Cookie Cutter Shark
The cookiecutter shark (''Isistius brasiliensis''), also called the cigar shark, is a species of small squaliform shark in the family Dalatiidae. This shark occurs in warm, oceanic waters worldwide, particularly near islands, and has been recorded as deep as . It migrates vertically up to every day, approaching the surface at dusk and descending with the dawn. Reaching only in length, the cookiecutter shark has a long, cylindrical body with a short, blunt snout, large eyes, two tiny spineless dorsal fins, and a large caudal fin. It is dark brown, with light-emitting photophores covering its underside except for a dark "collar" around its throat and gill slits. The name "cookiecutter shark" refers to its feeding habit of gouging round plugs, as if cut out with a cookie cutter, out of larger animals. Marks made by cookiecutter sharks have been found on a wide variety of marine mammals and fishes, as well as on submarines, undersea cables, and even human bodies. It also consume ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Jean René Constant Quoy
Jean René Constant Quoy (10 November 1790 in Maillé, Vendée, Maillé – 4 July 1869 in Rochefort, Charente-Maritime, Rochefort) was a French naval surgeon, zoologist and anatomist. In 1806, he began his medical studies at the school of naval medicine at Rochefort, Charente-Maritime, Rochefort, afterwards serving as an auxiliary-surgeon on a trip to the Antilles (1808–1809). After earning his medical doctorate in 1814 at Montpellier, he was surgeon-major on a journey to Réunion (1814–1815). Along with Joseph Paul Gaimard, he served as naturalist and surgeon aboard the ''Uranie'' under Louis de Freycinet from 1817 to 1820, and on the ''French ship Astrolabe (1817), Astrolabe'' (1826–1829) under the command of Jules Dumont d'Urville. In July 1823 he and Gaimard presented a paper to the Académie royale des Sciences on the origin of coral reefs, taking issue with the then widespread belief that these were constructed by coral polyps from bases in very deep water and arguin ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Adaptation
In biology, adaptation has three related meanings. Firstly, it is the dynamic evolutionary process of natural selection that fits organisms to their environment, enhancing their evolutionary fitness. Secondly, it is a state reached by the population during that process. Thirdly, it is a phenotypic trait or adaptive trait, with a functional role in each individual organism, that is maintained and has evolved through natural selection. Historically, adaptation has been described from the time of the ancient Greek philosophers such as Empedocles and Aristotle. In 18th and 19th century natural theology, adaptation was taken as evidence for the existence of a deity. Charles Darwin proposed instead that it was explained by natural selection. Adaptation is related to biological fitness, which governs the rate of evolution as measured by change in allele frequencies. Often, two or more species co-adapt and co-evolve as they develop adaptations that interlock with those of the oth ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Type Specimen
In biology, a type is a particular wiktionary:en:specimen, specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to anchor or centralizes the defining features of that particular taxon. In older usage (pre-1900 in botany), a type was a taxon rather than a specimen. A taxon is a scientifically named grouping of organisms with other like organisms, a set (mathematics), set that includes some organisms and excludes others, based on a detailed published description (for example a species description) and on the provision of type material, which is usually available to scientists for examination in a major museum research collection, or similar institution. Type specimen According to a precise set of rules laid down in the International Code of Zoological Nomenclature (ICZN) and the International Code of Nomenclature for algae, fungi, and plants (ICN), the ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Louis De Freycinet
Louis Claude de Saulces de Freycinet (7 August 1779 – 18 August 1841) was a French Navy officer. He circumnavigated the earth, and in 1811 published the first map to show a full outline of the coastline of Australia. Biography He was born at Montélimar, Drôme. Louis-Claude de Saulces de Freycinet was his full name (many calling him Louis de Freycinet). He had three brothers, Louis-Henri de Saulces de Freycinet, André-Charles de Saulces de Freycinet and the youngest, Frédéric-Casimir de Saulces de Freycinet (father of Charles de Freycinet). Louis-Claude was the second oldest. In 1793 he joined the French Navy as a midshipman, and took in several engagements against the British. In 1800, Freycinet was appointed to an exploration expedition to Southern and South-Western coasts of Australia under Nicolas Baudin, on ''Naturaliste'' and ''Géographe''. Freycinet's brother, Louis-Henri de Freycinet, was also part of the expedition. Between September 1802 and August 1803, Fre ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Corvette
A corvette is a small warship. It is traditionally the smallest class of vessel considered to be a proper (or " rated") warship. The warship class above the corvette is that of the frigate, while the class below was historically that of the sloop-of-war. The modern roles that a corvette fulfills include coastal patrol craft, missile boat and fast attack craft. These corvettes are typically between 500 tons and 2,000 .although recent designs may approach 3,000 tons, having size and capabilities that overlap with smaller frigates. However unlike contemporary frigates, a modern corvette does not have sufficient endurance and seaworthiness for long voyages. The word "corvette" is first found in Middle French, a diminutive of the Dutch word ''corf'', meaning a "basket", from the Latin ''corbis''. The rank "corvette captain", equivalent in many navies to "lieutenant commander", derives from the name of this type of ship. The rank is the most junior of three "captain" ranks in sev ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Fisheries
Fishery can mean either the enterprise of raising or harvesting fish and other aquatic life; or more commonly, the site where such enterprise takes place ( a.k.a. fishing ground). Commercial fisheries include wild fisheries and fish farms, both in freshwater waterbodies (about 10% of all catch) and the oceans (about 90%). About 500 million people worldwide are economically dependent on fisheries. 171 million tonnes of fish were produced in 2016, but overfishing is an increasing problem — causing declines in some populations. Because of their economic and social importance, fisheries are governed by complex fisheries management practices and legal regimes that vary widely across countries. Historically, fisheries were treated with a " first-come, first-served " approach, but recent threats by human overfishing and environmental issues have required increased regulation of fisheries to prevent conflict and increase profitable economic activity on the fishery. Modern jurisdicti ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Least Concern
A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. They do not qualify as threatened, near threatened, or (before 2001) conservation dependent. Species cannot be assigned the "Least Concern" category unless they have had their population status evaluated. That is, adequate information is needed to make a direct, or indirect, assessment of its risk of extinction based on its distribution or population status. Evaluation Since 2001 the category has had the abbreviation "LC", following the IUCN 2001 Categories & Criteria (version 3.1). Before 2001 "least concern" was a subcategory of the "Lower Risk" category and assigned the code "LR/lc" or lc. Around 20% of least concern taxa (3261 of 15636) in the IUCN database still use the code "LR/lc", which indicates they have not been re-evaluate ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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International Union For Conservation Of Nature
The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natural resources. It is involved in data gathering and analysis, research, field projects, advocacy, and education. IUCN's mission is to "influence, encourage and assist societies throughout the world to conserve nature and to ensure that any use of natural resources is equitable and ecologically sustainable". Over the past decades, IUCN has widened its focus beyond conservation ecology and now incorporates issues related to sustainable development in its projects. IUCN does not itself aim to mobilize the public in support of nature conservation. It tries to influence the actions of governments, business and other stakeholders by providing information and advice and through building partnerships. The organization is best known to the wider pu ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Shark Attack
A shark attack is an attack on a human by a shark. Every year, around 80 unprovoked attacks are reported worldwide. Despite their rarity, many people fear shark attacks after occasional serial attacks, such as the Jersey Shore shark attacks of 1916, and horror fiction and films such as the ''Jaws'' series. Out of more than 489 shark species, only three of them are responsible for a double-digit number of fatal, unprovoked attacks on humans: the great white, tiger, and bull.ISAStatistics on Attacking Species of Shark/ref> The oceanic whitetip has probably killed many more castaways, but these are not recorded in the statistics. Terminology While the term "shark attack" is in common use for instances of humans being wounded by sharks, it has been suggested that this is based largely on the assumption that large predatory sharks (such as great white, bull, and tiger sharks) only seek out humans as prey. A 2013 review recommends instances where a shark clearly predates on a huma ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Habitat
In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical manifestation of its ecological niche. Thus "habitat" is a species-specific term, fundamentally different from concepts such as environment or vegetation assemblages, for which the term "habitat-type" is more appropriate. The physical factors may include (for example): soil, moisture, range of temperature, and light intensity. Biotic factors will include the availability of food and the presence or absence of predators. Every species has particular habitat requirements, with habitat generalist species able to thrive in a wide array of environmental conditions while habitat specialist species requiring a very limited set of factors to survive. The habitat of a species is not necessarily found in a geographical area, it can be the interior ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Shoaling And Schooling
In biology, any group of fish that stay together for social reasons are shoaling, and if the group is swimming in the same direction in a coordinated manner, they are schooling. In common usage, the terms are sometimes used rather loosely. About one quarter of fish species shoal all their lives, and about one half shoal for part of their lives. Fish derive many benefits from shoaling behaviour including defence against predators (through better predator detection and by diluting the chance of individual capture), enhanced foraging success, and higher success in finding a mate. It is also likely that fish benefit from shoal membership through increased hydrodynamic efficiency. Fish use many traits to choose shoalmates. Generally they prefer larger shoals, shoalmates of their own species, shoalmates similar in size and appearance to themselves, healthy fish, and kin (when recognized). The oddity effect posits that any shoal member that stands out in appearance will be preferen ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |