Whales
Wikipedia tells us this about whales:
Whale is the common name for various marine mammals of the order Cetacea.
The term whale sometimes refers to all cetaceans, but more often it
excludes dolphins and porpoises, which belong to the suborder
Odontoceti (toothed whales). This suborder includes the sperm whale,
killer whale, pilot whatle and beluga whale.
The other cetacean suborder, Mysticeti (baleen whales),
comprises filter feeders who eat small organisms caught by
straining seawater through a comblike structure foung in the
mouth called baleen. This suborder includes the blue whale,
the humpback whale, the bowhead whale and the minke whale.
All cetaceans have forelimbs modified as fins, a tail with
horizontal flukes, and nasal openings (blowholes) on top of the
head.
But I like whales because they are:
- Huge!
- Friendly
- Can hold their breath for a long time
Whale Anatomy
There are some key parts to a whale's anatomy that I think are interesting.
- Blowhole: Whales breathe via blowholes; baleen whales have two and toothed whales have one. These are located on the top of the head, allowing the animal to remain almost completely submerged while breathing. Breathing involves expelling stale air (which is warm and moist), as well as some mucusand excess water from the blowhole, forming an upward, steamy spout, followed by inhalinf fresh air into the lungs. Spout shapes differ among species, which facilitates identification.
- Ears: The whale ear has specific adaptations to the marine environment. In humans, the middle ear works as an impedance equalizer between the outside air's low impedance and the cochlear fluid's high impedance. In aquatic mamals, such as whales, however, there is no great difference between the outer and inner ear. The whale is acoustically isolated from the skull by air-filled sinus pockets, which allow for greater directional hearing underwater.
Pictures!
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Whale Jumping out of water
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Killer whale jumping out of water
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