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Scottnema
''Scottnema lindsayae'' is a species of nematode belonging to the family Cephalobidae. First described in 1971, it is endemic to Antarctica and most commonly found in the McMurdo Dry Valleys. ''S. lindsayae'', a microscopic worm, feeds on microbes, including bacteria, yeast, and algae. Adapted to very cold and dry climates, its population may be decreasing as a result of climate change. Taxonomy ''S. lindsayae'' is the only described member of ''Scottnema''. Originally described by R. W. Timm (1971), it was named after the polar explorer Robert Scott and the collector of the holotype specimen, Kay Lindsay. Description and lifecycle ''S. lindsayae'' is between half a millimeter and a millimeter in length and between two and four micrometers in width. ''S. lindsayae'' reproduces sexually, with females laying eggs. The minimum observed lifecycle length at is 218 days, with four juvenile stages outside of the egg. As it enters hibernation during Antarctic winters, ''S. lindsay ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cephalobidae
Cephalobidae is a family of nematodes belonging to the order Rhabditida Rhabditida is an order of free-living, parasitic and microbivorous nematodes living in soil. The Cephalobidae, Panagrolaimidae, Steinernematidae, and Strongyloididae seem to be closer to the Tylenchia, regardless of whether these are merg .... Genera Genera: * '' Acrobeles'' von Linstow, 1877 * '' Acrobeloides'' Cobb, 1924 * '' Scottnema'' Timm, 1971 References {{Taxonbar, from=Q5266809 Rhabditida Nematode families ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nematode
The nematodes ( or ; ; ), roundworms or eelworms constitute the phylum Nematoda. Species in the phylum inhabit a broad range of environments. Most species are free-living, feeding on microorganisms, but many are parasitic. Parasitic worms (helminths) are the cause of soil-transmitted helminthiases. They are classified along with arthropods, tardigrades and other moulting animals in the clade Ecdysozoa. Unlike the flatworms, nematodes have a tubular digestive system, with openings at both ends. Like tardigrades, they have a reduced number of Hox genes, but their sister phylum Nematomorpha has kept the ancestral protostome Hox genotype, which shows that the reduction has occurred within the nematode phylum. Nematode species can be difficult to distinguish from one another. Consequently, estimates of the number of nematode species are uncertain. A 2013 survey of animal biodiversity suggested there are over 25,000. Estimates of the total number of extant species are su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species Description
A species description is a formal scientific description of a newly encountered species, typically articulated through a scientific publication. Its purpose is to provide a clear description of a new species of organism and explain how it differs from species that have been previously described or related species. For a species to be considered valid, a species description must follow established guidelines and naming conventions dictated by relevant nomenclature codes. These include the International Code of Zoological Nomenclature (ICZN) for animals, the International Code of Nomenclature for algae, fungi, and plants (ICN) for plants, and the International Committee on Taxonomy of Viruses (ICTV) for viruses. A species description often includes photographs or other illustrations of type material and information regarding where this material is deposited. The publication in which the species is described gives the new species a formal scientific name. Some 1.9 million ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endemism
Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, the Cape sugarbird is found exclusively in southwestern South Africa and is therefore said to be ''endemic'' to that particular part of the world. An endemic species can also be referred to as an ''endemism'' or, in scientific literature, as an ''endemite''. Similarly, many species found in the Western ghats of India are examples of endemism. Endemism is an important concept in conservation biology for measuring biodiversity in a particular place and evaluating the risk of extinction for species. Endemism is also of interest in evolutionary biology, because it provides clues about how changes in the environment cause species to undergo range shifts (potentially expanding their range into a larger area or b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
McMurdo Dry Valleys
The McMurdo Dry Valleys are a row of largely Antarctic oasis, snow-free valleys in Antarctica, located within Victoria Land west of McMurdo Sound. The Dry Valleys experience extremely low humidity and surrounding mountains prevent the flow of ice from nearby glaciers. The rocks there are granites and gneisses, and glacial tills dot this bedrock landscape, with loose gravel covering the ground. It is one of the driest places on Earth, though there are several anecdotal accounts of rainfall within the Dry Valleys. The region is one of the world's most extreme deserts, and includes many features including Lake Vida, a saline lake, and the Onyx River, a meltwater stream and Antarctica's longest river. Although no living organisms have been found in the permafrost here, Endolithic lichen, endolithic Photosynthesis, photosynthetic bacteria have been found living in the relatively moist interior of rocks, and anaerobic bacteria, with a metabolism based on iron and sulfur, live under ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Climate Change
Present-day climate change includes both global warming—the ongoing increase in Global surface temperature, global average temperature—and its wider effects on Earth's climate system. Climate variability and change, Climate change in a broader sense also includes previous long-term changes to Earth's climate. The current rise in global temperatures is Scientific consensus on climate change, driven by human activities, especially fossil fuel burning since the Industrial Revolution. Fossil fuel use, Deforestation and climate change, deforestation, and some Greenhouse gas emissions from agriculture, agricultural and Environmental impact of concrete, industrial practices release greenhouse gases. These gases greenhouse effect, absorb some of the heat that the Earth Thermal radiation, radiates after it warms from sunlight, warming the lower atmosphere. Carbon dioxide, the primary gas driving global warming, Carbon dioxide in Earth's atmosphere, has increased in concentratio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robert Falcon Scott
Captain Robert Falcon Scott (6 June 1868 – ) was a British Royal Navy officer and explorer who led two expeditions to the Antarctic regions: the Discovery Expedition, ''Discovery'' expedition of 1901–04 and the Terra Nova Expedition, ''Terra Nova'' expedition of 1910–13. On the first expedition, he set a new southern record by marching to latitude 82°S and discovered the Antarctic Plateau, on which the South Pole is located. On the second venture, Scott led a party of five which reached the South Pole on 17 January 1912, less than five weeks after Amundsen's South Pole expedition. On the return journey from the Pole, a planned meeting with supporting dog teams from the base camp failed, despite Scott's written instructions, and at a distance of from their base camp at Hut Point and approximately from the next depot, Scott and his companions died. When Scott and his party's bodies were discovered, they had in their possession the first Antarctic fossils discovere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holotype
A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several examples, but explicitly designated as the holotype. Under the International Code of Zoological Nomenclature (ICZN), a holotype is one of several kinds of name-bearing types. In the International Code of Nomenclature for algae, fungi, and plants (ICN) and ICZN, the definitions of types are similar in intent but not identical in terminology or underlying concept. For example, the holotype for the butterfly '' Plebejus idas longinus'' is a preserved specimen of that subspecies, held by the Museum of Comparative Zoology at Harvard University. In botany and mycology, an isotype is a duplicate of the holotype, generally pieces from the same individual plant or samples from the same genetic individual. A holotype is not necessarily "ty ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micrometre
The micrometre (English in the Commonwealth of Nations, Commonwealth English as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American English), also commonly known by the non-SI term micron, is a unit of length in the International System of Units (SI) equalling (SI standard prefix "micro-" = ); that is, one millionth of a metre (or one thousandth of a millimetre, , or about ). The nearest smaller common SI Unit, SI unit is the nanometre, equivalent to one thousandth of a micrometre, one millionth of a millimetre or one billionth of a metre (). The micrometre is a common unit of measurement for wavelengths of infrared radiation as well as sizes of biological cell (biology), cells and bacteria, and for grading wool by the diameter of the fibres. The width of a single human hair ranges from approximately 20 to . Examples Between 1 μm and 10 μm: * 1–10 μm – length of a typical bacterium * 3–8 μm – width of str ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
McMurdo Dry Valleys From Antarctic Topographic Reconnaissance Maps (USGS-NSF)
Vice-Admiral Archibald William McMurdo (24 September 1812 – 11 December 1875) was a Scottish naval officer and polar explorer after whom Antarctica's McMurdo Sound, McMurdo Station, McMurdo Ice Shelf, McMurdo Dry Valleys and McMurdo–South Pole Highway are named. Early life Archibald William McMurdo was born on 24 September 1812 in Scotland. He was the son of Lieutenant Colonel Archibald McMurdo and grandson of John McMurdo, a chamberlain at Drumlanrig Castle. Career McMurdo joined the Royal Navy on 6 October 1824, at the age of 12. He was promoted to lieutenant in 1836 for his skill and courage in saving the crew of a shipwrecked whaler from hostile New Zealand natives. He achieved the rank of commander in 1843 and captain in 1851. His career included two discovery expeditions aboard HMS ''Terror'', the first to Hudson Bay (1836–1837), the second to Antarctica (1839–1842). In 1836 he served on HMS ''Volage'' during its voyage to East India. During the Antarctic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
East Ongul Island
East Ongul Island is an island in the Flatvaer Islands off of Antarctica. It is long, lying immediately east of the northern part of Ongul Island at the east side of the entrance of Lutzow-Holm Bay. East Ongul Island this island was originally mapped as a part of Ongul Island by Norwegian cartographers who worked from air photos taken by the Lars Christensen Expedition (LCE), 1936–37. In 1957, the Japanese Antarctic Research Expedition (JARE) discovered the Nakano-seto Strait, a small strait separating Ongul and East Ongul islands. The name Ongul Island was retained for the largest island in the group, and the smaller island was given the name East Ongul Island. Showa Station, a Japanese permanent research station, was built on East Ongul Island in 1957. Named features Both the Lars Christensen Expedition (LCE) and the later Japanese Antarctic Research Expedition (JARE) mapped and named many features on and around East Ongul Island. Unless noted below, all names were app ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Admiralty Bay (South Shetland Islands)
Admiralty Bay is an irregular bay, wide at its entrance between Demay Point and Martins Head, indenting the southern coast of King George Island for , in the South Shetland Islands of Antarctica. The name appears on a map of 1822 by Captain George Powell, a British sailor, and is now established in international usage. The Henryk Arctowski Polish Antarctic Station is situated on the bay, as is the Comandante Ferraz Brazilian Antarctic Base. It has been designated an Antarctic Specially Managed Area (ASMA 1). Description The bay has three fjords: Martel, Mackellar, and Ezcurra. A mariner's guide to the region pronounced the bay to have the best anchorage of any in the South Shetlands, "being well-sheltered all around and having moderate depths over a bottom of good, stiff clay. Ice from the glaciers is frequently troublesome." Chilean scientists have claimed that Amerinds visited the area, due to stone artifacts recovered from bottom-sampling operations in the bay. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
