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Limacina Antarctica
''Limacina rangii'' is a species of swimming sea snail in the family Limacinidae,Bouchet, P. (2014). Limacina rangii (d'Orbigny, 1834). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=719583 on 2015-01-24 which belong to the group commonly known as sea butterflies (Thecosomata). ''Limacina rangii'' is a keystone species of the mesozooplankton of Antarctic pelagic ecosystems. Until 2010 this taxon was known only as ''Limacina helicina antarctica'' or as ''Limacina helicina'' f. ''antarctica''. ''Limacina rangii'' is however now considered to be a separate species from ''Limacina helicina'', based on cytochrome c oxidase subunit I (COI) gene sequences. Distribution The distribution of ''Limacina rangii'' is circumglobal south of 50°S. This species occurs in the Weddell Sea and Ross Sea in the Antarctic and in Cumberland Bay, South Georgia. and other localities in the Southern Ocean. Description ''Limacina ran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animal
Animals are multicellular, eukaryotic organisms in the Kingdom (biology), biological kingdom Animalia. With few exceptions, animals Heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, are Motility, able to move, can Sexual reproduction, reproduce sexually, and go through an ontogenetic stage in which their body consists of a hollow sphere of Cell (biology), cells, the blastula, during Embryogenesis, embryonic development. Over 1.5 million Extant taxon, living animal species have been Species description, described—of which around 1 million are Insecta, insects—but it has been estimated there are over 7 million animal species in total. Animals range in length from to . They have Ecology, complex interactions with each other and their environments, forming intricate food webs. The scientific study of animals is known as zoology. Most living animal species are in Bilateria, a clade whose members have a Symmetry in biology#Bilate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pelagic
The pelagic zone consists of the water column of the open ocean, and can be further divided into regions by depth (as illustrated on the right). The word ''pelagic'' is derived . The pelagic zone can be thought of as an imaginary cylinder or water column between the surface of the sea and the bottom. Conditions in the water column change with depth: pressure increases; temperature and light decrease; salinity, oxygen, micronutrients (such as iron, magnesium and calcium) all change. Marine life is affected by bathymetry (underwater topography) such as the seafloor, shoreline, or a submarine seamount, as well as by proximity to the boundary between the ocean and the atmosphere at the ocean surface, which brings light for photosynthesis, predation from above, and wind stirring up waves and setting currents in motion. The pelagic zone refers to the open, free waters away from the shore, where marine life can swim freely in any direction unhindered by topographical constraints. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytoplankton
Phytoplankton () are the autotrophic (self-feeding) components of the plankton community and a key part of ocean and freshwater ecosystems. The name comes from the Greek words (), meaning 'plant', and (), meaning 'wanderer' or 'drifter'. Phytoplankton obtain their energy through photosynthesis, as do trees and other plants on land. This means phytoplankton must have light from the sun, so they live in the well-lit surface layers (euphotic zone) of oceans and lakes. In comparison with terrestrial plants, phytoplankton are distributed over a larger surface area, are exposed to less seasonal variation and have markedly faster turnover rates than trees (days versus decades). As a result, phytoplankton respond rapidly on a global scale to climate variations. Phytoplankton form the base of marine and freshwater food webs and are key players in the global carbon cycle. They account for about half of global photosynthetic activity and at least half of the oxygen production, despite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Krill
Krill are small crustaceans of the order Euphausiacea, and are found in all the world's oceans. The name "krill" comes from the Norwegian Norwegian, Norwayan, or Norsk may refer to: *Something of, from, or related to Norway, a country in northwestern Europe * Norwegians, both a nation and an ethnic group native to Norway * Demographics of Norway *The Norwegian language, including ... word ', meaning "small fry of fish", which is also often attributed to species of fish. Krill are considered an important trophic level connection – near the bottom of the food chain. They feed on phytoplankton and (to a lesser extent) zooplankton, yet also are the main source of food for many larger animals. In the Southern Ocean, one species, the Antarctic krill, ''Euphausia superba'', makes up an estimated biomass (ecology), biomass of around 379,000,000 tonnes, making it among the species with the largest total biomass. Over half of this biomass is eaten by whales, Pinniped, seals, pen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holoplankton
Holoplankton are organisms that are plankton, planktic (they live in the water column and cannot swim against a current) for their entire life cycle. Holoplankton can be contrasted with meroplankton, which are planktic organisms that spend part of their life cycle in the benthic zone. Examples of holoplankton include some diatoms, radiolarians, some dinoflagellates, foraminifera, amphipods, krill, copepods, and salps, as well as some gastropod mollusk species. Holoplankton dwell in the pelagic zone as opposed to the benthic zone. Holoplankton include both phytoplankton and zooplankton and vary in size. The most common plankton are protists. Reproduction Holoplankton have unique traits that make reproduction in the water column possible. Both Sexual reproduction, sexual and Asexual reproduction, asexual reproduction are used depending on the type of plankton. Some invertebrate holoplankton release sperm into the water column which are then taken up by the females for fertilization ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limacina Antarctica Shell 2
''Limacina'' is a genus of swimming predatory sea snails commonly known as sea butterflies in the family Limacinidae. This genus contains some of the world's most abundant gastropod species.Bouchet, P.; Gofas, S. (2012). Limacina. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=138122 on 2012-07-18 Etymological meaning of the generic name ''Limacina'' is "snail-like". As pelagic marine gastropods, ''Limacina'' swim by flapping their parapodia, inspiring the common name sea butterflies. Sea butterflies are part of the clade Thecosomata. Sea angels, similar to ''Limacina'', are in the order Gymnosomata. Both of these orders are still referred to as "pteropods". Sea butterflies of the order Thecosomata have a shell, while sea angels in the order Gymnosomata do not. Shell description The shells of ''Limacina'' are well developed, sinistrally coiled, turret-like, and include an operculum. Shell size and thickness va ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limacina Antarctica Shell
''Limacina'' is a genus of swimming predatory sea snails commonly known as sea butterflies in the family Limacinidae. This genus contains some of the world's most abundant gastropod species.Bouchet, P.; Gofas, S. (2012). Limacina. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=138122 on 2012-07-18 Etymological meaning of the generic name ''Limacina'' is "snail-like". As pelagic marine gastropods, ''Limacina'' swim by flapping their parapodia, inspiring the common name sea butterflies. Sea butterflies are part of the clade Thecosomata. Sea angels, similar to ''Limacina'', are in the order Gymnosomata. Both of these orders are still referred to as "pteropods". Sea butterflies of the order Thecosomata have a shell, while sea angels in the order Gymnosomata do not. Shell description The shells of ''Limacina'' are well developed, sinistrally coiled, turret-like, and include an operculum. Shell size and thickness va ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southern Ocean
The Southern Ocean, also known as the Antarctic Ocean, comprises the southernmost waters of the World Ocean, generally taken to be south of 60° S latitude and encircling Antarctica. With a size of , it is regarded as the second-smallest of the five principal oceanic divisions: smaller than the Pacific, Atlantic, and Indian oceans but larger than the Arctic Ocean. Over the past 30 years, the Southern Ocean has been subject to rapid climate change, which has led to changes in the marine ecosystem. By way of his voyages in the 1770s, James Cook proved that waters encompassed the southern latitudes of the globe. Since then, geographers have disagreed on the Southern Ocean's northern boundary or even existence, considering the waters as various parts of the Pacific, Atlantic, and Indian oceans, instead. However, according to Commodore John Leech of the International Hydrographic Organization (IHO), recent oceanographic research has discovered the importance of Southern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Georgia Island
South Georgia ( es, Isla San Pedro) is an island in the South Atlantic Ocean that is part of the British Overseas Territory of South Georgia and the South Sandwich Islands. It lies around east of the Falkland Islands. Stretching in the east–west direction, South Georgia is around long and has a maximum width of . The terrain is mountainous, with the central ridge rising to at Mount Paget. The northern coast is indented with numerous bays and fjords, serving as good harbours. Discovered by Europeans in 1675, South Georgia had no indigenous population due to its harsh climate and remoteness. Captain James Cook in made the first landing, survey and mapping of the island, and on 17 January 1775 he claimed it a British possession, naming it "Isle of Georgia" after King George III. Through its history, it served as a whaling and seal hunting base, with intermittent population scattered in several whaling bases, the most important historically being Grytviken. The main settleme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cumberland Bay
Cumberland Bay is a bay, wide at its entrance between Larsen Point and Barff Point, which separates into two extensive arms, Cumberland West Bay and Cumberland East Bay, which recede inland along the northern coast of South Georgia. It was discovered and named in 1775 by a British expedition under James Cook. In the Second World War the whaling stations were closed except Grytviken and Leith Harbour. Most of the British and Norwegian whalers and factory ships were destroyed by German merchant raiders, and the remainder were called up to serve under Allied command. The resident British Magistrates (W. Barlas and A.I. Fleuret) attended to the island's defence throughout the War. The Royal Navy deployed the armed merchant cruiser to patrol South Georgian and Antarctic waters, and deployed two four-inch guns to protect key approaches: at Grytviken to protect Cumberland Bay and at Leith Harbour to protect Stromness Bay Stromness Bay is a bay wide, entered between Cape ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ross Sea
The Ross Sea is a deep bay of the Southern Ocean in Antarctica, between Victoria Land and Marie Byrd Land and within the Ross Embayment, and is the southernmost sea on Earth. It derives its name from the British explorer James Clark Ross who visited this area in 1841. To the west of the sea lies Ross Island and Victoria Land, to the east Roosevelt Island and Edward VII Peninsula in Marie Byrd Land, while the southernmost part is covered by the Ross Ice Shelf, and is about from the South Pole. Its boundaries and area have been defined by the New Zealand National Institute of Water and Atmospheric Research as having an area of . The circulation of the Ross Sea is dominated by a wind-driven ocean gyre and the flow is strongly influenced by three submarine ridges that run from southwest to northeast. The circumpolar deep water current is a relatively warm, salty and nutrient-rich water mass that flows onto the continental shelf at certain locations. The Ross Sea is covered with ice ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weddell Sea
The Weddell Sea is part of the Southern Ocean and contains the Weddell Gyre. Its land boundaries are defined by the bay formed from the coasts of Coats Land and the Antarctic Peninsula. The easternmost point is Cape Norvegia at Princess Martha Coast, Queen Maud Land. To the east of Cape Norvegia is the King Haakon VII Sea. Much of the southern part of the sea is covered by a permanent, massive ice shelf field, the Filchner-Ronne Ice Shelf. The sea is contained within the two overlapping Antarctic territorial claims of Argentine Antarctica, the British Antarctic Territory, and also resides partially within the Antarctic Chilean Territory. At its widest the sea is around across, and its area is around . Various ice shelves, including the Filchner-Ronne Ice Shelf, fringe the Weddell sea. Some of the ice shelves on the east side of the Antarctic Peninsula, which formerly covered roughly of the Weddell Sea, had completely disappeared by 2002. The Weddell Sea has been deemed by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
