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Mercury In Fish
The presence of mercury in fish is a health concern for people who eat them, especially for women who are or may become pregnant, nursing mothers, and young children. Fish and shellfish concentrate mercury in their bodies, often in the form of methylmercury, a highly toxic organomercury compound. This element is known to bioaccumulate in humans, so bioaccumulation in seafood carries over into human populations, where it can result in mercury poisoning. Mercury is dangerous to both natural ecosystems and humans because it is a metal known to be highly toxic, especially due to its neurotoxic ability to damage the central nervous system. In human-controlled ecosystems of fish, usually done for market production of wanted seafood species, mercury clearly rises through the food chain via fish consuming small plankton, as well as through non-food sources such as underwater sediment. Fish products have been shown to contain varying amounts of heavy metals, particularly mercury and fat- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Longevity
The word " longevity" is sometimes used as a synonym for "life expectancy" in demography. However, the term ''longevity'' is sometimes meant to refer only to especially long-lived members of a population, whereas ''life expectancy'' is always defined statistically as the average number of years remaining at a given age. For example, a population's life expectancy at birth is the same as the average age at death for all people born in the same year (in the case of cohorts). Longevity is best thought of as a term for general audiences meaning 'typical length of life' and specific statistical definitions should be clarified when necessary. Reflections on longevity have usually gone beyond acknowledging the brevity of human life and have included thinking about methods to extend life. Longevity has been a topic not only for the scientific community but also for writers of travel, science fiction, and utopia A utopia ( ) typically describes an imaginary community or society that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whaling In Iceland
Whaling in Iceland began with spear-drift hunting as early as the 12th century, and continued in a vestigial form until the late 19th century, when other countries introduced modern commercial practices. Today, Iceland is one of a handful of countries that formally object to an ongoing moratorium established by the International Whaling Commission in 1986, and that still maintain a whaling fleet. One company remains concentrated on hunting fin whales, largely for export to Japan, while the only other one previously hunted minke whales for domestic consumption until 2020, as the meat was popular with tourists. In 2018, Icelandic whalers were accused of slaughtering a blue whale. Whaling was temporarily paused in Iceland between 2019 and 2021 as coronavirus restrictions, competition from subsidized Japanese whaling, and increasing domestic whale watching tourism have hampered the industry, however the practice is set to resume in 2022. A ban may come about by 2024 due to low de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whaling In Japan
Japanese whaling, in terms of active hunting of whales, is estimated by the Japan Whaling Association to have begun around the 12th century. However, Japanese whaling on an industrial scale began around the 1890s when Japan started to participate in the modern whaling industry, at that time an industry in which many countries participated. Japan resumed commercial whaling in July 2019, and since then whaling activities have been confined to its territorial waters and exclusive economic zone. During the 20th century, Japan was heavily involved in commercial whaling. This continued until the International Whaling Commission (IWC) moratorium on commercial whaling went into effect in 1986. Japan continued to hunt whales using the scientific research provision in the agreement and Japanese whaling was conducted by the Institute of Cetacean Research. This was allowed under IWC rules, although most IWC members opposed it. However, in March 2014, the UN's International Court of Justice ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whale Meat
Whale meat, broadly speaking, may include all cetaceans (whales, dolphins, porpoises) and all parts of the animal: muscle (meat), organs (offal), skin (muktuk), and fat (blubber). There is relatively little demand for whale meat, compared to farmed livestock. Commercial whaling, which has faced opposition for decades, continues today in very few countries (mainly Iceland, Japan and Norway), despite whale meat being eaten across Western Europe and colonial America previously. However, in areas where dolphin drive hunting and aboriginal whaling exist, marine mammals are eaten locally as part of a subsistence economy: the Faroe Islands, the circumpolar Arctic (the Inuit in Canada and Greenland, related peoples in Alaska, the Chukchi people of Siberia), other indigenous peoples of the United States (including the Makah people of the Pacific Northwest), St. Vincent and the Grenadines (mainly on the island of Bequia), some of villages in Indonesia and in certain South Pacific islan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dolphin
A dolphin is an aquatic mammal within the infraorder Cetacea. Dolphin species belong to the families Delphinidae (the oceanic dolphins), Platanistidae (the Indian river dolphins), Iniidae (the New World river dolphins), Pontoporiidae (the brackish dolphins), and the extinct Lipotidae (baiji or Chinese river dolphin). There are 40 extant species named as dolphins. Dolphins range in size from the and Maui's dolphin to the and orca. Various species of dolphins exhibit sexual dimorphism where the males are larger than females. They have streamlined bodies and two limbs that are modified into flippers. Though not quite as flexible as seals, some dolphins can briefly travel at speeds of per hour or leap about . Dolphins use their conical teeth to capture fast-moving prey. They have well-developed hearing which is adapted for both air and water. It is so well developed that some can survive even if they are blind. Some species are well adapted for diving to great depths. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whale
Whales are a widely distributed and diverse group of fully aquatic placental marine mammals. As an informal and colloquial grouping, they correspond to large members of the infraorder Cetacea, i.e. all cetaceans apart from dolphins and porpoises. Dolphins and porpoises may be considered whales from a formal, cladistic perspective. Whales, dolphins and porpoises belong to the order Cetartiodactyla, which consists of even-toed ungulates. Their closest non-cetacean living relatives are the hippopotamuses, from which they and other cetaceans diverged about 54 million years ago. The two parvorders of whales, baleen whales (Mysticeti) and toothed whales (Odontoceti), are thought to have had their last common ancestor around 34 million years ago. Mysticetes include four extant (living) families: Balaenopteridae (the rorquals), Balaenidae (right whales), Cetotheriidae (the pygmy right whale), and Eschrichtiidae (the grey whale). Odontocetes include the Monodontidae (beluga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cetacea
Cetacea (; , ) is an infraorder of aquatic mammals that includes whales, dolphins, and porpoises. Key characteristics are their fully aquatic lifestyle, streamlined body shape, often large size and exclusively carnivorous diet. They propel themselves through the water with powerful up-and-down movement of their tail which ends in a paddle-like fluke, using their flipper-shaped forelimbs to maneuver. While the majority of cetaceans live in marine environments, a small number exclusively reside in brackish water or fresh water. Having a cosmopolitan distribution, they can be found in some rivers and all of Earth's oceans, and many species inhabit vast ranges where they migrate with the changing of the seasons. Cetaceans are famous for their high intelligence and complex social behaviour as well as for the enormous size of some of the group's members, such as the blue whale which reaches a maximum confirmed length of 29.9 meters (98 feet) and a weight of 173 tonnes (190 short to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tilefish
250px, Blue blanquillo, ''Malacanthus latovittatus'' Tilefishes are mostly small perciform marine fish comprising the family Malacanthidae. They are usually found in sandy areas, especially near coral reefs. Commercial fisheries exist for the largest species, making them important food fish. However, the U.S. Food and Drug Administration warns pregnant or breastfeeding women against eating tilefish and some other fish due to mercury contamination. Exceptionally colorful smaller species of tilefish are favored for aquariums. Taxonomic issues The family is further divided into two subfamilies: Latilinae, sometimes called the Branchiosteginae, and Malacanthinae. Some authors regard these subfamilies as two evolutionarily distinct families. The placement of this family within the Eupercaria is still not certain. The 5th Edition of Fishes of the World classifies them within the Perciformes but in a grouping of seven families which may have a relationship to Acanthuroidei, Mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
King Mackerel
The king mackerel (''Scomberomorus cavalla'') or kingfish, is a migratory species of mackerel of the western Atlantic Ocean and Gulf of Mexico. It is an important species to both the commercial and recreational fishing industries. Description The king mackerel is a medium-sized fish, typically encountered from to , but is known to exceed . The entire body is covered with very small, hardly visible, loosely attached scales. The first (spiny) dorsal fin is entirely colorless and is normally folded back into a body groove, as are the pelvic fins. The lateral line starts high on the shoulder, dips abruptly at mid-body and then continues as a wavy horizontal line to the tail. Coloration is olive on the back, fading to silver with a rosy iridescence on the sides, fading to white on the belly. Fish under show yellowish-brown spots on the flanks, somewhat smaller than the spots of the Atlantic Spanish mackerel, ''Scomberomorus maculatus''. Its cutting-edged teeth are large, uniform ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swordfish
Swordfish (''Xiphias gladius''), also known as broadbills in some countries, are large, highly migratory predatory fish characterized by a long, flat, pointed bill. They are a popular sport fish of the billfish category, though elusive. Swordfish are elongated, round-bodied, and lose all teeth and scales by adulthood. These fish are found widely in tropical and temperate parts of the Atlantic, Pacific, and Indian Oceans, and can typically be found from near the surface to a depth of , and exceptionally up to depths of 2,234 m. They commonly reach in length, and the maximum reported is in length and in weight.Gardieff, S. Swordfish.' Florida Museum of Natural History. Accessed 26 December 2011 They are the sole member of their family, Xiphiidae. Taxonomy and etymology The swordfish is named after its long pointed, flat bill, which resembles a sword. The species name, ''Xiphias gladius'', derives from Greek (''xiphias'', "swordfish"), itself from (''xiphos'', "sword") and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shark
Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachimorpha (or Selachii) and are the sister group to the rays. However, the term "shark" has also been used to refer to all extinct members of Chondrichthyes with a shark-like morphology, such as hybodonts and xenacanths. The oldest modern sharks are known from the Early Jurassic. They range in size from the small dwarf lanternshark (''Etmopterus perryi''), a deep sea species that is only in length, to the whale shark (''Rhincodon typus''), the largest fish in the world, which reaches approximately in length. Sharks are found in all seas and are common to depths up to . They generally do not live in freshwater, although there are a few known exceptions, such as the bull shark and the river shark, which can be found in both seawater and fresh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
