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  • Topic: Whale, Cetacea, Humpback whale
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Whale weighs as much as 20 elephants but lives beneath the sea. The blue

whale is Earth's largest animal. Larger than the largest of ancient

dinosaurs, blue whales can grow to be more than 100 feet (30 meters) long

and weigh nearly 150 tons. Not all whales are so large. The much smaller

pilot whale grows to about 28 feet (8.5 meters) in length. And dolphins,

which belong to the whale family, range only from 3 to 13 feet (1 to 4

meters). Although whales spend their lives in the sea, they are, like

humans, warm-blooded mammals. After a baby whale is born, it nurses on its

mother's milk, just like the young of land mammals.

Whales are members of the order Cetacea, along with dolphins, porpoises, and

the narwhal. There are two basic types of living cetaceans: baleen, or

whalebone, whales of the scientific suborder Mysticeti; and toothed whales

of the suborder Odontoceti.

General Characteristics

Whales live in all of the open seas of the world, though some occasionally

enter coastal waters. Some species, such as the white whale, or beluga, may

travel upstream in large rivers. Some species migrate with the seasons;

others remain year-round in the same habitats, where they find their

preferred food.

The present-day distribution and abundance of some species has been greatly

influenced by the commercial whaling industry. Whalers eliminated or greatly

reduced the numbers of some species of baleen whales in certain oceanic

regions where whales once frolicked in abundance. This is particularly true

in parts of the Arctic Ocean and the eastern North Atlantic Ocean, where the

blue whale was almost completely exterminated in the early 1900s. Some

species of whales, however, are numerous today in the Arctic and Antarctic


The skin of whales is usually black, gray, black and white, or all white.

Some, such as the blue whale, have skin that is bluish-gray. The surface of

the skin is smooth, but like other mammals, whales have hair. Hair first

appears while the fetal whale is still developing inside its mother's womb.

In adult whales, hair is confined primarily to a few bristles in the head

region and is largely absent over most of the body. Whales that live in

polar regions are insulated from the extreme cold by a layer of blubber, or

fat, enveloping their bodies.

Baleen Whales

The baleen whales include the family of right whales, Balaenidae, so named

because whalers considered them "just right" easy to kill and full of oil

and whalebone. Among these are the black right whale (Eubalaena glacialis)

of both northern and southern seas. Scientists believe that those in the

western North Atlantic may be gradually increasing in numbers. However,

populations in the eastern North Atlantic and in both the eastern and

western North Pacific show no signs of recovery, and only a few remain in

each area. An estimated 1,500 to 3,000 occur in the southern oceans, with

little evidence of a significant increase in population sizes in most areas.

Some scientists place the southern right whale in a separate species: E.

australis. Black right whales reach lengths of 70 feet (21 meters) and are

black on the upper body. The underside is sometimes paler in color. The

baleen plates in the mouth may be more than 8 feet (2.4 meters) long.

Toothed Whales

The toothed whales include more than 65 species in six different families.

Among these are the true dolphins (family Delphinidae), which includes the

pilot whales (genus Globicephala) and the killer whale (Orcinus orca),

largest of the oceanic dolphins. Killer whales prefer coastal waters to the

open ocean. They hunt in schools and, though relatively small at 30 feet (9

meters), will attack other whales two or three times their size.

Two other families include the true porpoises...
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