CLASSIFICATION OF WHALE (BALAENOPTERA)
PHYLUM :- CHORDATA (Notochord, dorsal tubular nerve cord present and gill slits present)
Group :- CRANIATA (Definite head. Cranium with brain present)
Sub-phylum :- VERTEBRATA (vertebral column present)
Division :- GNATHOSTOMATA (Jaws and paired appendages present)
Super class :- TETRAPODA (Paired limbs, lungs, bony skeleton and cornified skin)
Class :-MAMMALIA (Body covered with hairs. females have mammary glands)
Sub-class :- THERIA (Viviparous)
Infra class :- EUTHERIA (Placental mammals, vagina single)
Order :- CETACEA (Fish like aquatic mammal)
Genus : Balaenoptera
- Found in arctic and antarctic waters.
HABIT AND HABITAT
- Largest and heaviest mammal adapted for aquitic marine life. It migrates to temperate waters for breeding purposes.
GENERAL CHARACTERSTICS OF WHALE (BALAENOPTERA)
- Commonly called as blue whale because body is blue above and yellow below.
- Above whale has massive size measuring 35 meters in length and 1.5 lac kg in weight.
- Balaenoptera is longest whale and largest mammal flourishing very well.
- Body is divisible into small head, large trunk and tail.
- Body contains paddle.like forelimbs, dorsal fin and tail flukes.
- Whale contains fringed baleen consisting of two rows of transverse plates of keratin for filtering planktones.
- Tail flukes are like two forked lobe of tail fin of fish. They provide strong propulsive thrust allowing upward movement of flukes which cause farward movement of whale.
- Tail flukes are operated by strong muscles inserted into hind most vertebrae of tail fluke.
- Stability and balance is provided by the paddle like forelimbs acting as hydroplanes.
- Tail flukes and dorsal fins are neomorphus i.e., they are only folds of skin without any skeletal support but guided by strong muscles.
- Paddle-like forelimbs are adapted for swimming.
- Also called sulfur-bottom whale, the most massive animal ever to have lived, a species of baleen whale that weighs approximately 150 tons and may attain a length of more than 30 metres (98 feet). The largest accurately measured blue whale was a 29.5-metre female that weighed 180 metric tons (nearly 200 short [U.S.] tons), but there are reports of 33-metre catches that may have reached 200 metric tons. The heart of one blue whale was recorded at nearly 700 kg (about 1,500 pounds).
- The animal contains tail fluke and above features, hence it is whale.