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Polysticta
Steller's eider (''Polysticta stelleri'') is a migrating Arctic diving duck that breeds along the coastlines of eastern Russia and Alaska. It is the rarest, smallest, and fastest flying of the eider species. Due to the extensive contraction of its breeding range, the Alaska-breeding population of Steller's eider was listed as vulnerable in 1997 by the International Union for the Conservation of Nature (International Union for Conservation of Nature, IUCN). The species is protected in Russia and the U.S. and is the subject of an ongoing recovery plan by the European Union and United States Fish and Wildlife Service, U.S. Fish and Wildlife Service. Taxonomy Steller's eider was Species description, formally described and illustrated in 1769 by the German naturalist Peter Simon Pallas from a specimen collected on the Kamchatka Peninsula in Eastern Russia. He coined the binomial name ''Anas stelleri''; the specific epithet was chosen to honour the German naturalist and explorer Geo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Georg Wilhelm Steller
Georg Wilhelm Steller (10 March 1709 – 14 November 1746) was a German-born naturalist and explorer who contributed to the fields of biology, zoology, and ethnography. He participated in the Great Northern Expedition (1733–1743) and his observations of the natural world helped the exploration and documentation of the flora and fauna of the North Pacific region. Steller pursued studies in theology and medicine before turning his attention to the natural sciences. In 1734, he joined the Russian Academy of Sciences as a physician, eventually being selected to accompany Bering's expedition to the uncharted waters between Siberia and North America. Steller kept detailed records of species and cultures encountered, as well as ocean currents during the journey. Steller discovered many new species, as he documented numerous plants and animals, many of which were previously unknown to Western science. Notable among his discoveries was the Steller's sea cow and Steller's sea eagle. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Labrador Duck
The Labrador duck (''Camptorhynchus labradorius'') is an extinct North American duck species. It has the distinction of being the first known endemic North American bird species to become extinct after the Columbian Exchange, with the last reported sighting occurring in 1878 in Elmira, New York, and the last preserved specimen was shot in the fall of 1875 in Long Island, New York by J.G. Bell. It was already a rare duck before European settlers arrived, and as a result of its rarity, information on the Labrador duck is not abundant, although some, such as its habitat, characteristics, dietary habits and reasons behind its extinction, are known. There are 55 specimens of the Labrador duck preserved in museum collections worldwide. Taxonomy The Labrador duck was also known as the pied duck and skunk duck, the former being a vernacular name that it shared with the surf scoter and the common goldeneye (and even the American oystercatcher), a fact that has led to difficulties in int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eider
The eiders () are large seaducks in the genus ''Somateria''. The three extant species all breed in the cooler latitudes of the Northern Hemisphere. The down feathers of eider ducks and some other ducks and geese are used to fill pillows and quilts—they have given the name to the type of quilt known as an eiderdown. Taxonomy The genus ''Somateria '' was introduced in 1819 to accommodate the king eider by the English zoologist William Leach in an appendix to John Ross's account of his voyage to look for the Northwest Passage. The name is derived from Ancient Greek : ''sōma'' "body" (stem ''somat-'') and : ''erion'' "wool", referring to eiderdown. Steller's eider (''Polysticta stelleri'') is in a different genus despite its name. Species The genus contains three extant species. Two undescribed species are known from fossils, one from Middle Oligocene rocks in Kazakhstan and another from the Late Miocene or Early Pliocene of Lee Creek Mine, United States. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crustacean
Crustaceans (from Latin meaning: "those with shells" or "crusted ones") are invertebrate animals that constitute one group of arthropods that are traditionally a part of the subphylum Crustacea (), a large, diverse group of mainly aquatic arthropods including decapods (shrimps, prawns, crabs, lobsters and crayfish), seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, opossum shrimps, amphipods and mantis shrimp. The crustacean group can be treated as a subphylum under the clade Mandibulata. It is now well accepted that the hexapods (insects and entognathans) emerged deep in the Crustacean group, with the completed pan-group referred to as Pancrustacea. The three classes Cephalocarida, Branchiopoda and Remipedia are more closely related to the hexapods than they are to any of the other crustaceans ( oligostracans and multicrustaceans). The 67,000 described species range in size from '' Stygotantulus stocki'' at , to the Japanese ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tundra
In physical geography, a tundra () is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. There are three regions and associated types of tundra: #Arctic, Arctic, Alpine tundra, Alpine, and #Antarctic, Antarctic. Tundra vegetation is composed of dwarf shrubs, Cyperaceae, sedges, Poaceae, grasses, mosses, and lichens. Scattered trees grow in some tundra regions. The ecotone (or ecological boundary region) between the tundra and the forest is known as the tree line or timberline. The tundra soil is rich in nitrogen and phosphorus. The soil also contains large amounts of biomass and decomposed biomass that has been stored as methane and carbon dioxide in the permafrost, making the tundra soil a carbon sink. As global warming heats the ecosystem and causes soil thawing, the permafrost carbon cycle accelerates and releases much of these soil-contained greenhouse gases into the atmosphere, creating Climate change feedback, a feedback cycle t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carex Aquatilis
''Carex aquatilis'' is a species of Carex, sedge known as water sedge and leafy tussock sedge. It has a Circumboreal Region, circumboreal distribution, occurring throughout the northern reaches of the Northern Hemisphere. It grows in many types of mountainous and arctic habitat, including temperate coniferous forest, alpine tundra, alpine meadows, tundra, and wetlands. There are several varieties of this species, and it is somewhat variable in appearance. It produces triangular stems reaching heights between and , and generally does not form clumps as some other sedges do. It grows from a dense rhizome network which produces a mat of fine roots thick enough to form sod, and includes aerenchyma to allow the plant to survive in low-oxygen substrates like heavy mud. The inflorescence bears a number of spikes with one leaflike bract at the base which is longer than the inflorescence itself. The fruits are glossy achenes, and although the plant occasionally reproduces by seed, most of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctophila Fulva
''Dupontia fulva'', commonly known as pendant grass, is a species of grass native to arctic and subarctic regions of Eurasia and North America (northern Russia, Finland, Sweden, Svalbard, Greenland, Alaska, and Canada), where it grows in tundra wetlands. See also *List of Poaceae genera
Poaceae, also known as the true grasses, is the fourth largest plant family in the world with around 12,000 species and roughly 800 genera. They contain, among others, the cereal crop species and other plants of economic importance, such ...
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Thomas Campbell Eyton
Thomas Campbell Eyton JP, DL (10 September 1809 – 25 October 1880) was an English naturalist whose fields were cattle, fishes and birds. He was a friend and correspondent of Charles Darwin though he opposed his theories. Eyton was born at Eyton Hall, near Wellington, Shropshire. He studied at St John's College, Cambridge, where he was a contemporary and friend of Charles Darwin. After succeeding to the estate in 1855, Eyton built a large natural history museum at Eyton Hall that included a range of bird skins and skeletons, described as "one of the finest in Europe". Besides Darwin, Eyton enjoyed some correspondence with other naturalists including Louis Agassiz, Asa Gray, and Alfred Russel Wallace. Eyton published ''History of the Rarer British Birds'' (1836), ''A Monograph on the Anatidae, Or Duck Tribe'' (1838), ''A History of Oyster and Oyster Fisheries'' (1858) and ''Osteologia Avium'' (1871–78). He established in about 1842 the ''Herd Book of Hereford Cattle'', wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bird Measurement
Bird measurement or bird biometrics are approaches to quantify the size of birds in scientific studies. The variation in dimensions and weights across birds is one of the fundamental sources of diversity among birds, and even Within species, dimensions may vary across populations Intraspecific variability, within species, between the sexes and depending on Biomarkers of aging, age and condition. For measurements to be useful, they must be well-defined to be consistent and comparable with those taken by others or at other points in time. Measurements can be useful to identify species, quantify functional and ecomorphology, ecomorphological differences, study growth, variation between geographically separated forms, identify Sexual dimorphism measures, differences between the sexes, age or otherwise characterize individual birds. While certain measurements are regularly taken to study living birds, others apply only to specimens in bird collections or are measurable only in the labo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Capelin
The capelin or caplin (''Mallotus villosus'') is a small forage fish of the smelt family found in the North Atlantic, North Pacific and Arctic oceans. In summer, it grazes on dense swarms of plankton at the edge of the ice shelf. Larger capelin also eat a great deal of krill and other crustaceans. Among others, whales, seals, Atlantic cod, Atlantic mackerel, squid and seabirds prey on capelin, in particular during the spawning season while the capelin migrate south. Capelin spawn on sand and gravel bottoms or sandy beaches at the age of two to six years. When spawning on beaches, capelin have an extremely high post-spawning mortality rate which, for males, is close to 100%. Males reach in length, while females are up to long. They are olive-coloured dorsally, shading to silver on sides. Males have a translucent ridge on both sides of their bodies. The ventral aspects of the males iridesce reddish at the time of spawn. The closest relative of the capelin appears to have be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mollusca
Mollusca is a phylum of protostome, protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant taxon, extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The number of additional fossil species is estimated between 60,000 and 100,000, and the proportion of undescribed species is very high. Many taxa remain poorly studied. Molluscs are the largest marine biology, marine phylum, comprising about 23% of all the named marine organisms. They are highly diverse, not just in size and anatomical structure, but also in behaviour and habitat, as numerous groups are freshwater mollusc, freshwater and even terrestrial molluscs, terrestrial species. The phylum is typically divided into 7 or 8 taxonomy (biology), taxonomic class (biology), classes, of which two are entirely extinct. Cephalopod molluscs, such as squid, cuttlefish, and octopuses, are among the most neurobiology, neurologi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
