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animals7.html
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Seals, sea lions, fur seals and walruses are all classed as pinnipeds.
The name is derived from the Latin for flap-footed and these marine
mammals are thought to have derived from bear-like ancestors which
entered the sea millions of years ago.
There are 33 species including 18 true seals, 5 sea lions, 9 fur
seals
and 1 walrus.
They have many adaptations to suit their aquatic lifestyle. Pinnipeds
are covered with thick skin and a dense layer of blubber to insulate
their bodies, and to aid buoyancy. They are streamlined and their
limbs have evolved into flippers to enable them to move quickly
through the water.
Fur seals are distinguished from true seals by the presence of
external
ears and the ability to bring their rear flippers underneath their
bodies,
to enable them to stand on all four limbs. For this reason, fur seals
are
more closely related to sea lions than true seals, and are more
capable
of moving on land.
True seals move clumsily on land, although some species can still
move faster than a human, by 'belly-hopping'.
Pinnipeds feed on a variety of foods including krill, fish,
crustaceans,
other pinnipeds and penguins. They are found throughout the world
and come ashore to breed and rest.
Many species of pinniped have suffered from commercial hunting.
They have been extensively killed for their skins, blubber and meat.
Some seals such as harp seals, are born with white pelts which were
prized in the fur trade. Nowadays, their greatest threats are decline
of
fish stocks due to over-fishing, pollution, disturbance, entanglement
in
marine debris and culling by fishery owners.
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