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Pinniped

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	Topics Pinniped Topic Home Pinnipeds ("fin-feet", lit. "winged feet") or fin-footed mammals are a widely distributed and diverse group of semi-aquatic marine mammalMammal Overview The mammals are the class of vertebrate animals characterized by the presence of mammary glands, which in females produce mi... s comprising the families Odobenidae, Otariidae, and Phocidae. Formerly classified as a separate biological suborder, Pinnipedia is now sometimes considered a superfamily within CaniformiaCaniformia Caniformia, or Canoidea are a suborder within the order Carnivora.... , a suborder in the CarnivoraCarnivora The diverse order Carnivora includes over 260 placental mammals.... order. Evolution Recent molecular evidence suggests that pinnipeds evolved from a bearlike ancestor about 23 million years ago during the lateChattian The Chattian is the second and final of two stages of the Oligocene Epoch.... OligoceneOligocene The Oligocene epoch is a geologic period of time that extends from about 34 million to 23 million years before the present.... or early MioceneMiocene The Miocene epoch is a period of time that extends from about 23 to 5.3 million years before the present.... epochs, a transitional period between the warmer PaleogenePaleogene Paleogene period is a unit of geologic time that began 65 and ended 23 million years ago.... and cooler NeogeneNeogene Neogene Period is a unit of geologic time starting 23 million years ago.... periodPeriod (geology) A geologic period is a subdivision of geologic time that divides an era into smaller timeframes.... . The earliest fossil pinniped that had been found is EnaliarctosFacts About Enaliarctos *Enaliarctos* is an extinct genus of pinniped.... , which lived 24 – 22 million years ago. It is believed to have been a good swimmer, but to have been able to move on land as well as in water, more like an otter than like modern pinnipeds. There has been longstanding debate as to whether walruses diverged from a common otariid-phocid ancestor, or whether the phocids diverged before a common otariid-odobenid ancestor. The most recent evidence suggest that the latter hypothesis is more likely. Overview Pinnipeds are typically sleek-bodied, barrel-shaped and can be rather large. Their bodies are well adapted to the aquatic habitat where they spend most of their lives. Their limbs have evolved into short, wide, flat flippersFlipper (anatomy) A flipper is a digitless, typically flat limb evolved for movement through water.... whence the name (derived from the Latin pinna = "feather", "wing" or "fin", and ped = foot). The smallest pinniped, the Galapagos fur sealGalapagos Fur Seal The Galapagos Fur Seal is the smallest of all the pinnipeds.... , weighs about 30 kg (65 lbPound (mass) The pound is the name of a unit of mass in a number of different systems, including various systems of units of mass that f... ) when full-grown and is 1.2 m (4 ft) long; the largest, the male southern elephant sealSouthern Elephant Seal The Southern Elephant Seal is one of two species of elephant seal.... , is over 4 m (13 ft) long and weighs up to 2,200 kg (4,850 lb, more than 2 tonTon The word ton or tonne is derived from the Old English tunne, likely of Low Latin origin , with the spelling 'tonne... s). Otariidae Eared sealFacts About Eared Seal The eared seals , family Otariidae, are the fur seals and the sea lions.... s, also called "walking seals" and "otariids", include the animals commonly known as sea lionSea Lion A sea lion is any of several marine mammals of the family Otariidae.... s and fur sealFur seal Fur seals make up one of the two distinct groups of mammals called "seals".... s. These are vocal, social animals that are somewhat better adapted to terrestrial habitats with rear flippers that can turn forward such that they can move on all fours on land. Their foreflippers are larger than those of earless seals and are used as a primary source of maneuverablity in the water. Eared seals have external ears, as their name suggests, and more dog-like snouts, further distinguishing them from the true seals. While sea lions are generally larger than fur seals and lack the dense underfur of the latter, the long-standing division into subfamilies (Arctocephalinae and Otariinae for fur seals and sea lions respectively) has been shown to be unjustified in light of recent genetic evidence suggesting that several fur seal species are more closely related to some sea lions than other fur seals. The iconic ball-balancing circusCircus A circus is most commonly a traveling company of performers that may include acrobats, clowns, trained animals, hula hoopers... seal is generally some species of sea lion, most commonly a California sea lionCalifornia Sea Lion The California Sea Lion is a coastal sea lion of the northern Pacific Ocean.... . Phocidae Earless seals, also called “true seals" or "phocids" are the most diverse and widespread of the pinnipeds. They lack external ears and more streamlined snouts and are generally more aquatically adapted. They swim with efficient undulating whole body movements using their more developed rear flippers. The efficiency of their swimming and an array of other physiological adaptations make them better built for deep and long diving and long distance migrations. They are, however, very cumbersome on land, moving by wriggling their front flippers and abdominal muscles. True seals generally communicate by slapping the water and grunting, rather than vocalizing. Odobenidae The walrusWalrus Walruses are large semi-aquatic mammals that live in the cold Arctic seas of the Northern Hemisphere.... is an exclusively ArcticArctic The Arctic is the area around the Earth's North Pole, opposite the Antarctican area around the South Pole.... species - the sole surviving member of the once diverse and widespread Odobenidae family. They are easily recognized by their long tusks and great bulk (up to 2000 kg). While they share with otariids the ability to turn their rear flippers forward, their swimming is more reminiscent of that of true seals, relying more on sinuous whole body movements. They also lack external ears. Unlike eared seals and true seals, which feed primarily by hunting fish and squid in the water column, walrus generally prefer benthic invertebrates, in particular clamsCLaMS CLaMS is a modular chemistry transport model system developed at Research Centre Jlich, Germany.... . It is the development of the unique squirt and suck method of feeding on molluscs that differentiated the original walrus ancestor from the other pinniped lineages. There remains debate as to whether the walrus diverged from the eared seals before or after the true seals. Adaptations Flippers Pinnipeds have shorter limbs than most other mammals. As noted above, their limbs have evolved into flippers with true seals having more developed hind flippers and eared seals having more developed fore flippers. The walrus is intermediate between the two. A pinniped’s fingers and toes are bound together by a web of skin. They also have claws that are found either on the front flippers (earless seals) or back flippers (eared seals). Because water has a much higher densityDensity Density is a measure of mass per unit of volume.... than air, their flippers can be much smaller proportionately in relation to their size than the wings of a bird or bat. Additionally pinnipeds are essentially weightless in the waterNeutral buoyancy Neutral buoyancy is a condition in which a physical body's mass equals the mass it displaces in a surrounding medium.... , allowing them to come to a standstill, and perform aquabatic feats in water that would be impossible for atmospheric flying creatures. Oxygen conservation Pinnipeds can conserve oxygen for long period of time underwater. When the animal starts diving its heart rate slows to about one-tenth of the normal rate. The arteries squeeze shut and the sense organs and nervous system are the only organs to continue to receive a normal flow of blood. Pinnipeds are able to resist more pain and fatigue caused by lactic acid accumulation than other mammals. However, once they return to the water surface, they need time to recover and bring their body chemistry back to normal. Warmth To keep warm in cold waters, pinnipeds have a layer of blubber under their skin (which also provides buoyancy). The thickness depends on the species. The blubber is also a food reserve for the animal. Newborn pinnipeds have no blubber. Some pinnipeds can also can get warmth from their fur. The white coat of the infant harp sealHarp Seal The Harp Seal, is a marine mammal of the family Phocidae that is found in the North Atlantic and Arctic Oceans.... , can trap the energy of sunlight as heat. As noted above, fur seals have underfur. Molting Like other mammals, pinnipeds have to shed their fur once in a while. Eared seals shed more slowly than earless seals. Most earless seals spend time in the water while molting. Other adaptations A pinniped’s eyes are well adapted for seeing both above and below the water. When diving the animal has a clear membrane that covers and protects its eyes. In addition, its nostrils close automatically. Testicles and mammary glands are located in slits under the skin to keep the pinniped’s streamlined shape. They also have whiskerWhisker There are several kinds of whisker:... s to help navigate and sensors in their skull to absorb sounds underwater and trasmit them to the cochleaCochlea The cochlea is the auditory branch of the inner ear.... . Feeding All pinnipeds are carnivorous, eating fishFacts About Fish A fish is a water-dwelling vertebrate with gills, that remains so throughout its life.... , shellfishShellfish Shellfish is a culinary term for aquatic invertebrates used as food: molluscs, crustaceans, and echinoderms.... , squidSquid Squids are a large, diverse group of marine cephalopods.... , and other marine creatures. Most are generalist feeders, but some are specialists. For example; Ross SealRoss Seal The Ross Seal is a carnivorous seal of the family Phocidae and only species of the genus Ommatophoca.... s and Southern elephant sealSouthern Elephant Seal The Southern Elephant Seal is one of two species of elephant seal.... s mainly feed on squid. Crabeater sealCrabeater Seal Overview The Crabeater Seal, Lobodon carcinophagus, is one of the most remarkable, though least known, of the mammals of the worl... s eat mostly krill, and Ringed seals feed almost exclusively on crustaceanCrustacean The crustaceans are a large group of arthropods , usually treated as a subphylum .... s. Additionally, the WalrusWalrus Walruses are large semi-aquatic mammals that live in the cold Arctic seas of the Northern Hemisphere.... consumes molluscan prey items by sucking the soft parts from the shell. Some seals will even eat warm-blooded prey including other seals. The leopard sealLeopard Seal The Leopard Seal is one of the "true seals" belonging to the family Phocidae.... , which is probably the most carnivorous and predatory of all the pinnipeds, will eat penguinPenguin Penguins are an order of aquatic, flightless birds living in the Southern Hemisphere.... s as well as Crabeater and Ross Seals. The South American sea lionSouth American Sea Lion Otaria redirects here. If you are looking for the continent in Magic the Gathering, see Otaria.... also eats penguin as well as flying seabirds and young South American fur sealSouth American Fur Seal The South American Fur Seal is a species of fur seal that breeds on the coasts of Chile and Argentina.... s. Steller sea lions have been recorded eating Northern fur sealNorthern Fur Seal The Northern Fur Seal, Callorhinus ursinus, is an eared seal.... pups, Common sealFacts About Common Seal The Common Seal, Harbor Seal or Harbour Seal, *Phoca vitulina* is a true seal of the Northern Hemisphere... pups and birds. Almost all pinnipeds are potential prey for orcasOrcas Summary A code name for the Microsoft Visual Studio slated to be released after Visual Studio 2005.... and larger sharksSharks Sharks may refer to:Sharks, a group belonging to the cartilaginous fish... . Arctic species are an important component of polar bearPolar Bear The polar bear* , also known as the white bear, northern bear, or sea bear, is a large bear native to the ... diet. Reproduction Pinnipeds often come ashore or haul out on ice to breed, often travelling long distances from their feeding grounds to suitable matingMating In biology, mating is the pairing of opposite-sex or hermaphroditic internal fertilization animals for copulation and insemi... grounds with a high level of reproductive synchronyReproductive synchrony Reproductive synchrony, or synchronous spawning is a term used in evolutionary biology and behavioural ecology to desc... . Almost all pinnipeds are polygynous, i.e. males breed with up to several dozen females in a season. Males of many species, (e.g. elephant seals, South American sea lionSouth American Sea Lion Otaria redirects here. If you are looking for the continent in Magic the Gathering, see Otaria.... s and Northern fur sealNorthern Fur Seal The Northern Fur Seal, Callorhinus ursinus, is an eared seal.... s) aggressively defend groups of specific females, referred to as harems. Males of other species (e.g. most sea lions and Cape fur sealCape Fur Seal The Cape Fur Seal and the Australian Fur Seal are two subspecies of the Arctocephalus pusillus species of fur seal... s) defend territories on reproductive rookeries while females move freely between them. Some form of competition, either for females or territories, some of which can be violent, is an integral part of the male breeding strategy among most pinnipeds. Otariids, which are generally more land-adapted, tend to form major aggregations in the summer months on beaches or rocky outcrops. Consequently, their reproductive behavior is easier to observe and well studied. Walruses and many phocids, on the other hand, tend to form smaller aggregations, often in remote locations or on ice, and copulate in the water. Their reproductive behavior is therefore generally less well known. Females have a postpartum oestrus allowing them to mate soon after giving birth. Subsequent implantation of the embryoEmbryo An embryo is a multicellular diploid eukaryote in its earliest stage of development. ... is delayed thus removing the need to come ashore (haul-out) twice, once to give birth and again later to mate. After giving birth, mothers suckle their young for a variable length of time. Amongst the phocids, lactation varies from 4 to 50 days, whereas the otarids may lactate from 4 to 36 months. This reflects the fact that phocid feeding grounds tend to be a long way off-shore, so lactation is associated with maternal fastingFasting Fasting is the act of willingly abstaining from some or all food and in some cases drink, for a period of time.... . To compensate for the short lactation period, the fatFat Fats consist of a wide group of compounds that are generally soluble in organic solvents and largely insoluble in water.... content of phocid milkMilk Milk is the nutrient fluid produced by the mammary glands of female mammals .... is higher than in any other species of marine mammal (45 – 60% fat). After lactationLactation Lactation describes the secretion of milk from the mammary glands, the process of providing that milk to the young, and the ... most female phocids make extensive migratory movements to feeding grounds for intensive foraging to recoup depleted energy reserves. On the other hand, otariid feeding grounds are generally closer to shore and females go on foraging trips. Fat content of otariid milk is lower than that of the phocids, owing to the protracted lactation period (typically 25 – 50%). Protracted nursing also leads to the formation of social bonds. Taxonomy Family Odobenidae WalrusWalrus Walruses are large semi-aquatic mammals that live in the cold Arctic seas of the Northern Hemisphere.... , Odobenus rosmarus Imagotaria downsi (extinct) Family Otariidae Genus Arctocephalus Antarctic Fur SealAntarctic Fur Seal The Antarctic Fur Seal is one of seven seals in the genus Arctocephalus.... , A. gazella Guadalupe Fur SealGuadalupe Fur Seal The Guadalupe Fur Seal is a fur seal.... , A. townsendi Juan Fernandez Fur SealFacts About Juan Fernandez Fur Seal The Juan Fernandez Fur Seal is a fur seal that breeds on the Juan Fernandez Islands off the coast of Chile.... , A. philippii Galapagos Fur SealGalapagos Fur Seal The Galapagos Fur Seal is the smallest of all the pinnipeds.... , A. galapagoensis Cape Fur SealCape Fur Seal The Cape Fur Seal and the Australian Fur Seal are two subspecies of the Arctocephalus pusillus species of fur seal... , A. pusillus South African Fur Seal, A. pusillus pusillus Australian Fur Seal, A. pusillus doriferus New Zealand Fur SealNew Zealand Fur Seal Summary The New Zealand Fur Seal is a species of fur seal found around the south coast of Australia, the coast of the South Is... or Southern Fur Seal, A. forsteri Subantarctic Fur SealSubantarctic Fur Seal The Subantarctic Fur Seal is a fur seal found in the southern parts of the Indian and Atlantic Oceans.... , A. tropicalis South American Fur SealSouth American Fur Seal The South American Fur Seal is a species of fur seal that breeds on the coasts of Chile and Argentina.... , A. australis Genus Callorhinus Northern Fur SealNorthern Fur Seal The Northern Fur Seal, Callorhinus ursinus, is an eared seal.... , C. ursinus Genus Eumetopias Steller Sea Lion, E. jubatus Genus Neophoca Australian Sea LionAustralian Sea Lion The Australian Sea Lion is a species of sea lion that breeds only on the south coast of Australia.... , N. cinerea Genus Otaria South American Sea LionSouth American Sea Lion Otaria redirects here. If you are looking for the continent in Magic the Gathering, see Otaria.... , O. flavescens Genus Phocarctos New Zealand Sea LionNew Zealand Sea Lion The New Zealand Sea Lion or Hooker's Sea Lion is a species of sea lion that breeds around the coast of New Zealand's S... or Hooker's Sea Lion, P. hookeri Genus Zalophus California Sea LionCalifornia Sea Lion The California Sea Lion is a coastal sea lion of the northern Pacific Ocean.... , Z. californianus Japanese Sea LionJapanese Sea Lion The Japanese Sea Lion is thought to have gone extinct in the 1950s.... , Z. japonicus - extinct (1950s) Galapagos Sea LionGalápagos Sea Lion The Gal?pagos Sea Lion is a species of mammal in the Otariidae family endemic to Ecuador.... , Z. wollebaeki Family Phocidae Subfamily Monachinae Tribe Monachini Monachopsis (extinct) Pristiphoca (extinct) Properiptychus (extinct) Messiphoca (extinct) Mesotaria (extinct) Callophoca (extinct) Pliophoca (extinct) Pontophoca (extinct) Hawaiian Monk SealHawaiian Monk Seal The Hawaiian Monk Seal in the Family Phocidae, is an endangered marine mammal that is endemic to the warm, clear waters of t... , Monachus schauinslandi Mediterranean Monk SealMediterranean Monk Seal The Mediterranean Monk Seal is believed to be the world's rarest pinniped.... , Monachus monachus Caribbean Monk SealCaribbean Monk Seal The Caribbean Monk Seal or West Indian Monk Seal, the only seal ever known to be native to the Caribbean sea and the G... , Monachus tropicalis (probably extinct around 1950) Tribe Miroungini Northern Elephant SealNorthern Elephant Seal The Northern Elephant Seal is one of two species of elephant seal.... , Mirounga angustirostris Southern Elephant SealSouthern Elephant Seal The Southern Elephant Seal is one of two species of elephant seal.... , Mirounga leonina Tribe Lobodontini Monotherium wymani (extinct) Ross SealRoss Seal The Ross Seal is a carnivorous seal of the family Phocidae and only species of the genus Ommatophoca.... , Ommatophoca rossi Crabeater SealCrabeater Seal The Crabeater Seal, Lobodon carcinophagus, is one of the most remarkable, though least known, of the mammals of the worl... , Lobodon carcinophagus Leopard SealLeopard Seal The Leopard Seal is one of the "true seals" belonging to the family Phocidae.... , Hydrurga leptonyx Weddell SealWeddell Seal The Weddell Seal, a "true seal", is named after Sir James Weddell, commander of British sealing expeditions in the Weddell ... , Leptonychotes weddellii Swan-necked SealAcrophoca *Acrophoca longirostris* is an extinct species of pinniped.... , Acrophoca longirostris (extinct) Piscophoca pacifica (extinct) Homiphoca capensis (extinct) Subfamily Phocinae Kawas benegasorum (extinct) Leptophoca lenis (extinct) Preapusa (extinct) Cryptophoca (extinct) Bearded SealBearded Seal The bearded seal or square flipper seal, is a medium-sized seal that is found in and near to the Arctic Ocean.... , Erignathus barbatus Hooded SealHooded Seal The Hooded Seal is an arctic seal found only in the central and western North Atlantic ranging from Svalbard in the east to ... , Cystophora cristata Tribe Phocini Common SealCommon Seal The Common Seal, Harbor Seal or Harbour Seal, *Phoca vitulina* is a true seal of the Northern Hemisphere... or Harbor Seal, Phoca vitulina Spotted SealSpotted Seal The Spotted Seal, also known as the Larga seal, inhabits the ice and waters of the north Pacific Ocean and adjacent seas... or Larga Seal, Phoca largha Ringed SealRinged Seal The Ringed Seal or Jar Seal is an earless seal inhabiting the Arctic coasts.... , Pusa hispida (formerly Phoca hispida) NerpaNerpa The Nerpa or Baikal Seal is a species of earless seal endemic to Lake Baikal, a huge freshwater lake in Siberia near t... or Baikal Seal, Pusa sibirica (formerly Phoca sibirica) Caspian SealCaspian Seal Caspian seals, one of the smallest members of the "true seal" family, are unique in that they are found exclusively in the s... , Pusa caspica (formerly Phoca caspica) Harp SealHarp Seal The Harp Seal, is a marine mammal of the family Phocidae that is found in the North Atlantic and Arctic Oceans.... , Pagophilus groenlandica (formerly Phoca groenlandicus) Ribbon SealRibbon Seal The Ribbon Seal is a seal from the family Phocidae. It can be found in arctic regions. ... , Histriophoca fasciata (formerly Phoca fasciata) Phocanella (extinct) Platyphoca (extinct) Gryphoca (extinct) Grey SealGrey Seal The Grey Seal is found on both shores of the North Atlantic Ocean.... , Halichoerus grypus In culture Seals, sea lions, and walruses are popular animals in the media. They are often portrayed balancing beach balls on their noses and clapping with their flippers. Notable fictional seals include: Lou Seal: mascot for the San Francisco GiantsSan Francisco Giants The San Francisco Giants are a Major League Baseball team based in San Francisco, California.... Kotick: the main character in Rudyard KiplingRudyard Kipling Joseph Rudyard Kipling was a British author and poet best known today for his children's books: The Jungle Book , The... 's short story The White Seal, later made into a cartoon by Chuck JonesChuck Jones Charles Martin "Chuck" Jones was an American animator, cartoon artist, screenwriter, producer, and director of animated fil... Salty a seal that appears in the Disney cartoons Pluto's Playmate and Mickey and the Seal and later in Mickey's Mouseworks and House of Mouse The title character of AndreAndre (film) Andre is a 1994 feature film starring Tina Majorino and is about a child's encounter with a seal.... Whiskers from Manta and MorayManta and Moray Manta and Moray were a pair of amphibious superheroes who first appeared in a segment of the omnibus animated TV series Ta... Esmeralda the sea lion from the Disney version of 20,000 Leagues Under the Sea20,000 Leagues Under the Sea (1954 film) *20,000 Leagues Under the Sea* is a 1954 film starring Kirk Douglas as Ned Land, James Mason as Captain Nemo, Paul Lukas a... The San-XSan-X Summary San-X is a Japanese company that specializes in the creation, production and marketing of goods featuring anime-style anthro... company characters MamegomaMamegoma Mamegomaare several unusual Japanese characters that were created by the San-X company.... The main characters of Sparky, an escaped seal in the episode "Love and Sandy" from the 1964 television series FlipperFlipper (1964 TV series) Flipper was a television series that ran from 1964 till 1967 on NBC.... An unnamed robotic seal in Sonic the Hedgehog 2 (8-bit)Sonic the Hedgehog 2 (8-bit) *Sonic the Hedgehog 2* is a side-scrolling platform video game released by Sega for their Master System and Game Gear form... , who serves as the boss of the Aqua Lake Zone. A Pokémon creature Seel Because of the creature's name being coincidentally spelled the same as the unrelated word "sealSeal Seal or SEAL may refer to articles connected to a variety of meanings of the word:... " for a stamp, the confusion of one with the other is an occasional comic gag, as in "Christmas seal", or the live seal produced by Harpo MarxHarpo Marx Adolph Arthur Marx, popularly known as Harpo Marx, was one of the Marx Brothers, a group of Vaudeville and Broadway th... in Horse FeathersHorse Feathers *Horse Feathers* was the fourth Marx Brothers film.... when Groucho MarxGroucho Marx Julius Henry Marx, known as Groucho Marx , was an American comedian, working both with his siblings, the Marx Brothers... tries to find the legal seal for a contract document. Notable fictional walruses include: Chumley, the walrus sidekick to Tennessee Tuxedo (the Penguin) At least three professional sports teams in the San Francisco, CaliforniaSan Francisco, California The City and County of San Francisco is the fourth-largest city in California and the fourteenth-largest in the United State... , area have been known as the "SealsSan Francisco Seals The term San Francisco Seals can refer to any of three defunct professional sports teams based in San Francisco, California:... ". See also Cetaceans Sirenians Seal (disambiguation) NothosaurNothosaur Nothosaurs were Triassic marine sauropterygian reptiles that may have lived like seals of today, catching food in water but ... Vocal learningVocal learning Vocal learning is the ability of animals to modify vocal signals in form as a result of experience with those of other indiv...