Pinnipeds or fin-footed mammals are a widely distributed and diverse group of semiaquatic marine mammal

Mammal

Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...

s comprising the families

Family (biology)

In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Odobenidae

Odobenidae

Odobenidae is a family of Pinnipeds. The only living species is walrus.In the past, however, the group was much more diverse, and includes more than ten fossil genera.- Taxonomy :All genera, except Odobenus, are extinct.*Prototaria...

 (the walrus

Walrus

The walrus is a large flippered marine mammal with a discontinuous circumpolar distribution in the Arctic Ocean and sub-Arctic seas of the Northern Hemisphere. The walrus is the only living species in the Odobenidae family and Odobenus genus. It is subdivided into three subspecies: the Atlantic...

), Otariidae (eared seal

Eared Seal

The eared seals or otariids are marine mammals in the family Otariidae, one of three groupings of Pinnipeds. They comprise 16 species in seven genera commonly known either as sea lions or fur seals, distinct from true seals and the Walrus...

s, including sea lion

Sea Lion

Sea lions are pinnipeds characterized by external ear-flaps, long fore-flippers, the ability to walk on all fours, and short thick hair. Together with the fur seal, they comprise the family Otariidae, or eared seals. There are six extant and one extinct species in five genera...

s and fur seal

Fur seal

Fur seals are any of nine species of pinnipeds in the Otariidae family. One species, the northern fur seal inhabits the North Pacific, while seven species in the Arctocephalus genus are found primarily in the Southern hemisphere...

s), and Phocidae (earless seal

Earless seal

The true seals or earless seals are one of the three main groups of mammals within the seal superfamily, 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 Otariidae...

s).
Pinnipeds are typically sleek-bodied and barrel-shaped. Their bodies are well adapted to the aquatic habitat where they spend most of their lives. Their limbs consist of short, wide, flat flippers

Flipper (anatomy)

A flipper is a typically flat limb evolved for movement through water. Various creatures have evolved flippers, for example penguins , cetaceans A flipper is a typically flat limb evolved for movement through water. Various creatures have evolved flippers, for example penguins (also called...

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