Elk

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The elk or wapiti (Cervus canadensis) is one of the largest species  of  deer  in the world and one of the largest land  mammals  in  North America  and  eastern Asia. In the deer family (Cervidae), only the larger moose  (Alces alces), which is called an "elk" in  Europe, and the  sambar  (Rusa unicolor) rival the elk in size. Elk are similar to the Red Deer  (Cervus elaphus) found in Europe, of which they were long believed to be a  subspecies. However, evidence from a 2004 study of the mitochondrial DNA  indicates they are a distinct  species.

Elk range in forest and forest-edge habitat, feeding on grasses, plants, leaves, and bark. Although native to North America and Eastern Asia, they have adapted well to countries where they have been introduced, including Argentina,  Australia , and  New Zealand. Their great adaptability may threaten endemic  species and ecosystems into which they have been introduced.

Male elk have large antlers  which are shed each year. Males also engage in ritualized mating behaviors during the rut, including posturing, antler wrestling (sparring), and bugling, a loud series of vocalizations which establishes dominance over other males and attracts females.

Elk are susceptible to a number of infectious diseases, some of which can be transmitted to livestock. Efforts to eliminate infectious diseases from elk populations, largely through vaccination, have had mixed success.

Some cultures revere the elk as a spiritual force. In parts of Asia, antlers and their velvet  are used in  traditional medicines. Elk are hunted as a game species; the meat is leaner and higher in protein  than  beef  or  chicken .| [2]

Naming and etymologyEarly European explorers in North America, who were familiar with the smaller red deer  of Europe, thought that the larger North American animal looked like a  moose, causing the usage of the common European name for moose, which is elk. The name elk is connected with the Latin  alces, and with  Old Norse  elgr,  Scandinavian  elg/älg, and  German  Elch, all of which refer to the animal known in North America as the moose.| [3]

The name wapiti is from the Shawnee  and  Cree  word waapiti, meaning white rump.| [4]  The elk is also referred to as the maral in Asia, though this is due to confusion with the  East European red deer  (Cervus elaphus maral), which is a subspecies of European red deer. There is a subspecies of elk in Mongolia  called the Altai maral (Cervus canadensis sibiricus)| [5] , which is also known by names such as Altai wapiti, Siberian wapiti, and/or Siberian elk[ citation needed ]. The name "Siberian elk" in this sense is misleading, as in Eurasia the name "elk" is used in relation to ''Alces alces ssp. cameloides, alternatively classified as Alces americanus.| [6] That is why all the Asian subspecies of Cervus canadensis'' are named "wapiti":  Altai Wapiti,  Tian Shan Wapiti ,  Manchurian wapiti , and  Alashan wapiti.

edit ] Taxonomy
EnlargeElk at the Opal terrace at Mammoth Hot Springs, Yellowstone National Park Members of the  genus   Cervus  (and hence early relatives or possible ancestors of the elk) first appear in the  fossil  record 25 million years ago, during the  Oligocene  in  Eurasia, but do not appear in the North American fossil record until the early  Miocene .| [7]  The extinct  Irish Elk  (Megaloceros) was not a member of the genus Cervus, but rather the largest member of the wider deer family (Cervidae) known from the fossil record.| [8]

Until recently, red deer and elk were considered to be one species, Cervus elaphus.| [5] | [9]  However, mitochondrial DNA studies, conducted on hundreds of samples in 2004 from red deer and elk subspecies as well as other species of the Cervus deer family, strongly indicate that elk, or wapiti, should be a distinct species, namely Cervus canadensis.| [10]  The previous classification had over a dozen subspecies under the C. elaphus species designation; DNA evidence concludes that elk are more closely related to  Thorold's deer  and even  sika deer  than they are to the red deer.| [10]  Though elk and red deer can produce fertile offspring in captivity, geographic isolation between the species in the wild and differences in mating behaviors indicate that reproduction between them outside a controlled environment would be unlikely. However, the two species have freely inter-bred in New Zealand's Fiordland National Park, where the cross-bred animals have all but removed the pure elk blood from the area.| [11]

edit ] Subspecies
Enlarge Audubon 's " Eastern Elk " which is now extinctThere are numerous subspecies  of elk described, with six from North America and four from Asia, although some  taxonomists  consider them different  ecotypes  or  races  of the same species (adapted to local environments through minor changes in appearance and behavior). Populations vary as to antler shape and size, body size, coloration and mating behavior. DNA investigations of the Eurasian subspecies revealed that  phenotypic  variation in antlers, mane and rump patch development are based on "climatic-related lifestyle factors".| [12]  Of the six subspecies of elk known to have inhabited North America in historical times, four remain, including the  Roosevelt  (C. canadensis roosevelti),  Tule  (C. canadensis nannodes),  Manitoban  (C. canadensis manitobensis) and  Rocky Mountain  (C. canadensis nelsoni).| [13]  The  Eastern elk  (C. canadensis canadensis) and  Merriam's Elk  (C. canadensis merriami) subspecies have been extinct for at least a century.| [14]  <sup class="reference" id="cite_ref-Allen_14-0">| [15] |   Male tule elk in Point ReyesFour subspecies described in Asia include the  Altai Wapiti  (C. canadensis sibiricus) and the  Tianshan Wapiti  (C. canadensis songaricus). Two distinct subspecies found in China  and  Korea  are the  Manchurian wapiti  (C. canadensis xanthopygus) and the  Alashan wapitis  (C. canadensis alashanicus). The Manchurian wapiti is darker and more reddish in coloration than the other populations. The Alashan wapiti of north central China is the smallest of all subspecies, has the lightest coloration and is the least studied.<sup class="reference" id="cite_ref-Geist_10-1">| [11] Biologist Valerius Geist, who has written on the world's various deer species, holds that there are only three subspecies of elk. Geist recognizes the Manchurian and Alashan wapiti but places all other elk into C. canadensis canadensis, claiming that classification of the four surviving North American groups as subspecies is driven, at least partly, for political purposes to secure individualized conservation and protective measures for each of the surviving populations.<sup class="reference" id="cite_ref-Geist2_15-0">| [16]

Recent DNA studies suggest that there are no more than three or four subspecies of Wapiti. All American forms seem to belong to one subspecies (Cervus canadensis canadensis). Even the Siberian elk (Cervus canadensis sibiricus) are more or less identical to the American forms and therefore may belong to this subspecies, too. However the Manchurian wapiti  (Cervus canadensis xanthopygus) is clearly distinct from the Siberian forms, but not distinguishable from the Alashan Wapiti. The Chinese forms MacNeill's Deer,  Kansu red deer , and  Tibetan red deer  belong also to the Wapitis and were not distinguishable from each other by mitochondrial DNA studies.<sup class="reference" id="cite_ref-Ludt_9-2">| [10]  These Chinese subspecies are sometimes treated as a distinct species, the  Central Asian Red Deer  (Cervus wallichi), which also includes the  Kashmir stag .<sup class="reference" id="cite_ref-Mattioli.2C_2011_16-0">| [17] |    Altai Wapiti  (C. c. sibiricus)Enlarge Manchurian Wapiti  (C. c. xanthopygus)*Northern and American Group
 * Roosevelt Elk (C. c. roosevelti)
 * Tule Elk (C. canadensis nannodes)
 * Manitoban Elk (C. c. manitobensis)
 * Rocky Mountain Elk (C. c. nelsoni)
 * Eastern elk (C. c. canadensis; extinct)
 * Merriam's Elk (C. c. merriami; extinct)
 * Altai Wapiti (C. c. sibiricus)
 * Tianshan Wapiti (C. c. songaricus)
 * Eastern group
 * Manchurian Wapiti (C. c. xanthopygus)
 * Alashan Wapiti (C. c. alashanicus)
 * Southern Group ( Central Asian Red Deer )
 * MacNeill's Deer (C. c. macneilli)
 * Kansu Red Deer (C. c. kansuensis)
 * Tibetan Red Deer (C. c. wallichii)
 * Kashmir Stag (C. c. hanglu)

edit ] Anatomy
EnlargeA herd of Roosevelt Elk in Redwood National and State Parks,  California The elk is a large animal of the  artiodactyle   ungulate  order, possessing an even number of toes on each foot, similar to those of  camels ,  goats  and  cattle. It is a ruminant  species, with a four-chambered stomach, and feeds on grasses, plants, leaves and bark. During the summer, elk eat almost constantly, consuming between 4 and 7 kilograms (8.8 and 15 lb) daily.<sup class="reference" id="cite_ref-food_17-0">| [18] In North America, males are called bulls, and females are called cows. In Asia, stag and hind, respectively, are sometimes used instead.

Elk are more than twice as heavy as mule deer  and have a more reddish hue to their hair coloring, as well as large, buff colored rump patches and smaller tails. Moose are larger and darker than elk; bulls have distinctively different antlers. Elk gather in herds, while moose are solitary. Elk cows average 225 kilograms (500 lb), stand 1.3 metres (4.3 ft) at the shoulder, and are 2 metres (6.6 ft) from nose to tail. Bulls are some 40% larger than cows at maturity, weighing an average of 320 kilograms (710 lb), standing 1.5 metres (4.9 ft) at the shoulder and averaging 2.5 metres (8.2 ft) in length.<sup class="reference" id="cite_ref-facts_18-0">| [19] The largest of the subspecies is the Roosevelt elk, found west of the  Cascade Range  in the  U.S. states  of  California,  Oregon  and  Washington , and in the  Canadian  province of  British Columbia. Roosevelt elk have been reintroduced into Alaska, where the largest males are estimated to weigh up to 600 kilograms (1,300 lb).<sup class="reference" id="cite_ref-Eide_19-0">| [20] |   Rocky Mountain elk in  Yellowstone National Park Only the males have antlers, which start growing in the spring and are shed each winter. The largest antlers may be 1.2 metres (3.9 ft) long and weigh 18 kilograms (40 lb).<sup class="reference" id="cite_ref-rmef2_20-0">| [21] Antlers are made of bone which can grow at a rate of 2.5 centimetres (0.98 in) per day. While actively growing, the antlers are covered with and protected by a soft layer of highly vascularised skin known as velvet. The velvet is shed in the summer when the antlers have fully developed. Bull elk may have eight or more tines on each antler; however, the number of tines has little to do with the age or maturity of a particular animal. The Siberian and North American elk carry the largest antlers while the Altai wapiti have the smallest.<sup class="reference" id="cite_ref-Geist_10-2">| [11] The formation and retention of antlers is  testosterone -driven.<sup class="reference" id="cite_ref-nwr_21-0">| [22]  After the breeding season in late fall, the level of  pheromones  released during  estrus  declines in the environment and the testosterone levels of males drop as a consequence. This drop in testosterone leads to the shedding of antlers, usually in the early winter.

During the fall, elk grow a thicker coat of hair, which helps to insulate them during the winter. Males, females and calves of Siberian and North American elk all grow thin neck manes; female and young Manchurian and Alashan wapitis do not.<sup class="reference" id="cite_ref-Geist2_15-1">| [16] By early summer, the heavy winter coat has been shed, and elk are known to rub against trees and other objects to help remove hair from their bodies. All elk have small and clearly defined rump patches with short tails. They have different coloration based on the seasons and types of habitats, with gray or lighter coloration prevalent in the winter and a more reddish, darker coat in the summer. Subspecies living in arid climates tend to have lighter colored coats than do those living in forests.<sup class="reference" id="cite_ref-Pisarowicz_22-0">| [23] Most have lighter yellow-brown to orange-brown coats in contrast to dark brown hair on the head, neck, and legs during the summer. Forest-adapted Manchurian and Alashan wapitis have darker reddish-brown coats with less contrast between the body coat and the rest of the body during the summer months.<sup class="reference" id="cite_ref-Geist_10-3">| [11] Calves are born spotted, as is common with many deer species, and they lose their spots by the end of summer. Adult Manchurian wapiti may retain a few orange spots on the back of their summer coats until they are older. This characteristic has also been observed in the forest-adapted European red deer.<sup class="reference" id="cite_ref-Geist_10-4">| [11] &nbsp