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MMM DEREK
<!--{{ Underconstruction }}
{{ in use }}-->
{{Taxobox
| name = Beavers
| fossil_range = Late [[Miocene]] – Recent
| image = Beaver.jpg
| image_width = 200px
| image_caption = [[American Beaver]]
| regnum = [[Animal]]ia
| phylum = [[Chordate|Chordata]]
| classis = [[Mammal]]ia
| ordo = [[Rodent]]ia
| familia = [[Castoridae]]
| genus = '''''Castor'''''
| genus_authority = [[Carolus Linnaeus|Linnaeus]], 1758
| subdivision_ranks = [[Species]]
| subdivision = ''[[American Beaver|C. canadensis]]''<br>''[[European Beaver|C. fiber]]''<br>†''[[Kellogg's Beaver|C. californicus]]''
}}
'''Beavers''' are semi-aquatic [[rodent]]s native to [[North America]] and [[Europe]]. They are the only living members of the [[family (biology)|family]] [[Castoridae]], which contains a single [[genus]], '''''Castor'''''. [[genetics|Genetic]] [[research]] has shown the European and North American beaver populations to be distinct [[species]] and that [[Hybrid (biology)|hybrid]]ization is unlikely.

== General ==

[[Image:Biberschaedel-drawing.jpg|thumb|right|A beaver [[skull]]]]
Beavers are best known for their natural trait of building [[dam]]s in [[river]]s and [[stream]]s, and building their homes (known as '''beaver lodges''') in the resulting [[pond]]. They are the second-largest rodent in the world (after the [[capybara]]).

They are also known for their "danger signal": when startled or frightened, a swimming beaver will rapidly dive while forcefully slapping the water with its broad tail. This creates a loud 'slap', audible over large distances above and below water. This noise serves as a warning to other beavers in the area. Once a beaver has made this danger signal, all nearby beavers will dive and may not reemerge for some time. Although this happens rarely, a frightened beaver may attack a human.<ref>http://www.thelocal.se/11544/20080505/ Matilda, 4, bitten by beaver</ref>

[[Image:Beavertracks.JPG|thumb|left|150px|Beaver tracks in snow, in [[Ontario]]. Hind paws approx. 20&nbsp;cm long.]]

Fossil remains of beavers are found in the peat and other superficial deposits of England and the continent of Europe; while in the [[Pleistocene]] formations of England and Siberia occur remains of a giant extinct beaver, ''Trogontherium cuvieri'', representing a genus by itself.

Beavers have webbed hind-feet, and a broad, scaly tail. They have poor eyesight, but a keen sense of hearing, smell, and touch.

Beavers continue to grow throughout life. Adult [[specimen]]s weighing over 25 [[kilogram|kg]] (55 lb) are not uncommon. Females are as large as or larger than males of the same age, which is uncommon among [[mammal]]s.

===Etymology===
The word is descended from the [[Proto-Indo-European language|Proto-Indo-European]] name of the animal, cf. Sanskrit ''babhru's,'' brown, the great ichneumon, Lat. ''fiber,'' Ger. ''Biber,'' Swed. ''bäver,'' Russ. ''bobr';'' the root ''bhru'' has given "brown," and, through Romanic, "bronze" and "burnish."<ref name="EB11">Encyclopedia Brittanica 11th Edn</ref>

==Species ==
Beavers are closely related to [[squirrel]]s (Sciuridae), agreeing in certain structural peculiarities of the lower jaw and skull. In the Sciuridae the two main bones (tibia and fibula) of the lower half of the leg are quite separate, the tail is round and hairy, and the habitats are arboreal and terrestrial. In the beavers or Castoridae these bones are in close contact at their lower ends, the tail is depressed, expanded and scaly, and their habitats are aquatic.<ref name="EB11"/>

Both European and American beavers grow to about 2 feet long (plus 10 inches of tail). They are essentially aquatic in their habits, never travelling by land unless driven by necessity. They are mainly nocturnal, and subsist chiefly on bark and twigs or the roots of water plants.

===European Beaver===

[[Image:Beaver pho34.jpg|200 px|thumb|A European Beaver]]
The [[European Beaver]] (''Castor fiber'') was hunted almost to [[extinction]] in Europe, both for fur and for ''[[castoreum]]'', a secretion of its scent gland believed to have medicinal properties. However, the beaver is now being re-introduced throughout Europe. Several thousand live on the [[Elbe]], the [[Rhone River|Rhone]] and in parts of [[Scandinavia]]. A thriving community lives in north east [[Poland]], and the European Beaver also returned to the [[Morava River]] banks in [[Slovakia]] and the [[Czech Republic]]. They have been [[reintroduction|reintroduced]] in [[Bavaria]], [[Austria]], [[The Netherlands]] and [[Serbia]] ([[Zasavica]] bog) and are spreading to new locations.

The beaver became extinct in [[Great Britain]] in the [[sixteenth century]]: [[Giraldus Cambrensis]] reported in 1188 (''Itinerarium'' ii.iii) that it was to be found only in the [[Teifi]] in [[Wales]] and in one river in [[Scotland]], though his observations are clearly [[first hand]]. In October 2005, six European beavers were re-introduced to Britain in Lower Mill Estate in [[Gloucestershire]]; in July of 2007 a colony of four European beavers was established at [[Martin Mere]] in [[Lancashire]],<ref>{{cite news |url=http://news.bbc.co.uk/1/hi/england/lancashire/6291260.stm |title=Beavers are back after 500 years |date=2007-7-11 |publisher=[[BBC News]]}}</ref> and there are plans for re-introductions in Scotland and Wales.<ref>[http://www.msn.co.uk/htx/returnofthebeaver/ Return of the Beavers] at [[MSN|MSN.co.uk]]</ref><ref>{{cite web |url = http://news.bbc.co.uk/1/hi/scotland/7158210.stm| publisher = [[BBC]]|title = Beavers could be released in 2009| date = 2007-12-24}}</ref>

===American Beaver===

[[Image:Castor canadensis.jpg|200 px|thumb|An American Beaver]]
The [[American Beaver]] ''(Castor canadensis)'', also called Canadian Beaver (which is also the name of a subspecies), or simply Beaver in North America, is native to Canada, much of the United States and parts of northern Mexico. The chief feature distinguishing ''C. canadensis'' from '' C. fiber'' is the form of the nasal bones of the skull.<ref name="EB11"/> This species was introduced to the Argentine and Chilean Tierra del Fuego, as well as Finland, France, Poland and Russia.

The American beaver's preferred food{{Fact|date=October 2007}}is the water-lily (''[[Nuphar luteum]]''), which bears a resemblance to a [[cabbage]]-stalk, and grows at the bottom of lakes and rivers. Beavers also gnaw the bark of birch, [[poplar]] and willow trees; but during the summer a more varied herbage, with the addition of berries, is consumed. [[Image:American Beaver.jpg|thumb|left|200 px|American Beaver.]]

These animals are often trapped for their fur. During the early 19th century, trapping eliminated this animal from large portions of its original range. However, through trap and transfer and habitat conservation it made a nearly complete recovery by the 1940s. Beaver furs were used to make clothing and top-hats. Much of the early exploration of North America was driven by the quest for this animal's fur. Native peoples and early settlers also ate this animal's meat. The current beaver population has been estimated to be 10 to 15 million; one estimate claims that there may at one time have been as many as 90 million<ref>Seton-Thompson, cited in {{cite book
| last =Sun
| first =Lixing
| authorlink =
| coauthors =Dietland Müller-Schwarze
| title =''The Beaver: Natural History of a Wetlands Engineer''
| publisher =Cornell University Press
| date =2003
| location =
| pages =
| url =
| doi =
| id =
| isbn = 080144098X}} pp97-98; but note that to arrive at this figure he assumed a population density throughout the range equivalent to that in [[Algonquin Park]]</ref>

===Giant beaver===
The North American [[Giant beaver]] (''Castoroides ohioensis'') was one of largest rodents that ever [[evolution|evolved]]. It disappeared along with other large mammals in the [[Holocene extinction event]], which began about 13,000 years ago. Since then it has not changed much in the evolution cycle.

==Habitat==

The habitat of the beaver is the [[riparian zone]] inclusive of stream bed. The actions of beavers for hundreds of thousands of years in the [[Northern Hemisphere]] have kept these watery systems healthy and in good repair, although a human observing all the downed trees might think that the beavers were doing just the opposite.

The beaver works as a [[keystone species]] in an [[ecosystem]] by creating [[wetlands]] that are used by many other species. Next to humans, no other extant animal appears to do more to shape its landscape{{Fact|date=May 2007}}.

===The dam's primary role: the beaver's home===

'''Beaver dams''' are created both as a protection against predators, such as [[coyote]]s, [[wolf|wolves]] and [[bear]]s, and to provide easy access to food during winter. Beavers always work at night and are prolific builders, carrying mud and stones with their fore-paws and timber between their teeth. Because of this, destroying a beaver dam without removing the beavers is difficult, especially if the dam is downstream of an active lodge. Beavers can rebuild such primary dams overnight, though they may not defend secondary dams as vigorously.

===Shape of dam===

[[Image:BeaverDam 8409.jpg|left|thumb|300px|[[Lassen Volcanic National Park]].]]
A dam's shape depends on the strength of the stream's current. Relatively still water encourages dams that are almost straight; while dams in stronger currents are curved, with the convexity pointing upstream. The beavers use [[driftwood]], green willows, [[birch]] and poplars; and they mix in mud and stones in ways that contribute to the dam's strength.

Beavers have been known to build very large dams.<ref>[http://abob.libs.uga.edu/bobk/bbeavdam.html Big Beaver Dam on Grand Island, Lake Superior<!-- Bot generated title -->]</ref> The largest known was discovered by satellite imagery in Northern Alberta in 2007, approximately 850 meters (2790 feet) long <ref>[http://www.geostrategis.com/p_beavers-longestdam.htm<!-- Bot generated title -->]</ref>, beating the previous record holder found near Three Forks, Montana, at 2,140 feet long, 14 feet high, and 23 feet thick at the base.<ref>[http://home.earthlink.net/~scouters2/beaver.html beaver.html<!-- Bot generated title -->]</ref> When objectionable beaver flooding occurs, modern water level control devices can be installed for a cost-effective and environmentally sound solution. Unwanted damage to trees can be prevented by wrapping chicken wire or sheet metal around the base of trees.<ref>[http://www.BeaversWW.org Beavers: Wetlands & Wildlife<!-- Bot generated title -->]</ref>

[[Image:117-1715 IMG.JPG|250px|right|thumb|Canoeists try unsuccessfully to run a beaver dam in [[Algonquin Park]]. The dam is about 1 m high.]]
"In places," writes Hearne, "which have been long frequented by beavers undisturbed, their dams, by frequent repairing, become a solid bank, capable of resisting a great force both of ice and water; and as the willow, poplar and birch generally take root and shoot up, they by degrees form a kind of regular planted hedge, which I have seen in some places so tall that birds have built their nests among the branches."{{Fact|date=November 2007}}

===Stimulus for dam-building ===

It is primarily prolonged exposure to the sound of water in motion that stimulates the beavers to build. However, studies involving beaver habitual activities have indicated that beavers may respond to an array of stimuli, not just the sound of running water. In two experiments Wilson (1971) and Richard (1967, 1980) demonstrate that, although beavers will pile material close to a loudspeaker emitting sounds of water running,<ref>[http://www.naturealmanac.com/archive/beaver_dams/beaver_dams.html 'Why Beavers Build Dams' at Natural Events Almanac]</ref> they only do so after a considerable period of time. Additionally the beavers, when faced with a pipe allowing water to pass through their dam, eventually stopped the flow of water by plugging the pipe with mud and sticks. The beavers were observed to do this even when the pipe extended several meters upstream and near the bottom of the stream and thus produced no sound of running water. Beavers normally repair damage to the dam and build it higher as long as the sound continues. However, in times of high water, they often allow spillways in the dam to flow freely.

=== Disruption by dams===

[[Image:Beaver signs.JPG|250px|left|thumb|Trees, up to 250 mm (10 inches) in diameter, felled by beavers in one night.]]
[[Image:Abandonedbeavertree.JPG|250|right|thumb|A tree abandoned by beavers, presumably too large]]
[[Image:Beaver dam in Tierra del Fuego.jpg|left|thumb|250px|[[Tierra del Fuego]]]]

Beaver dams can be disruptive; the flooding can cause extensive property damage, and when the flooding occurs next to a railroad roadbed, it can cause derailments by washing-out under the tracks, or when a beaver dam bursts and the resulting flash flood overwhelms a culvert. This disruption is not limited to human geography; beavers can destroy nesting habitat for endangered species, and often destroy mature trees for which they have no use.
Introduced to an area without its natural predators, as in [[Tierra del Fuego]], beavers have flooded thousands of acres of land and are considered an unstoppable plague. One notable difference in Tierra del Fuego from most of North America is that the trees found in Tierra del Fuego do not [[coppicing|coppice]] as do willows, poplars, aspens, and other North American trees. Thus the "damage" by the beavers seems more severe.

=== Benefits of dams compared to disruption===

On the other hand, dam building is extremely beneficial in restoring wetlands. Such wetland benefits include flood control downstream, biodiversity (by providing habitat for many rare as well as common species), and water cleansing, both by the breakdown of toxins such as pesticides and the retention of silt by beaver dams. Over the eons, this collection of silt produces the rich bottom land so sought after by farmers. Beaver dams also reduce erosion as well as decrease the turbidity that is a limiting factor for much aquatic life. While beavers can create damage, part of the problem is one of perception and time scale. Such damage as the undermining of a roadway or the drowning of some trees is very visible shortly after the beginning of beavers' activity in an area. The benefits, mentioned below, are long-term and not easily seen except by someone who is monitoring a catchment and realizes the beneficial effects of beaver dams.

===The dam's role in the stream's lifecycle===
[[Image:Broken Beaver Dam.jpg|thumb|right|200px|Drained beaver dam in [[Allegany State Park]].]]

==== Wetland creation ====

If a beaver pond becomes too shallow due to the settling of sediment, or if the tree supply is depleted, beavers will abandon the site. Eventually the dam will be breached and the water will drain out. The rich thick layer of silt, branches, and dead leaves behind the old dam is the ideal habitat for wetland species. Many of them will have been on the fringes of the pond. [[Wetlands]] have significant environmental benefits.

==== The grazing meadow (vega) ====

As the wetland fills and dries out, pasture species colonize it and it becomes a meadow suitable for grazing. In an area with nothing but forest down to the stream edge, this provides a valuable niche for many animals which otherwise would be excluded.

==== The riverine forest ====

Finally the meadow will be colonized by riverine trees, typically aspens, willows and such species which are favoured by the beaver. Beavers are then likely to recolonize the area, and the cycle begins again.

===The dam's beneficial ecological effects ===
==== Bottom land ====

Each time the stream lifecycle repeats itself another layer of rich organic soil is added to the bottom of the valley. The valley slowly fills and the flat area at the bottom gets wider. Research is sparse on this topic, but it seems likely that much of the fabled bottom land in North America was created, or at least added to, by the efforts of the generations of beavers that lived there.

==== Flood control ====

A beaver dam has a certain amount of [[freeboard]] above the water level. When heavy rains occur, the pond fills up and the dam gradually releases the extra stored water. Often this is all that is necessary to reduce the height of the flood wave moving down the river, and will reduce or eliminate damage to human structures. Flood control is achieved in other ways as well. The surface of any stream intersects the surrounding water table. By raising the stream level, the gradient of the surface of the water table above the beaver dam is reduced, and water near the beaver dam flows more slowly into the stream. This further helps in reducing flood waves, and increases water flow when there is no rain. Beaver dams also smooth out water flow by increasing the area wetted by the stream. This allows more water to seep into the ground where its flow is slowed. This water eventually finds its way back to the stream. Rivers with beaver dams in their head waters have lower high water and higher low water levels.

==== Nutrient removal ====

The removal of nutrients from the stream flow by beaver ponds is an interesting and very valuable process. Farming along the banks of rivers often increases the loads of phosphates, nitrates and other nutrients, causing problems downstream when this water is extracted for drinking. Besides silt, the beaver dam collects twigs and branches from the beavers' activity and leaves, notably in the fall. The main component of this material is [[cellulose]], a [[polymer]] of [[β-glucose]] [[monomers]] (This creates a more crystalline structure than is found in [[starch]], which is composed of [[α-glucose]] monomers. Cellulose is a type of [[polysaccharide]].) Many bacteria produce cellulase which can split off the [[glucose]] and use it for energy. Just as algae get their energy from sunlight, these bacteria get their energy from cellulose, and they form the base of a very similar food chain. However, a source of energy is not enough for growth. These bacterial populations face serious shortages of nitrous and phosporous compounds, and will absorb these nutrients as they pass by in the water stream. In this way, these and other nutrients are fixed into the beaver pond and the surrounding ecology, and are removed from the stream.

==== Pesticide and herbicide removal ====

Agriculture also introduces herbicides and pesticides into our streams. Bacteria are an extremely variable lot and some of these [[toxicant]]s are metabolized and decomposed by the bacteria in the cellulose-rich bottom of a beaver dam.

==== Denitrification ====

Some scientists believe that the nitrate cascade, the production of far more fixed nitrogen than the natural cycles can turn back into nitrogen gas, may be as much of a problem to our ecology as carbon dioxide production. It is likely, but not proven, that beaver dams along a stream may contribute to [[denitrification]] (the conversion of nitrogen compounds back into nitrogen). In sewage plants, denitrification is achieved by passing the water through successive aerobic and anaerobic stages. Under a beaver dam, as the water seeps down into the soil, the oxygen is consumed by the fauna in the rich organic layer. At some point all the oxygen is used up and the soil becomes anaerobic. This water eventually finds its way back into the aerobic stream and into another beaver dam. This aerobic, anaerobic cycle continues all the way down the stream and denitrification is a likely result.

===Beavers and salmon===
Beaver dams are a nursery for salmon. An early indication of this was seen following the 1818 agreement between the British government of Canada and the government of America allowing Americans access to the Columbia watershed. The Hudson's Bay Company, in a fit of pique sent word to its trappers to extirpate the fur bearing animals in the area. The beaver was the first to go. Salmon runs fell precipitously in the following years even though, at that time, none of the factors were extant that we associate with the decline of salmon runs.<ref>[http://www.nwcouncil.org/history/Beavers.asp 'Beavers' at The Northwest Power and Conservation Council]</ref>

The functions of beaver dams in increasing salmon runs are many. They provide deep enough water for the juvenile salmon to hide from predatory wading birds. They trap nutrients in their ecology and notably the huge nutrient pulse represented by the migration of the adult salmon upstream. These nutrients help feed the juveniles after they finish their yoke. They provide quiet water so that the young salmon can put energy into growth rather than into fighting currents and larger smolt with a food reserve have a better chance when they reach the sea. And beaver dams keep the water clear which favours all the salmonoids, trout included.

===Lodges=== <!-- This section is linked from [[Beaver lodge]] -->
[[Image:Beaverlodge.JPG|thumb|right|250px|Beaver lodge, approx. 20-foot diameter. [[Ontario, Canada]]]]

The ponds created by well-maintained dams help isolate the beavers' home, their ''lodge'', which is also created from severed branches and mud. The beavers cover their lodges late every autumn with fresh mud which freezes when the frost sets in. The mud becomes almost as hard as stone, so that neither wolves nor [[wolverine]]s can get in.

The lodge has underwater entrances to make entry nearly impossible for any other animal (however, [[musk rat|muskrats]] have been seen living inside beaver lodges with the beavers who made it). A very small amount of the lodge is actually used as a living area. Contrary to popular belief, beavers actually dig out their den with an underwater entrance after they finish building the dam and lodge structure. There are typically two dens within the lodge, one for drying off after exiting the water, and another, drier one where the family actually lives.

Their houses are formed of the same materials as the dams, with little order or regularity of structure, and seldom contain more than four old, and six or eight young beavers. Sometimes some of the larger houses have one or more partitions, but these are only posts of the main building left by the builders to support the roof, for the apartments have usually no communication with each other except by water.

When the ice breaks up in spring they always leave their embankments, and rove about until a little before fall, when they return to their old habitations, and lay in their winter stock of wood. They seldom begin to repair the houses till the frost sets in, and never finish the outer coating till the cold becomes severe. When they erect a new habitation they fell the wood early in summer, but seldom begin building till towards the end of August.

===Invasiveness===
Beavers can create serious damage when spread outside of their natural environment, and are therefore considered in some places as pests or [[invasive species]]. For example, in the 1940s, beavers were brought to the island of [[Tierra Del Fuego]] in southern [[Argentina]], for commercial fur production. However, the project failed and the beavers were released into the wild. Having no natural predators in their new environment, they quickly spread throughout the island, reaching a number of 100,000 individuals within just 50 years (when released into the wild there were only a few pairs). They are now considered a serious invasive species on the island, due to their massive destruction of forest trees, and efforts are being made for their eradication.<ref>[http://edition.cnn.com/NATURE/9907/09/argentina.beaver/ CNN - Argentina eager to rid island of beavers - July 9, 1999<!-- Bot generated title -->]</ref>

==Commercial uses==
Beaver pelts were used for [[barter (economics)|barter]] by [[Indigenous peoples of the Americas|Native Americans]] in the [[17th century]] to gain European goods. They were then shipped back to Great Britain and [[France]] where they were made into clothing items. Widespread hunting and trapping of beavers led to their endangerment. Eventually, the [[fur trade]] fell apart due to declining demand in Europe and the takeover of trapping grounds to support the growing agriculture sector. A small resurgence in beaver trapping has occurred in some areas where there is an over-population of beaver; trapping is only done when the fur is of value, and normally the remainder of the animal is also utilized as animal feed. The only fur in North America which surpassed the beaver's in commercial value was that of the silver morph [[red fox]], which was said to be forty times more valuable.<ref name="NEC">{{cite book | author = Morton, Thomas | title = New English Canaan: Or, New Canaan (Research Library of Colonial Americana) | year = 1972 | pages = pp.188 | id = ISBN 0405033095}}</ref>

Both beaver testicles and [[castoreum]], a bitter-tasting secretion with a slightly fetid odor contained in dried preputial or vaginal follicles of male or female beaver, have been articles of trade for use in traditional medicine. [[Yupik]] ([[Eskimo]]) medicine used dried beaver testicles like willow bark to relieve pain.<ref>{{cite web|url=http://tundramedicinedreams.blogspot.com/2006/08/yupik-eskimo-home-remedies.html|title=Yupik Eskimo home remedies|accessdate=2007-06-17}}</ref> Beaver testicles were exported from [[Levant]] (a region centered on [[Israel]]) from the tenth to nineteenth century.<ref>PMID 12576209</ref> [[Claudius Aelianus]] comically described beavers chewing off their testicles to preserve themselves from hunters.<ref>{{cite web|url=http://nestorscup.blogspot.com/2007/06/claudius-aelianus-beaver-testicles-and.html|title=Claudius Aelianus: Beaver Testicles and Red-Hot Feline Semen}}</ref> European beavers (''[[Castor fiber]]'') were eventually hunted nearly to extinction in part for the production of castoreum, which as used as an [[analgesic]], [[anti-inflammatory]], and [[antipyretic]]. Castoreum was described in the 1911 [[British Pharmaceutical Codex]] for use in [[dysmenorrhea]] and [[hysterical]] conditions (i.e. pertaining to the womb), for raising [[blood pressure]] and increasing [[cardiac output]]. The activity of castoreum has been credited to the accumulation of [[salicin]] from [[willow]] trees in the beaver's diet, which is transformed to [[salicylic acid]] and has an action very similar to [[aspirin]].<ref>{{cite web|url=http://www.the-scientist.com/2005/03/28/S31/1/|title=The quest for pain relief: how much have we improved on the past?|author=Stephen Pincock|date=2005-03-28|accessdate=2007-06-17}}</ref> Castoreum continues to be used in [[perfume]] production.

==Beavers in culture==
{{Trivia|date=May 2008}}
[[Image:CDN-5-Cents-Szmurlo.jpg|thumb|A Beaver on the Canadian 5 Cent Coin (Nickel)]]

[[Image:Beaversnarnia.jpg|thumb|right|250px|Mrs and Mr Beaver in ''[[The Chronicles of Narnia: The Lion, the Witch and the Wardrobe]]''.]]

===Characters in media===
* Mr. and Mrs. Beaver are important heroic characters in the [[fantasy novel]] ''[[The Lion, the Witch and the Wardrobe]]''
* Beavers' habits, habitat and conservation status (as of 1908) are recurring themes in ''[[The Tent Dwellers]]'' by [[Albert Bigelow Paine]]
* [[Nickelodeon (TV channel)|Nickelodeon]] aired ''[[The Angry Beavers]]'', a children's television show
* [[Toothy]] and [[Handy]] from the Internet flash cartoon ''[[Happy Tree Friends]]''
* In the book ''[[After Man: A Zoology of the Future]]'' by [[Dougal Dixon]], the modern-day beaver still exists 50 million years from now. However, its back legs and tail have fused together to make one large paddle for better movement in water.
* In the "[[Cheese Shop sketch|Cheese Shop]]" sketch of ''[[Monty Python's Flying Circus]],'' a famished customer asks the proprietor of a cheese shop for any one of forty-two different kinds of cheese, including the nonexistent [[Venezuela]]n Beaver Cheese. Venezuela has no indigenous beavers.{{Fact|date=November 2007}}
*The ''[[Pokémon]]'' franchise features [[Bibarel]], who is based on a beaver.
*The Beaver Brothers are two characters from the video game [[The Legend of Zelda: Majora's Mask]]
* In the Playhouse Disney show , [[PB&J Otter]] , one of the characters named Munchy represents a beaver who always has quite the appetite on wood.

===Mascots, political and other===
* The importance of the American Beaver in the development of [[Canada]] through the [[fur trade]] led to its designation as the [[List of national animals|national animal]]. It is depicted on the [[Nickel (Canadian coin)|Canadian five-cent piece]] and was on the first [[postage stamp]] issued in the [[British North America|Canadian colonies]] in 1849 (the so-called "[[Postage stamps and postal history of Canada|Three-Penny Beaver]]"). As a [[national symbol]], the beaver was chosen to be the [[mascot]] of the [[1976 Summer Olympics]] held in [[Montreal]] with the name "Amik" ("beaver" in [[Anishinaabemowin]]). The beaver is also the symbol of many units and organizations within the [[Canadian Forces]], such as on the cap badges of the [[Royal 22e Régiment|Royal 22<sup>e</sup> Régiment]] and the [[Canadian Military Engineers]].
* [[Oregon]] is known as the "The Beaver State;" it is the state animal and appears on the state flag.
* Two [[Computer-generated imagery|CGI]]-generated beavers, named Frank and Gordon, are used in advertisements for [[Bell Canada]] in print, radio, and television.
* It is the [[List of U.S. state mammals|state mammal]] of [[New York]] (after the historical emblem of [[New Netherlands]]). It also appears on [[New York City]]'s [[coat of arms]], seal and flag.
* Because of its engineering capabilities, the beaver serves as the mascot of the [[Massachusetts Institute of Technology]], [[California Institute of Technology]], [[The City College of New York]], [[Oregon State University]], and the [[University of Toronto]]. It is also an emblem for [[London School of Economics]].

===Organizations===
* There is typically a Beaver Patrol in the [[Boy Scouts of America]]'s [[Wood Badge]] adult-leadership training program.{{Fact|date=November 2007}}
[[Image:Beaver-Szmurlo.jpg|thumb|An American Beaver in [[Calgary]], [[Alberta]]]]
* Canadian children between 5 and 7 can join "Beavers", the youngest organization in the Scouts Canada movement. During meetings, children gather at the "pond", which is the site of their "colony". Within the colony, the children are divided into "lodges".<ref>[http://www.scouts.ca/beavers.asp?cmPageID=250 scouts.ca]</ref>

===Miscellaneous===
* In the 17th century, based on a question raised by the [[Bishop]] of [[Quebec]], the [[Roman Catholic Church]] ruled that the beaver was a [[fish]] for purposes of dietary law. Therefore, the general prohibition on the consumption of [[meat]] on Fridays during [[Lent]] does not apply to beaver meat.<ref>http://www.chowdc.org/Papers/Saunders%202001.html</ref><ref>[http://www.jimmyakin.org/2005/02/lent_roundup.html JIMMY AKIN.ORG: Lenten Reader Roundup<!-- Bot generated title -->]</ref><ref>{{fr icon}}Lacoursière, Jacques. ''Une histoire du Québec'' ISBN 2-89448-050-4 Explains that Bishop François de Laval in the 17th century posed the question to the theologians of the [[Sorbonne]], who ruled in favour of this decision.</ref> The legal basis for the decision probably rests with the ''[[Summa Theologica]]'' of [[Thomas Aquinas]], which bases animal classification as much on habit as anatomy.<ref>[http://www.newadvent.org/summa/314708.htm ''The Summa Theologica of St. Thomas Aquinas''] II. 147:8 provides legal foundation upon which theologians argued in favour of beaver being like fish.</ref>
*In [[computability theory]], a [[Busy Beaver]] is a [[Turing machine]] which does as much work as possible given the size of its tape alphabet and underlying state machine.
* Someone with large frontal teeth (or 'buckteeth') can be referred to as a beaver.
* Beaver also represents [[vagina]] in [[sexual slang|slang]].<ref>{{cite web |url = http://www.news.com.au/dailytelegraph/story/0,22049,23358850-5006009,00.html| publisher = The Daily Telegraph|title = Kotex tampons' beaver advertisment denounced| date = 2008-03-11}} </ref>

<!--
==These images were in a section that got merged into another==
===They should be worked into the main article===

<s>[[Image:Beavertracks.JPG|center|thumb|150px|Beaver tracks in snow, in [[Ontario]]. Hind paws approx 20 cm long.]]</s>
[[Image:Beaver dam in Yellowstone.jpg|thumb|250px|[[Yellowstone National Park]].]]
<s>[[Image:Beaver dam in Tierra del Fuego.jpg|center|thumb|250px|[[Tierra del Fuego]]]]</s>
[[Image:Beaver dam in Fossil Butte NM-750px.JPG|thumb|250px|[[Fossil Butte National Monument]].]]
[[Image:BeaverDam 8409.jpg|center|thumb|300px|[[Lassen Volcanic National Park]].]]

{{Commons|Castor|Beaver}}
{{wikispecies|Castor}}
-->

==References==
{{reflist|2}}
*[http://www.itis.usda.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=180211 ITIS 180211] 2002-12-14

{{1911}}

== Further reading ==
*Rue, Leonard Lee, III.
**"The World of the Beaver", Lippincott Company, 1964.
**"Beavers", 2002. ISBN 0896585484

==External links==
{{Commons|Castor|Beaver}}
* [http://depts.washington.edu/natmap/facts/beaver_712.html Beaver Facts - NatureMapping Program]
* [http://www.BeaversWW.org Beavers: Wetlands & Wildlife website]
* [http://purl.galileo.usg.edu/ugafax/QL737xR6xD84 The Romance of the Beaver] - history of the beaver in the western hemisphere by A. Radclyffe Dugmore.
* [http://www.aigas.co.uk/2007-Beaver-Diary-g.asp Aigas Field Centre Beaver Project] - history of a pair of European beavers released into a large enclosure in the Highlands of Scotland.
* [http://fohn.net/beaver-pictures-facts/ Beaver Pictures & Facts]

[[Category:Beavers]]
[[Category:Fur trade]]
[[Category:Fauna of the Southeastern United States]]
[[Category:Mammals of Europe]]
[[Category:Mammals of the United States]]

{{Link FA|es}}

[[ar:قندس]]
[[bs:Dabar (životinja)]]
[[bg:Бобри]]
[[ca:Castor (animal)]]
[[cs:Bobr]]
[[cy:Afanc]]
[[da:Bæver]]
[[de:Biber]]
[[nv:Chaaʼ]]
[[et:Kobras]]
[[es:Castor]]
[[eo:Kastoro]]
[[fr:Castor (genre)]]
[[fy:Bevers]]
[[gd:Los-leathann]]
[[gl:Castor]]
[[ko:비버]]
[[hsb:Bobr]]
[[hr:Dabrovi]]
[[id:Berang-berang]]
[[it:Castor]]
[[he:בונה (בעל חיים)]]
[[lt:Bebriniai]]
[[nl:Bevers]]
[[cr:ᐊᒥᔅᒄ]]
[[ja:ビーバー]]
[[no:Bevere]]
[[nn:Bever]]
[[nrm:Bièvre]]
[[pl:Castor]]
[[pt:Castor]]
[[ro:Castor (animal)]]
[[ru:Бобровые]]
[[simple:Beaver]]
[[fi:Majavat]]
[[sv:Bävrar]]
[[ta:பீவர்]]
[[chr:ᏙᏯ]]
[[tr:Kunduz]]
[[uk:Бобер]]
[[zh:河狸]]

Revision as of 04:03, 10 May 2008

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MMM DEREK

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