84-473: К-3 was a project 627 "Кит" ( kit , meaning " whale "; NATO reporting name " November ") submarine of the Soviet Navy 's Northern Fleet , the first nuclear submarine of the Soviet Union . The vessel was prototyped in wood, with each of five segments scattered between five different locations about Leningrad , including the Astoria Hotel . She was built in Molotovsk , launched on 9 August 1957, commissioned in July 1958, and homeported at Zapadnaya Litsa on
168-547: A cigarette lighter in the torpedo compartment and found the position of a sailor's body suspicious. They ruled that the sailor's smoking had caused the fire and prohibited any award. In 1991 a memorial was erected in Zapadnaya Litsa to the men lost aboard К-3. In 2007 the Russian Awards Committee (Российский наградной комитет) issued the medal "For 50 Years Of The Submarine "Leninskiy Komsomol"". The submarine
252-408: A tapetum lucidum ; these adaptations allow for large amounts of light to pass through the eye and, therefore, a very clear image of the surrounding area. They also have glands on the eyelids and outer corneal layer that act as protection for the cornea. The olfactory lobes are absent in toothed whales, suggesting that they have no sense of smell. Some whales, such as the bowhead whale , possess
336-485: A vomeronasal organ , which does mean that they can "sniff out" krill. Whales are not thought to have a good sense of taste, as their taste buds are atrophied or missing altogether. However, some toothed whales have preferences between different kinds of fish, indicating some sort of attachment to taste. The presence of the Jacobson's organ indicates that whales can smell food once inside their mouth, which might be similar to
420-733: A different reason for it, for example, the killer whale was named "Ballena asesina" 'killer whale' by Spanish sailors. The term "Great Whales" covers those currently regulated by the International Whaling Commission : the Odontoceti family Physeteridae (sperm whales); and the Mysticeti families Balaenidae (right and bowhead whales), Eschrichtiidae (grey whales), and some of the Balaenopteridae (Minke, Bryde's, Sei, Blue and Fin; not Eden's and Omura's whales). The whales are part of
504-570: A form of tourism around the world. The word "whale" comes from the Old English hwæl , from Proto-Germanic *hwalaz , from Proto-Indo-European *(s)kwal-o- , meaning "large sea fish". The Proto-Germanic *hwalaz is also the source of Old Saxon hwal , Old Norse hvalr , hvalfiskr , Swedish val , Middle Dutch wal , walvisc , Dutch walvis , Old High German wal , and German Wal . Other archaic English forms include wal, wale, whal, whalle, whaille, wheal , etc. The term "whale"
588-420: A small bulge sitting on top of its skull, whereas a sperm whale's head is filled up mainly with the melon. The whale eye is relatively small for its size, yet they do retain a good degree of eyesight. As well as this, the eyes of a whale are placed on the sides of its head, so their vision consists of two fields, rather than a binocular view like humans have. When belugas surface, their lens and cornea correct
672-415: A source of food (i.e. seafood ) and as raw material for fodders (e.g. feeder fish and fish meal ), pharmaceuticals (e.g. fish oil , krill oil , cytarabine and bryostatin ) and various industrial chemicals (e.g. chitin and bioplastics , formerly also whale oil ). The harvesting of aquatic animals, especially finfish , shellfish and inkfish , provides direct and indirect employment to
756-456: A strong desire on behalf of the whales to communicate with humans, as whales have a very different vocal mechanism, so imitating human speech likely takes considerable effort. Whales emit two distinct kinds of acoustic signals, which are called whistles and clicks: Clicks are quick broadband burst pulses, used for sonar , although some lower-frequency broadband vocalizations may serve a non-echolocative purpose such as communication; for example,
840-429: A two- to three-chambered stomach that is similar in structure to those of terrestrial carnivores. Mysticetes contain a proventriculus as an extension of the oesophagus ; this contains stones that grind up food. They also have fundic and pyloric chambers. Whales have two flippers on the front, and a tail fin. These flippers contain four digits. Although whales do not possess fully developed hind limbs, some, such as
924-509: Is a popular pastime in both developed and developing countries , and the manufacturing , retail and service sectors associated with recreational fishing have together conglomerated into a multibillion-dollar industry. In 2014 alone, around 11 million saltwater sportfishing participants the United States generated USD$ 58 billion of retail revenue (comparatively, commercial fishing generated USD$ 141 billion that same year). In 2021,
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#17330850653381008-712: Is also applied to riparian mammals like the river otter ( Lontra canadensis ) and beavers (family Castoridae ), although they are technically semiaquatic or amphibious. Unlike the more common gill -bearing aquatic animals, these air-breathing animals have lungs (which are homologous to the swim bladders in bony fish ) and need to surface periodically to change breaths, but their ranges are not restricted by oxygen saturation in water, although salinity changes can still affect their physiology to an extent. There are also reptilian animals that are highly evolved for life in water, although most extant aquatic reptiles, including crocodilians , turtles , water snakes and
1092-631: Is any animal , whether vertebrate or invertebrate , that lives in a body of water for all or most of its lifetime. Aquatic animals generally conduct gas exchange in water by extracting dissolved oxygen via specialised respiratory organs called gills , through the skin or across enteral mucosae , although some are evolved from terrestrial ancestors that re- adapted to aquatic environments (e.g. marine reptiles and marine mammals ), in which case they actually use lungs to breathe air and are essentially holding their breath when living in water. Some species of gastropod mollusc , such as
1176-515: Is characterized by the presence of baleen, a sieve-like structure in the upper jaw made of keratin , which it uses to filter plankton , among others, from the water. Odontocetes (toothed whales) are characterized by bearing sharp teeth for hunting, as opposed to their counterparts' baleen. Cetaceans and artiodactyls now are classified under the order Cetartiodactyla , often still referred to as Artiodactyla, which includes both whales and hippopotamuses . The hippopotamus and pygmy hippopotamus are
1260-437: Is helpful for a 100-ton whale), protection to some extent as predators would have a hard time getting through a thick layer of fat, and energy for fasting when migrating to the equator; the primary usage for blubber is insulation from the harsh climate. It can constitute as much as 50% of a whale's body weight. Calves are born with only a thin layer of blubber, but some species compensate for this with thick lanugos. Whales have
1344-406: Is home to elongated spindle neurons that, prior to 2007, were known only in hominids. In humans, these cells are involved in social conduct, emotions, judgement, and theory of mind. Whale spindle neurons are found in areas of the brain that are homologous to where they are found in humans, suggesting that they perform a similar function. Brain size was previously considered a major indicator of
1428-442: Is in their feeding adaptations and subsequent behaviour. Balaenopterids are the rorquals. These animals, along with the cetotheriids, rely on their throat pleats to gulp large amounts of water while feeding. The throat pleats extend from the mouth to the navel and allow the mouth to expand to a large volume for more efficient capture of the small animals they feed on. Balaenopterids consist of two genera and eight species. Balaenids are
1512-438: Is sometimes used interchangeably with dolphins and porpoises , acting as a synonym for Cetacea . Six species of dolphins have the word "whale" in their name, collectively known as blackfish: the orca , or killer whale, the melon-headed whale , the pygmy killer whale , the false killer whale , and the two species of pilot whales , all of which are classified under the family Delphinidae (oceanic dolphins). Each species has
1596-756: Is still recorded in some countries, particularly in Africa and Asia . Overfishing and destructive fishing practices fuelled by commercial incentives have reduced fish stocks beyond sustainable levels in many world regions, causing the fishery industry to maladaptively fishing down the food web . It was estimated in 2014 that global fisheries were adding US$ 270 billion a year to global GDP , but by full implementation of sustainable fishing , that figure could rise by as much as US$ 50 billion. UN Food and Agriculture Organization projects world production of aquatic animals to reach 205 million tonnes by 2032. Where sex-disaggregated data are available, approximately 24 percent of
1680-442: Is taken in and expelled. They are warm-blooded , and have a layer of fat, or blubber , under the skin. With streamlined fusiform bodies and two limbs that are modified into flippers, whales can travel at speeds of up to 20 knots , though they are not as flexible or agile as seals . Whales produce a great variety of vocalizations, notably the extended songs of the humpback whale . Although whales are widespread, most species prefer
1764-401: Is then expelled through the baleen, leaving their prey trapped inside. This is an efficient method of hunting, in which the whale has no major competitors. Odontocetes are known as toothed whales; they have teeth and only one blowhole. They rely on their well-developed sonar to find their way in the water. Toothed whales send out ultrasonic clicks using the melon . Sound waves travel through
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#17330850653381848-562: The Indohyus , an extinct chevrotain -like ungulate, from which they split approximately 48 million years ago. Primitive cetaceans, or archaeocetes , first took to the sea approximately 49 million years ago and became fully aquatic 5–10 million years later. What defines an archaeocete is the presence of anatomical features exclusive to cetaceans, alongside other primitive features not found in modern cetaceans, such as visible legs or asymmetrical teeth. Their features became adapted for living in
1932-479: The Cenozoic ) remain fully aquatic in saltwater ecosystems . Amphibians , while still requiring access to water to inhabit, are separated into their own ecological classification. The majority of amphibians — except the order Gymnophiona ( caecilians ), which are mainly terrestrial burrowers — have a fully aquatic larval form known as tadpoles , but those from the order Anura ( frogs and toads ) and some of
2016-558: The Kola Peninsula . K-3 was designed by Vladimir Peregoudov . Her initial captain was Leonid Osipenko, and the executive officer was Lev Zhiltsov , who had the important task of assembling the first crew. On 17 June 1962, by this time under the command of Zhiltsov, К-3 reached the North Pole underwater, the first among Soviet submarines (a feat performed nearly four years earlier by USS Nautilus ). The submarine also surfaced on
2100-468: The Monodontidae (belugas and narwhals), Physeteridae (the sperm whale ), Kogiidae (the dwarf and pygmy sperm whale), and Ziphiidae (the beaked whales), as well as the six families of dolphins and porpoises which are not considered whales in the informal sense. Whales are fully aquatic, open-ocean animals: they can feed, mate, give birth, suckle and raise their young at sea. Whales range in size from
2184-597: The algae octopus (whose larvae are completely planktonic , but adults are highly terrestrial). Aquatic animals are a diverse polyphyletic group based purely on the natural environments they inhabit, and many morphological and behavioral similarities among them are the result of convergent evolution . They are distinct from terrestrial and semi-aquatic animals, who can survive away from water bodies, while aquatic animals often die of dehydration or hypoxia after prolonged removal out of water due to either gill failure or compressive asphyxia by their own body weight (as in
2268-541: The beluga and the narwhal . They both reside in the frigid arctic and both have large amounts of blubber. Belugas, being white, hunt in large pods near the surface and around pack ice, their coloration acting as camouflage. Narwhals, being black, hunt in large pods in the aphotic zone, but their underbelly still remains white to remain camouflaged when something is looking directly up or down at them. They have no dorsal fin to prevent collision with pack ice. Physeterids and Kogiids consist of sperm whales . Sperm whales consist
2352-433: The blowhole , forming an upward, steamy spout, followed by inhaling fresh air into the lungs; a humpback whale's lungs can hold about 5,000 litres (1,300 US gal) of air. Spout shapes differ among species, which facilitates identification. All whales have a thick layer of blubber . In species that live near the poles, the blubber can be as thick as 11 inches (28 cm). This blubber can help with buoyancy (which
2436-717: The eastern emerald sea slug , are even capable of kleptoplastic photosynthesis via endosymbiosis with ingested yellow-green algae . Almost all aquatic animals reproduce in water, either oviparously or viviparously , and many species routinely migrate between different water bodies during their life cycle . Some animals have fully aquatic life stages (typically as eggs and larvae ), while as adults they become terrestrial or semi-aquatic after undergoing metamorphosis . Such examples include amphibians such as frogs , many flying insects such as mosquitoes , mayflies , dragonflies , damselflies and caddisflies , as well as some species of cephalopod molluscs such as
2520-541: The hormone prolactin , while in salmon ( Salmo salar ) the hormone cortisol plays a key role during this process. Freshwater molluscs include freshwater snails and freshwater bivalves . Freshwater crustaceans include freshwater shrimps , crabs , crayfish , freshwater pirahnas and copepods . In addition to water-breathing animals (e.g. fish , most molluscs , etc.), the term "aquatic animal" can be applied to air-breathing tetrapods who have evolved for aquatic life. The most proliferative extant group are
2604-449: The kidney . Although most aquatic organisms have a limited ability to regulate their osmotic balance and therefore can only live within a narrow range of salinity, diadromous fish have the ability to migrate between fresh and saline water bodies. During these migrations they undergo changes to adapt to the surroundings of the changed salinities; these processes are hormonally controlled. The European eel ( Anguilla anguilla ) uses
Soviet submarine K-3 Leninsky Komsomol - Misplaced Pages Continue
2688-479: The labyrinth organ and even primitive lungs (lungfish and bichirs). Most molluscs have gills , while some freshwater gastropods (e.g. Planorbidae ) have evolved pallial lungs and some amphibious species (e.g. Ampullariidae ) have both. Many species of octopus have cutaneous respiration that allows them to survive out of water at the intertidal zones , with at least one species ( Abdopus aculeatus ) being routinely terrestrial hunting crabs among
2772-411: The livelihood of over 500 million people in developing countries , and both the fishing industry and aquaculture make up a major component of the primary sector of the economy . The UN Food and Agriculture Organization estimates that global consumption of aquatic animals in 2022 was 185 million tonnes (live weight equivalent), an increase of 4 percent from 2020. The value of the 2022 global trade
2856-405: The marine environment . Major anatomical changes included their hearing set-up that channeled vibrations from the jaw to the earbone ( Ambulocetus 49 mya ), a streamlined body and the growth of flukes on the tail ( Protocetus 43 mya), the migration of the nostrils toward the top of the cranium ( blowholes ), and the modification of the forelimbs into flippers ( Basilosaurus 35 mya), and
2940-635: The marine iguana , are technically semi-aquatic rather than fully aquatic, and most of them only inhabit freshwater ecosystems . Marine reptiles were once a dominant group of ocean predators that altered the marine fauna during the Mesozoic , although most of them died out during the Cretaceous-Paleogene extinction event and now only the sea turtles (the only remaining descendants of the Mesozoic marine reptiles) and sea snakes (which only evolved during
3024-422: The marine mammals , such as those in the orders Cetacea ( whales , dolphins and porpoises , with some freshwater species ) and Sirenia ( dugongs and manatees ), who are too evolved for aquatic life to survive on land at all (where they will die of beaching ), as well as the highly aquatically adapted but land-dwelling pinnipeds ( true seals , eared seals and the walrus ). The term " aquatic mammal "
3108-417: The photic zone . Ziphiids consist of 22 species of beaked whale . These vary from size, to coloration, to distribution, but they all share a similar hunting style. They use a suction technique, aided by a pair of grooves on the underside of their head, not unlike the throat pleats on the rorquals , to feed. As a formal clade (a group which does not exclude any descendant taxon ), odontocetes also contains
3192-424: The porpoises (Phocoenidae) and four or five living families of dolphins: oceanic dolphins ( Delphinidae ), South Asian river dolphins ( Platanistidae ), the possibly extinct Yangtze River dolphin ( Lipotidae ), South American river dolphins ( Iniidae ), and La Plata dolphin (Pontoporiidae). Whales are descendants of land-dwelling mammals of the artiodactyl order (even-toed ungulates). They are related to
3276-725: The tidal pools of rocky shores . Aquatic animals play an important role for the environment as indicator species , as they are particularly sensitive to deterioration in water quality and climate change . Biodiversity of aquatic animals is also an important factor for the sustainability of aquatic ecosystems as it reflects the food web status and the carrying capacity of the local habitats . Many migratory aquatic animals, predominantly forage fish (such as sardines ) and euryhaline fish (such as salmon ), are keystone species that accumulate and transfer biomass between marine , freshwater and even to terrestrial ecosystems . Aquatic animals are important to humans as
3360-522: The water column . Aquatic animals (especially freshwater animals) are often of special concern to conservationists because of the fragility of their environments. Aquatic animals are subject to pressure from overfishing / hunting , destructive fishing , water pollution , acidification , climate change and competition from invasive species . Many aquatic ecosystems are at risk of habitat destruction / fragmentation , which puts aquatic animals at risk as well. Aquatic animals play an important role in
3444-484: The 2.6 metres (8.5 ft) and 135 kilograms (298 lb) dwarf sperm whale to the 29.9 metres (98 ft) and 190 tonnes (210 short tons) blue whale , which is the largest known animal that has ever lived. The sperm whale is the largest toothed predator on Earth. Several whale species exhibit sexual dimorphism , in that the females are larger than males. Baleen whales have no teeth; instead, they have plates of baleen, fringe-like structures that enable them to expel
Soviet submarine K-3 Leninsky Komsomol - Misplaced Pages Continue
3528-420: The 2.6-metre (8.5 ft) and 135-kilogram (298 lb) dwarf sperm whale to the 34-metre (112 ft) and 190-metric-ton (210-short-ton) blue whale. Overall, they tend to dwarf other cetartiodactyls; the blue whale is the largest creature on Earth. Several species have female-biased sexual dimorphism, with the females being larger than the males. One exception is with the sperm whale, which has males larger than
3612-550: The Inuit and the coastal peoples of Vietnam and Ghana, who sometimes hold whale funerals. Whales occasionally feature in literature and film. A famous example is the great white whale in Herman Melville 's novel Moby-Dick . Small whales, such as belugas , are sometimes kept in captivity and trained to perform tricks, but breeding success has been poor and the animals often die within a few months of capture. Whale watching has become
3696-508: The Pole (a feat performed three years before by USS Skate ). For this voyage, she was awarded the name Leninsky Komsomol ( Ленинский Комсомол ) on 9 October 1962, and her crew, rather than training in military operations, began taking part in many congresses and conferences. This idle life continued until Summer 1967 when a boat that had been scheduled for patrol in the Mediterranean Sea
3780-447: The baleen whales (Mysticetes) and the toothed whales (Odontocetes). Whales have torpedo-shaped bodies with non-flexible necks, limbs modified into flippers, non-existent external ear flaps, a large tail fin, and flat heads (with the exception of monodontids and ziphiids ). Whale skulls have small eye orbits, long snouts (with the exception of monodontids and ziphiids) and eyes placed on the sides of its head. Whales range in size from
3864-552: The case of whale beaching ). Along with aquatic plants , algae and microbes , aquatic animals form the food webs of various marine , brackish and freshwater aquatic ecosystems . The term aquatic can be applied to animals that live in either fresh water or salt water . However, the adjective marine is most commonly used for animals that live in saltwater or sometimes brackish water , i.e. in oceans , shallow seas , estuaries , etc. Aquatic animals can be separated into four main groups according to their positions within
3948-529: The closest living relatives of cetaceans are the hippopotamuses ; these share a semi-aquatic ancestor that branched off from other artiodactyls some 60 mya. Around 40 mya, a common ancestor between the two branched off into cetacea and anthracotheres ; nearly all anthracotheres became extinct at the end of the Pleistocene 2.5 mya, eventually leaving only one surviving lineage – the hippopotamus. Whales split into two separate parvorders around 34 mya –
4032-690: The colder waters of the Northern and Southern Hemispheres and migrate to the equator to give birth. Species such as humpbacks and blue whales are capable of travelling thousands of miles without feeding. Males typically mate with multiple females every year, but females only mate every two to three years. Calves are typically born in the spring and summer; females bear all the responsibility for raising them. Mothers in some species fast and nurse their young for one to two years. Once relentlessly hunted for their products, whales are now protected by international law. The North Atlantic right whales nearly became extinct in
4116-404: The concentration of myoglobin than haemoglobin. Before going on long dives, many whales exhibit a behaviour known as sounding; they stay close to the surface for a series of short, shallow dives while building their oxygen reserves, and then make a sounding dive. The whale ear has specific adaptations to the marine environment. In humans, the middle ear works as an impedance equalizer between
4200-553: The females. Odontocetes, such as the sperm whale, possess teeth with cementum cells overlying dentine cells. Unlike human teeth, which are composed mostly of enamel on the portion of the tooth outside of the gum, whale teeth have cementum outside the gum. Only in larger whales, where the cementum is worn away on the tip of the tooth, does enamel show. Mysticetes have large whalebone , as opposed to teeth, made of keratin. Mysticetes have two blowholes, whereas Odontocetes contain only one. Breathing involves expelling stale air from
4284-524: The huge mouthfuls of water they take in while retaining the krill and plankton they feed on. Because their heads are enormous—making up as much as 40% of their total body mass—and they have throat pleats that enable them to expand their mouths, they are able to take huge quantities of water into their mouth at a time. Baleen whales also have a well-developed sense of smell. Toothed whales, in contrast, have conical teeth adapted to catching fish or squid . They also have such keen hearing—whether above or below
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#17330850653384368-819: 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
4452-567: The intelligence of an animal. Since most of the brain is used for maintaining bodily functions, greater ratios of brain-to-body mass may increase the amount of brain mass available for more complex cognitive tasks. Allometric analysis indicates that mammalian brain size scales at approximately the ⅔ or ¾ exponent of the body mass. Comparison of a particular animal's brain size with the expected brain size based on such allometric analysis provides an encephalisation quotient that can be used as another indication of animal intelligence. Sperm whales have
4536-946: The largely terrestrial mammalian clade Laurasiatheria . Whales do not form a clade or order ; the infraorder Cetacea includes dolphins and porpoises , which are not considered whales in the informal sense. The phylogenetic tree shows the relationships of whales and other mammals, with whale groups marked in green. ( carnivorans and allies) [REDACTED] ( horses , rhinos , tapirs ) [REDACTED] ( camels, llamas ) [REDACTED] ( pigs, hogs, peccaries ) [REDACTED] ( cattle , sheep , antelopes ) [REDACTED] ( hippos ) [REDACTED] ( † Ambulocetus , † Protocetus , † Basilosaurus ) ( right whales , grey whales , rorquals ) ( dolphins , porpoises , beluga whales , narwhals ) ( river dolphins ) ( sperm whales ) ( beaked whales ) Cetaceans are divided into two parvorders. The larger parvorder, Mysticeti (baleen whales),
4620-399: The largest and smallest odontocetes, and spend a large portion of their life hunting squid. P. macrocephalus spends most of its life in search of squid in the depths; these animals do not require any degree of light at all, in fact, blind sperm whales have been caught in perfect health. The behaviour of Kogiids remains largely unknown, but, due to their small lungs, they are thought to hunt in
4704-409: The largest brain mass of any animal on Earth, averaging 8,000 cubic centimetres (490 in ) and 7.8 kilograms (17 lb) in mature males, in comparison to the average human brain which averages 1,450 cubic centimetres (88 in ) in mature males. The brain-to-body mass ratio in some odontocetes, such as belugas and narwhals, is second only to humans. Aquatic animal An aquatic animal
4788-524: The major producer (36% of the total), followed by India (8%), Indonesia (7%), Vietnam (5%) and Peru (3%). Total fish production in 2016 reached an all-time high of 171 million tonnes, of which 88% was utilized for direct human consumption, resulting in a record-high per capita consumption of 20.3 kg (45 lb). Since 1961 the annual global growth in fish consumption has been twice as high as population growth. While annual growth of aquaculture has declined in recent years, significant double-digit growth
4872-517: The nearsightedness that results from the refraction of light; they contain both rod and cone cells, meaning they can see in both dim and bright light, but they have far more rod cells than they do cone cells. Whales do, however, lack short wavelength sensitive visual pigments in their cone cells indicating a more limited capacity for colour vision than most mammals. Most whales have slightly flattened eyeballs, enlarged pupils (which shrink as they surface to prevent damage), slightly flattened corneas and
4956-440: The neck vertebrae, while increasing stability when swimming at high speeds, decreases flexibility; whales are unable to turn their heads. When swimming, whales rely on their tail fin to propel them through the water. Flipper movement is continuous. Whales swim by moving their tail fin and lower body up and down, propelling themselves through vertical movement, while their flippers are mainly used for steering. Some species log out of
5040-696: The order Urodela ( salamanders ) will metamorphosize into lung -bearing and sometimes skin-breathing terrestrial adults, and most of them may return to the water to breed . Axolotl , a Mexican salamander that retains its larval external gills into adulthood, is the only extant amphibian that remains fully aquatic throughout the entire life cycle . Certain amphibious fish also evolved to breathe air to survive oxygen-deprived waters , such as lungfishes , mudskippers , labyrinth fishes , bichirs , arapaima and walking catfish . Their abilities to breathe atmospheric oxygen are achieved via skin-breathing, enteral respiration , or specialized gill organs such as
5124-417: The outside air's low impedance and the cochlear fluid's high impedance. In whales, and other marine mammals, there is no great difference between the outer and inner environments. Instead of sound passing through the outer ear to the middle ear, whales receive sound through the throat, from which it passes through a low-impedance fat-filled cavity to the inner ear. The whale ear is acoustically isolated from
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#17330850653385208-440: The pulsed calls of belugas. Pulses in a click train are emitted at intervals of ≈35–50 milliseconds , and in general these inter-click intervals are slightly greater than the round-trip time of sound to the target. Whistles are narrow-band frequency modulated (FM) signals, used for communicative purposes, such as contact calls. Whales are known to teach, learn, cooperate, scheme, and grieve. The neocortex of many species of whale
5292-464: The right whales. These animals have very large heads, which can make up as much as 40% of their body mass, and much of the head is the mouth. This allows them to take in large amounts of water into their mouths, letting them feed more effectively. Eschrichtiids have one living member: the grey whale. They are bottom feeders, mainly eating crustaceans and benthic invertebrates. They feed by turning on their sides and taking in water mixed with sediment, which
5376-549: The sensation of taste. Whale vocalization is likely to serve several purposes. Some species, such as the humpback whale, communicate using melodic sounds, known as whale song . These sounds may be extremely loud, depending on the species. Humpback whales only have been heard making clicks, while toothed whales use sonar that may generate up to 20,000 watts of sound (+73 dBm or +43 dBw ) and be heard for many miles. Captive whales have occasionally been known to mimic human speech. Scientists have suggested this indicates
5460-515: The shrinking and eventual disappearance of the hind limbs (the first odontocetes and mysticetes 34 mya). Whale morphology shows several examples of convergent evolution , the most obvious being the streamlined fish-like body shape. Other examples include the use of echolocation for hunting in low light conditions — which is the same hearing adaptation used by bats — and, in the rorqual whales, jaw adaptations, similar to those found in pelicans , that enable engulfment feeding. Today,
5544-400: The skull by air-filled sinus pockets, which allow for greater directional hearing underwater. Odontocetes send out high-frequency clicks from an organ known as a melon . This melon consists of fat, and the skull of any such creature containing a melon will have a large depression. The melon size varies between species, the bigger the more dependent they are on it. A beaked whale for example has
5628-429: The sperm whale and bowhead whale, possess discrete rudimentary appendages, which may contain feet and digits. Whales are fast swimmers in comparison to seals, which typically cruise at 5–15 kn, or 9–28 kilometres per hour (5.6–17.4 mph); the fin whale, in comparison, can travel at speeds up to 47 kilometres per hour (29 mph) and the sperm whale can reach speeds of 35 kilometres per hour (22 mph). The fusing of
5712-494: The submarine surfaced. Four days later, Leninsky Komsomol returned to base. 39 crew members died in the fire. The subsequent investigation determined that the most probable cause of the fire was ignition of an explosive concentration of hydraulic oil, and that the reactions of the crew were prompt and correct. Numerous awards were recommended for the crew, including seven nominations for Hero of Soviet Union —four of them posthumous . A later commission from Moscow , however, found
5796-429: The submarine. The automatic extinguishers were based on carbon dioxide gas, which killed the crew members who were in the first and second compartments in the submarine. When the dividing door in the bulkhead from the third compartment was opened to see what had happened to the people in the second compartment, the gas spread, and more people lost consciousness. The forward compartments were then completely sealed off, and
5880-544: The supply chain. These practices are based on temperature reduction ( chilling and freezing ), heat treatment ( canning , boiling and smoking ), reduction of available water ( drying , salting and smoking) and changing of the storage environment ( vacuum packaging , modified atmosphere packaging and refrigeration). Aquatic animal products also require special facilities such as cold storage and refrigerated transport, and rapid delivery to consumers. In addition to commercial and subsistence fishing , recreational fishing
5964-526: The surface of the water—that some can survive even if they are blind. Some species, such as sperm whales, are particularly well adapted for diving to great depths to catch squid and other favoured prey. Whales evolved from land-living mammals, and must regularly surface to breathe air, although they can remain underwater for long periods of time. Some species, such as the sperm whale , can stay underwater for up to 90 minutes. They have blowholes (modified nostrils) located on top of their heads, through which air
6048-521: The total revenue of recreational fishing industry in the United States overtook those of Lockheed Martin , Intel , Chrysler and Google ; and together with personnel salary (about USD$ 39.5 billion) and various tolls and fees collected by fisheries management agencies (about USD$ 17 billion), contributed almost USD$ 129 billion to the GDP of the United States , roughly 1% of the national GDP and more than
6132-434: The total workforce were women; of these, 53 percent were employed in the sector on a full-time basis, a great improvement since 1995, when only 32 percent of women were employed full time. Aquatic animal are highly perishable and several chemical and biological changes take place immediately after death; this can result in spoilage and food safety risks if good handling and preservation practices are not applied all along
6216-563: The twentieth century, with a population low of 450, and the North Pacific grey whale population is ranked Critically Endangered by the IUCN . Besides the threat from whalers, they also face threats from bycatch and marine pollution. The meat, blubber and baleen of whales have traditionally been used by indigenous peoples of the Arctic. Whales have been depicted in various cultures worldwide, notably by
6300-461: The water, which may allow them to travel faster. Their skeletal anatomy allows them to be fast swimmers. Most species have a dorsal fin . Whales are adapted for diving to great depths. In addition to their streamlined bodies, they can slow their heart rate to conserve oxygen; blood is rerouted from tissue tolerant of water pressure to the heart and brain among other organs; haemoglobin and myoglobin store oxygen in body tissue; and they have twice
6384-478: The water. Upon striking an object in the water, the sound waves bounce back at the whale. These vibrations are received through fatty tissues in the jaw, which is then rerouted into the ear-bone and into the brain where the vibrations are interpreted. All toothed whales are opportunistic, meaning they will eat anything they can fit in their throat because they are unable to chew. These animals rely on their well-developed flippers and tail fin to propel themselves through
6468-488: The water; they swim by moving their fore-flippers and tail fin up and down. Whale ribs loosely articulate with their thoracic vertebrae at the proximal end, but do not form a rigid rib cage. This adaptation allows the chest to compress during deep dives as the pressure increases. Mysticetes consist of four families: rorquals (balaenopterids) , cetotheriids , right whales (balaenids) , and grey whales (eschrichtiids) . The main difference between each family of mysticete
6552-672: The water; they swim by moving their fore-flippers and tail fin up and down. Whale ribs loosely articulate with their thoracic vertebrae at the proximal end, but they do not form a rigid rib cage. This adaptation allows the chest to compress during deep dives as opposed to resisting the force of water pressure. Excluding dolphins and porpoises, odontocetes consist of four families: belugas and narwhals (monodontids) , sperm whales (physeterids) , dwarf and pygmy sperm whales (kogiids) , and beaked whales (ziphiids) . The differences between families of odontocetes include size, feeding adaptations and distribution. Monodontids consist of two species:
6636-537: The whales' closest terrestrial living relatives. Mysticetes are also known as baleen whales. They have a pair of blowholes side by side and lack teeth; instead they have baleen plates which form a sieve-like structure in the upper jaw made of keratin, which they use to filter plankton from the water. Some whales, such as the humpback, reside in the polar regions where they feed on a reliable source of schooling fish and krill . These animals rely on their well-developed flippers and tail fin to propel themselves through
6720-403: The world. The biodiversity of aquatic animals provide food, energy, and even jobs. Fresh water creates a hypotonic environment for aquatic organisms. This is problematic for organisms with pervious skins and gills , whose cell membranes may rupture if excess water is not excreted. Some protists accomplish this using contractile vacuoles , while freshwater fish excrete excess water via
6804-517: Was 35–40 °C (95–104 °F). Once in the Mediterranean, Leninsky Komsomol was given the mission of following an American ballistic missile submarine . On 8 September 1967, while transiting the Norwegian Sea , a fire broke out in the submarine's hydraulic system, and crew members in the compartment when the fire broke out had to evacuate the compartment. The flames spread to other parts of
6888-587: Was decommissioned in 1988. Since its retirement the K-3 has been docked at the Nerpa Shipyard, Murmansk The K-3 is set to become part of The Museum of Naval Glory in Kronstadt and is expected to be open for visitors by early 2023. 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
6972-437: Was estimated at USD 452 billion, comprising USD 157 billion for capture fisheries and USD 296 billion for aquaculture. Of the total 185 million tonnes of aquatic animals produced in 2022, about 164.6 million tonnes (89%) were destined for human consumption, equivalent to an estimated 20.7 kg per capita. The remaining 20.8 million tonnes were destined for non-food uses, to produce mainly fishmeal and fish oil. In 2022, China remained
7056-470: Was unavailable. Leninsky Komsomol was tasked with that patrol. She was assigned a new commander, Captain Second Rank Stepanov, and her executive officer arrived aboard only two hours before she put to sea. Whatever the initial material condition of the boat, the crew was not ready for sea. By the time they reached the Mediterranean, the air regeneration system had failed and the temperature on board
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