Stumble this page! |
|
| Images are copyrighted by their owners |
|
Dolphins, porpoises, and whales
Order : Cetacea
Thought to be once living on land, cetaceans have evolved to the aquatic life. Many cetaceans can dive for long periods and to great depths. Unlike humans, who can't dive too far down or stay under for too long or else too much nitrogen will be dissolved into our bodies, the cetaceans are not breathing pressurized air as is the scuba (self-contained underwater breathing apparatus) diver. The cetacean actually just holds its breath under water, so the air to be dissolved into its body, slowly decreases.The disease human divers can get from staying too long or too deep is called the caisson disease, altitude sickness, or the bends. A few cetaceans are believed to be the most intelligent non-primates and many have proportionately larger brains.
The order of cetaceans contains two sub-orders still in existence (the sub-order of ancient whales is extinct). These are Mysticeti (baleen whales) and the Odontoceti (toothed whales).
The sub-order of Baleen whales consists of 11 species, the very large whales. The Blue Whale (Balaenoptera musculus) is the largest mammal (up to 30 meters or about 90 feet). It is also the largest mammal to have ever lived that we know of. Baleen whales are not known to dive to great depths, the fin whales are recorded to dive the deepest of the baleen whales to a maximum of about 355 m (1,165 ft.). That's nothing compared to sperm whales which can dive to depths of over 2,133 meters (7,000 ft) and can stay underwater for close to two hours. Baleen whales dives last anywhere from 3 to 20 minutes or more depending on the species.
The sub-order of Odontoceti (toothed whales) is a much larger and more diverse group than the Baleen whales. It consists of 68 species which are small to medium in size, except for the sperm whales (the very large giant sperm whale reaches up to 18 m and weighs up to 53,000 kg). Like baleen whales, they make sounds, whistles and clicks, as a means of communication, and it is believed that these sounds are used for echolocation to find food and navigate. Toothed whales are social animals, orcas (killer whales) travel in social units called pods, containing one adult male, several adult breeding females and a number of sub-adults of both sexes. Sizes may vary from as few as 4 to as many as 40. Killer whales are most common in Arctic and Antarctic waters, but also occurs in all other oceans. They have an extremely varied diet, as far as animals living in the oceans are concerned, ranging from fish to birds, seals and even other whales.
Picture of orca was taken from http://www.captivitystinks.org/
Resources http://animaldiversity.ummz.umich.edu/site/accounts/information/Cetacea.html
http://www.nhm.org/research/mammals/dolporp/cetbends.html
http://science.howstuffworks.com/question101.htm
http://www.encyclopedia.com/html/d1/decompre.asp
http://www.seaworld.org/infobooks/Baleen/home.html
http://www.earthlife.net/mammals/welcome.html
Facts about the order Cetacea, the dolphins, porpoises, and whales
Cetacea is often broken down into two suborders, Mysticeti (Baleen whales), and Odontoceti (the toothed whales). (Full text)
[<NL Cetace(a) (see CET-, -ACEA)] CETACEA is a photographic collection of Boston Whalers in their natural habitat, occassionally in mock zoological style. (Full text)
A complete up-to-date taxonomical listing of all cetacean species, including all whales, is maintained at the Cetacea article. (Full text)
Jump to: navigation, search Whales are the largest species of exclusively aquatic mammals, members of the order Cetacea, which also includes dolphins and porpoises. (Full text)
(Redirected from Whales) Jump to: navigation, search Whales are the largest species of exclusively aquatic mammals, members of the order Cetacea, which also includes dolphins and porpoises. (Full text)
Baleen whales are the largest animals on earth, yet they feed on some of the smallest animals in the ocean. (Full text)
Cetacea is a project realized by Andrea Centazzo for the "Cetacea foundation of Riccione", several year ago to sensitizing the Institutions, Media and people on the extinction danger of the marine mammals in the Mediterranean Sea. (Full text)
Cetacea is a global provider of Wireless LAN and Mobile Communication System sales, service and installation. (Full text)
Web hosting and sponsorship by Vision Internet Limited Cetacea is currently on hiatus. (Full text)
The whole skull of such whales is highly modified. (Full text)
Whales are amongst the most enigmatic and fascinating of all creatures. (Full text)
World Wide Whales: Found in all the oceans of the world, whales are members of the Cetacea order of marine mammals, which also includes Dolphins and Porpoises. (Full text)
ZOOM WHALES - Enchanted Learning Software Zoom Whales Whales are large, magnificent, intelligent, aquatic mammals. (Full text)
A social group of whales is called a pod. (Full text)
LIVING IN THE OCEAN Whales are large, magnificent, intelligent, aquatic mammals. (Full text)
The range of Humpback whales is world-wide, but they are rarely seen in the Arctic Ocean. (Full text)
This devastation happened because the reproductive rate of whales is low and the monetary value of individual whales was high. (Full text)
Concern about whales is also addressed. (Full text)
Understand why some species of whales are in danger of becoming extinct. (Full text)
"Cetacea is no longer. (Full text)
Jump to: General, Art, Business, Computing, Medicine, Miscellaneous, Religion, Science, Slang, Sports, Tech, Phrases We found 12 dictionaries with English definitions that include the word cetacea: Tip: Click on the first link on a line below to go directly to a page where "cetacea" is defined. (Full text)
The order Cetacea is made up of the Whales, Dolphins, and Porpoises of the world. (Full text)
Mammalia Order The order Cetacea is represented in California by the following taxa: (Full text)
com Member Since: 2003-08-07 Camera: Canon Digital D60, Canon EOS G Rebel, Minolta Dimage 7, Canon PowerShot A80 Note: cetacea is a favorite of 6 members. (Full text)
The fossil record of whales is rich, and recent discoveries have shed much light on the origin of the Cetacea. (Full text)
Whales are Not the Major Causes of Dwindling Fish Stocks (Full text)
1. Cetacea, order Cetacea -- (an order of Eutheria)Cetacea
order Cetacea
(Source WordNet)
Links
http://animaldiversity.ummz.umich.edu/site/accounts/information/Cetacea.html
http://www.nhm.org/research/mammals/dolporp/cetbends.html
http://science.howstuffworks.com/question101.htm
http://www.encyclopedia.com/html/d1/decompre.asp
http://www.seaworld.org/infobooks/Baleen/home.html
http://www.earthlife.net/mammals/welcome.html