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Pinniped
Pinnipeds (pronounced ), commonly known as seals, are a widely range (biology), distributed and diverse clade of carnivorous, fin-footed, semiaquatic, mostly marine mammals. They comprise the extant taxon, extant families Odobenidae (whose only living member is the walrus), Otariidae (the eared seals: sea lions and fur seals), and Phocidae (the earless seals, or true seals), with 34 extant species and more than 50 extinct species described from fossils. While seals were historically thought to have descended from two ancestral lines, molecular phylogenetics, molecular evidence supports them as a monophyletic group (descended from one ancestor). Pinnipeds belong to the suborder Caniformia of the order Carnivora; their closest living relatives are musteloids (Mustelidae, weasels, Procyonidae, raccoons, skunks and red pandas), having diverged about 50 million years ago. Seals range in size from the and Baikal seal to the and southern elephant seal. Several species exhibit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine Mammal
Marine mammals are mammals that rely on marine ecosystems for their existence. They include animals such as cetaceans, pinnipeds, sirenians, sea otters and polar bears. They are an informal group, unified only by their reliance on marine environments for feeding and survival. Marine mammal adaptation to an aquatic lifestyle varies considerably between species. Both cetaceans and sirenians are fully aquatic and therefore are obligate water dwellers. Pinnipeds are semiaquatic; they spend the majority of their time in the water but need to return to land for important activities such as mating, breeding in the wild, breeding and molting. Sea otters tend to live in kelp forests and estuaries. In contrast, the polar bear is mostly terrestrial and only go into the water on occasions of necessity, and are thus much less adapted to aquatic living. The diets of marine mammals vary considerably as well; some eat zooplankton, others eat fish, squid, shellfish, or seagrass, and a few eat ot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earless Seal
The earless seals, phocids, or true seals are one of the three main groups of mammals within the seal lineage, Pinnipedia. All true seals are members of the family Phocidae (). They are sometimes called crawling seals to distinguish them from the fur seals and sea lions of the family Eared seal, Otariidae. Seals live in the oceans of both hemispheres and, with the exception of the more tropical monk seals, are mostly confined to Polar region, polar, subpolar, and temperate climates. The Baikal seal is the only species of exclusively freshwater seal. Taxonomy and evolution Evolution The earliest known fossil earless seal is ''Noriphoca gaudini'' from the late Oligocene or earliest Miocene (Aquitanian (stage), Aquitanian) of Italy. Other early fossil phocids date from the mid-Miocene, 15 million years ago in the north Atlantic. Until recently, many researchers believed that phocids evolved separately from otariids and Walrus, odobenids; and that they evolved from otter-like ani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caniformia
Caniformia is a suborder within the order Carnivora consisting of "dog-like" carnivorans. They include Canidae, dogs (Wolf, wolves, foxes, etc.), bears, raccoons, and Mustelidae, mustelids. The Pinnipedia (pinniped, seals, walruses and sea lions) are also assigned to this group. The center of diversification for the Caniformia is North America and northern Eurasia. Caniformia stands in contrast to the other suborder of Carnivora, the Feliformia ("cat-like" carnivorans), the center of diversification of which was in Africa and United Nations geoscheme for Asia#Southern Asia, southern Asia. Description Most members of this group have nonretractile claws (the Fisher (animal), fisher, marten, sea otter (Forepaw, forepaws only), red panda, and Bassariscus astutus, ringtail, and some foxes have retractile or semi-retractile claws) and tend to be plantigrade (with the exception of the Canidae). Other traits that separate the Caniformia from the Feliformia is that caniforms have longer ja ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eared Seal
An eared seal, otariid, or otary is any member of the marine mammal family Otariidae, one of three groupings of pinnipeds. They comprise 15 extant species in seven genera (another species became extinct in the 1950s) and are commonly known either as sea lions or fur seals, distinct from true seals (phocids) and the walrus ( odobenids). Otariids are adapted to a semiaquatic lifestyle, feeding and migrating in the water, but breeding and resting on land or ice. They reside in subpolar, temperate, and equatorial waters throughout the Pacific and Southern Oceans, the southern Indian, and Atlantic Oceans. They are conspicuously absent in the north Atlantic. The words "otariid" and "otary" come from the Greek ' meaning "little ear", referring to the small but visible external ear flaps ( pinnae), which distinguishes them from the phocids. Evolution and taxonomy Morphological and molecular evidence supports a monophyletic origin of pinnipeds, sharing a common ancestor with M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Walrus
The walrus (''Odobenus rosmarus'') is a large pinniped marine mammal with discontinuous distribution about the North Pole in the Arctic Ocean and subarctic seas of the Northern Hemisphere. It is the only extant species in the family Odobenidae and genus ''Odobenus''. This species is subdivided into two subspecies: the Atlantic walrus (''O. r. rosmarus''), which lives in the Atlantic Ocean, and the Pacific walrus (''O. r. divergens''), which lives in the Pacific Ocean. Adult walrus are characterised by prominent tusks and whiskers, and considerable bulk: adult males in the Pacific can weigh more than and, among pinnipeds, are exceeded in size only by the two species of elephant seals. Walrus live mostly in shallow waters above the continental shelves, spending significant amounts of their lives on the sea ice looking for benthic bivalve molluscs. Walruses are relatively long-lived, social animals, and are considered to be a " keystone species" in the Arctic marine regio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steller Sea Lion
The Steller sea lion (''Eumetopias jubatus''), also known as Steller's sea lion or the northern sea lion, is a large, near-threatened species of sea lion, predominantly found in the coastal marine habitats of the northeast Pacific Ocean and the Pacific Northwest regions of North America, from north-central California to Oregon, Washington and British Columbia to Alaska. Its range continues across the Northern Pacific and the Aleutian Islands, all the way to Kamchatka, Magadan Oblast, and the Sea of Okhotsk, south to Honshu's northern coastline. It is the sole member of the genus ''Eumetopias'', and the largest of the so-called eared seals (Otariidae). Among pinnipeds, only the walrus and the two species of elephant seal are bigger. The species is named for the naturalist and explorer Georg Wilhelm Steller, who first described them in 1741. Steller sea lions have attracted considerable attention in recent decades, both from scientists and the general public, due to signific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southern Elephant Seal
The southern elephant seal (''Mirounga leonina'') is one of two species of elephant seals. It is the largest member of the clade Pinnipedia and the order Carnivora, as well as the largest extant marine mammal that is not a cetacean. It gets its name from its massive size and the large proboscis of the adult male, which is used to produce very loud roars, especially during the breeding season. A bull southern elephant seal is about 40% heavier than a male northern elephant seal (''Mirounga angustirostris''), which is nearly twice the weight of a male walrus (''Odobenus rosmarus''), or 6–7 times heavier than the largest living mostly terrestrial carnivorans, the Kodiak bear and the polar bear. Taxonomy The southern elephant seal was one of the many species originally described by Swedish zoologist Carl Linnaeus in the landmark 1758 10th edition of his ''Systema Naturae'', where it was given the binomial name of ''Phoca leonina''. John Edward Gray established the genus ''Mirou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carnivora
Carnivora ( ) is an order of placental mammals specialized primarily in eating flesh, whose members are formally referred to as carnivorans. The order Carnivora is the sixth largest order of mammals, comprising at least 279 species. Carnivorans are found on every major landmass and in a variety of habitats, ranging from the cold polar regions of Earth to the hyper-arid region of the Sahara Desert and the open seas. Carnivorans exhibit a wide array of body plans, varying greatly in size and shape. Carnivora are divided into two suborders, the Feliformia, containing the true felids and several animals; and the Caniformia, containing the true canids and many animals. The feliforms include the Felidae, Viverridae, hyena, and mongoose families, the majority of which live only in the Old World; cats are the only exception, occurring in the Old World and the New World, entering the Americas via the Bering land bridge. The caniforms include the Caninae, Procyonidae, bears, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grey Seal
The grey seal (''Halichoerus grypus'') is a large seal of the family Phocidae, which are commonly referred to as "true seals" or "earless seals". The only species classified in the genus ''Halichoerus'', it is found on both shores of the North Atlantic Ocean. In Latin, ''Halichoerus grypus'' means "hook-nosed sea pig". Its name is spelled gray seal in the United States; it is also known as Atlantic seal and the horsehead seal. Taxonomy There are two recognized subspecies of this seal: The type specimen of ''H. g. grypus'' ( Zoological Museum of Copenhagen specimen ZMUC M11-1525, caught in 1788 off the island of Amager, Danish part of the Baltic Sea) was believed lost for many years, but was rediscovered in 2016, and a DNA test showed it belonged to a Baltic Sea specimen rather than from Greenland, as had previously been assumed (because it was first described in Otto Fabricius' book on the animals in Greenland: ''Fauna Groenlandica''). The name ''H. g. g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desmatophocidae
Desmatophocidae is an extinct family of pinnipeds closely related to either the eared seals and walruses or to the earless seals. These animals were the first group of large-bodied pinnipeds to evolve, first appearing in the Early Miocene, with no direct modern descendants. Desmatophocids have only been found to live in the North Pacific, with fossils being found in Baja California, California, Oregon, Washington, and Japan. The group is generally known for having large orbits, bulbous cheek teeth Cheek teeth or postcanines comprise the molar and premolar teeth in mammals. Cheek teeth are multicuspidate (having many folds or tubercles). Mammals have multicuspidate molars (three in placentals, four in marsupials, in each jaw quadrant) and ..., and forelimbs similar to extant eared seals. Genera * '' Allodesmus'' * '' Atopotarus'' * '' Desmatophoca'' * '' Eodesmus'' References Prehistoric pinnipeds Miocene first appearances Miocene extinctions Prehistoric mammal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otarioidea
Otarioidea is a superfamily of pinnipeds that includes the families Odobenidae, Otariidae and their stem-relatives. In the past when the pinnipeds were considered to be a polyphyletic group of marine mammals, a few points of cranial and dental morphology suggested that the otarioids originated from a line of bears. One extinct family, Enaliarctidae, was postulated to be otarioids that were a transitional clade between Hemicyoninae (an extinct subfamily of dog-like bears) and Otariidae. Recent comprehensive studies have, however, since the 1990s found pinnipeds to be a monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ... clade of aquatic arctoids. There are a few authorities that place desmatophocids and odobenids as sister taxa to Phocidae in the clade Phocomorpha b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fur Seal
Fur seals are any of nine species of pinnipeds belonging to the subfamily Arctocephalinae in the family Otariidae. They are much more closely related to sea lions than Earless seal, true seals, and share with them external ears (Pinna (anatomy), pinnae), relatively long and muscular foreflippers, and the ability to walk on all fours. They are marked by their dense pelage, underfur, which made them a long-time object of commercial Seal hunting, hunting. Eight species belong to the genus ''Arctocephalus'' and are found primarily in the Southern Hemisphere, while a ninth species also sometimes called fur seal, the Northern fur seal (''Callorhinus ursinus''), belongs to a different genus and inhabits the North Pacific. The fur seals in ''Arctocephalus'' are more closely related to sea lions than they are to the Northern fur seal, but all three groups are more closely related to one another than they are to true seals. Taxonomy Fur seals and sea lions make up the family Otariidae. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
