Bear
From Wikipedia, the free encyclopedia
[Photo] A Syrian Brown Bear (Ursus arctos syriacus) in the biblical zoo in Jerusalem. Date 13 June 2006. Photo by Amoruso
Bears (family Ursidae) are large mammals in the order Carnivora. Bears are classified as caniforms, or doglike carnivorans, with the pinnipeds being their closest living relatives. Although there are only eight living species of bear, they are widespread, appearing in a wide variety of habitats throughout the Northern Hemisphere and partially in the Southern Hemisphere.
Common characteristics of modern bears include a large body with stocky legs, a long snout, shaggy hair, paws with five nonretractile claws, and a short tail. While the polar bear is mostly carnivorous and the giant panda feeds almost entirely on bamboo, the remaining six species are omnivorous, with largely varied diets including both plants and animals.
With the exceptions of courting individuals and mothers with their young, bears are typically solitary animals. They are sometimes diurnal, but are usually active during the night (nocturnal) or twilight (crepuscular). Bears are aided by an excellent sense of smell, and despite their heavy build and awkward gait, they can run quickly and be adept climbers and swimmers. Bears use shelters such as caves and burrows as their dens, which are occupied by most species during the winter for a long period of sleep similar to hibernation.
Bears have been hunted since prehistoric times for their meat and fur. To this day, they play a prominent role in the arts, mythology, and other cultural aspects of various human societies. In modern times, bears have been exploited through the encroachment of their habitats and the illegal trade of bears and bear parts, including the Asian bile bear market. The IUCN lists six bear species as vulnerable or endangered, and even "least concern" species such as the brown bear are at risk of extirpation in certain countries. The poaching and international trade of these most threatened populations is prohibited, but still ongoing.
Etymology
Modern English "bear" derives from Old English "bera", which itself derives from Proto-Germanic "*beron" meaning "the brown one". (Compare Scandinavian "bj??rn", Dutch "beer", Standard German "B??r" all meaning "bear").
Both Greek ("arktos") and Latin ("ursus") have retained the Proto-Indo-European root word for "bear" ("*rtko") but it was ritually replaced in the northern branches of the Indo-European languages (The Germanic, Baltic, Celtic and Slavic branches) because of the hunters' taboo on the names of wild animals. For example the Irish word for "bear" translated means "the good calf", in Welsh it translates as "honey-pig", in Lithuanian it means "the licker" and Russian "медведь" literally means "honey-eater". In Sanskrit the bear is called rkshas.
In English, the adjective "ursine" is used to describe things of a bear-like nature, while the collective noun for a group of them is a sleuth.
Physical attributes
Common characteristics of bears include a short tail, acute senses of smell and hearing, a snubbed nose, five non-retractable claws per paw, and long, dense, shaggy fur.
Bears have large bodies and powerful limbs. They are capable of standing up on their hind legs. They have broad paws, long snouts, and round ears. Their teeth are bared for defense and used as tools, depending on the diet of the bear. Their claws are used for ripping, digging, and catching. Bears are generally more robust and stockier than other land carnivorans.
Polar bears are the longest type, and in fact one of the largest extant carnivores, though brown bears are the heaviest. Sun bears are the smallest, only the size of a large dog.
Habitats
Bears live in a variety of habitats from the tropics to the Arctic and from forests to snowfields. They are mainly omnivorous, although some have a more specialized diet, such as polar bears who mainly consume fish and marine mammalia. They eat lichens, roots, nuts, and berries. They can also go to a river or other body of water to capture fish. Bears will commonly travel far for food. Hunting times are usually in the dusk or the dawn except when humans are nearby.
Behavior
Some of the larger species, such as the polar bear and the grizzly bear, are dangerous to humans, especially in areas where they have become used to people. For the most part, bears are shy and are easily frightened of humans. They will, however, defend their cubs ferociously if a situation calls for it.
Reproductive behavior
The bear's courtship period is very brief. Bears reproduce seasonally, usually after a period of inactivity similar to hibernation. Cubs are born toothless, blind, and bald. The cubs of brown bears, usually born in litters of 1???3, will typically stay with the mother for two full seasons. They feed on their mother's milk through the duration of their relationship with their mother, although as the cubs continue to grow, nursing becomes less frequent and learn to begin hunting with the mother. They will remain with the mother for approximately three years, until she enters the next cycle of estrus and drives the cubs off. Bears will reach sexual maturity in five to seven years. Bears are generally solitary creatures and will not stay close together for long periods of time. Exceptions have been regularly observed; siblings recently on their own and sub-adult bears of similar age and status will spend a significant amount of time in informal social groups.
Other
Many bears of northern regions are assumed to hibernate in the winter. While many bear species do go into a physiological state called hibernation or winter sleep, it is not true hibernation. In true hibernators, body temperatures drop to near ambient and heart rate slows drastically, but the animals periodically rouse themselves to urinate or defecate and to eat from stored food. The body temperature of bears, on the other hand, drops only a few degrees from normal and heart rate slows only slightly. They normally do not wake during this "hibernation", and therefore do not eat, drink, urinate or defecate the entire period. Higher body heat and being easily roused may be adaptations, because females give birth to their cubs during this winter sleep. It can therefore be considered a more efficient form of hibernation because they need not awake through the entire period, but they are more quickly and easily awakened at the end of their hibernation.
Laws have been passed in many areas of the world to protect bears from hunters or habitat destruction. Bears in captivity have been forced to be trained to dance, box, or ride bicycles; however, this use of the animals became controversial in the late 20th century. In cartoons, circus bears are frequently depicted riding unicycles.
The brown bear is Finland's national animal. In the United States, the black bear is the state animal of Louisiana, New Mexico, and West Virginia; the grizzly bear is the state animal of both Montana and California.
The constellations Ursa Major and Ursa Minor represent bears.
Bears as food and medicine
Many people enjoy hunting bears and eating them. Their meat is dark and stringy, like a tough cut of beef. In Cantonese cuisine, bear paws are considered a delicacy. The peoples of China, Japan, and Korea use bears' body parts and secretions (notably their gallbladders and bile) as part of traditional Chinese medicine. It is believed more than 12,000 bile bears are kept on farms, farmed for their bile, in China, Vietnam and South Korea.
Classification
Family Ursidae
Subfamily Ailuropodinae
Giant Panda, Ailuropoda melanoleuca
Dwarf Panda, Ailuropoda minor (extinct)
Subfamily Agriotherinae
Agriotherium (extinct)
Agriotherium inexpectans (extinct)
Agriotherium sivalensis (extinct)
Agriotherium roblesi (extinct)
Agriotherium africanum (extinct)
Subfamily Tremarctinae
Spectacled Bear, Tremarctos ornatus
Florida Cave Bear, Tremarctos floridanus (extinct)
Giant Short-Faced Bear, Arctodus simus (extinct)
Short-Faced Bear, Arctodus pristinus (extinct)
Brazilian Short-Faced Bear, Arctotherium brasilense (extinct)
Argentine Short-Faced Bear, Arctotherium latidens (extinct)
Subfamily Ursinae
Brown Bear, Ursus (Ursus) arctos
Subspecies Syrian (Brown) Bear Ursus arctos syriacus
Subspecies Grizzly Bear, Ursus arctos horribilis
Subspecies Kodiak Bear, Ursus arctos middendorffi
Subspecies Himalayan Brown Bear, Ursus arctos isabellinus
Subspecies Bergman's Bear, Ursus arctos piscator (extinct?)
Atlas Bear, Ursus arctos crowtheri (extinct)
American Black Bear, Ursus (Ursus) americanus
Subspecies Cinnamon Bear, Ursus americanus cinnamomum
Subspecies Kermode Bear, Ursus americanus kermodie
Polar Bear, Ursus (Thalarctos) maritimus
Asiatic Black Bear, Ursus (Selenarctos) thibetanus
Formosan Black Bear, Ursus thibetanus formosanus
Ursus thibetanus gedrosianus
Ursus thibetanus japonica
Ursus thibetanus laniger
Ursus thibetanus mupinensis
Ursus thibetanus thibetanus
Ursus thibetanus ussuricu
Sloth Bear, Melursus ursinus
Subspecies Sri Lankan Sloth Bear Melursus ursinus inornatus
Subspecies Indian Sloth Bear Melursus ursinus ursinus
Sun Bear, Helarctos malayanus
Subspecies Borneo Sun Bear Helarctos malayanus euryspilus
Auvergne Bear, Ursus minimus (extinct)
Etruscan Bear, Ursus etruscus (extinct)
European Cave Bear, Ursus spelaeus (extinct)
MacFarlane's Bear, Ursus (Vetularctos) inopinatus (cryptid; if a good species, extinct)
The genera Melursus and Helarctos are sometimes also included in Ursus. The Asiatic black bear and the polar bear used to be placed in their own genera, Selenarctos and Thalarctos which are now placed at subgenus rank.
A number of hybrids have been bred between American black, brown, and polar bears.
...
http://en.wikipedia.org/wiki/Bear
| The text in this page is based on the copyrighted Wikipedia article shown in above URL. It is used under the GNU Free Documentation License. You may redistribute it, verbatim or modified, providing that you comply with the terms of the GFDL. |
|
