@whale @WhaleTube

WhaleSea Animal

Whales are a widely distributed and diverse group of fully aquatic placental marine mammals. They are an informal grouping within the infraorder Cetacea, usually excluding dolphins and porpoises. Whales, dolphins and porpoises belong to the order Cetartiodactyla, which consists of even-toed ungulates.

Phylum: Chordata

Order: Artiodactyla

Lifespan: Blue whale: 80 – 90 years, Killer whale: 29 years

Mass: Blue whale: 50,000 – 150,000 kg, MORE Encyclopedia of Life

Length: Blue whale: 25 m, Killer whale: 6 – 8 m, MORE Encyclopedia of Life

Gestation period: Blue whale: 10 – 12 months

Whale, any of the larger species of aquatic mammals belonging to the order Cetacea. The term whale can be used in reference to any cetacean, including porpoises and dolphins, but in general it is applied to those more than 3 metres (10 feet) long.

An exception is the 2.7-metre dwarf sperm whale (Kogia simus), so called for its otherwise striking resemblance to its larger namesake. Whales are the heaviest known animals, living or fossil, reaching a maximum size in the blue whale (Balaenoptera musculus) of perhaps more than 30 metres and 200 metric tons (220 short [U.S.] tons).

Whales are distributed throughout the world’s oceans and seas, from the Equator to the polar ice, except for the landlocked Caspian and Aral seas. They are mammals, and they share the defining traits of

that group: they breathe air, are warm-blooded, give live birth, suckle their young on milk, and have hair. All are entirely aquatic, with specialized adaptations such as flippers and tail flukes for living in water.

Whales must surface regularly to breathe, evacuating their lungs more completely than most mammals in an almost explosive breath known as a blow. Blows are visible because water vapour in the whale’s hot breath condenses when the blow is released.

Despite living in a medium that has much greater thermal conduction characteristics than air, whales, like other mammals, must regulate their body temperature.

Hair, however, is restricted to the head, appearing mainly as isolated whiskers (vibrissae) near the mouth and blowhole. Blubber serves as an insulating layer to protect small whales from hypothermia.

Large whales have the opposite problem in that they can produce too much heat; they possess elaborate thermoregulation mechanisms to prevent overheating.

Biology Of Whale
Etymology and definitions

The word "whale" comes from the Old English hwæl, from Proto-Germanic *hwalaz, from Proto Indo European *(s)kwal-o-, meaning "large sea fish".

The Proto-Germanic *hwalaz is also the source of Old Saxon hwal, Old Norse hvalr, hvalfiskr, Swedish val, Middle Dutch wal, walvisc, Dutch walvis, Old High German wal, and German Wal.

The obsolete "whalefish" has a similar derivation, indicating a time when whales were thought to be fish.[citation needed] Other archaic English forms include wal, wale, whal, whalle, whaille, wheal, etc.

The term "whale" is sometimes used interchangeably with dolphins and porpoises, acting as a synonym for Cetacea. Six species of dolphins have the word "whale" in their name, collectively known as blackfish: the killer whale, the melon

-headed whale, the pygmy killer whale, the false killer whale, and the two species of pilot whales, all of which are classified under the family Delphinidae (oceanic dolphins). Each species has a different reason for it, for example, the killer whale was named "Ballena asesina" 'killer whale' by Spanish sailors.

The term "Great Whales" covers those currently regulated by the International Whaling Commission: the Odontoceti family Physeteridae (sperm whales); and the Mysticeti families Balaenidae (right and bowhead whales), Eschrichtiidae (grey whales), and some of the Balaenopteridae (Minke, Bryde's, Sei, Blue and Fin; not Eden's and Omura's whales).

Mysticetes
Mysticetes are also known as baleen whales. They have a pair of blowholes side-by-side and lack teeth; instead they have baleen plates which form a sieve-like structure in the upper jaw made of keratin, which they use to filter plankton from the water. Some whales, such as the humpback, reside in the polar regions where they feed on a reliable source of schooling fish and krill.

These animals rely on their well-developed flippers and tail fin to propel themselves through the water; they swim by moving their fore-flippers and tail fin up and down. Whale ribs loosely articulate with their thoracic vertebrae

at the proximal end, but do not form a rigid rib cage. This adaptation allows the chest to compress during deep dives as the pressure increases.

Mysticetes consist of four families: rorquals (balaenopterids), cetotheriids, right whales (balaenids), and grey whales (eschrichtiids).