Bear
2007 Schools Wikipedia Selection. Related subjects: Mammals
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A bear is a large mammal in the family Ursidae of the order Carnivora. The adjective "ursine" is used to describe things of a bear-like nature. The collective noun for a group of them is a sleuth.
Etymology
Modern English "bear" derives from Old English "bera", which itself derives from Proto-Germanic "*beron" meaning "the brown one". (Compare Old Norse "björn", Dutch "beer" and German "Bär" 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 "one who leads to honey".
Physical attributes
Common characteristics of bears include a short tail, acute senses of smell and hearing, 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. Black bears, and likely other bears, have colour vision to help them identify fruits and nuts.
Depending on the species, bears can have 32 to 42 teeth. Bear teeth are not specialized for killing their prey like those of cats. Normal canine teeth in a carnivore are generally large and pointed used for killing prey, while bears' canine teeth are relatively small and typically used in defense or as tools. Bears' molar teeth are broad, flat and are used to shred and grind plant food into small digestible pieces.
Bears have four limbs that end in paws. Each paw has five long, sharp claws that are unretractible, unlike cats. These claws can be used to climb trees, rip open termite nests and beehives, dig up roots, or catch prey, depending on the species. While most carnivores tend to walk on their toes in a way that is adapted for speed, bears have a plantigrade stance. They walk with their weight on the soles of their feet, with the heel touching the ground, while the claws of the arm are used more for balance. Although slower than most carnivores, a running bear can reach speeds of up to 50 km/h (30 mph).
A bear's fur is often long and shaggy. Fur colour varies among species, ranging from white, blonde or cream, black and white, to all black or all brown. Colors of a bear's fur can also vary within species. For example, American black bears may be black, brown, reddish-brown, or bluish-black. Several species, such as the sun bear and spectacled bear have a light-colored chest with facial markings.
In all bear species, males are larger than females, but the difference between sexes varies and is greatest in the largest species. Large male polar bears may weigh twice as much as females, while smaller male and female bears are much more similar in weight. A bear's life span seems to last about 25 to 40 years. Bears living in the wild tend to die younger than their zoo-counterparts.
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 specialised diet, such as polar bears. 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.
Behaviour
Bears generally lead solitary lives, except for mothers attending her cubs, or males and females during mating season. Bears form temporary groups only when food is plentiful in a small area. Alaskan brown bears group in the same area to feed on salmon during the annual salmon runs, when the fish swim upriver to reach their spawning grounds. Other bears may live alone but exist in a social network. A male and female may live in an overlapping home range, each defending their range from other bears of the same sex. Male young usually leave their mothers to live in other areas, but females often live in an area that overlaps that of their mother.
Bears travel over large territories in search of food, remembering the details of the landscape they cover. They use their excellent memories to return to locations where food was plentiful in past years or seasons. Most bears are able to climb trees to chase prey or gain access to additional vegetation. The only exceptions are polar bears and large adult brown bears, whose heavy weight makes it difficult to climb trees.
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 behaviour
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. Exception have been regularly observed; siblings recently on their own, and subadult bears of similar age and status will oftentimes spend significant amounts of time in informal social groups.
Bear/human interaction
Despite their large size, bears, like many other forest animals, are adept at moving through wooded or rugged terrain while barely making any noise. They will also exist in surprisingly close proximity with humans.
Bears will generally avoid contact with humans, and are usually aware of a human's presence long before the human is aware of the bear. As a result, encounters are typically avoidable and rare. However, bears are opportunistic feeders, and will generally take food where it is available. When humans provide feeding opportunities, such as left out garbage, food stored outside, or deliberate feeding, the chance of confrontation escalates. As a bear begins to associate human presence with food, it may lose its shyness and the hazard it poses to humans will become unbearable. Conflicts may also arise in situations where the bear regards a human as an immediate threat to itself, its cubs, or food cache (which is one reason that found animal carcasses should be avoided). In a chance encounter with a bear, the best course of action is usually to back away slowly in the direction that you came, speaking in a loud, calm tone to make sure the bear is aware of your presence and will not be caught off guard. The bear will rarely become aggressive and bear towards you. In order to protect yourself, some suggest passively lying on the ground and waiting for the bear to lose interest. Another approach is to constantly maintain an obstacle between you and the bear, such as a thick tree or boulder. A person is much more agile and quick than a bear allowing him or her to respond to a bear's clockwise or counter-clockwise movement around the obstacle and move accordingly. The bear's frustration will eventually cause disinterest. One can then move away from the bear to a new obstacle and continue this until he or she has created a safe distance from the bear. When encountering a bear, one should never look directly into the bear's eyes. This action can be misconstrued by many wild animals as an aggressive act.
Other
Many bears of northern regions are assumed to hibernate in the winter. In medieval times it was believed that they died and were reborn in the spring. 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 do not wake normally 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 bear cubs during this winter sleep.
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.
Kodiak bears are the largest type, and in fact one of the largest extant carnivores, though polar bears are the heaviest. Sun bears are the smallest, only the size of a large dog. 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. Thousands of bile bears are farmed for their bile in China, Vietnam, and Korea.
Classification
- Family Ursidae
- Subfamily Ailuropodinae
- Giant Panda, Ailuropoda melanoleuca
- Dwarf Panda, Ailuropoda minor (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 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)
- MacFarlane's Bear, Ursus inopinatus (extinct)
- American Black Bear, Ursus americanus
- Subspecies Kermode Bear, Ursus americanus kermodie
- Polar Bear, Ursus maritimus
- Asiatic Black Bear, Ursus thibetanus, or Selenarctos tibetanus
- Ursus thibetanus formosanus, or Selenarctos tibetanus formosanus
- Ursus thibetanus gedrosianus, or Selenarctos tibetanus gedrosianus
- Ursus thibetanus japonica, or Selenarctos tibetanus japonica
- Ursus thibetanus laniger, or Selenarctos tibetanus laniger
- Ursus thibetanus mupinensis, or Selenarctos tibetanus mupinensis
- Ursus thibetanus thibetanus, or Selenarctos tibetanus thibetanus
- Ursus thibetanus ussuricu, or Selenarctos tibetanus ussuricu
- Asiatic black bears might be classified as genus Selenarctos.
- Auvergne Bear, Ursus minimus (extinct)
- Etruscan Bear, Ursus etruscus (extinct)
- European Cave Bear, Ursus spelaeus (extinct)
- Atlas Bear, Ursus crowtheri (extinct)
- Sloth Bear, Melursus (Ursus) ursinus
- Subspecies Sri Lankan Sloth Bear Melursus (Ursus) ursinus inornatus
- Subspecies Indian Sloth Bear Melursus (Ursus) ursinus ursinus
- Sun Bear, Helarctos malayanus
- Subspecies Borneo Sun Bear Helarctos (Ursus) malayanus euryspilus
- Brown Bear, Ursus arctos
- Subfamily Ailuropodinae
The genera Melursus and Helarctos are included in the genus Ursus. The Asiatic Black Bear and the Polar Bear used to be placed in their own genera, Selenarctos and Thalarctos.
A number of hybrids have been bred between American Black, Brown and Polar Bears (see Ursinae hybrids).
Evolutionary relationships
Bears are members of the order Carnivora, suborder Caniformia, and family Ursidae. Other members of the Caniformia include wolves and other dog-like mammals (family Canidae), weasels, badgers and allies (family Mustelidae), raccoons (family Procyonidae), and walruses (family Odobenidae), seals (family Phocidae), and sea lions (family Otariidae). Although bears are often described as having evolved from a dog-like ancestor, their closest living relatives are the pinnipeds (walruses, seals, and sea lions).
The origins of the bears can be traced back to the raccoon-sized, dog-like Cephalogale from the middle Oligocene and early Miocene (approximately 20-30 million years ago) of Europe. Cephalogale gave rise to a lineage of early bears, the genus Ursavus. This genus radiated in Asia and ultimately gave rise to the first true bears (genus Ursus) in Europe, 5 million years ago. Extinct bear genera include Arctodus, Agriarctos, Agriotherium, Plionarctos and Indarctos.
Although there has previously been much discussion as to whether the Giant Panda belongs to the bear family or the raccoon family, recent DNA analyses have shown that the Giant Panda is a member of the Family Ursidae and as such is more closely related to other bears. The status of the Red Panda remains uncertain, but many experts, including Wilson and Reeder, classify it as a member of the bear family. Others place it with the racoons in Procyonidae or in its own family, the Ailuridae. The many similarities between the two pandas are thought to represent convergent evolution for feeding primarily on bamboo.
There is also evidence that, unlike their neighbors elsewhere, the Brown Bears of Alaska's ABC islands are more closely related to Polar Bears than they are to other Brown Bears in the world. Researchers Gerald Shields and Sandra Talbot of the University of Alaska Fairbanks Institute of Arctic Biology studied the DNA of several samples of the species and found that their DNA is different from that of other Brown Bears. The researchers discovered that their DNA was unique compared to Brown Bears anywhere else in the world. The discovery has shown that while all other Brown Bears share a Brown Bear as their closest relative, those of Alaska's ABC Islands differ and share their closest relation with the Polar Bear. There is also supposed to be a very rare large bear in China called the Blue Bear, which presumably is a type of black bear. This animal has never been photographed.
Bears in mythology
Some evidence has been brought to bear of prehistoric bear worship, see Arctic, Arcturus, Great Bear, Berserker, Kalevala. Anthropologists such as Joseph Campbell have regarded this as a common feature in most of the fishing and hunting-tribes. The prehistoric Finns, along with most Finno-Ugric peoples, considered the bear as the spirit of one's forefathers. This is why the bear was a greatly respected animal, with several euphemistic names. There has been evidence about early bear worship in China and among the Ainu culture as well. In the Korean mythology, Korean people identifies bear as their ancestor and symbolic animal; also several other Tungusic people consider bear as their ancestor animal.
In addition, the Proto-Indo-European word for bear, *hr̥ktos (ancestral to the Greek arktos, Latin ursus, Welsh arth (c.f. Arthur), Sanskrit *ṛkṣa, Hittite hartagga) seems to have been subject to taboo deformation or replacement (as was the word for wolf, wlkwos), resulting in the use of numerous unrelated words with meanings like "brown one" (English bruin) and "honey-eater" (Slavic medved). Thus four separate Indo-European language groups do not share the same PIE root. In the Finnish countryside, the word for "bear" remains taboo to this day. The theory of the bear taboo is taught to almost all beginning students of Indo-European and historical linguistics; the putative original PIE word for bear is itself descriptive, because a cognate word in Sanskrit is rakshas, meaning "harm, injury" .
Bears as symbols and totems
Numerous cities around the world have adopted the bear as a symbol, notably the Swiss capital Bern, which takes its name from the German for bear, bär. The bear is also the name-emblem of Berlin bärlein meaning small bear. Bears are a common symbol of heraldry (e.g. Rawa Coat of Arms, Bernhardt coat of arms). In the arms of the bishopric of Freising (illustration, right) the bear is the dangerous totem animal tamed by Saint Corbinian and made to carry his civilized baggage over the mountains: the allegory of the civilizing influence of Christianity is inescapable. A bear also features prominently in the legend of Saint Romedius, who is also said to have tamed one of these animals and had the same bear carry him from his hermitage in the mountains to the city of Trento.
The bear is a common national symbol for Russia (as well as the Soviet Union) and even Germany. It was used in the Ronald Reagan political ad "Bear in the woods." A subspecies of Grizzly Bear is featured on the Flag of California, first flown in 1846 during the Bear Flag Revolt. Also, the bear, the bruin, or specific types of bears are popular nicknames or mascots, e.g. for sports teams (Chicago Bears,Boston Bruins); and a bear cub was mascot of the 1980 Summer Olympics.
Bears in figures of speech
The physical attributes and behaviors of bears are commonly used in figures of speech in English. In the stock market, a bear market is a period of declining prices. Pessimistic forecasting or negative activity is said to be bearish (due to the stereotypical posture of bears looking downwards), and one who expresses bearish sentiment is a bear. Its opposite is a bull market, and bullish sentiment from bulls. In CB slang, "bear" (or "smokey", in reference to Smokey Bear) is a nickname for highway patrol. In gay slang, the term " bear" refers to male individuals who possess physical attributes much like a bear, such as a heavy build, abundant body hair, and commonly facial hair. To "try like a bear" means to try your hardest to catch the attention of a certain lady. The harder you try, the better the bear you are. A bear hug is typically a tight hug that involves wrapping one's arms around another person, often leaving that person's arms immobile. The Chicago Bears, a United States football team, are often referred to as "The Monsters of the Midway," a term that alludes to imagery of bears as monsters, or frightening creatures.