal Vent Community that includes metazoans is preserved within the Ordovician-early Silurian Yaman Kasy massive sulfide deposit, Ural Mountains, Russia. This deposit contains two types of tube fossil attributed to annelid worms. A re-examination of these fossils using a range of microscopy, chemical analysis and nano-tomography techniques reveals the preservation of filamentous microorganisms intimately associated with the tubes. The microfossils bear a strong resemblance to modern Hydrothermal Vent microbial filaments, including those preserved within the mineralized tubes of the extant Vent polychaete genus Alvinella. The Yaman Kasy fossil filaments represent the oldest animal–microbial associations preserved within an ancient Hydrothermal Vent environment. They allude to a diverse microbial Community, and also demonstrate that remarkable fine-scale microbial preservation can also be observed in ancient Vent deposits, suggesting the possible existence of similar exceptionally preserved microfossils in even older Vent environments
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EARLY JURASSIC Hydrothermal Vent Community FROM THE FRANCISCAN COMPLEX, CALIFORNIA
Journal of Paleontology, 2004Co-Authors: Crispin T. S. Little, Taniel Danelian, Richard Herrington, Rachel M. HaymonAbstract:Abstract The Figueroa sulfide deposit located in Franciscan Complex rocks in the San Rafael Mountains, California, contains the only known Jurassic Hydrothermal Vent Community. Based on radiolarian biostratigraphy it is Pliensbachian (early Jurassic) in age. The Figueroa fossil organisms lived at a deepwater, high temperature Vent site located on a mid-ocean ridge or seamount at an equatorial latitude. The Vent site was then translated northeastward by the motion of the Farallon Plate and was subsequently accreted to its present location. The Vent fossils are preserved as molds of pyrite and there is no remaining shell or tube material. The fossil assemblage is specimen rich, but of low diversity, and comprises, in order of decreasing abundance, vestimentiferan worm tubes, rhynchonellide brachiopods (Anarhynchia cf. gabbi), and trochoidean gastropods (Francisciconcha maslennikovi new genus and species). These fossils represent only primary consuming organisms, some of which may have had chemosynthetic mic...
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Early Jurassic Hydrothermal Vent Community from the Franciscan Complex, San Rafael Mountains, California
Geology, 1999Co-Authors: Crispin T. S. Little, Richard Herrington, Rachel M. Haymon, Taniel DanelianAbstract:The Figueroa massive sulfide deposit, located in Franciscan Complex rocks in the San Rafael Mountains of California, preserves the only known Jurassic Hydrothermal Vent fossils. The Figueroa fossil assemblage is specimen rich but of low diversity and comprises, in order of decreasing abundance, vestimentiferan worm tubes, the rhynchonellid brachiopod Anarhynchia cf. gabbi and a species of ?nododelphinulid gastropod. The Figueroa fossil organisms lived at a deep-water, high-temperature Vent site located on a mid-ocean ridge or seamount at an equatorial latitude. The fossil Vent site was then translated northwestward by the motion of the Farallon plate and was subsequently accreted to its present location. An iron-silica exhalite bed, the probable lateral equivalent of the Figueroa deposit, contains abundant filamentous microfossils with two distinct morphologies and probably represents a lower-temperature, diffuse-flow environment. The Figueroa fossil Community was subject to the same environmental conditions as modern Vent communities, but it is unique among modern and other fossil Vent communities in having rhynchonellid brachiopods.
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Silurian Hydrothermal-Vent Community from the southern Urals, Russia
Nature, 1997Co-Authors: Crispin T. S. Little, Richard Herrington, Valeriy V. Maslennikov, Noel J. Morris, Viktor V. ZaykovAbstract:MODERN Hydrothermal-Vent communities are remarkable for being dependent on bacterial chemosynthetic primary production and for having a high percentage of endemic taxa (95% at the species level)1–3. Based on phylogenetic analyses, it has been suggested that some of these taxa are Mesozoic or even Palaeozoic relicts, and that the Vent environment has thus acted as a refuge against evolutionary pressures, such as mass extinctions, that affect other ecosystems1,2,4. However, little is known about ancient Vent communities because fossils have been reported from very few5–11 of a thousand or so documented Vent deposits12. Here we describe a macrofossil assemblage of monoplacophoran molluscs, inarticulate brachiopods, vestimentiferan tube-worms and other tubes, probably of polychaete origin, from the Silurian Yaman Kasy deposit12. The assemblage represents the oldest, and most diverse, fossil Hydrothermal-Vent Community known, and shares vestimentiferan and polychaete tube-worms with both modern Vent communities1,2 and other ancient Vent assemblages7–12, but is unique in having brachiopods and monoplaco-phorans. Modern Vent communities are not refuges for these Silurian shelly Vent taxa, a finding that may have implications for the refuge hypothesis.
Taniel Danelian - One of the best experts on this subject based on the ideXlab platform.
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EARLY JURASSIC Hydrothermal Vent Community FROM THE FRANCISCAN COMPLEX, CALIFORNIA
Journal of Paleontology, 2004Co-Authors: Crispin T. S. Little, Taniel Danelian, Richard Herrington, Rachel M. HaymonAbstract:Abstract The Figueroa sulfide deposit located in Franciscan Complex rocks in the San Rafael Mountains, California, contains the only known Jurassic Hydrothermal Vent Community. Based on radiolarian biostratigraphy it is Pliensbachian (early Jurassic) in age. The Figueroa fossil organisms lived at a deepwater, high temperature Vent site located on a mid-ocean ridge or seamount at an equatorial latitude. The Vent site was then translated northeastward by the motion of the Farallon Plate and was subsequently accreted to its present location. The Vent fossils are preserved as molds of pyrite and there is no remaining shell or tube material. The fossil assemblage is specimen rich, but of low diversity, and comprises, in order of decreasing abundance, vestimentiferan worm tubes, rhynchonellide brachiopods (Anarhynchia cf. gabbi), and trochoidean gastropods (Francisciconcha maslennikovi new genus and species). These fossils represent only primary consuming organisms, some of which may have had chemosynthetic mic...
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Early Jurassic Hydrothermal Vent Community from the Franciscan Complex, San Rafael Mountains, California
Geology, 1999Co-Authors: Crispin T. S. Little, Richard Herrington, Rachel M. Haymon, Taniel DanelianAbstract:The Figueroa massive sulfide deposit, located in Franciscan Complex rocks in the San Rafael Mountains of California, preserves the only known Jurassic Hydrothermal Vent fossils. The Figueroa fossil assemblage is specimen rich but of low diversity and comprises, in order of decreasing abundance, vestimentiferan worm tubes, the rhynchonellid brachiopod Anarhynchia cf. gabbi and a species of ?nododelphinulid gastropod. The Figueroa fossil organisms lived at a deep-water, high-temperature Vent site located on a mid-ocean ridge or seamount at an equatorial latitude. The fossil Vent site was then translated northwestward by the motion of the Farallon plate and was subsequently accreted to its present location. An iron-silica exhalite bed, the probable lateral equivalent of the Figueroa deposit, contains abundant filamentous microfossils with two distinct morphologies and probably represents a lower-temperature, diffuse-flow environment. The Figueroa fossil Community was subject to the same environmental conditions as modern Vent communities, but it is unique among modern and other fossil Vent communities in having rhynchonellid brachiopods.
