Ursidae

クマ科

関

Ailuropoda、bear、black bear、giant panda、grizzly bear、polar bear、Ursus

　

WordNet

1. bears and extinct related forms (同)family Ursidae
2. move while holding up or supporting; "Bear gifts"; "bear a heavy load"; "bear news"; "bearing orders"
3. massive plantigrade carnivorous or omnivorous mammals with long shaggy coats and strong claws
4. an investor with a pessimistic market outlook; an investor who expects prices to fall and so sells now in order to buy later at a lower price
5. have rightfully; of rights, titles, and offices; "She bears the title of Duchess"; "He held the governorship for almost a decade" (同)hold
6. take on as ones own the expenses or debts of another person; "Ill accept the charges"; "She agreed to bear the responsibility" (同)take_over, accept, assume
7. bring forth, "The apple tree bore delicious apples this year"; "The unidentified plant bore gorgeous flowers" (同)turn_out
8. have; "bear a resemblance"; "bear a signature"
9. only the giant panda: in some classifications considered a genus of the separate family Ailuropodidae (同)genus Ailuropoda
10. type genus of Ursidae: brown bears; in some classifications genus Ursus includes all bears (同)genus Ursus

PrepTutorEJDIC

1. 〈C〉『クマ』 / 〈C〉乱暴者 / 〈C〉(株式で)売り方 / 《the B-》クマ座
2. 《しばしば受動態で》〈子〉'を'『産む』 / 〈花〉'を'『つける』,〈実〉'を'『結ぶ』;〈利子など〉'を'生む / 〈重さ〉'を'『支える』,‘に'耐える;〈物〉'を'載せている / 《通例否定構文で》〈人が〉…'を'『がまんする』,こらえる / 《通例否定構文で》〈物事が〉…‘に'ふさわしい,‘の'価値がある / 〈義務・責任など〉'を'負う,負担する;〈罰など〉'を'受ける,こうむる / 《文》…'を'『運ぶ』,持って行く,連れて行く / 〈情報・うわさなど〉'を'伝える,広める / 〈力など〉'を'与える,提供する / 〈武器・紋章など〉'を'身につけている,帯びている / 〈ある性質・特徴〉'を'示す,持っている / 〈ある感情〉…'を'心にいだく,持つ / 《副詞[句]を伴って》…'を'押す,突く / 《副詞[句]を伴って》(…の方に)向く,進む《+『toward』+『名』》 / 《副詞[句]を伴って》(…の)方向(位置)にある / 子を産む;実を結ぶ / …に向かって努力する / …にぐっと押し寄せる

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2016/04/11 06:45:58」(JST)

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This article is about the placental family. For the koala and extinct bear-like marsupials, see Phascolarctidae.

"Ursine" redirects here. For the village, see Ursine, Nevada. For other uses, see Bear (disambiguation).

Bears Temporal range: 38–0 Ma PreЄ Є O S D C P T J K Pg N Late Eocene – Recent
Captive brown bear at the Polar Zoo.
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Carnivora
Suborder:	Caniformia
Family:	Ursidae G. Fischer de Waldheim, 1817
Genera
Ailuropoda Helarctos Melursus Ursus Tremarctos Agriarctos † Agriotherium † Amphicticeps † Amphicynodon † Arctotherium † Arctodus † Indarctos † Kolponomos † Parictis † Plionarctos † Ursavus †

Bears are mammals of the family Ursidae. Bears are classified as caniforms, or doglike carnivorans, with the pinnipeds being their closest living relatives. Although only eight species of bears are extant, they are widespread, appearing in a wide variety of habitats throughout the Northern Hemisphere and partially in the Southern Hemisphere. Bears are found on the continents of North America, South America, Europe, and Asia.

Common characteristics of modern bears include large bodies with stocky legs, long snouts, shaggy hair, plantigrade paws with five nonretractile claws, and short tails. While the polar bear is mostly carnivorous, and the giant panda feeds almost entirely on bamboo, the remaining six species are omnivorous with varied diets.

With the exception of courting individuals and mothers with their young, bears are typically solitary animals. They are generally diurnal, but may be active during the night (nocturnal) or twilight (crepuscular), particularly around humans. Bears possess an excellent sense of smell and, despite their heavy build and awkward gait, are adept runners, climbers, and swimmers. In autumn, some bear species forage large amounts of fermented fruits, which affects their behavior. Bears use shelters, such as caves and burrows, as their dens; most species occupy their dens during the winter for a long period (up to 100 days) of sleep similar to hibernation.

Bears have been hunted since prehistoric times for their meat and fur. With their tremendous physical presence and charisma, they play a prominent role in the arts, mythology, and other cultural aspects of various human societies. In modern times, the bears' existence has been pressured through the encroachment on 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 are prohibited, but still ongoing.

Etymology

The English word "bear" comes from Old English bera and belongs to a family of names for the bear in Germanic languages that originate from an adjective meaning "brown". 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.

The reconstructed Proto-Indo-European name of the bear is *h₂ŕ̥tḱos, whence Sanskrit r̥kṣa, Avestan arša, Greek ἄρκτος (arktos), Latin ursus, Welsh arth (whence perhaps "Arthur"), Albanian ari, Armenian արջ (arj). Also compared is Hittite ḫartagga-, the name of a monster or predator. In the binomial name of the brown bear, Ursus arctos, Linnaeus simply combined the Latin and Greek names.

The Proto-Indo-European (PIE) word for bear, *h₂ŕ̥tḱos seems to have been subject to taboo deformation or replacement in some languages (as was the word for wolf, wlk^wos), resulting in the use of numerous unrelated words with meanings like "brown one" (English bruin) and "honey-eater" (Slavic medved). Thus, some Indo-European language groups do not share the same PIE root.

Evolutionary history

The family Ursidae is one of nine families in the suborder Caniformia, or "doglike" carnivores, within the order Carnivora. Bears' closest living relatives are the pinnipeds, canids, and musteloids.

The following synapomorphic (derived) traits set bears apart from related families:

• presence of an alisphenoid canal
• paroccipital processes that are large and not fused to the auditory bullae
• auditory bullae are not enlarged
• lacrimal bone is vestigial
• cheek teeth are bunodont and hence indicative of a broad, hypocarnivorous (not strictly meat-eating) diet (although hypercarnivorous (strictly meat-eating) taxa are known from the fossil record)
• carnassials are flattened

Additionally, members of this family possess posteriorly oriented M2 postprotocrista molars, elongated m2 molars, and a reduction of the premolars.

Modern 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 on the authority).

Fossil bears

Plithocyon armagnacensis skull

The earliest members of Ursidae belong to the extinct subfamily Amphicynodontinae, including Parictis (late Eocene to early middle Miocene, 38–18 Mya) and the slightly younger Allocyon (early Oligocene, 34–30 Mya), both from North America. These animals looked very different from today's bears, being small and raccoon-like in overall appearance, and diets perhaps more similar to that of a badger. Parictis does not appear in Eurasia and Africa until the Miocene. It is unclear whether late-Eocene ursids were also present in Eurasia, although faunal exchange across the Bering land bridge may have been possible during a major sea level low stand as early as the late Eocene (about 37 Mya) and continuing into the early Oligocene. European genera morphologically are very similar to Allocyon, and also the much younger American Kolponomos (about 18 Mya), are known from the Oligocene, including Amphicticeps and Amphicynodon.

The raccoon-sized, dog-like Cephalogale is the oldest-known member of the subfamily Hemicyoninae, which first appeared during the middle Oligocene in Eurasia about 30 Mya ago. The subfamily also includes the younger genera Phoberocyon (20–15 Mya), and Plithocyon (15–7 Mya).

A Cephalogale-like species gave rise to the genus Ursavus during the early Oligocene (30–28 Mya); this genus proliferated into many species in Asia and is ancestral to all living bears. Species of Ursavus subsequently entered North America, together with Amphicynodon and Cephalogale, during the early Miocene (21–18 Mya).

Members of the living lineages of bears diverged from Ursavus between 15 and 20 Mya ago, likely via the species Ursavus elmensis. Based on genetic and morphological data, the Ailuropodinae (pandas) were the first to diverge from other living bears about 19 Mya ago, although no fossils of this group have been found before about 5 Mya.

The New World short-faced bears (Tremarctinae) differentiated from Ursinae following a dispersal event into North America during the mid-Miocene (about 13 Mya). They invaded South America (~1 Ma) following formation of the Isthmus of Panama. Their earliest fossil representative is Plionarctos in North America (~ 10–2 Ma). This genus is probably the direct ancestor to the North American short-faced bears (genus Arctodus), the South American short-faced bears (Arctotherium), and the spectacled bears, Tremarctos, represented by both an extinct North American species (T. floridanus), and the lone surviving representative of the Tremarctinae, the South American spectacled bear (T. ornatus).

Fossil of cave bear (Ursus spelaeus)

The subfamily Ursinae experienced a dramatic proliferation of taxa about 5.3–4.5 Mya ago, coincident with major environmental changes; with the first members of the genus Ursus also appearing around this time. The sloth bear is a modern survivor of one of the earliest lineages to diverge during this radiation event (5.3 Mya); it took on its peculiar morphology, related to its diet of termites and ants, no later than by the early Pleistocene. By 3–4 Mya ago, the species Ursus minimus appears in the fossil record of Europe; apart from its size, it was nearly identical to today's Asiatic black bear. It is likely ancestral to all bears within Ursinae, perhaps aside from the sloth bear. Two lineages evolved from U. minimus: the black bears (including the sun bear, the Asiatic black bear, and the American black bear); and the brown bears (which includes the polar bear). Modern brown bears evolved from U. minimus via Ursus etruscus, which itself is ancestral to both the extinct Pleistocene cave bear and today's brown and polar bears. Species of Ursinae have migrated repeatedly into North America from Eurasia as early as 4 Mya during the early Pliocene.

The fossil record of bears is exceptionally good. Direct ancestor-descendent relationships between individual species are often fairly well established, with sufficient intermediate forms known to make the precise cut-off between an ancestral and its daughter species subjective.

Other extinct bear genera include Agriarctos, Indarctos, and Agriotherium (sometimes placed within hemicyonids).

Taxonomic revisions of living bear species

The giant panda's taxonomy (subfamily Ailuropodinae) 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. 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. Estimates of divergence dates place the giant panda as the most ancient offshoot among living taxa within Ursidae, having split from other bears as recently as 11.6 Mya to as distantly as 22.1 Mya. The red panda was included within Ursidae in the past. However, more recent research does not support such a conclusion, and instead places it in its own family Ailuridae, in superfamily Musteloidea along with Mustelidae, Procyonidae, and Mephitidae. Multiple similarities between the two pandas, including the presence of false thumbs, are thus thought to represent an example of convergent evolution for feeding primarily on bamboo.

The mitochondrial DNA of brown bears of Alaska's ABC Islands is more closely related to polar bears than to brown bears elsewhere in the world. This is because of repeated historical interbreeding between polar bears and brown bears on the islands. Also, the very rare Tibetan blue bear is a type of brown bear. Koalas are often referred to as bears due to their appearance; however, they are marsupials, not bears.

Classification

Brown bear (Ursus arctos)

Asian black bear (Ursus thibetanus)

Sun bear (Helarctos malayanus)

Giant panda (Ailuropoda melanoleuca)

Spectacled bear (Tremarctos ornatus)

Indian sloth bear (Melursus ursinus ursinus)

American black bear (Ursus americanus)

Polar bear (Ursus maritimus)

Syrian brown bears (Ursus arctos syriacus)

(Extant species in bold, extinct taxa marked with †.)

• Family Ursidae
  • Subfamily Ailuropodinae
    • † Ailurarctos
      • † Ailurarctos lufengensis
      • † Ailurarctos yuanmouenensis
    • Ailuropoda (pandas)
      • † Ailuropoda baconi
      • † Ailuropoda fovealis
      • Ailuropoda melanoleuca – giant panda
        • Ailuropoda melanoleuca melanoleuca; giant panda
        • Ailuropoda melanoleuca qinlingensis; Qinling panda
      • † Ailuropoda microta
      • † Ailuropoda wulingshanensis
  • Subfamily Tremarctinae
    • † Plionarctos
      • † Plionarctos edensis
      • † Plionarctos harroldorum
    • Tremarctos (spectacled bears)
      • Tremarctos ornatus – spectacled bear
      • † Tremarctos floridanus – Florida spectacled bear
    • † Arctodus
      • † Arctodus simus – giant short-faced bear
      • † Arctodus pristinus
    • † Arctotherium
      • † Arctotherium angustidens
      • † Arctotherium bonariense
      • † Arctotherium brasilense
      • † Arctotherium latidens
      • † Arctotherium tarijense
      • † Arctotherium vetustum
      • † Arctotherium wingei
  • Subfamily Ursinae
    • † Ursavus
      • † Ursavus brevirhinus
      • † Ursavus depereti
      • † Ursavus elmensis
      • † Ursavus pawniensis
      • † Ursavus primaevus
      • † Ursavus tedfordi
    • † Indarctos
      • † Indarctos anthraciti
      • † Indarctos arctoides
      • † Indarctos atticus
      • † Indarctos nevadensis
      • † Indarctos oregonensis
      • † Indarctos salmontanus
      • † Indarctos vireti
      • † Indarctos zdanskyi
    • † Agriotherium
      • † Agriotherium inexpetans
      • † Agriotherium schneideri
      • † Agriotherium sivalensis
    • Melursus
      • Melursus ursinus – sloth bear
        • Melursus ursinus inornatus; Sri Lankan sloth bear
        • Melursus ursinus ursinus; Indian sloth bear
    • Helarctos
      • Helarctos malayanus – sun bear
        • Helarctos malayanus malayanus
        • Helarctos malayanus euryspilus; Borneo sun bear
    • Ursus
      • † Ursus rossicus
      • † Ursus sackdillingensis
      • † Ursus minimus
      • Ursus thibetanus – Asian black bear
        • Ursus thibetanus formosanus; Formosan black bear
        • Ursus thibetanus gedrosianus
        • Ursus thibetanus japonicus; Japanese black bear
        • Ursus thibetanus laniger
        • Ursus thibetanus mupinensis
        • Ursus thibetanus thibetanus
        • Ursus thibetanus ussuricus; Manchurian black bear or Ussuri black bear
      • † Ursus abstrusus
      • Ursus americanus – American black bear
        • Ursus americanus altifrontalis, Olympic black bear
        • Ursus americanus amblyceps, New Mexico black bear
        • Ursus americanus americanus, eastern black bear
        • Ursus americanus californiensis, California black bear
        • Ursus americanus carlottae, Haida Gwaii black bear or Queen Charlotte black bear
        • Ursus americanus cinnamomum, cinnamon bear
        • Ursus americanus emmonsii, glacier bear
        • Ursus americanus eremicus, Mexican black bear
        • Ursus americanus floridanus, Florida black bear
        • Ursus americanus hamiltoni, Newfoundland black bear
        • Ursus americanus kermodei, Kermode bear or spirit bear
        • Ursus americanus luteolus, Louisiana black bear
        • Ursus americanus machetes, West Mexico black bear
        • Ursus americanus perniger, Kenai black bear
        • Ursus americanus pugnax, Dall black bear
        • Ursus americanus vancouveri, Vancouver Island black bear
      • † Ursus etruscus
      • Ursus arctos – brown bear
        • Ursus arctos arctos; Eurasian brown bear
        • Ursus arctos alascensis
        • Ursus arctos beringianus; Kamchatka brown bear or Far Eastern brown bear
        • † Ursus arctos californicus; California golden bear
        • † Ursus arctos crowtheri; Atlas bear
        • † Ursus arctos dalli
        • Ursus arctos gobiensis; Gobi bear (very rare)
        • Ursus arctos horribilis; grizzly bear, North American brown bear, or silvertip bear
        • Ursus arctos isabellinus; Himalayan brown bear or Himalayan red bear
        • Ursus arctos lasiotus; Ussuri brown bear or black grizzly
        • Ursus arctos middendorffi; Kodiak bear
        • † Ursus arctos nelsoni; Mexican grizzly bear
        • Ursus arctos piscator; Bergman's bear (extinct?)
        • Ursus arctos pruinosus; Tibetan blue bear, Tibetan bear, or Himalayan blue bear
        • Ursus arctos sitkensis
        • Ursus arctos syriacus; Syrian (brown) bear
      • Ursus maritimus – polar bear
        • Ursus maritimus maritimus
        • † Ursus maritimus tyrannus (possibly a brown bear)
      • † Ursus savini
      • † Ursus deningeri
      • † Ursus spelaeus – cave bear
      • † Ursus inopinatus, MacFarlane's bear (cryptid; possibly a hybrid)
  • † Kolponomos
    • † Kolponomos clallamensis
    • † Kolponomos newportensis

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; these names have since been reduced in rank to subgeneric rank.

A number of hybrids have been bred between American black, brown, and polar bears.

Biology

Morphology

Unlike most other Carnivora, bears have plantigrade feet

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

Bears are generally bulky and robust animals with relatively short legs. They are sexually dimorphic with regard to size, with the males being larger. Larger species tend to show increased levels of sexual dimorphism in comparison to smaller species, and where a species varies in size across its distribution, individuals from larger-sized areas tend also to vary more. Bears include the most massive terrestrial members of the order Carnivora. Some exceptional polar bears and Kodiak bears (a brown bear subspecies) have been weighed at over 750 kg (1,650 lb). As to which species is the largest depends on whether the assessment is based on which species has the largest individuals (brown bears) or on the largest average size (polar bears), as some races of brown bears are much smaller than polar bears. Adult male Kodiak bears average 480 to 533 kg (1,058 to 1,175 lb) compared to an average of 386 to 408 kg (851 to 899 lb) in adult male polar bears, per the Guinness Book of World Records. The smallest bears are the sun bears of Asia, which weigh an average of 65 kg (143 lb) for the males and 45 kg (99 lb) for the females, though the smallest mature females can weigh only 20 kg (44 lb). All "medium"-sized bear species (which include the other five extant species) are around the same average weight, with males averaging around 100 to 120 kg (220 to 260 lb) and females averaging around 60 to 85 kg (132 to 187 lb), although it is not uncommon for male American black bears to considerably exceed "average" weights. Head-and-body length can range from 120 cm (47 in) in sun bears to 300 cm (120 in) in large polar and brown bears and shoulder height can range from 60 cm (24 in) to over 160 cm (63 in) in the same species, respectively. The tails of bears are often considered a vestigial feature and can range from 3 to 22 cm (1.2 to 8.7 in).

Unlike most other land carnivorans, bears are plantigrade. They distribute their weight toward the hind feet, which makes them look lumbering when they walk. They are still quite fast, with the brown bear reaching 48 km/h (30 mph), although they are still slower than felines and canines. Bears can stand on their hind feet and sit up straight with remarkable balance. Bears' nonretractable claws are used for digging, climbing, tearing, and catching prey. Their ears are rounded.

Bears have an excellent sense of smell, better than the dogs (Canidae), or possibly any other mammal. This sense of smell is used for signalling between bears (either to warn off rivals or detect mates) and for finding food. Smell is the principal sense used by bears to find most of their food.

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. Considerable variation occurs in dental formula even within a given species. This may indicate bears are still in the process of evolving from carnivorous to predominantly herbivorous diets. Polar bears appear to have secondarily re-evolved carnassial-like cheek teeth, as their diets have switched back towards carnivory. The dental formula for living bears is: 3.1.2–4.23.1.2–4.3

Distribution and habitat

See also: List of carnivorans by population

Bears are primarily found in the Northern Hemisphere, and with one exception, only in Asia, North America, and Europe. The single exception is the spectacled bear (Tremarctos ornatus); native to South America it inhabits the Andean region. The Atlas bear, a subspecies of the brown bear, was the only bear native to Africa. It was distributed in North Africa from Morocco to Libya, but has been extinct since around the 1870s. The most widespread species is the brown bear, which occurs from Western Europe eastwards through Asia to the western areas of North America. The American black bear is restricted to North America, and the polar bear is restricted to the Arctic Sea. All the remaining species are Asian.

With the exception of the polar bear, bears are mostly forest species. Some species, particularly the brown bear, may inhabit or seasonally use other areas, such as alpine scrub or tundra.

Behaviour

Play media

Captive black bear cubs at play.

Bears are generally diurnal, meaning that they are active for the most part during the day. The belief that they are nocturnal apparently comes from the habits of bears that live near humans, which engage in some nocturnal activities, such as raiding trash cans or crops while avoiding humans. The sloth bear of Asia is the most nocturnal of the bears, but this varies by individual, and females with cubs are often diurnal to avoid competition with males and nocturnal predators. Bears are overwhelmingly solitary and are considered to be the most asocial of all the Carnivora. Liaisons between breeding bears are brief, and the only times bears are encountered in small groups are mothers with young or occasional seasonal bounties of rich food (such as salmon runs).

Vocalizations

Bears produce a variety of vocalizations such as:

• Moaning, produced mostly as mild warnings to potential threats or in fear,
• Barking, produced during times of alarm, excitement or to give away the animal's position.
• Huffing, made during courtship or between mother and cubs to warn of danger.
• Growling, produced as strong warnings to potential threats or in anger.
• Roaring, used much for the same reasons as growls and also to proclaim territory and for intimidation.
• Humming, a loud monotonous buzzing sound, primarily employed by cubs.

Diet and interspecific interactions

Asian black bear feeding on berries

Brown bear feeding on infrequent, but predictable, salmon migrations

Most bears have diets of more plant than animal matter and are completely opportunistic omnivores. Some bears will climb trees to obtain mast (edible vegetative or reproductive parts, such as acorns); smaller species that are more able to climb include a greater amount of this in their diets. Such masts can be very important to the diets of these species, and mast failures may result in long-range movements by bears looking for alternative food sources. There are two significant exceptions to this however:

• The polar bear, which has adopted a diet mainly of marine mammals to survive in the Arctic.
• The giant panda, which has adopted a diet mainly of bamboo.

Stable isotope analysis of the extinct giant short-faced bear (Arctodus simus) shows it was also an exclusive meat-eater, probably a scavenger. 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 to feed on the ants, termites, and other burrowing insects they favour. At certain times of the year, these insects can make up 90% of their diets. All bears will feed on any food source that becomes available, the nature of which varies seasonally. A study of Asiatic black bears in Taiwan found they would consume large numbers of acorns when they were most common, and switch to ungulates at other times of the year.

Regarding warm-blooded animals, bears will typically take small or young animals, as they are easier to catch. However, both species of black bears 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 able to defend a carcass against some comers. Mother bears also can usually defend their cubs against other predators.

The tiger is the only predator known to regularly prey on adult bears, including fully grown adults of brown bears, sloth bears, Asiatic black bears, and sun bears. When hunting bears, tigers will position themselves from the leeward side of a rock or fallen tree, waiting for the bear to pass by. When the bear passes, the tiger will spring from an overhead position and grab the bear from under the chin with one forepaw and the throat with the other. The immobilised bear is then killed with a bite to the spinal column. After killing a bear, the tiger will concentrate its feeding on the bear's fat deposits, such as the back, legs and groin.

Breeding

Further information: Brown bear § Reproduction, American black bear § Reproduction and development, Polar bear § Reproduction and lifecycle, Grizzly bear § Reproduction, Asian black bear § Reproduction and life cycle, Spectacled bear § Reproduction, Sloth bear § Reproduction and Giant panda § Reproduction

American black bears mating

The age at which bears reach sexual maturity is highly variable, both between and within species. Sexual maturity is dependent on body condition, which is in turn dependent upon the food supply available to the growing individual. The females of smaller species may have young in as little as two years, whereas the larger species may not rear young until they are four or even nine years old. First breeding may be even later in males, where competition for mates may leave younger males without access to females.

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 one to three, 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 cubs learn to begin hunting with the mother. They will remain with the mother for about 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 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.

Hibernation

Further information: American black bear § Hibernation and Grizzly bear § Hibernation

Play media

Polar bear mother nursing her cub

Many bears of northern regions hibernate in the winter. During hibernation, the bear's metabolism slows down, its body temperature decreases slightly, and its heart rate slows from a normal value of 55 to just 9 beats per minute. Bears normally do not wake during their hibernation, and can go the entire period without eating, drinking, urinating, or defecating. Female bears give birth during the hibernation period, and are roused when doing so.

Relationship with humans

See also: Bear danger

Bear danger area closure sign of a type used in Denali National Park, Alaska

Wojtek the bear with a Polish soldier: during the Battle of Monte Cassino, Wojtek helped move ammunition.

Some species, such as the polar bear, American black bear, grizzly bear, sloth bear, and brown bear, are dangerous to humans, especially in areas where they have become used to people. All bears are physically powerful and are likely capable of fatally attacking a person, but they, for the most part, are shy, are easily frightened and will avoid humans. Injuries caused by bears are rare, but are often widely reported. The danger that bears pose is often vastly exaggerated, in part by the human imagination. However, when a mother feels that her cubs are threatened, she will behave ferociously. It is recommended to give all bears a wide berth; because, they are behaviorally unpredictable.

Where bears raid crops or attack livestock, they may come into conflict with humans. These problems may be the work of only a few bears, but they create a climate of conflict, as farmers and ranchers may perceive all losses as due to bears and advocate the preventive removal of all bears. Mitigation methods may be used to reduce bear damage to crops, and reduce local antipathy towards bears.

Laws have been passed in many areas of the world to protect bears from habitat destruction. Public perception of bears is often very positive, as people identify with bears due to their omnivorous diets, ability to stand on two legs, and symbolic importance, and support for bear protection is widespread, at least in more affluent societies. In more rural and poorer regions, attitudes may be more shaped by the dangers posed by bears and the economic costs they cause to farmers and ranchers. 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.

Bear hunt

Main article: Bear hunting

Some cultures use bears for food and folk medicine. 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. More than 12,000 bile bears are thought to be kept on farms, for their bile, in China, Vietnam, and South Korea. Bear meat must be cooked thoroughly, as it can be infected with Trichinella spiralis, which can cause trichinosis.

Culture

Names

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" (diminutive of Latin ursa). In Switzerland, the male first name "Urs" is especially popular, while the name of the canton and city of Bern is derived from Bär, German for bear. The Germanic name Bernard (including Bernhardt and other forms) means "bear-brave", "bear-hardy", or "bold bear".

In Scandinavia, the male personal names Björn (Sweden, Iceland) and Bjørn (Norway, Denmark), meaning "bear", are relatively common. In Finland, the male personal name Otso is an old poetic name for bear, similar to Kontio.

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.

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.

Myth and legend

For bears in mythology, see Jean de l'Ours, Arcturus, Ursa Major, and Berserker.

There is evidence of prehistoric bear worship. 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 Siberian peoples, considered the bear as the spirit of one's forefathers. This is why the bear (karhu) was a greatly respected animal, with several euphemistic names (such as otso, mesikämmen, and kontio). 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. In the 1970s, this story was adapted into the East German fantasy film The Singing Ringing Tree and broadcast on British television.

Evidence of bear worship has been found in early Chinese and Ainu cultures, 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; when she passed it, the god turned her into a woman and married her.

Legends of saints taming bears are common in the Alpine zone. In the arms of the bishopric of Freising, 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. In the Norse settlements of northern England during the 10th century, a type of "hogback" grave cover of a long narrow block of stone, with a shaped apex like the roof beam of a long house, is carved with a muzzled, thus Christianised, bear clasping each gable end. Though the best collection of these is in the church at Brompton, North Yorkshire, their distribution ranges across northern England and southern Scotland, with a scattered few in the north Midlands and single survivals in Wales, Cornwall, and Ireland; a late group is found in the Orkney Islands.

Bears are a popular feature of many children's stories, including Goldilocks and "The Story of the Three Bears", the Berenstain Bears, and Winnie the Pooh.

• "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, so the saint commanded it to carry his load. Once he arrived in Rome, however, he let the bear go.

• The saddled "bear of St. Corbinian" the emblem of Freising, here incorporated in the arms of Pope Benedict XVI

• Coat of Arms of the Abbey of Saint Gall

• "The Three Bears", Arthur Rackham's illustration to English Fairy Tales, by

Symbolic use

For more details on this topic, see Bear in heraldry.

The British Lion, the Persian Cat and the Russian Bear (see The Great Game)

The Russian bear is a common national personification for Russia (as well as the Soviet Union). The brown bear is also Finland's national animal.

The flag of California

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 also appear in the state seals of California and Missouri.

In the UK, the bear and staff has long featured on the heraldic arms of Warwickshire county.

Bears appear in the canting arms of Bern and Berlin. Bear symbols are used extensively in Berlin street decorations.

Misha, the Russian Bear mascot of the 1980 Moscow Olympic Games

Also, "bear", "bruin", or specific types of bears are popular nicknames or mascots, for example, for sports teams (Bayern Munich, Chicago Bears, California Golden Bears, UCLA Bruins, Boston Bruins); and a bear cub called Misha was mascot of the 1980 Summer Olympics in Moscow, Soviet Union.

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"), have been a symbol of preserving woodlands. Smokey wears a hat similar to one worn by U.S. Forest Service rangers; state police officers in some states wear a similar style, giving rise to the CB slang "bear" or "Smokey" for the highway patrol.

The name Beowulf has been hypothesized to mean "bee-wolf", a kenning for "bear".

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.
• 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". 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 Samuel 17:8 s:Bible (King James)/2 Samuel#Chapter 17). The phrase "a bereaved bear" (דב שכול), derived from this Biblical source, is still used in the literary Hebrew of contemporary Israel.

Teddy bears

Main article: Teddy bear

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

Organizations regarding bears

Two authoritative organizations for seeking scientific information on bear species of the world are the International Association for Bear Research & Management, also known as the International Bear Association (IBA); and the Bear Specialist Group of the Species Survival Commission, a part of the International Union for the Conservation of Nature. These organizations focus on the species' natural history, management, and conservation.

Other organizations exist to further wild bear education and conservation. Bear Trust International works for wild bears and other wildlife through four core program initiatives: 1) Conservation Education, 2) Wild Bear Research, 3) Wild Bear Management, and, 4) Habitat Conservation. Specialty organizations for each of the eight species of bears worldwide include:

• Brown bear: "Vital Ground". 
• Asiatic black bear: "Moon Bears". 
• North American black bear: "Black Bear Conservation Coalition". 
• Polar bear: "Polar Bears International". 
• Sun bear: "Bornean Sun Bear Conservation Centre". 
• Sloth bear: "Wildlife SOS". 
• Andean bear: "Andean Bear Conservation Project". 
• Giant panda: "Chengdu Research Base of Giant Panda Breeding". 

See also

• List of fatal bear attacks in North America
• List of fictional bears
• List of individual bears
• Ursa Minor
• Ursari

References

Further reading

• Bears of the World, Terry Domico, photographs by Terry Domico and Mark Newman, Facts on File, Inc., 1988, hardcover, ISBN 978-0-8160-1536-8.
• The Bear by William Faulkner.
• Brunner, Bernd: Bears: A Brief History. New Haven and London: Yale University Press, 2007.

External links

• The Bears Project – Information, reports and images of European brown bears and other living species
• Western Wildlife Outreach – Information on the history, biology, and conservation of North American Grizzly Bears and Black Bears
• The Bear Book and Curriculum Guide – a compilation of stories about all eight species of bears worldwide, including STEM lessons rooted in bear research, ecology, and conservation

English Journal

• Growth trajectories in the cave bear and its extant relatives: an examination of ontogenetic patterns in phylogeny.

• Fuchs M1, Geiger M2, Stange M3, Sánchez-Villagra MR4.
• BMC evolutionary biology.BMC Evol Biol.2015 Nov 2;15:239. doi: 10.1186/s12862-015-0521-z.
• BACKGROUND: The study of postnatal ontogeny can provide insights into evolution by offering an understanding of how growth trajectories have evolved resulting in adult morphological disparity. The Ursus lineage is a good subject for studying cranial and mandibular shape and size variation in relatio
• PMID 26525575

• Giant pandas (Carnivora: Ailuropoda melanoleuca) and living hominoids converge on lumbar vertebral adaptations to orthograde trunk posture.

• Russo GA1, Williams SA2.
• Journal of human evolution.J Hum Evol.2015 Nov;88:160-79. doi: 10.1016/j.jhevol.2015.06.015. Epub 2015 Sep 2.
• Living hominoids share a common body plan characterized by a gradient of derived postcranial features that distinguish them from their closest living relatives, cercopithecoid monkeys. However, the evolutionary scenario(s) that led to the derived postcranial features of hominoids are uncertain. Expl
• PMID 26341032

• Grizzly bear (Ursus arctos horribilis) locomotion: gaits and ground reaction forces.

• Shine CL1, Penberthy S2, Robbins CT3, Nelson OL4, McGowan CP5.
• The Journal of experimental biology.J Exp Biol.2015 Oct;218(Pt 19):3102-9. doi: 10.1242/jeb.121806. Epub 2015 Aug 7.
• Locomotion of plantigrade generalists has been relatively little studied compared with more specialised postures even though plantigrady is ancestral among quadrupeds. Bears (Ursidae) are a representative family for plantigrade carnivorans, they have the majority of the morphological characteristics
• PMID 26254319

Japanese Journal

• 冬眠するクマ(クマ科) : 腎臓専門医の興味をかきたてる代謝機能の魔術

• Stenvinkel Peter,Jani Alkesh H.,Johnson Richard J.
• Kidney international selections : official journal of the International Society of Nephrology 11(3), 93-99, 2013
• NAID 40019788704

• Identification of the expressed MHC class II DQB gene of the Asiatic black bear, Ursus thibetanus, in Japan

• , , [他],
• Genes & genetic systems 85(2), 147-155, 2010-04-25
• … This is the first such full length expression in the Ursidae. …
• NAID 10029514860

• ヘア・トラップを用いたクマ類の個体数推定法 : 概要と注意点

• 佐藤 喜和,湯浅 卓
• 哺乳類科学 48(1), 101-107, 2008-06-30
• ヘア・トラップによる非侵襲性サンプリングおよび遺伝マーカーを用いた個体識別による捕獲再捕獲法に基づく個体数推定がクマ類を対象に広く実施されるようになり，日本でも各地でこの手法の適用に向けた試行錯誤が進められている．この方法には，動物を捕獲する必要がない，捕獲を伴う方法よりも広い範囲でサンプリングが実施できる，生け捕りに比べ偏りのないサンプリングが期待できる，遺伝マーカーによる標識であるため消失する …
• NAID 10026778341

Related Links

• URSIDAE

URSIDAE

• Ursidae | Define Ursidae at Dictionary.com

00:10 Ursidae is always a great word to know. So is ninnyhammer. Does it mean: So is doohickey. Does it mean: So is lollapalooza. Does it mean: a gadget; dingus; thingumbob. a fool or simpleton; ninny. a printed punctuation ...

Related Pictures

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★リンクテーブル★

リンク元	「Ailuropoda」「クマ科」「Ursus」「giant panda」「polar bear」

「Ailuropoda」

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ジャイアントパンダ属、アイルロ・ダ属、Ailuropoda属

関

bear、black bear、giant panda、grizzly bear、polar bear、Ursidae、Ursus

　

「クマ科」

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ラ

Ursidae

関

クマ属、ジャイアントパンダ属、クマ、クロクマ、ホッキョクグマ、ジャイアントパンダ、グリズリー

「Ursus」

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クマ属、ウルスス属、Ursus属

関

Ailuropoda、bear、black bear、giant panda、grizzly bear、polar bear、Ursidae

　

「giant panda」

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ジャイアントパンダ

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Ailuropoda、bear、black bear、grizzly bear、polar bear、Ursidae、Ursus

「polar bear」

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ホッキョクグマ

関

Ailuropoda、bear、black bear、giant panda、grizzly bear、Ursidae、Ursus