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Whale

378 bytes added, 22:45, 7 May 2013
revert to keep most of my edits, ignoring bits on "cetartiodactyl" nomenclature Karajou please see your talk page.
== Description ==
Whales are separated into the toothed whales , ''Odontocetes'' (which includes [[dolphin]]s, [[porpoise]]s, [[narwhal]]s, [[beaked whale]]s whales and [[sperm whale]]s), and the whalebone, or baleen, whales, also called ''Mysticetes''. The latter are mostly very large, which, instead of teeth, have baleen (whalebone) to filter small prey from the water; they are what people generally think of when the word whale is used. The whalebone whales include the rorquals - the [[blue whale]], fin whale, sei whale, Bryde's whale, [[minke whale]], [[grey and humpback whale]]; the [[humpback grey whale]]; and the various [[right whale]]s.
Although whales are famed for the massive size reached by some species, such as the blue whale (the largest animal to ever live), others are relatively small, like the pygmy right whale which grows to about 20 feet<ref>[http://www.acsonline.org/factpack/PygmyRightWhale.htm]American Cetacean Society website</ref>. Though whales have many traits in common with fish (including fins and tails) they are [[classification system|classified]] as [[mammal|mammals]] under the [[Linnaean taxonomy]] classification system because they breathe air and lactate. Whales have a number of remarkable features including:
* these extraordinary noises can travel for miles under water
* the females nurse their calves while swimming underwater
* the males have a unique cooling system for their internal reproductive organs, involving the circulation of cooled blood from the extremities directly around the [[testes]] before returning to the [[heart]]
* whales, along with humans and horses, are some of the few mammal species that do not possess [[baculum]] (penile bone)
* some mysticetes have two blow-holes, but others while odontocetes only have one
* the blow-holes pass air above water, yet resist intense pressure underwater
* they have massive brains, much larger than the brains of other mammals
=== Taxonomy ===
There are two kinds of whales: toothed whales of the suborder Odontoceti, and whalebone (baleen) whales of the suborder Mysticeti.
*'''Suborder ''Mysticeti'': Baleen whales'''::'''Family ''Balaenidae'': Right whales'''
::::Genus ''Balaena''
:::::Bowhead whale, ''Balaena mysticetus''
::::Genus ''Eubalaena''
:::::North Atlantic right whale, ''Eubalaena glacialis''
:::::North Pacific right whale, ''Eubalaena japonica''
:::::Southern right whale, ''Eubalaena australis''
::'''Family ''Balaenopteridae'': Rorquals''':::Subfamily ''Balaenopterinae''
::::Genus ''Balaenoptera''
:::::Antarctic minke whale, ''Balaenoptera bonaerensis''
:::::Fin whale, ''Balaenoptera physalus''
:::::Sei whale, ''Balaenoptera borealis''
:::Subfamily ''Megapterinae''
::::Genus ''Megaptera''
:::::Humpback whale, ''Megaptera novaeangliae''
::::Genus ''Eschrichtius''
:::::Gray whale, ''Eschrichtius robustus''
::'''Family ''Neobalaenidae'''''
::::Genus ''Caperea''
:::::Pygmy right whale, ''Caperea marginata''
*'''Suborder ''Odontoceti'': Toothed whales'''::'''Family ''Monodontidae'''''
::::Genus ''Delphinapterus''
:::::Beluga, ''Delphinapterus leucas''
::::Genus ''Monodon''
:::::Narwhal, ''Monodon monoceros''
::'''Family ''Physeteridae'': Sperm whales'''
::::Genus ''Physeter''
:::::Sperm whale, ''Physeter macrocephalus''
:::::Arnoux's beaked whale, ''Berardius arnuxii''
:::::Baird's beaked whale, ''Berardius bairdii''
:::Subfamily ''Hyperoodontidae''
::::Genus ''Hyperoodon''
:::::Northern bottlenose whale, ''Hyperoodon ampullatus''
::::Genus ''Ziphius''
:::::Cuvier's beaked whale, ''Ziphius cavirostris''
::'''Family ''Delphinidae'''''
::'''Family ''Phocoenidae'''''
== Origins ==
[[File:Whale_evolution.jpg]]The question of how whales and their relatives could have evolved from terrestrial [[mammal]]s has taxed evolutionary biologists since [[Charles Darwin|Darwin's]] suggestion that they may have evolved from ancient bears. <blockquote>"In North America the black bear was seen . . . swimming for hours with widely open mouth, thus catching, like a whale, insects in the water. Even in so extreme a case as this, if the supply of insects were constant, and if better adapted competitors did not already exist in the country, I can see no difficulty in a race of bears being rendered, by natural selection, more and more aquatic in their structure and habits, with larger and larger mouths, till a creature was produced as monstrous as a whale."</blockquote><ref>Charles Darwin, [http://www.gutenberg.org/ebooks/1228 Origin of species] 1st edition </ref>
In more recent times molecular and fossil evidence has been used to suggest that modern whales and their relatives arose from ancient [[Artiodactyla|artiodactyls]] (even-toed ungulates) with the closest living relative of all whales being [[hippopotamus|hippopotami]].<ref>[http://www.redorbit.com/news/science/41080/molecular_clock_divergence_estimates_and_the_fossil_record_of_cetartiodactyla/index.html] Theodore, JM (2004) Molecular Clock Divergence Estimates And The Fossil Record Of Cetartiodactyla <i> The Journal Of Paleontology</i> <b>78</b>:39-44</ref>
This kinship has been termed the whippo hypothesis.<ref>http://www.sciencenews.org/pages/pdfs/data/1999/15619/15619-10.pdf</ref>
Evolutionary biologists estimate the last ancestor of whales and hippos lived about 25 million years ago,<ref> [http://evolution.berkeley.edu/evosite/lines/IAtransitional.shtml] UCLA Berkley Understanding Evolution for Teachers website</ref> which . This theory of cetacean origins contrasts with the [[Young earth creationism|young earth creationist]] position that whales were [[creation|created]] about 6000 years ago, ''before'' land animals .<ref>Sarfati, Jonathan [http://www.creationontheweb.com/content/view/3834/106/ Whale evolution?] ''Refuting Evolution'', Chapter 5.</ref><ref>Batten, Don, [http://www.creationontheweb.com/content/view/1776 A whale of a tale?] ''Journal of Creation'' 8(1):2–3, April 1994.</ref><ref>Williams, Alexander, and Sarfati, Jonathan, [http://www.creationontheweb.com/content/view/1862 Not at all like a whale], ''Creation'' 27(2):20–22, March 2005.</ref>
==Whaling industry==
* Ellis, Richard. ''Men and Whales.'' (1991). 542 pp.
* Papastavrou, Vassili. ''Whale'' (DK Eyewitness Books) (2004) [http://www.amazon.com/Whale-Eyewitness-Books-Vassili-Papastavrou/dp/0756607396/ref=sr_1_3?ie=UTF8&s=books&qid=1226789849&sr=1-3 excerpt and text search]
* Stoett, Peter J. ''The International Politics of Whaling'' (1997) [http://www.questia.com/read/57120862?title=The%20International%20Politics%20of%20Whaling online edition] *Berta, Annalisa ''Return to the Sea: The Life and Evolutionary Times of Marine Mammals'' 2012
== References ==
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