32-454: † Amphicyoninae † Daphoeninae † Haplocyoninae † Temnocyoninae † Thaumastocyoninae Amphicyonidae is an extinct family of terrestrial carnivorans belonging to the suborder Caniformia . They first appeared in North America in the middle Eocene (around 45 mya), spread to Europe by the late Eocene (35 mya), and further spread to Asia and Africa by the early Miocene (23 mya). They had largely disappeared worldwide by
64-472: A digitigrade posture and locomotion (walking on their toes), while many of the later and larger species were plantigrade or semiplantigrade. The amphicyonids were obligate carnivores , unlike the Canidae, which are hypercarnivores or mesocarnivores . There is often some confusion with the similar looking (and similarly named) "dog-bears", a more derived group of caniforms that is sometimes classified as
96-611: A family ( Hemicyonidae ), but is more often considered a primitive subfamily of ursids ( Hemicyoninae ). It has long been uncertain where amphicyonids originated. It was thought that they may have crossed from Europe to North America during the Miocene epoch, but recent research suggests a possible North American origin from the miacids Miacis cognitus and M. australis (now renamed as the genera Gustafsonia and Angelarctocyon , respectively). As these are of North American origin, but appear to be early amphicyonids, it may be that
128-561: A family of names for 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"
160-678: 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 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
192-483: Is a stub . You can help Misplaced Pages by expanding it . Ursidae 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
224-562: Is a subfamily of extinct amphicyonids , large terrestrial carnivores sometimes called "bear-dogs", belonging to the suborder Caniformia , which inhabited North America , Eurasia , and Africa from the middle Eocene to the late Miocene . Amphicyoninae was first named by Trouessart (1885). It was assigned to Canidae by Matthew (1902), to Ursidae by Ginsburg (1977) and to Amphicyonidae by Hunt (1998). Genera include: Specimens have been recovered from: This article related to prehistoric animals from order Carnivora
256-452: Is classically named Arctamphicyon lydekkeri , which may actually be synonymous with a species of Amphicyon . Fossils of juvenile Agnotherium , Ischyrocyon , and Magericyon all show an unusual type of tooth eruption in which there is a vulnerable stage at about two or three years of age where the subadult animal has no functional molar or carnassial teeth, the only functional cheek teeth being several milk premolars. This period
288-462: 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
320-648: 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
352-646: 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
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#1732787451051384-399: 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
416-553: The Amphicyonidae actually originates in North America. Other New World amphicyonids include the oldest known amphicyonid, Daphoenus (37–16 Mya). Amphicyonids began to decline in the late Miocene, and disappeared by the end of the epoch. The exact reasons for this are unclear. The most recent known amphicyonid remains are teeth known from the Dhok Pathan horizon, northern Pakistan , dating to 7.4-5.3 mya. The species
448-537: 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 the polar bear is mostly carnivorous , and the giant panda is mostly herbivorous , the remaining six species are omnivorous with varying diets. With
480-507: 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,
512-760: 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
544-521: 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
576-526: 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
608-674: 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 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
640-664: The family Canidae , but the modern consensus is that they form their own family. Some researchers have defined it as the sister clade to ursids ( bears ), based on morphological analysis of the ear region. However, cladistic analysis and reclassification of several species of early carnivore as amphicyonids has strongly suggested that they may be basal caniforms, from lineages older than the origin of both bears and dogs. Amphicyonids ranged in size from as small as 5 kg (11 lb) and as large as 100 to 773 kg (220 to 1,704 lb) and evolved from wolf-like to bear-like body forms. Early amphicyonids, such as Daphoenodon , possessed
672-571: 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
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#1732787451051704-458: 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
736-511: The late Miocene (5 mya), with the latest recorded species at the end of the Miocene in Africa. They were among the first carnivorans to evolve large body size. Amphicyonids are colloquially referred to as " bear-dogs ". The family was erected by Haeckel in 1866 (also attributed to Trouessart 1885). Their exact position has long been disputed. Some early paleontologists defined them as members of
768-659: 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
800-418: 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
832-628: 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
864-485: 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
896-547: 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
928-434: 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
960-509: 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
992-496: 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
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1024-602: Was suggested to be "presumably short" but would have made it very difficult for the animal to process food. This type of tooth replacement is not seen in similar carnivorans like ursids or canids , and may have been one factor in the extinction of the Amphicyonidae. Family Amphicyonidae Amphicyoninae † Amphicyon † Bonisicyon † Cynelos † Cynodictis † Goupilictis † Ischyrocyon † Magericyon † Mogharacyon † Myacyon † Namibiocyon † Paludocyon † Peignecyon † Pliocyon † Pseudocyon † Tartarocyon Amphicyoninae
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