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Narwhals
The narwhal (''Monodon monoceros'') is a species of toothed whale native to the Arctic. It is the only member of the genus ''Monodon'' and one of two living representatives of the family Monodontidae. The narwhal is a stocky cetacean with a relatively blunt snout, a large Melon (whale), melon, and a shallow ridge in place of a dorsal fin. Males of this species have a large () long tusk, which is a protruding left Canine tooth, canine thought to function as a weapon, a tool for feeding, in sexual selection, attracting mates or sensing water salinity. Specially adapted slow-twitch muscles, along with the jointed neck vertebrae and shallow dorsal ridge allow for easy movement through the Arctic environment, where the narwhal spends extended periods at great depths. The narwhal's geographic range overlaps with that of the similarly built and closely related beluga whale, and the animals are known to interbreed. Narwhals inhabit the Arctic waters of Canada, Greenland and Russia. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cetacean
Cetacea (; , ) is an infraorder of aquatic mammals belonging to the order Artiodactyla 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 movements of their tail, which ends in a paddle-like fluke, using their flipper-shaped forelimbs to steer. While the majority of cetaceans live in marine environments, a small number reside solely in brackish water, brackish or fresh water. Having a cosmopolitan distribution, they can be found in some rivers and all of Earth's oceans, and many species migrate throughout vast ranges with the changing of the seasons. Cetaceans are famous for cetacean intelligence, their high intelligence, complex social behaviour, and the enormous size of some of the group's members. For example, the blue whale reaches a maximum confirmed length of and a weight of 173 tonne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toothed Whale
The toothed whales (also called odontocetes, systematic name Odontoceti) are a parvorder of cetaceans that includes dolphins, porpoises, and all other whales with teeth, such as beaked whales and the sperm whales. 73 species of toothed whales are described. They are one of two living groups of cetaceans, the other being the baleen whales (Mysticeti), which have baleen instead of teeth. The two groups are thought to have diverged around 34 million years ago (mya). Toothed whales range in size from the and vaquita to the and sperm whale. Several species of odontocetes exhibit sexual dimorphism, in that there are size or other morphological differences between females and males. They have streamlined bodies and two limbs that are modified into flippers. Some can travel at up to 30 knots. Odontocetes have conical teeth designed for catching fish or squid. They have well-developed hearing that is well adapted for both air and water, so much so that some can survive even i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monodontidae
The cetacean family Monodontidae comprises two living whale species, the narwhal and the beluga whale and at least four extinct species, known from the fossil record. Beluga and narwhal are native to coastal regions and pack ice around the Arctic Ocean. Both species are relatively small whales, in length, with a forehead melon, and a short or absent snout. Premaxillary teeth are absent. They do not have a true dorsal fin, but do have a narrow ridge running along the back, which is much more pronounced in the narwhal. They are highly vocal animals, communicating with a wide range of sounds. Like other whales, they also use echolocation to navigate. Belugas can be found in the far north of the Atlantic and Pacific Oceans; the distribution of narwhals is restricted to the Arctic and Atlantic Oceans. Monodontids have a wide-ranging carnivorous diet, feeding on fish, molluscs, and small crustaceans. They have reduced teeth, with the beluga having numerous simple teeth, and the narwh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melon (whale)
The melon is a mass of adipose tissue found in the foreheads of all toothed whales. It focuses and modulates the animal's vocalizations and acts as a sound lens. It is thus a key organ involved in communication and Animal echolocation, echolocation. Description The melon is structurally part of the nasal apparatus and comprises most of the mass tissue between the blowhole (anatomy), blowhole and the tip of the snout. The function of the melon is not completely understood, but scientists believe it is a bioacoustic component, providing a means of focusing sounds used in echolocation and creating a similarity between characteristics of its tissue and the surrounding water so that acoustic energy can flow out of the head and into the environment with the least loss of energy. It was once hypothesized that the melon had functions in deep diving and buoyancy, but these ideas are no longer considered valid by cetologists. The varying composition of the melon creates a sound velocity ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tusk
Tusks are elongated, continuously growing front teeth that protrude well beyond the mouth of certain mammal species. They are most commonly canine tooth, canine teeth, as with Narwhal, narwhals, chevrotains, musk deer, water deer, muntjac, pigs, peccary, peccaries, hippopotamuses and walruses, or, in the case of elephants, elongated incisors. Tusks share common features such as extra-oral position, growth pattern, composition and structure, and lack of contribution to ingestion. Tusks are thought to have adapted to the extra-oral environments, like dry or aquatic or arctic. In most tusked species both the males and the females have tusks although the males' are larger. Most mammals with tusks have a pair of them growing out from either side of the mouth. Tusks are generally curved and have a smooth, continuous surface. The male narwhal's straight single Helix, helical tusk, which usually grows out from the left of the mouth, is an exception to the typical features of tusks describ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctogadus Glacialis
''Arctogadus glacialis'', known also with ambiguous common names Arctic cod and polar cod, is an Arctic species of fish in the cod family Gadidae, related to the true cod (genus ''Gadus''). ''Arctogadus glacialis'' is found in icy water. They grow to about 30 cm long, and are favorite food of narwhals and other arctic whales. Common names and taxonomy The common names "Arctic cod" and "polar cod" can refer to either ''Arctogadus glacialis'' or '' Boreogadus saida'', and "Arctic cod" may also refer to '' Eleginus nawaga''. Another Arctic gadid, the East Siberian cod (''Arctogadus borisovi''), was until recently considered the closest relative of ''A. glacialis''. It has, however, been found not to be distinct from ''A. glacialis'', and should be included in this species. According to this result, ''Arctogadus'' is a monotypic genus. However, ''Arctogadus'' is a close relative of '' Boreogadus'', and should perhaps be included in that genus. Appearance Arctic cod have been ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greenland Halibut
The Greenland halibut or Greenland turbot (''Reinhardtius hippoglossoides'') belongs to the family Pleuronectidae (the right-eye flounders), and is the monotypic, only species of the genus ''Reinhardtius''. It is a predatory fish that mostly ranges at depths between , and is found in the cold northern Atlantic Ocean, Atlantic, northern Pacific Ocean, Pacific, and Arctic Oceans. It has a variety of other English vernacular names, including black halibut, blue halibut, lesser halibut, and Newfoundland turbot; while both Newfoundland turbot and Greenland turbot are in common use in North America (sometimes even without the location, just "turbot"), these names are typically not used in Europe, where they can cause easy confusion with the true turbot (''Scophthalmus maximus''). The Greenland halibut is fished commercially across its range with disputes over the fishing rights for this species in the Atlantic Ocean off Canada resulting in the Turbot War of the mid-1990s (a "war" witho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cuttlefish
Cuttlefish, or cuttles, are Marine (ocean), marine Mollusca, molluscs of the order (biology), suborder Sepiina. They belong to the class (biology), class Cephalopoda which also includes squid, octopuses, and nautiluses. Cuttlefish have a unique internal mollusc shell, shell, the cuttlebone, which is used for control of buoyancy. Cuttlefish have large, W-shaped pupils, eight Cephalopod arm, arms, and two tentacles furnished with :wikt:denticulate, denticulated suckers, with which they secure their prey. They generally range in size from , with Cephalopod size, the largest species, the giant cuttlefish (''Sepia apama''), reaching in mantle (mollusc), mantle length and over in mass. Cuttlefish eat small molluscs, crabs, shrimp, fish, octopuses, worms, and other cuttlefish. Their predators include dolphins, larger fish (including sharks), seals, seabirds, and other cuttlefish. The typical life expectancy of a cuttlefish is about 1–2 years. Studies are said to indicate cuttlefis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shrimp
A shrimp (: shrimp (American English, US) or shrimps (British English, UK)) is a crustacean with an elongated body and a primarily Aquatic locomotion, swimming mode of locomotion – typically Decapods belonging to the Caridea or Dendrobranchiata, although some Shrimp#Non-decapods, crustaceans outside of this order are also referred to as "shrimp". Any small crustacean may also be referred to as "shrimp", regardless of resemblance. More narrow definitions may be restricted to Caridea, to smaller species of either of the aforementioned groups, or only the Marine life, marine species. Under a broader definition, ''shrimp'' may be synonymous with prawn, covering stalk-eyed swimming crustaceans with long, narrow muscular tails (Abdomen#Arthropoda, abdomens), long whiskers (Antenna (biology), antennae), and slender, Biramous, biramous legs. They swim forward by paddling the swimmerets on the underside of their abdomens, although their escape response is typically repeated flicks wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Armhook Squid
The Gonatidae, also known as armhook squid, are a family of moderately sized squid. The family contains about 19 species in three genera, widely distributed and plentiful in cold boreal waters of the Pacific Ocean. At least one species is known from Antarctic waters, and two from the North Atlantic. The genus '' Eogonatus'' was created for the species known as '' Eogonatus tinro'' because it did not have hooks on the tentacular club and it has 5 rows of teeth on the radula. Molecular studies in allozymes and mitochondrial DNA have indicated that this species nests within the genus '' Gonatus'', although other authorities treat it as a synonym of '' Gonatopsis okutanii''. Description Morphologically, armhook squid are fairly uniform: all species are characterised by the suckers of their arms, which are arranged in four rows (series) rather than the typical count of two. In most species, the arm's two mesial rows of suckers have been modified into hooks and the tentacular club ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human
Humans (''Homo sapiens'') or modern humans are the most common and widespread species of primate, and the last surviving species of the genus ''Homo''. They are Hominidae, great apes characterized by their Prehistory of nakedness and clothing#Evolution of hairlessness, hairlessness, bipedality, bipedalism, and high Human intelligence, intelligence. Humans have large Human brain, brains, enabling more advanced cognitive skills that facilitate successful adaptation to varied environments, development of sophisticated tools, and formation of complex social structures and civilizations. Humans are Sociality, highly social, with individual humans tending to belong to a Level of analysis, multi-layered network of distinct social groups — from families and peer groups to corporations and State (polity), political states. As such, social interactions between humans have established a wide variety of Value theory, values, norm (sociology), social norms, languages, and traditions (co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pack Ice
Pack or packs may refer to: Music * Packs (band), a Canadian indie rock band * ''Packs'' (album), by Your Old Droog * ''Packs'', a Berner album Places * Pack, Styria, defunct Austrian municipality * Pack, Missouri, United States (US) * Chefornak Airport, Alaska, US (by ICAO code) Groups of animals or people * Pack (canine), the family structure of African wild dogs, jackals and wolves ** Pack hunter, any animal that predates cooperatively * Cub scouts group, in scouting * Peloton, in road bicycle racing Containment, packaging, and shipping * Pack, a deck of playing cards * Backpack * Cigarette pack * Pack animal or beast of burden, an individual or type of working animal used by humans as means of transporting materials Other uses *Arctic ice pack * Pack (aircraft), P.A.C.K (Pneumatic Air Cycle Kit), a kit containing an air cycle machine that provides air conditioning as part of an aircraft's environmental control system * Pack (compression), a UNIX utility to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
