scholarly journals The Biogeography of Islands: Preliminary Results from a Comparative Study of the Isles of Scilly and Cornwall

1996 ◽  
Vol 76 (1) ◽  
pp. 219-222 ◽  
Author(s):  
M.M. Kendall ◽  
S. Widdicombe ◽  
J.J. Davey ◽  
P.P. Somerfield ◽  
M.C.V. Austen ◽  
...  
Keyword(s):  
Island Biogeography ◽  
Hydrothermal Vents ◽  
Deep Ocean ◽  
Small Islands ◽  
Shallow Marine ◽  
Α Diversity ◽  
Remote Island ◽  
Planktonic Larvae ◽  
The Subject ◽  
Planktotrophic Larvae

Studies of the interplay of immigration, emigration and extinction in shaping the fauna of islands (McArthur & Wilson, 1967) have influenced the terrestrial ecologists view of the creation and maintenance of diversity. Although in the deep ocean, hydrothermal vents have been the subject of a number of biogeographic studies (Tunnicliffe, 1991), there have been few attempts to validate theories of island biogeography in the shallow marine environment. To rectify this situation, a study comparing the fauna of the mainland of Cornwall, with that of the Isles of Scilly, which lie 45 km from the mainland and were separated from it ~0·3 my BP has been undertaken.Evidence for some comparative impoverishment of the Isles of Scilly fauna was provided by Crisp & Southward (1958) who noted that a small number of cirripedes and molluscs with planktonic larvae, living close to their geographic limits of distribution in Cornwall, were unable to bridge the gap to the islands. They suggested that although species with long-lived planktonic larvae can be widely dispersed, excessive dispersal can lead to their loss from the fauna of small islands. This is clearly demonstrated on the remote island of Rockall where both Crisp (1956) and Moore (1977) noted that only animals with direct development occur. On the Island of Lundy, four species of gastropod were estimated to be less abundant than on the mainland which lies only 18 km away (Hawkins & Hiscock, 1983). However, such studies only deal with a small number of conspicuous intertidal species, and there is a requirement to expand observations to the community level. The present study attempts to question the following hypotheses: (1) α - diversity (that of single samples) is lower on the islands than the mainland; (2) the diversity of species with planktotrophic larvae is lower on the islands than on the mainland.

From wood to vent: first cocculinid limpet associated with hydrothermal activity discovered in the Weddell Sea

2020 ◽  
Vol 32 (5) ◽  
pp. 354-366
Author(s):  
Chong Chen ◽  
Katrin Linse
Keyword(s):  
Hydrothermal Vents ◽  
Deep Ocean ◽  
First Record ◽  
Hydrothermal Activity ◽  
Integrative Taxonomy ◽  
Weddell Sea ◽  
Anatomical Reconstruction ◽  
Cold Seeps ◽  
Evolutionary Trajectory ◽  
Genetic Sequencing

AbstractLush ‘oases’ of life seen in chemosynthetic ecosystems such as hot vents and cold seeps represent rare, localized exceptions to the generally oligotrophic deep ocean floor. Organic falls, best known from sunken wood and whale carcasses, are additional sources of such oases. Kemp Caldera (59°42'S, 28°20'W) in the Weddell Sea exhibits active hydrothermal vents and a natural whale fall in close proximity, where an undescribed cocculinid limpet was found living in both types of chemosynthetic habitats. This represents the first member of the gastropod order Cocculinida discovered from hot vents, and also the first record from the Southern Ocean. Here, we applied an integrative taxonomy framework incorporating traditional dissection, electron microscopy, genetic sequencing and 3D anatomical reconstruction through synchrotron computed tomography in order to characterize this species. Together, our data revealed an unusual member of the genus Cocculina with a highly modified radula for feeding on bacterial film, described herein as Cocculina enigmadonta n. sp. Its phylogenetically derived position within the largely wood-inhabiting Cocculina indicates that it probably evolved from an ancestor adapted to living on sunken wood, providing a compelling case of the ‘stepping stone’ evolutionary trajectory from organic falls to seeps and vents.

Disposal in the deep sea: analogue of nature or faux ami?

2003 ◽  
Vol 30 (1) ◽  
pp. 26-39 ◽  
Author(s):  
Paul A. Tyler
Keyword(s):  
Carbon Dioxide ◽  
Radioactive Waste ◽  
Deep Sea ◽  
Hydrothermal Vents ◽  
Natural Radionuclides ◽  
Deep Ocean ◽  
Turbidity Currents ◽  
Chemical Contamination ◽  
Seabed Sediment ◽  
Dredge Spoil

The deep sea is the world's largest ecosystem by volume and is assumed to have a high assimilative capacity. Natural events, such as the sinking of surface plant and animal material to the seabed, sediment slides, benthic storms and hydrothermal vents can contribute vast amounts of material, both organic and inorganic, to the deep ocean. In the past the deep sea has been used as a repository for sewage, dredge spoil and radioactive waste. In addition, there has been interest in the disposal of large man-made objects and, more recently, the disposal of industrially-produced carbon dioxide. Some of the materials disposed of in the deep sea may have natural analogues. This review examines natural processes in the deep sea including the vertical flux of organic material, turbidity currents and benthic storms, natural gas emissions, hydrothermal vents, natural radionuclides and rocky substrata, and compares them with anthropogenic input including sewage disposal, dredge spoil, carbon dioxide disposal, chemical contamination and the disposal of radioactive waste, wrecks and rigs. The comparison shows what are true analogues and what are false friends. Knowledge of the deep sea is fragmentary and much more needs to be known about this large, biologically-diverse system before any further consideration is given to its use in the disposal of waste.

scholarly journals Isolation of Tellurite- and Selenite-Resistant Bacteria from Hydrothermal Vents of the Juan de Fuca Ridge in the Pacific Ocean

2002 ◽  
Vol 68 (9) ◽  
pp. 4613-4622 ◽  
Author(s):  
Christopher Rathgeber ◽  
Natalia Yurkova ◽  
Erko Stackebrandt ◽  
J. Thomas Beatty ◽  
Vladimir Yurkov
Keyword(s):  
Hydrothermal Vents ◽  
Deep Ocean ◽  
Juan De Fuca Ridge ◽  
Resistant Bacteria ◽  
Ocean Water ◽  
Bacterial Films ◽  
The Pacific ◽  
Juan De Fuca ◽  
The Pacific Ocean ◽  
Reducing Bacteria

ABSTRACT Deep-ocean hydrothermal-vent environments are rich in heavy metals and metalloids and present excellent sites for the isolation of metal-resistant microorganisms. Both metalloid-oxide-resistant and metalloid-oxide-reducing bacteria were found. Tellurite- and selenite-reducing strains were isolated in high numbers from ocean water near hydrothermal vents, bacterial films, and sulfide-rich rocks. Growth of these isolates in media containing K2TeO3 or Na2SeO3 resulted in the accumulation of metallic tellurium or selenium. The MIC of K2TeO3 ranged from 1,500 to greater than 2,500 μg/ml, and the MIC of Na2SeO3 ranged from 6,000 to greater than 7,000 μg/ml for 10 strains. Phylogenetic analysis of 4 of these 10 strains revealed that they form a branch closely related to members of the genus Pseudoalteromonas, within the γ-3 subclass of the Proteobacteria. All 10 strains were found to be salt tolerant, pH tolerant, and thermotolerant. The metalloid resistance and morphological, physiological, and phylogenetic characteristics of newly isolated strains are described.

scholarly journals Maintenance of biodiversity on islands

2016 ◽  
Vol 283 (1829) ◽  
pp. 20160102 ◽  
Author(s):  
Ryan A. Chisholm ◽  
Tak Fung ◽  
Deepthi Chimalakonda ◽  
James P. O'Dwyer
Keyword(s):  
Species Richness ◽  
Island Biogeography ◽  
Mechanistic Model ◽  
Neutral Theory ◽  
Small Island ◽  
Small Islands ◽  
Island Area ◽  
Island Species ◽  
Theory Of Island Biogeography ◽  
Species Area

MacArthur and Wilson's theory of island biogeography predicts that island species richness should increase with island area. This prediction generally holds among large islands, but among small islands species richness often varies independently of island area, producing the so-called ‘small-island effect’ and an overall biphasic species–area relationship (SAR). Here, we develop a unified theory that explains the biphasic island SAR. Our theory's key postulate is that as island area increases, the total number of immigrants increases faster than niche diversity. A parsimonious mechanistic model approximating these processes reproduces a biphasic SAR and provides excellent fits to 100 archipelago datasets. In the light of our theory, the biphasic island SAR can be interpreted as arising from a transition from a niche-structured regime on small islands to a colonization–extinction balance regime on large islands. The first regime is characteristic of classic deterministic niche theories; the second regime is characteristic of stochastic theories including the theory of island biogeography and neutral theory. The data furthermore confirm our theory's key prediction that the transition between the two SAR regimes should occur at smaller areas, where immigration is stronger (i.e. for taxa that are better dispersers and for archipelagos that are less isolated).

Addendum

1986 ◽  
Vol 227 (1246) ◽  
pp. 145-145
Keyword(s):  
Primary Production ◽  
Electron Acceptor ◽  
Deep Sea ◽  
Hydrothermal Vents ◽  
Inorganic Compounds ◽  
Anaerobic Bacteria ◽  
Deep Ocean ◽  
Extended Period ◽  
Point Of View ◽  
The Common

Review Lecture. The chemosynthetic support of life and the microbial diversity at deep-sea hydrothermal vents. Proc. R. Soc. Lond . B 225, 277-297 (1985). In this lecture, the chemosynthetic base of the food chain supporting rich deep-sea ecosystems around hydrothermal vents, was claimed to represent a primary production of organic carbon independent of sunlight. I received several comments criticizing this point of view for neglecting the fact that oxygen is the required electron acceptor in the metabolism of the eukaryotic part of the vent communities. I agree. The independence of light was, however, mentioned in connection with a catastrophic darkening of the globe’s surface. A temporary absence of photo­synthetic oxygen production might well be overcome for an extended period of time by the ‘aerobic’ deep-sea vent animals, given the minute consumption of oxygen relative to its huge total quantity available in deep ocean waters. In a permanent absence of light, however, the existence of eukaryotic organisms, as we know them, will depend on an oxygen-producing process such as photosynthesis. Populations of anaerobic bacteria, on the other hand, may well persist and differentiate into prokaryotic ecosystems in permanent darkness as long as the geothermal provision of H 2 and CO 2 continues. Physical chemists were troubled by the use of the term ‘source of energy’ for reduced inorganic compounds, such as H 2 S, in chemosynthesis because the actual amount of free energy available depends on the reaction with the oxidant. It is certainly true that the common equalization of the terms ‘electron donor’ and ‘energy source’ in microbial physiology does not take the specific type of electron acceptor into account. They are used as terms of convenience. In my discussion of deep-sea chemosynthesis as a form of primary production, the emphasis on terrestrial chemical ‘sources of energy’ was meant to illustrate the contrast to the use of solar energy which does not only supply oxygen as the most efficient electron acceptor but also the common electron donors, organic as well as inorganic, for all non-phototrophic life in surface waters and on the continents.

Annual spawning cycles and planktonic larvae of benthic invertebrates from Passamaquoddy Bay, New Brunswick

1981 ◽  
Vol 59 (3) ◽  
pp. 433-440 ◽  
Author(s):  
T. Lacalli
Keyword(s):  
Benthic Invertebrates ◽  
Diatom Bloom ◽  
Spawning Period ◽  
Polychaete Species ◽  
Lecithotrophic Larva ◽  
Planktonic Larvae ◽  
Passamaquoddy Bay ◽  
Planktotrophic Larvae ◽  
Spawning Periods ◽  
First Time

Periods of larval occurrence are reported for 19 polychaete species and 10 other common planktonic larvae. Egg sizes are given for 29 polychaete species with estimates of spawning period for 14 of these based on studies of the adult worms. Spawning periods are shown to correlate better with larval type (e.g. whether planktotrophic or lecithotrophic) than with the zoogeographic distribution of the adults. Among the planktotrophic larvae, the evidence suggests that some larvae (e.g. polynoid larvae) develop successfully only during the spring diatom bloom, and gamete wastage may result from any substantial mismatch between the diatom bloom and spawning period. The lecithotrophic larva of the tunicate Boltenia ovifera, which spawns in midwinter, is described for the first time.

scholarly journals Abiotic synthesis of graphite in hydrothermal vents

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Emily R. Estes ◽  
Debora Berti ◽  
Nicole R. Coffey ◽  
Michael F. Hochella ◽  
Andrew S. Wozniak ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Hydrothermal Vents ◽  
Direct Evidence ◽  
Settling Velocity ◽  
East Pacific Rise ◽  
Deep Ocean ◽  
Analytical Techniques ◽  
Filtration Method ◽  
East Pacific ◽  
Marine Organic Carbon

AbstractDeciphering the origin, age, and composition of deep marine organic carbon remains a challenge in understanding the dynamics of the marine carbon cycle. In particular, the composition of aged organic carbon and what allows its persistence in the deep ocean and in sediment is unresolved. Here, we observe that both high and low temperature hydrothermal vents at the 9° 50′ N; 104° 17.5 W East Pacific Rise (EPR) vent field are a source for (sub)micron-sized graphite particles. We demonstrate that commonly applied analytical techniques for quantification of organic carbon detect graphite. These analyses thereby classify graphite as either dissolved or particulate organic carbon, depending on the particle size and filtration method, and overlook its relevance as a carbon source to the deep ocean. Settling velocity calculations indicate the potential for these (sub)micron particles to become entrained in the buoyant plume and distributed far from the vent fields. Thus, our observations provide direct evidence for hydrothermal vents acting as a source of old carbon to the deep ocean.

Hydrothermal vents: A previously unrecognized source of actinium-227 to the deep ocean

2022 ◽  
pp. 104084
Author(s):  
Lauren E. Kipp ◽  
Matthew A. Charette ◽  
Douglas E. Hammond ◽  
Willard S. Moore
Keyword(s):  
Hydrothermal Vents ◽  
Deep Ocean

Distribution of external parasites indicates boundaries to dispersal of sillaginid fishes in the Indo-West Pacific

1997 ◽  
Vol 48 (5) ◽  
pp. 391 ◽  
Author(s):  
Craig J. Hayward
Keyword(s):  
Continental Shelf ◽  
Arabian Sea ◽  
Deep Ocean ◽  
Ocean Floor ◽  
Parasite Diversity ◽  
West Pacific ◽  
Eastern Indonesia ◽  
Planktonic Larvae ◽  
Sillago Sihama ◽  
High Parasite

The distribution of sillaginid-specific ectoparasites permits the distinction of two provinces with high parasite diversity: one on the continental shelf of Australia, and one on the shelf of Asia. The Australian province has 15 endemics (five monogeneans, one leech and nine copepods), and the Asian province has 14 endemics (two monogeneans and 12 copepods). These provinces are separated by a region with coastlines that descend very steeply to the ocean floor and by deep ocean waters that largely inhibit sillaginid movements. Some sillaginids must have dispersed across eastern Indonesia, however, leading to the occurrence of four parasites in both provinces. Three Australian parasites also appear to be presently encroaching onto the southern periphery of the Asian shelf. At least one less-recent invasion of Australian waters by Asian sillaginids would account for the occurrence of six pairs of copepod congeners that have one member in each province. The most widespread sillaginid, Sillago sihama, seems to have dispersed to African shores from the Arabian Sea as planktonic larvae only (no Asian parasites were present in samples of 29 hosts) and relatively recently (only one locally endemic parasite appears to have been acquired).

Constraints on the amplitude of Mid-Pliocene (3.6–2.4 Ma) eustatic sea-level fluctuations from the New Zealand shallow-marine sediment record

2008 ◽  
Vol 367 (1886) ◽  
pp. 169-187 ◽  
Author(s):  
Tim R Naish ◽  
Gary S Wilson
Keyword(s):  
New Zealand ◽  
Sea Level ◽  
Sediment Accumulation ◽  
Ice Sheet ◽  
Deep Ocean ◽  
Antarctic Ice Sheet ◽  
Shallow Marine ◽  
Sea Level Fluctuations ◽  
Late Neogene ◽  
Sea Level Oscillations

Ice-volume calibrations of the deep-ocean foraminiferal δ 18 O record imply orbitally influenced sea-level fluctuations of up to 30 m amplitude during the Mid-Pliocene, and up to 30 per cent loss of the present-day mass of the East Antarctic Ice Sheet (EAIS) assuming complete deglaciation of the West Antarctic Ice Sheet (WAIS) and Greenland. These sea-level oscillations have driven recurrent transgressions and regressions across the world's continental shelves. Wanganui Basin, New Zealand, contains the most complete shallow-marine Late Neogene stratigraphic record in the form of a continuous cyclostratigraphy representing every 41 and 100 ka sea-level cycle since ca 3.6 Ma. This paper presents a synthesis of faunally derived palaeobathymetric data for shallow-marine sedimentary cycles corresponding to marine isotope stages M2–100 ( ca 3.4–2.4 Ma). Our approach estimates the eustatic sea-level contribution to the palaeobathymetry curve by placing constraints on total subsidence and decompacted sediment accumulation. The sea-level estimates are consistent with those from δ 18 O curves and numerical ice sheet models, and imply a significant sensitivity of the WAIS and the coastal margins of the EAIS to orbital oscillations in insolation during the Mid-Pliocene period of relative global warmth. Sea-level oscillations of 10–30 m were paced by obliquity.

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