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54-790: Bears are carnivoran mammals of the family Ursidae ( / ˈ ɜːr s ɪ d iː , - d aɪ / ). They are classified as caniforms , or doglike carnivorans. Although only eight species of bears are extant, they are widespread, appearing in a wide variety of habitats throughout most of the Northern Hemisphere and partially in the Southern Hemisphere. Bears are found on the continents of North America , South America , and Eurasia . Common characteristics of modern bears include large bodies with stocky legs, long snouts, small rounded ears, shaggy hair, plantigrade paws with five nonretractile claws, and short tails. While

108-581: A septum . Caniforms have single-chambered or partially divided auditory bullae, composed of a single bone. Initially, the early representatives of carnivorans were small as the creodonts (specifically, the oxyaenids) and mesonychians dominated the apex predator niches during the Eocene, but in the Oligocene, carnivorans became a dominant group of apex predators with the nimravids , and by the Miocene most of

162-440: A correlation between habitat and color pattern; for example spotted or banded species tend to be found in heavily forested environments. Some species like the grey wolf are polymorphic with different individual having different coat colors. The arctic fox ( Vulpes lagopus ) and the stoat ( Mustela erminea ) have fur that changes from white and dense in the winter to brown and sparse in the summer. In pinnipeds and polar bears ,

216-473: A supporting amount of evidence that Miacoidea is an evolutionary grade of carnivoramorphs that, while viverravids are monophyletic basal group, the miacids are paraphyletic in respect to Carnivora (as shown in the phylogeny below). Carnivoramorpha as a whole first appeared in the Paleocene of North America about 60 million years ago. Crown carnivorans first appeared around 42 million years ago in

270-442: A thick insulating layer of blubber helps maintain their body temperature. Carnivorans are arguably the group of mammals of most interest to humans. The dog is noteworthy for not only being the first species of carnivoran to be domesticated , but also the first species of any taxon. In the last 10,000 to 12,000 years, humans have selectively bred dogs for a variety of different tasks and today there are well over 400 breeds. The cat

324-646: A wide array of body plans, varying greatly in size and shape. Carnivora are divided into two suborders , the Feliformia , containing the true felids and several " cat -like" animals; and the Caniformia , containing the true canids and many " dog -like" animals. The feliforms include the Felidae , Viverridae , hyena , and mongoose families, the majority of which live only in the Old World; cats are

378-682: Is a table chart of the extant carnivoran families and number of extant species recognized by various authors of the first (2009 ) and fourth (2014 ) volumes of the Handbook of the Mammals of the World : The canine teeth are usually large, conical, thick and stress resistant. All of the terrestrial species of carnivorans have three incisors on each side of each jaw (the exception is the sea otter ( Enhydra lutris ) which only has two lower incisor teeth). The third molar has been lost. The carnassial pair

432-486: Is an order of placental mammals that have specialized in primarily eating flesh, whose members are formally referred to as carnivorans . The order Carnivora is the sixth largest order of mammals, comprising at least 279 species on every major landmass and in a variety of habitats, ranging from the cold polar regions of Earth to the hyper-arid region of the Sahara Desert and the open seas. Carnivorans exhibit

486-475: Is another domesticated carnivoran and it is today considered one of the most successful species on the planet, due to their close proximity to humans and the popularity of cats as pets. Many other species are popular, and they are often charismatic megafauna . Many civilizations have incorporated a species of carnivoran into their culture: a prominent example is the lion , viewed as a symbol of power and royalty in many societies. Yet many species such as wolves and

540-529: Is from the Proto-Indo-European word *ǵʰwḗr- ~ *ǵʰwér "wild animal". This terminology for the animal originated as a taboo avoidance term: proto-Germanic tribes replaced their original word for bear— arkto —with this euphemistic expression out of fear that speaking the animal's true name might cause it to appear. According to author Ralph Keyes , this is the oldest known euphemism . Bear taxon names such as Arctoidea and Helarctos come from

594-428: Is made up of the fourth upper premolar and the first lower molar teeth. Like most mammals, the dentition is heterodont , though in some species, such as the aardwolf ( Proteles cristata ), the teeth have been greatly reduced and the cheek teeth are specialised for eating insects. In pinnipeds, the teeth are homodont as they have evolved to grasp or catch fish, and the cheek teeth are often lost. In bears and raccoons,

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648-585: 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 very similar to Allocyon , and to the much younger American Kolponomos (about 18 Mya), are known from the Oligocene, including Amphicticeps and Amphicynodon . There has been various morphological evidence linking amphicynodontines with pinnipeds , as both groups were semi-aquatic, otter-like mammals. In addition to

702-551: The Caribbean monk seal ( Neomonachus tropicalis ) in 1952. Some species such as the red fox ( Vulpes vulpes ) and stoat ( Mustela erminea ) have been introduced to Australasia and have caused many native species to become endangered or even extinct. Ursula (given name) Ursula is a feminine given name in several languages. The name is derived from a diminutive of the Latin ursa , which means " bear ". The name

756-477: The Cretaceous–Paleogene extinction event . These early ancestors of carnivorans would have resembled small weasel or genet -like mammals, occupying a nocturnal shift on the forest floor or in the trees, as other groups of mammals like the mesonychians and later the creodonts were occupying the megafaunal faunivorous niche. However, following the extinction of mesonychians and the oxyaenid creodonts at

810-645: The Isthmus of Panama . Their earliest fossil representative is Plionarctos in North America (c. 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

864-558: The Middle Eocene . Their molecular phylogeny shows the extant Carnivora are a monophyletic group, the crown group of the Carnivoramorpha . From there carnivorans have split into two clades based on the composition of the bony structures that surround the middle ear of the skull, the cat-like feliforms and the dog-like caniforms . In feliforms, the auditory bullae are double-chambered, composed of two bones joined by

918-487: The big cats have been broadly hunted, resulting in extirpation in some areas. Habitat loss and human encroachment as well as climate change have been the primary cause of many species going into decline. Four species of carnivorans have gone extinct since the 1600s: Falkland Island wolf ( Dusicyon australis ) in 1876; the sea mink ( Neogale macrodon ) in 1894; the Japanese sea lion ( Zalophus japonicus ) in 1951 and

972-533: The polar bear is mostly carnivorous , and the giant panda is mostly herbivorous , the remaining six species are omnivorous with varying diets. With the exception of courting individuals and mothers with their young, bears are typically solitary animals . They may be diurnal or nocturnal and have an excellent sense of smell . Despite their heavy build and awkward gait, they are adept runners, climbers, and swimmers. Bears use shelters, such as caves and logs, as their dens; most species occupy their dens during

1026-399: The spectacled bear ), and Ursinae (containing six species divided into one to three genera, depending on the authority). Nuclear chromosome analysis show that the karyotype of the six ursine bears is nearly identical, each having 74  chromosomes ( see Ursid hybrid ), whereas the giant panda has 42 chromosomes and the spectacled bear 52. These smaller numbers can be explained by

1080-470: 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. The English word "bear" comes from Old English bera and belongs to a family of names for

1134-504: The ancient Greek ἄρκτος ( arktos ), meaning bear, as do the names " arctic " and " antarctic ", via the name of the constellation Ursa Major , the "Great Bear", prominent in the northern sky. Bear taxon names such as Ursidae and Ursus come from Latin Ursus/Ursa , he-bear/she-bear. The female first name " Ursula ", originally derived from a Christian saint 's name, means "little she-bear" (diminutive of Latin ursa ). In Switzerland,

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1188-757: The bear family with other carnivorans is shown in the following phylogenetic tree , which is based on the molecular phylogenetic analysis of six genes in Flynn (2005) with the musteloids updated following the multigene analysis of Law et al. (2018). Feliformia [REDACTED] Canidae [REDACTED] Ursidae [REDACTED] Pinnipedia [REDACTED] Mephitidae [REDACTED] Ailuridae [REDACTED] Procyonidae [REDACTED] Mustelidae [REDACTED] Note that although they are called "bears" in some languages, red pandas and raccoons and their close relatives are not bears, but rather musteloids . There are two phylogenetic hypotheses on

1242-466: The bear in Germanic languages , such as Swedish björn , also used as a first name. This form is conventionally said to be related to a Proto-Indo-European word for "brown", so that "bear" would mean "the brown one". However, Ringe notes that while this etymology is semantically plausible, a word meaning "brown" of this form cannot be found in Proto-Indo-European. He suggests instead that "bear"

1296-517: The brown bears (which includes the polar bear ). Modern brown bears evolved from U. minimus via Ursus etruscus , which itself is ancestral to the extinct Pleistocene cave bear . Species of Ursinae have migrated repeatedly into North America from Eurasia as early as 4 Mya during the early Pliocene. The polar bear is the most recently evolved species and descended from a population of brown bears that became isolated in northern latitudes by glaciation 400,000 years ago. The relationship of

1350-406: The carnassial pair is secondarily reduced. The skulls are heavily built with a strong zygomatic arch . Often a sagittal crest is present, sometimes more evident in sexually dimorphic species such as sea lions and fur seals , though it has also been greatly reduced in some small carnivorans. The braincase is enlarged with the frontoparietal bone at the front. In most species, the eyes are at

1404-403: The clade Ferae . Ferae includes the closest extant relative of carnivorans, the pangolins , as well as several extinct groups of mostly Paleogene carnivorous placentals such as the creodonts , the arctocyonians , and mesonychians . The creodonts were originally thought of as the sister taxon to the carnivorans, perhaps even ancestral to, based on the presence of the carnassial teeth , but

1458-443: The dental and cranial features, not much of their overall anatomy unites carnivorans as a group. All species of carnivorans are quadrupedal and most have five digits on the front feet and four digits on the back feet. In terrestrial carnivorans, the feet have soft pads. The feet can either be digitigrade as seen in cats, hyenas and dogs or plantigrade as seen in bears, skunks, raccoons, weasels, civets and mongooses. In pinnipeds,

1512-526: The early Pleistocene. By 3–4 Mya, the species Ursus minimus appears in the fossil record of Europe; apart from its size, it was nearly identical to today's Asian 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 Asian black bear, and the American black bear ); and

1566-482: The end of the Eocene, carnivorans quickly moved into this niche, with forms like the nimravids being the dominant large-bodied ambush predators during the Oligocene alongside the hyaenodont creodonts (which similarly produced larger, more open-country forms at the start of the Oligocene). By the time Miocene epoch appeared, most if not all of the major lineages and families of carnivorans had diversified and become

1620-688: The extant carnivoran families have diversified and become the primary terrestrial predators in the Northern Hemisphere. In 1758, the Swedish botanist Carl Linnaeus placed all carnivorans known at the time into the group Ferae (not to be confused with the modern concept of Ferae which also includes pangolins) in the tenth edition of his book Systema Naturae . He recognized six genera: Canis (canids and hyaenids), Phoca (pinnipeds), Felis (felids), Viverra (viverrids, herpestids, and mephitids), Mustela (non-badger mustelids), Ursus (ursids, large species of mustelids, and procyonids). It

1674-992: The extinct bear dogs of the family Amphicyonidae . Below is the cladogram based on McKenna and Bell (1997) classification: † Amphicyonidae [REDACTED] † Amphicynodontidae [REDACTED] Pinnipedia [REDACTED] † Hemicyoninae † Agriotheriinae † Ursavinae Ailuropodinae [REDACTED] Tremarctinae [REDACTED] Ursinae [REDACTED] Giant panda ( Ailuropoda melanoleuca ) [REDACTED] Spectacled bear ( Tremarctos ornatus ) [REDACTED] Sloth bear ( Melursus ursinus ) [REDACTED] Sun bear ( Helarctos malayanus ) [REDACTED] Asian black bear ( Ursus thibetanus ) [REDACTED] American black bear ( Ursus americanus ) [REDACTED] Polar bear ( Ursus maritimus ) [REDACTED] Brown bear ( Ursus arctos ) [REDACTED] Giant panda ( Ailuropoda melanoleuca ) [REDACTED] Carnivora Carnivora ( / k ɑːr ˈ n ɪ v ər ə / kar- NIH -vər-ə )

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1728-407: The front of the face. In caniforms, the rostrum is usually long with many teeth, while in feliforms it is shorter with fewer teeth. The carnassial teeth of feliforms are generally more sectional than those of caniforms. The turbinates are large and complex in comparison to other mammals, providing a large surface area for olfactory receptors . Aside from an accumulation of characteristics in

1782-570: The fusing of some chromosomes, and the banding patterns on these match those of the ursine species, but differ from those of procyonids, which supports the inclusion of these two species in Ursidae rather than in Procyonidae , where they had been placed by some earlier authorities. The earliest members of Ursidae belong to the extinct subfamily Amphicynodontinae, including Parictis (late Eocene to early middle Miocene , 38–18  Mya ) and

1836-456: 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, likely via

1890-407: The limbs have been modified into flippers . Unlike cetaceans and sirenians , which have fully functional tails to help them swim, pinnipeds use their limbs underwater to swim. Earless seals use their back flippers; sea lions and fur seals use their front flippers, and the walrus uses all of its limbs. As a result, pinnipeds have significantly shorter tails than other carnivorans. Aside from

1944-658: The lone surviving representative of the Tremarctinae, the South American spectacled bear ( T. ornatus ). The subfamily Ursinae experienced a dramatic proliferation of taxa about 5.3–4.5 Mya, coincident with major environmental changes; the first members of the genus Ursus appeared 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

1998-415: The male first name "Urs" is especially popular, while the name of the canton and city of Bern is by legend derived from Bär , German for bear. The Germanic name Bernard (including Bernhardt and similar forms) means "bear-brave", "bear-hardy", or "bold bear". The Old English name Beowulf is a kenning , "bee-wolf", for bear, in turn meaning a brave warrior. The family Ursidae is one of nine families in

2052-536: The methods in which mammalogists use to assess the phylogenetic relationships among the carnivoran families has been improved with using more complicated and intensive incorporation of genetics, morphology and the fossil record. Research into Carnivora phylogeny since 1945 has found Fisspedia to be paraphyletic in respect to Pinnipedia, with pinnipeds being either more closely related to bears or to weasels. The small carnivoran families Viverridae, Procyonidae, and Mustelidae have been found to be polyphyletic : Below

2106-520: The most dominant group of large terrestrial predators in Eurasia and North America, with various lineages being successful in megafaunal faunivorous niches at different intervals during the Miocene and later epochs. The order Carnivora belongs to a group of mammals known as Laurasiatheria , which also includes other groups such as bats and ungulates . Within this group the carnivorans are placed in

2160-442: The nature of the carnassial teeth is different between the two groups. In carnivorans the carnassials are positioned near the front of the molar row, while in the creodonts they are positioned near the back of the molar row, and this suggests a separate evolutionary history and an order-level distinction. In addition, recent phylogenetic analysis suggests that creodonts are more closely related to pangolins while mesonychians might be

2214-800: The only exception, occurring in the old world and the new world, entering the Americas via the Bering Land Bridge. The caniforms include the Caninae , Procyonidae , bears , mustelids , skunks and pinnipeds that occur worldwide with immense diversity in their morphology, diet and behavior. The word carnivore is derived from Latin carō (stem carn- ) 'flesh' and vorāre 'to devour', and refers to any meat-eating organism. The oldest known carnivoran line mammals ( Carnivoramorpha ) appeared in North America 6 million years after

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2268-783: The pinnipeds, dogs, bears, hyenas, and cats all have distinct and recognizable appearances. Dogs are usually cursorial mammals and are gracile in appearance, often relying on their teeth to hold prey; bears are much larger and rely on their physical strength to forage for food. Compared to dogs and bears, cats have longer and stronger forelimbs armed with retractable claws to hold on to prey. Hyenas are dog-like feliforms that have sloping backs due to their front legs being longer than their hind legs. The raccoon family and red panda are small, bear-like carnivorans with long tails. The other small carnivoran families Nandiniidae , Prionodontidae , Viverridae , Herpestidae , Eupleridae, Mephitidae and Mustelidae have through convergent evolution maintained

2322-621: The relationships among extant and fossil bear species. One is all species of bears are classified in seven subfamilies as adopted here and related articles: Amphicynodontinae , Hemicyoninae , Ursavinae , Agriotheriinae , Ailuropodinae , Tremarctinae , and Ursinae . Below is a cladogram of the subfamilies of bears after McLellan and Reiner (1992) and Qiu et al. . (2014): † Amphicynodontinae [REDACTED] † Hemicyoninae † Ursavinae † Agriotheriinae Ailuropodinae [REDACTED] Tremarctinae [REDACTED] Ursinae [REDACTED] The second alternative phylogenetic hypothesis

2376-465: The sister group to carnivorans and their stem-relatives. The closest stem-carnivorans are the miacoids . The miacoids include the families Viverravidae and Miacidae , and together the Carnivora and Miacoidea form the stem-clade Carnivoramorpha . The miacoids were small, genet-like carnivoramorphs that occupy a variety of niches such as terrestrial and arboreal habitats. Recent studies have shown

2430-429: 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, with 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

2484-406: The small, ancestral appearance of the miacoids, though there is some variation seen such as the robust and stout physicality of badgers and the wolverine ( Gulo gulo ). Most carnivoran species have a well-defined breeding season . Male carnivorans usually have bacula , which are absent in hyenas and binturongs . The length and density of the fur vary depending on the environment that

2538-544: 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, although no fossils of this group have been found before about 11 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 (≈2.5 or 1.2 Ma) following formation of

2592-433: The species inhabits. In warm climate species, the fur is often short in length and lighter. In cold climate species, the fur is either dense or long, often with an oily substance that helps to retain heat. The pelage coloration differs between species, often including black, white, orange, yellow, red, and many shades of grey and brown. Some are striped, spotted, blotched, banded, or otherwise boldly patterned. There seems to be

2646-432: The suborder Caniformia , or "doglike" carnivorans, within the order Carnivora . Bears' closest living relatives are the pinnipeds , canids , and musteloids (some scholars formerly argued that bears are directly derived from canids and should not be classified as a separate family). Modern bears comprise eight species in three subfamilies: Ailuropodinae (monotypic with the giant panda ), Tremarctinae (monotypic with

2700-502: The support of the pinniped–amphicynodontine clade, other morphological and some molecular evidence supports bears being the closest living relatives to pinnipeds. 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. The subfamily includes the younger genera Phoberocyon (20–15 Mya), and Plithocyon (15–7 Mya). A Cephalogale -like species gave rise to

2754-527: The winter for a long period of hibernation , up to 100 days. Bears have been hunted since prehistoric times for their meat and fur; they have also been used for bear-baiting and other forms of entertainment, such as being made to dance . With their powerful physical presence, they play a prominent role in the arts , mythology , and other cultural aspects of various human societies. In modern times, bears have come under pressure through encroachment on their habitats and illegal trade in bear parts, including

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2808-653: Was best used in the Anglosphere in the 16th century but has since been rather uncommon in English-speaking countries, although its use has been influenced since the twentieth century by the Swiss-born actress Ursula Andress (born 1936). It was among the most popular names for newborn girls in Germany from the 1920s to the 1950s. Ulla , Ursel , and Uschi are German short forms of the name. Ursula

2862-494: Was implemented by McKenna et al. (1997) to classify all the bear species into the superfamily Ursoidea , with Hemicyoninae and Agriotheriinae being classified in the family "Hemicyonidae". Amphicynodontinae under this classification were classified as stem- pinnipeds in the superfamily Phocoidea . In the McKenna and Bell classification both bears and pinnipeds are in a parvorder of carnivoran mammals known as Ursida , along with

2916-486: Was not until 1821 that the English writer and traveler Thomas Edward Bowdich gave the group its modern and accepted name. Initially, the modern concept of Carnivora was divided into two suborders: the terrestrial Fissipedia and the marine Pinnipedia . Below is the classification of how the extant families were related to each other after American paleontologist George Gaylord Simpson in 1945: Since then, however,

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