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Argyropelecus Olfersii
''Argyropelecus olfersii'' is a common species of marine hatchetfish, found in mesopelagic waters. Discovery and naming ''Argyropelecus olfersii'' was described by Georges Cuvier in Chapter 27 of '' Histoire Naturelle des Poissons'', based on specimens held in the National Museum of Natural History in Paris and the Natural History Museum, Berlin. The specific name honours the German diplomat and natural historian Ignaz von Olfers, who presented the Berlin specimen to the museum upon his return from a diplomatic excursion to Brazil. Distribution and habitat ''A. olfersii'' is found in temperate waters worldwide, with a preferred temperature range of 5.1-13.3°C. The fish is present in all oceans save the Southern, however records are rare from the Indian Ocean. During daylight hours, subadult and adult fish live at depths of 200-800m, undergoing a vertical migration to 100-600m at sunset. Description Like other members of the subfamily Sternoptychinae, ''Argyropelecus'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Georges Cuvier
Jean Léopold Nicolas Frédéric, Baron Cuvier (; 23 August 1769 – 13 May 1832), known as Georges Cuvier, was a French naturalist and zoologist, sometimes referred to as the "founding father of paleontology". Cuvier was a major figure in natural sciences research in the early 19th century and was instrumental in establishing the fields of comparative anatomy and paleontology through his work in comparing living animals with fossils. Cuvier's work is considered the foundation of vertebrate paleontology, and he expanded Linnaean taxonomy by grouping classes into phylum, phyla and incorporating both fossils and living species into the classification. Cuvier is also known for establishing extinction as a fact—at the time, extinction was considered by many of Cuvier's contemporaries to be merely controversial speculation. In his ''Essay on the Theory of the Earth'' (1813) Cuvier proposed that now-extinct species had been wiped out by periodic catastrophic flooding events. In th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diel Vertical Migration
Diel vertical migration (DVM), also known as diurnal vertical migration, is a pattern of movement used by some organisms, such as copepods, living in the ocean and in lakes. The word ''diel'' comes from the Latin ''dies'' day, and means a 24-hour period. The migration occurs when organisms move up to the uppermost layer of the sea at night and return to the bottom of the daylight zone of the oceans or to the dense, bottom layer of lakes during the day. It is important to the functioning of deep-sea food webs and the biologically driven sequestration of carbon. In terms of biomass, it is the largest synchronous migration in the world. It is not restricted to any one taxon as examples are known from crustaceans (copepods), molluscs ( squid), and ray-finned fishes (trout). The phenomenon may be advantageous for a number of reasons, most typically to access food and avoid predators. It is triggered by various stimuli, the most prominent being response to changes in ligh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sternoptychidae
The marine hatchetfishes or deep-sea hatchetfishes as well as the related bottlelights, pearlsides and constellationfishes are small deep-sea ray-finned fish of the stomiiform family Sternoptychidae. They are not closely related to and should not be confused with the freshwater hatchetfishes, which are teleosts in the characiform family Gasteropelecidae. The Sternoptychidae have 10 genera and about 70 species altogether.Nelson (2006): p.209 The scientific name means "''Sternoptyx''-family", from ''Sternoptyx'' (the type genus) + the standard animal family suffix "-idae". The type genus derives from Ancient Greek ''stérnon'' (στέρνον, "breast") + ''ptýx'' (πτύξ, "a fold/crease") + Latin ''forma'' ("external form"), the Greek part in reference to the thorax shape of marine hatchetfishes. Description and ecology Found most often at depths of 200–600 meters in tropical, subtropical and temperate waters of the Atlantic, Pacific and Indian Oceans, marine hatchetfi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bay Of Biscay
The Bay of Biscay (), known in Spain as the Gulf of Biscay ( es, Golfo de Vizcaya, eu, Bizkaiko Golkoa), and in France and some border regions as the Gulf of Gascony (french: Golfe de Gascogne, oc, Golf de Gasconha, br, Pleg-mor Gwaskogn), is a gulf of the northeast Atlantic Ocean located south of the Celtic Sea. It lies along the western coast of France from Point Penmarc'h to the Spanish border, and the northern coast of Spain west to Cape Ortegal. The south area of the Bay of Biscay that washes over the northern coast of Spain is known locally as the Cantabrian Sea. The average depth is and the greatest depth is . Name The Bay of Biscay is named (for English speakers) after Biscay on the northern Spanish coast, probably standing for the western Basque districts (''Biscay'' up to the early 19th century). Its name in other languages is: * ast, Mar Cantábricu * eu, Bizkaiko golkoa * br, pleg-mor Gwaskogn * french: golfe de Gascogne (named after Gascony, France) * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Halocarbon
Halocarbon compounds are chemicals in which one or more carbon atoms are linked by covalent bonds with one or more halogen atoms ( fluorine, chlorine, bromine or iodine – ) resulting in the formation of organofluorine compounds, organochlorine compounds, organobromine compounds, and organoiodine compounds. Chlorine halocarbons are the most common and are called organochlorides. Many synthetic organic compounds such as plastic polymers, and a few natural ones, contain halogen atoms; they are known as ''halogenated'' compounds or ''organohalogens''. Organochlorides are the most common industrially used organohalides, although the other organohalides are used commonly in organic synthesis. Except for extremely rare cases, organohalides are not produced biologically, but many pharmaceuticals are organohalides. Notably, many pharmaceuticals such as Prozac have trifluoromethyl groups. For information on inorganic halide chemistry, see halide. Chemical families Halocarbons ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Feedback
Feedback occurs when outputs of a system are routed back as inputs as part of a chain of cause-and-effect that forms a circuit or loop. The system can then be said to ''feed back'' into itself. The notion of cause-and-effect has to be handled carefully when applied to feedback systems: History Self-regulating mechanisms have existed since antiquity, and the idea of feedback had started to enter economic theory in Britain by the 18th century, but it was not at that time recognized as a universal abstraction and so did not have a name. The first ever known artificial feedback device was a float valve, for maintaining water at a constant level, invented in 270 BC in Alexandria, Egypt. This device illustrated the principle of feedback: a low water level opens the valve, the rising water then provides feedback into the system, closing the valve when the required level is reached. This then reoccurs in a circular fashion as the water level fluctuates. Centrifugal governors we ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photophore
A photophore is a glandular organ that appears as luminous spots on various marine animals, including fish and cephalopods. The organ can be simple, or as complex as the human eye; equipped with lenses, shutters, color filters and reflectors, however unlike an eye it is optimized to produce light, not absorb it. The bioluminescence can variously be produced from compounds during the digestion of prey, from specialized mitochondrial cells in the organism called photocytes ("light producing" cells), or, similarly, associated with symbiotic bacteria in the organism that are cultured. The character of photophores is important in the identification of deep sea fishes. Photophores on fish are used for attracting food or for camouflage from predators by counter-illumination. Photophores are found on some cephalopods including the firefly squid, which can create impressive light displays, as well as numerous other deep sea organisms such as the pocket shark Mollisquama mississipp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Counter-illumination
Counter-illumination is a method of active camouflage seen in marine animals such as firefly squid and midshipman fish, and in military prototypes, producing light to match their backgrounds in both brightness and wavelength. Marine animals of the mesopelagic (mid-water) zone tend to appear dark against the bright water surface when seen from below. They can camouflage themselves, often from predators but also from their prey, by producing light with bioluminescent photophores on their downward-facing surfaces, reducing the contrast of their silhouettes against the background. The light may be produced by the animals themselves, or by symbiotic bacteria, often '' Aliivibrio fischeri''. Counter-illumination differs from countershading, which uses only pigments such as melanin to reduce the appearance of shadows. It is one of the dominant types of aquatic camouflage, along with transparency and silvering. All three methods make animals in open water resemble their envir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indian Ocean
The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or ~19.8% of the water on Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by the Southern Ocean or Antarctica, depending on the definition in use. Along its core, the Indian Ocean has some large marginal or regional seas such as the Arabian Sea, Laccadive Sea, Bay of Bengal, and Andaman Sea. Etymology The Indian Ocean has been known by its present name since at least 1515 when the Latin form ''Oceanus Orientalis Indicus'' ("Indian Eastern Ocean") is attested, named after India, which projects into it. It was earlier known as the ''Eastern Ocean'', a term that was still in use during the mid-18th century (see map), as opposed to the ''Western Ocean'' ( Atlantic) before the Pacific was surmised. Conversely, Chinese explorers in the Indian Ocean during the 15th century called it the Western Oceans. In Anci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine Hatchetfish
Marine hatchetfishes or deep-sea hatchetfishes are small deep-sea mesopelagic ray-finned fish of the stomiiform subfamily Sternoptychinae. They should not be confused with the freshwater hatchetfishes, which are not particularly closely related Teleostei in the characiform family Gasteropelecidae. (2006): ''Fishes of the World'' (4th ed.). John Wiley & Sons, Inc. p.209 The scientific name means "''Sternoptyx''-subfamily", from ''Sternoptyx'' (the type genus) + the standard animal family suffix "-inae". It ultimately derives from Ancient Greek ''stérnon'' (στέρνον, "breast") + ''ptýx'' (πτύξ, "a fold/crease") + Latin ''forma'' ("external form"), the Greek part in reference to the thorax shape of marine hatchetfishes. (2006)Family Sternoptychidae Version of 2006-OCT-10. Retrieved 2009-OCT-02. Description and ecology Found in tropical, subtropical and temperate waters of the Atlantic, Pacific and Indian Oceans, marine hatchetfishes range in size from '' Polyipnu ... [...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 Southe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ignaz Von Olfers
Ignaz Franz Werner Maria von Olfers (30 August 1793 – 23 April 1871) was a German naturalist, historian and diplomat. Olfers was born in Münster. In 1816 he travelled to Brazil as a diplomat. In 1839 he was made director of the royal art collections and had significant influence on Frederick William IV of Prussia for a re-development of the Museumsinsel, Berlin. Together with architect Friedrich August Stueler, he developed the concept of the Neues Museum, Berlin and had great influence on organisation and presentation of exhibits and interior. His daughter was the writer and illustrator Marie von Olfers. Olfers described a number of new mammal species in Wilhelm Ludwig von Eschwege's ''Journal von Brasilien'' (1818). In 1819, '' Olfersia'' which is a genus of ferns (in the family Dryopteridaceae) from South America, was published, then a species of South American snake, ''Philodryas olfersii'' (in 1823),Beolens B, Watkins M, Grayson M (2011). ''The Eponym Dictionary of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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