Bear

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Bear
Fossil range: 38–0 Ma
Late Eocene - Recent
Bear species, as illustrated in the Cyclopeadia of the natural sciences
Bear species, as illustrated in the Cyclopeadia of the natural sciences
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Suborder: Caniformia
Superfamily: Ursoidea
Family: Ursidae
G. Fischer de Waldheim, 1817
Genera

Bears are mammals of the family Ursidae. 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. That which pertains to bears is called ursine. Bears are found in the continents of North America, South America, Europe, and Asia.

Common characteristics of modern bears include a large body with stocky legs, a long snout, shaggy hair, plantigrade 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 are adept climbers and swimmers. In autumn some bear species forage large amounts of fermented fruits which affects their behaviour.[1] 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, the bear's existence has been pressured 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.

Contents

Evolutionary relationships

Fossil of Cave bear (Ursus spelaeus)

The Ursidae family belongs to the order Carnivora and is one of nine families in the suborder Caniformia, or "doglike" carnivorans. Bears' closest living relatives are the pinnipeds, a clade of three families: Odobenidae (the walrus), Otariidae (fur seals and sea lions), and Phocidae (true or earless seals). Bears comprise eight species in three subfamilies: Ailuropodinae (monotypic with the giant panda), Tremarctinae (monotypic with the Spectacled Bear), and Ursinae (containing six species divided into one to three genera, depending upon authority).

Unlike other carnivora, bears have plantigrade hind feet

The origins of Ursidae can be traced back to the very small and graceful Parictis that had a skull only 7 cm (3 in) long. Parictis first occur in North America in the Late Eocene (ca. 38 million years ago), but this genus did not appear in Eurasia and Africa until the Miocene.[2] The raccoon-sized, dog-like Cephalogale, however, is widely regarded as the most primitive ursid and is ideally suited as a representative basal taxon for the family. Cephalogale first appeared during the middle Oligocene and early Miocene (approximately 20–30 million years ago) in Europe. Cephalogale gave rise to a lineage of early bears of 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. Even among its primitive species, such as C. minor, it exhibits typical ursid synapomorphic dentition such as posteriorly oriented M2 postprotocrista molars, elongated m2 molars, and a reduction of the premolars. Living members of the ursids are morphologically well defined by their hypocarnivorous (non-strictly meat-eating) dentitions, but fossil ursids include hypercarnivorous (strictly meat-eating) taxa, although they never achieved the extreme hypercarnivory seen in mustelids. Cephalogale was a mesocarnivore (intermediate meat-eater).[3] Other extinct bear genera include Arctodus, Agriarctos, Plionarctos and Indarctos.

It is uncertain whether ursids were in Asia during the late Eocene, although there is some suggestion that a limited immigration from Asia may have produced Parictis in North America due to the major sea level lowstand at ca. 37 Ma, but no Parictis fossils have yet to be found in East Asia. Ursids did, however, become very diversified in Asia later during the Oligocene. Four genera representing two subfamilies (Amphicynodontinae and Hemicyoninae) have been discovered in the Oligocene of Asia: Amphicticeps, Amphicynodon, Pachycynodon, and Cephalogale. Amphicticeps is endemic from Asia and the other three genera are common to both Asia and Europe. This indicates migration of ursids between Asia and Europe during the Oligocene and migration of several taxa from Asia to North America likely occurred later during the late Oligocene or early Miocene. Although Amphicticeps is morphologically closely related to Allocyon, and also to Kolponomos of North America, no single genus of the Ursidae from this time period is known to be common to both Eurasia and North America. Cephalogale, however, do appear in North America in the early Miocene. It is interesting to note that rodents, such as Haplomys and Pseudotheridomys (late Oligocene) and Plesiosminthus and Palaeocastor (early Miocene), are common to both Asia and North America and this indicates that faunal exchange did occur between Asia and North America during the late Oligocene to early Miocene. Ursid migration from Asia to North America would therefore have also been very likely to occur during this time.[4] In the late Neogene three major carnivoran migrations that definitely included ursids are recognized between Eurasia and North America. The first (probably 21–18 Ma) was waves of intermittent dispersals including Amphicynodon, Cephalogale and Ursavus. The second migration occurred about 7–8 Ma and included Agriotherium – this was unusual among ursoids in that it also colonised sub-Saharan Africa. The third wave took place in the early Pliocene 4 Ma, consisting of Ursus.[5]

The giant panda's taxonomy has long been debated. Its original classification by Armand David in 1869 was within the bear genus Ursus, but in 1870 it was reclassified by Alphonse Milne-Edwards to the raccoon family.[6] In recent studies, the majority of DNA analyses suggest that the giant panda has a much closer relationship to other bears and should be considered a member of the family Ursidae.[7] 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 raccoons in Procyonidae or in its own family, the Ailuridae. Multiple similarities between the two pandas, including the presence of false thumbs, 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.[8] 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.

Koalas are often referred to as bears due to their appearance; they are not bears, however, but marsupials.

Classification

Brown Bear Ursus arctos, at the Moscow Zoo
Asiatic Black Bear Ursus thibetanus, at the Wrocław Zoo, Poland
Sun Bear Helarctos malayanus, at the Columbus Zoo
Giant Panda Ailuropoda melanoleuca, "Tian Tian"

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 (see Ursid hybrids).

Biology

Despite being quadrupeds, bears can stand and sit similarly to humans.

Bears are generally bulky and robust animals with relatively short legs. Unlike other land carnivorans, bears stand and walk on the soles of their feet rather than on their toes. They distribute their weight toward the hindfeet which makes then look lumbering when they walk. They are still quite fast with the brown bear reaching 30 mph although they are still slower than felines and canines. Bear can stand on their hindfeet and sit up straight with remarkable balance. Bears have non-retractable claws which are used for digging, climbing, tearing and catching prey. Their ears are rounded.

Dentition

Unlike most other members of the Carnivora, bears have relatively undeveloped carnassial teeth, and their teeth are adapted for a diet that includes a significant amount of vegetable matter. The canine teeth are large, and the molar teeth flat and crushing. There is considerable variation in dental formula even within a given species. It has been suggested that this indicates bears are still in the process of evolving from a carnivorous to a predominantly herbivorous diet. Polar bears appear to have secondarily re-evolved fully functional carnassials, as their diet has switched back towards carnivory.[9] The dental formula for living bears is:

Dentition
3.1.2-4.2
3.1.2-4.3

Diet & Interspecific Interactions

Their carnivorous reputation non-withstanding, most bears have adopted a diet of more plant than animal matter and are completely opportunistic omnivores. One exception is the Polar Bear, which has adopted a diet mainly of marine mammals to survive in the Arctic. The other exception is the Giant Panda which has adopted a diet mainly of bamboo. The Sloth Bear, though not as specialized as the previous two species, has lost several front teeth usually seen in bears and developed a long, suctioning tongue in order to feed on the termites and other burrowing insects that they favor. All bears will feed on any food source that becomes available. When taking warm-blooded animals, bears will typically take small or young animals, because of the endurance and potential danger that comes with attacking large prey. Although (besides Polar Bears) both species of black bear and the Brown Bear can sometimes take large prey, such as ungulates. Often, bears will feed on other large animals when they encounter a carcass, whether or not the carcass is claimed by or is the kill of another predator. This competition is the main source of interspecies conflict. Bears are typically the apex predators in their range due to their size and power, and can defend a carcass against nearly all comers. Mother bears also can usually defend their cubs against other predators. The Tiger is the only known predator known to regularly prey on adult bears, including Sloth Bears, Asiatic Black Bears, Giant Pandas, Sun Bears and small Brown Bears.

Reproduction

The bear's courtship period is very brief. Bears in northern climates reproduce seasonally, usually after a period of inactivity similar to hibernation, although tropical species breed all year round. 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. Male bears, especially Polar and Brown Bears, will kill and sometimes devour cubs born to another father in order to induce a female to breed again. Female bears are often successful in driving off males in protection of their cubs, despite being rather smaller.

Winter dormancy

Cub polar bear is nursing 2.OGG
Polar bear mother is nursing her cub

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[citation needed] because they need not awake through the entire period, but they are more quickly and easily awakened at the end of their hibernation. They have to stay in a den for the whole hibernation.

Relationship with humans

Polar bear at Wapusk National Park, Canada

Some species, such as the polar bear, American black bear, Sloth Bear and the brown bear, are dangerous to humans, especially in areas where they have become used to people. On the west coast of Canada, the American black bear has become an integral part of the silviculture industries, specifically treeplanting. The bears are coaxed into areas of harvested forest to "flush out" the other wildlife, i.e. moose, which are a far greater threat to planters. All bears are physically powerful and are likely capable of fatally attacking a person, but they, for the most part, are shy, easily frightened and will avoid humans. The danger that bears pose is often vastly exaggerated, in part by the human imagination. However, when a mother feels her cubs are threatened, she will behave ferociously. It is recommended to give all bears a wide berth because they are behaviorally unpredictable.

Laws have been passed in many areas of the world to protect bears from hunters habitat destruction. Some populated areas with bear populations have also outlawed the feeding of bears, including allowing them access to garbage or other food waste. Bears in captivity have been trained to dance, box, or ride bicycles; however, this use of the animals became controversial in the late 20th century. Bears were kept for baiting in Europe at least since the 16th century.

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.[10] Bear meat must be cooked thoroughly as it can often be infected with trichinellosis. [11] [12] [13]

Culture

Myth and legend

"En uheldig bjørnejakt" (An Unfortunate Bear Hunt) by Theodor Kittelsen.
Onikuma from Ehon Hyaku Monogatari
According to his hagiography, a bear killed Saint Corbinian's pack horse on the way to Rome and so the saint commanded it to carry his load. Once he arrived in Rome, however, he let the bear go.

Some evidence has been brought to light on 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. The bear is the national animal of Finland.

This kind of attitude is reflected in the traditional Russian fairy tale "Morozko", whose arrogant protagonist Ivan tries to kill a mother bear and her cubs — and is punished and humbled by having his own head turned magically into a bear's head and being subsequently shunned by human society.

"The Brown Bear of Norway" is a Scottish fairy tale telling the adventures of a girl who married a prince magically turned into a bear, and who managed to get him back into a human form by the force of her love and after many trials and difficulties.

There has been evidence about early bear worship in China and among the Ainu culture as well (see Iomante). Korean people in their mythology identify the bear as their ancestor and symbolic animal. According to the Korean legend, a god imposed a difficult test on a she-bear, and when she passed it the god turned her into a woman and married her.

In addition, the Proto-Indo-European word for bear, *h₂ŕ̥tḱos (ancestral to the Greek arktos, Latin ursus, Welsh arth (cf. Arthur), Albanian ari, Armenian arj, Sanskrit ṛkṣa, Hittite ḫartagga) seems to have been subject to taboo deformation or replacement in some langauges (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).[14] Thus some Indo-European language groups do not share the same PIE root. 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 rakṣas, meaning "harm, injury".[15]

Legends of saints taming bears are common in the Alpine zone. In the arms of the bishopric of Freising (see illustration) the bear is the dangerous totem animal tamed by St. Corbinian and made to carry his civilised baggage over the mountains. A bear also features prominently in the legend of St. 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. Similar stories are told of Saint Gall and Saint Columbanus. This recurrent motif was used by the Church as a symbol of the victory of Christianity over Paganism, represented by the fiery.[16]

Imaginary bears are a popular feature of many children's stories including Goldilocks and the Three Bears, the Berenstein Bears, and Winnie the Pooh.

The constellations Ursa Major and Ursa Minor represent bears.

Symbolic use

The Russian bear is a common National personification for Russia (as well as the Soviet Union) and even Germany. 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.

Bears appear in the canting arms of Berne and Berlin.

Also, "bear", "bruin", or specific types of bears are popular nicknames or mascots, e.g. for sports teams (Chicago Bears, Boston Bruins); and a bear cub called Misha was mascot of the 1980 Summer Olympics in Moscow, USSR.

Smokey Bear has become a part of American culture since his introduction in 1944. Known to almost all Americans, he and his message, "Only You Can Prevent Forest Fires" (updated in 2001 to "Only You Can Prevent Wildfires") has been a symbol of preserving woodlands.[17] Smokey wears a hat similar to one worn by many U.S. state police officers, giving rise to the CB slang "bear" or "Smokey" for the highway patrol.

Figures of speech

The physical attributes and behaviours 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 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.
  • A bear hug is typically a tight hug that involves wrapping one's arms around another person, often leaving that person's arms immobile. It was used in the Ronald Reagan political ad "Bear in the woods."
  • Bear tracking - in the old Western states of the U.S. and to this day in the former Dakota Territory, the expression, "You ain't just a bear trackin'.", is used to mean "You ain't lying" or "That's for sure" or "You're not just blowing smoke". This expression evolved as an outgrowth of the experience pioneer hunters and mountainmen had when tracking bear. Bears often lay down false tracks and are notorious for doubling back on anything tracking them. If you are not following bear tracks, you are not following false trails or leads in your thoughts, words or deeds.
  • In Korean culture a person is referred to as being "like a bear" when they are stubborn or not sensitive to what is happening around their surroundings. Used as a phrase to call a person "stubborn bear."
  • The Bible compares King David's "bitter warriors", who fight with such fury that they could overcome many times their number of opponents, with "a bear robbed of her whelps in the field" (2 Book of Samuel, 17, 8 - see [1]). The term "a bereaved bear" (דב שכול), derived from this Biblical source, is still used in the literary Hebrew of contemporary Israel.

Teddy bears

Around the world, many children have stuffed animals in the form of bears.

Names

In Scandinavia the word for bear is Björn (or Bjørn), and is a relatively common given name for males. The use of this name is ancient and has been found mentioned in several runestone inscriptions.[18] The name was also used by J.R.R. Tolkien in his book "The Hobbit", where a bear-like character is named Beorn.

The female first name "Ursula", originally derived from a Christian saint's name and common in English- and German-speaking countries, means "Little she-bear" (dimunitive of Latin "ursa"). In Switzerland the male first name "Urs" is especially popular.

In Russian and other Slavic languages, the word for bear, "Medved" (медведь), and variants or derivatives such as Medvedev are common surnames.

The Irish family name "McMahon" means "Son of Bear" in Irish.

One of widely held etymological explanations for the common name "Arthur" is that it originally meant "bear-like".

In East European Jewish communities, the name "Ber" (בער) — Yiddish cognate of "Bear" — has been attested as a common male first name, at least since the 18th century, and was among others the name of several prominent Rabbis. The Yiddish "Ber" is still in use among Orthodox Jewish communities in Israel, the US and other countries.

With the transition from Yiddish to Hebrew under the influence of Zionism, the Hebrew word for "bear", "Dov" (דב), was taken up in contemporary Israel and is at present among the commonly used male first names in that country.

"Ten Bears" (Paruasemana) was the name of a well-known 19th Century chieftain among the Comanche. Also among other Native American tribes, bear-related names are attested.

References

  1. ^ "Slovakia warns of tipsy bears". http://www.earthtimes.org/articles/show/241001,slovakia-warns-of-tipsy-bears.html. Retrieved on 2008-11-11. 
  2. ^ Kemp, T.S. (2005). The Origin and Evolution of Mammals. Oxford University Press. ISBN 0198507607. 
  3. ^ Wang, Xiaoming, Malcolm C. McKenna, and Demberelyin Dashzeveg (2005). "Amphicticeps and Amphicynodon (Arctoidea, Carnivora) from Hsanda Gol Formation, Central Mongolia and Phylogeny of Basal Arctoids with Comments on Zoogeography". American Museum Novitates (3483): 57. http://www.nhm.org/expeditions/rrc/wang/documents/Wangetal2005ShandGolarctoids.pdf. 
  4. ^ Wang Banyue and Qiu Zhanxiang (2005). "Notes on Early Oligocene Ursids (Carnivora, Mammalia) from Saint Jacques, Nei Mongol, China" (PDF). Bulletin of the American Museum of Natural History 279 (279): 116–124. doi:10.1206/0003-0090(2003)279<0116:C>2.0.CO;2. http://digitallibrary.amnh.org/dspace/bitstream/2246/447/22/B279a05.pdf. 
  5. ^ Qiu Zhanxiang (2003). "Dispersals of Neogene Carnivorans between Asia and North America" (PDF). Bulletin American Museum of Natural History 279 (279): 18–31. doi:10.1206/0003-0090(2003)279<0018:C>2.0.CO;2. http://digitallibrary.amnh.org/dspace/bitstream/2246/447/25/B279a02.pdf. 
  6. ^ Lindburg, Donald G. (2004). Giant Pandas: Biology and Conservation, pp. 7–9. University of California Press
  7. ^ Olaf R. P. Bininda-Emonds. "Phylogenetic Position of the Giant Panda". In Lindburg, Donald G. (2004) Giant Pandas: Biology and Conservation, pp. 11–35. University of California Press
  8. ^ The Brown Bear: Father of the Polar Bear?, Alaska Science Forum
  9. ^ Bunnell, Fred (1984). Macdonald, D.. ed. The Encyclopedia of Mammals. New York: Facts on File. pp. 87. ISBN 0-87196-871-1. 
  10. ^ "BBC Test kit targets cruel bear trade". http://news.bbc.co.uk/2/hi/science/nature/6742671.stm. 
  11. ^ "Trichinellosis Associated with Bear Meat". http://www.cdc.gov/MMWR/preview/mmwrhtml/mm5327a2.htm. Retrieved on 2006-10-04. 
  12. ^ "BBC News - Bear meat poisoning in Siberia". http://news.bbc.co.uk/1/hi/world/europe/41529.stm. Retrieved on 2006-10-04. 
  13. ^ "Finnish Food Safety Authority: Bear meat must be inspected before serving in restaurants". http://www.evira.fi/portal/en/food/current_issues/?id=346. Retrieved on 2006-10-04. 
  14. ^ Votruba, Martin. "Bears". Slovak Studies Program. University of Pittsburgh. http://www.pitt.edu/~votruba/qsonhist/bear.html. Retrieved on 2009-03-12. 
  15. ^ The Brown One, The Honey Eater, The Shaggy Coat, The Destroyer
  16. ^ Michel Pastoreau (2007)L'ours. Historie d'un roi déchu
  17. ^ Ad Council : Forest Fire Prevention - Smokey Bear (1944–Present)
  18. ^ http://hildebrand.raa.se/arkeologi/uppland.asp

Further reading

Find more about bears on Wikipedia's sister projects:
Definitions from Wiktionary

Textbooks from Wikibooks
Quotations from Wikiquote
Source texts from Wikisource
Images and media from Commons
News stories from Wikinews
Learning resources from Wikiversity

Ursidae from Wikispecies
  • Bears of the World, Terry Domico, Photographs by Terry Domico and Mark Newman, Facts on File, Inc, 1988, hardcover, ISBN 0-8160-1536-8
  • The Bear by William Faulkner
  • Brunner, Bernd: Bears — A Brief History. New Haven and London: Yale University Press, 2007

See also

External links

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