Instruct: Given a question, retrieve passages that can help answer the question.
Query: Is the Asian black bear the same as a Sun Bear?
Biologically and morphologically, Asiatic black bears represent the beginning of the arboreal specializations attained by sloth bears and sun bears.[3] Asiatic black bears have karyotypes nearly identical to those of the five other ursine bears, and, as is typical in the genus, they have 74 chromosomes.[15] From an evolutionary perspective, Asiatic black bears are the least changed of Old World bears, with certain scientists arguing that it is likely that all other lineages of ursine bear stem from this species.[2] Scientists have proposed that Asiatic black bears are either a surviving, albeit modified, form of Ursus etruscus, specifically the early, small variety of the Middle Villafranchian (Upper Pliocene to Lower Pleistocene)[16] or a larger form of Ursus minimus, an extinct species that arose 4,000,000 years ago. With the exception of the age of the bones, it is often difficult to distinguish the remains of Ursus minimus with those of modern Asiatic black bears.[2]
An American black bear has better eyesight and a better sense of hearing compared to humans. Their keenest sense is their sense of smell, which is about seven times greater than a domestic dog's. American black bears are excellent and strong swimmers, doing so for pleasure and to feed (largely on fish). They regularly climb trees to feed, escape enemies and hibernate. Four of the eight modern bear species are habitually arboreal (the most arboreal species, the American and Asian black bears and the sun bear, being fairly closely related). Their arboreal abilities tend to decline with age. American black bears may be active at any time of the day or night, although they mainly forage by night. American black bears living near human habitations tend to be more extensively nocturnal and American black bears living near brown bears tend to be more extensively diurnal. Their social behavior is somewhat similar to that of canids.
The Asiatic black bear's range overlaps with that of sloth bears in central and southern India, sun bears in Southeast Asia and brown bears in the southern part of the Russian Far East.[37] Ussuri brown bears may attack black bears,[28] though Himalayan brown bears seem to be intimidated by the black species in direct encounters.[38] They will eat the fruit dropped by black bears from trees, as they themselves are too large and cumbersome to climb.[38][39]
Although mostly herbivorous, the jaw structure of Asiatic black bears is not as specialized for plant eating as that of pandas: Asian black bears have much narrower zygomatic arches, and the weight ratio of the two pterygoid muscles is also much smaller in Asian black bears. The lateral slips of the temporal muscles are thicker and stronger in black bears.[7]
Brown bears usually dominate other bear species in areas where they coexist. Due to their smaller size, American black bears are at a competitive disadvantage to brown bears in open, unforested areas. Although displacement of American black bears by brown bears has been documented, actual interspecific killing of American black bears by brown bears has only occasionally been reported. Confrontation is mostly avoided due to the American black bear's diurnal habits and preference for heavily forested areas, as opposed to the brown bear's largely nocturnal habits and preference for open spaces. Where they do not live in close proximity to grizzly bears, and especially where found near human habitations, American black bears may become, to a larger extent, nocturnal. Brown bears may also kill Asian black bears, though the latter species probably largely avoids conflicts with the brown bear due to similar habits and habitat preferences to the American black species. Brown bears will eat the fruit dropped from trees by the Asian black bear, as they themselves are too large and cumbersome to climb. Improbably, in the Himalayas, brown bears are reportedly intimidated by Asian black bears in confrontations. However, the Himalayan black bears are reportedly more aggressive towards humans than the Himalayan brown bear, and the latter is one of the smaller types of brown bear, though still somewhat larger than the Asian black bear. In Siberia, the opposite is true, and Asian black bears are not known to attack people, but brown bears are. Both species of black bear seem to be most vulnerable to predatory attacks by brown bears when the latter species leaves hibernation sooner in early spring and ambushes the smaller ursids in their dens.
The ancestors of American black bears and Asian black bears diverged from sun bears 4.58 mya. The American black bear then split from the Asian black bear 4.08 mya. The earliest American black bear fossils, which were located in Port Kennedy, Pennsylvania, greatly resemble the Asian species, though later specimens grew to sizes comparable to grizzly bears. From the Holocene to the present, American black bears seem to have shrunk in size, but this has been disputed because of problems with dating these fossil specimens.
Along with sun bears, Asiatic black bears are the most typically used species in areas where bears are either used in performances or as pets.[67] Asian black bears have an outstanding learning ability in captivity, and are among the most common species used in circus acts.[68] According to Gary Brown:
Asiatic black bears are reproductively compatible with several other bear species, and have on occasion produced hybrid offspring. According to Jack Hanna's Monkeys on the Interstate, a bear captured in Sanford, Florida was thought to have been the offspring of an escaped female Asiatic black bear and a male American black bear, and Scherren's Some notes on hybrid bears published in 1907 mentioned a successful mating between an Asiatic black bear and a sloth bear.[23] In 1975, within Venezuela's "Las Delicias" Zoo, a female black bear shared its enclosure with a male spectacled bear, and produced several hybrid descendants.[24] In 2005, a possible black bear–sun bear hybrid cub was captured in the Mekong River watershed of eastern Cambodia.[25] An Asiatic black bear/brown bear hybrid, taken from a bile farm, is housed at the Animals Asia Foundation's China Moon Bear Rescue as of 2010.[26]
The Malayan sun bear (H. m. malayanus (Raffles, 1821)) occurs on the Asian mainland and Sumatra.[11] The Bornean sun bear (H. m. euryspilus (Horsfield, 1825)) occurs only on the island of Borneo.[12]
A recent study found genetic evidence of multiple instances and species combinations where genetic material has passed the species boundary in bears (a process called introgression by geneticists). Specifically, species with evidence of past intermingling were (1) brown bear and American black bear, (2) brown bear and polar bear, (3) American black bear and Asian black bear, (4) bears currently distributed in Asia (sloth bear, sun bear and Asian black bear). Overall, this study shows that evolution in the bear family (Ursidae) has not been strictly bifurcating, but instead showed complex evolutionary relationships.
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").
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 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 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 the brown bear around 400,000 years ago.
Despite living in North America, American black bears are not closely related to brown bears and polar bears; genetic studies reveal that they split from a common ancestor 5.05 million years ago (mya). American and Asian black bears are considered sister taxa and are more closely related to each other than to the other modern species of bears. According to recent studies, the sun bear is also a relatively recent split from this lineage.
Although black bears have been afforded protection in Russia since 1983, illegal poaching, fuelled by a growing demand for bear parts in the Asian market, is still a major threat to the Russian population. Many workers of Chinese and Korean origin, supposedly employed in the timber industry, are actually involved in the illegal trade. Some Russian sailors reportedly purchase bear parts from local hunters to sell them to Japanese and Southeast Asian clients. Russia's rapidly growing timber industry has been a serious threat to the Asiatic black bear's home range for three decades. The cutting of trees containing cavities deprives black bears of their main source of dens, and forces them to den on the ground or in rocks, thus making them more vulnerable to tigers, brown bears and hunters.[15]
Within Sikhote-Alin, the breeding season of black bears occurs earlier than in brown bears, starting from mid June to mid August. Birth also occurs earlier, in mid January. By October, the uterine horns of pregnant females grow to 15–22 millimetres (0.59–0.87in). By late December, the embryos weigh 75grams.[3] Sows generally have their first litter at the age of three years.[15] Pregnant females generally make up 14% of populations. Similar to brown bears, Asiatic black bears have delayed implantation.[15] Sows usually give birth in caves or hollow trees in winter or early spring after a gestation period of 200–240 days. Cubs weigh 13 ounces at birth, and will begin walking at four days of age, and open their eyes three days later.[27] The skulls of newborn black bear cubs bear great resemblance to those of adult sun bears.[3] Litters can consist of 1–4 cubs, with 2 being the average.[27] Cubs have a slow growth rate, reaching only 2.5kg by May.[3] Black bear cubs will nurse for 104–130 weeks, and become independent at 24–36 months. There is usually a 2–3 year interval period before females produce subsequent litters.[27] The average lifespan in the wild is 25 years, while the oldest Asian black bear in captivity died at the age of 44.[4]
The American black bear lived during the same period as the giant and lesser short-faced bears ("Arctodus simus" and "A. pristinus", respectively) and the Florida spectacled bear ("Tremarctos floridanus"). These tremarctine bears evolved from bears that had emigrated from Asia to North America 7–8 ma. The giant and lesser short-faced bears are thought to have been heavily carnivorous and the Florida spectacled bear more herbivorous, while the American black bears remained arboreal omnivores, like their Asian ancestors. The American black bear's generalist behavior allowed it to exploit a wider variety of foods and has been given as a reason why, of these three genera, it alone survived climate and vegetative changes through the last Ice Age while the other, more specialized North American predators became extinct. However, both "Arctodus" and "Tremarctos" had survived several other, previous ice ages. After these prehistoric ursids became extinct during the last glacial period 10,000 years ago, American black bears were probably the only bear present in much of North America until the migration of brown bears to the rest of the continent.
Asiatic black bears are close relatives to American black bears, with which they share a European common ancestor;[17] the two species are thought to have diverged 3,000,000 years ago, though genetic evidence is inconclusive. Both American and Asiatic species are considered sister taxa and are more closely related to each other than other species of bear.[18] The earliest American black bear fossils, which were located in Port Kennedy, Pennsylvania, greatly resemble the Asiatic species.[16] The first mtDNA study undertaken on Asiatic black bears suggested that the species arose after the American black bears, while a second study could not statistically resolve the branching order of sloth bears and the two black species, suggesting that these three species underwent a rapid radiation event. A third study suggested that American black bears and Asiatic black bears diverged as sister taxa after the sloth bear lineage and before the sun bear lineage.[15] Further investigations on the entire mitochondrial cytochrome b sequence indicate that the divergence of continental and Japanese black bear populations might have occurred when bears crossed the land bridge between the Korean peninsula and Japan 500,000 years ago, which is consistent with paleontological evidence.[19]
The species is morphologically very similar to some prehistoric bears, and is thought by some scientists to be the ancestor of other extant bear species (aside from pandas and spectacled bears).[2] Although largely herbivorous, Asian black bears can be very aggressive toward humans, who frequently trap or kill them for traditional medicine.[4]
Today, black bears are only legally hunted for sport in Japan and Russia. In Russia, 75–100 black bears are legally harvested annually, though 500 a year are reportedly harvested illegally.[1] Russian sport hunting of black bears became legalised in 2004. According to a 2008 article written in The Sun, Russia's Slavic Hunting Club offers four day trips with four guaranteed black bear kills for the sum of £16,000. The article indicated that clients receiving permits for black bear hunts included people from Britain, the United States, Germany, Spain, Poland and Finland.[70] After the introduction of Buddhism in Japan, which prohibited the killing of animals, the Japanese compromised by devising different strategies in hunting bears. Some, such as the inhabitants of the Kiso area in the Nagano Prefecture, prohibited the practise altogether, while others developed rituals in order to placate the spirits of killed bears. In some Japanese hunting communities, black bears lacking the white chest mark are considered sacred. In the Akita Prefecture, bears lacking the mark were known by matagi huntsmen as minaguro (all black) or munaguro (black chested), and were also considered messengers of yama no kami. If such a bear was shot, the huntsman would offer it to yama no kami, and give up hunting from that time on. Similar beliefs were held in Nagano, where the completely black bears were termed nekoguma or cat-bear. Matagi communities believed that killing a bear in the mountains would result in a bad storm, which was linked to the belief that bear spirits could affect weather. The matagi would generally hunt bears in spring or from late autumn to early winter, before they hibernated. In mountain regions, bears were hunted by driving them upland to a waiting hunter who would shoot it. Bear hunting expeditions were preceded by rituals, and could last up to two weeks. After killing the bear, the matagi would pray for the bear's soul.[10] Bear hunts in Japan are often termed kuma taiji, meaning "bear conquest". The word taiji itself is often used in Japanese folklore to describe the slaying of monsters and demons.[50]
The area has a high level of biodiversity, and a number of endangered species including tiger, leopard, clouded leopard, Asian golden cat, marbled cat, civet, gaur, Sambar deer, white-cheeked gibbon, sun bear, black bear, Asian elephant, dhole, hornbill and three species of otter.
The Japanese black bear ("Ursus thibetanus japonicus") is a subspecies of the Asian black bear that lives on three main islands of Japan: Honshu, Shikoku and Kyushu. There are said to be 10,000 black bears on Japan. The population of black bears on Shikoku and Kyushu may be endangered or extinct. There is a high price on bear parts in the black market, which threatens all bear populations in Japan. This particular species of bear are typically smaller with males only reaching and females only weighing about . Their body length is about long.
There are a number of large mammals in Laos, including the Asian elephant ("Elephas maximus") and Indochinese tiger ("Panthera tigris corbetti"). There are two species of bear, the sun bear ("Helarctos malayanus") and Asian black bear ("Ursus thibetanus"). Smaller carnovorans include the leopard cat ("Prionailurus bengalensis"), marbled cat ("Pardofelis marmorata") and hog badger ("Arctonyx collaris").
Sloth bear fur is completely black (rusty for some specimens), save for a whitish Y- or V-shaped mark on the chest. This feature is sometimes absent, particularly in Sri Lankan specimens. This feature, which is also present in Asian black bears and sun bears, is thought to serve as a threat display, as all three species are sympatric with tigers (tigers usually do not carry out attacks on an adult bear if the bear is aware or facing the cat). The coat is long, shaggy, and unkempt, despite the relatively warm environment in which the species is found, and is particularly heavy behind the neck and between the shoulders, forming a mane which can be long. The belly and underlegs can be almost bare. Sloth bears are usually about the same size as an Asian black bear but are immediately distinctive for their shaggier coat, whitish claws, as well as their typically rangier build. Their head and mouth is highly distinct from that of a black bear with a longer, narrower skull shape (particularly the snout), loose-looking, flappier lips and paler muzzle colour. In few areas of overlap, sloth bear confusion with sun bears is unlikely, given the latter species considerably smaller size, much shorter fur, wrinkled folding skin (especially around the back), bolder chest marking and drastically different, more compact head structure and appearance.
In 2005, a possible black bear/sun bear hybrid cub was captured in the Mekong River watershed of eastern Cambodia. The hybrid's mane was relatively slight, forming a crest on each side of the neck, as is typical in sun bears and some black bears. The appearance of its face was intermediate between that of the sun bear and the black bear, though its ears and large stout canines closely resembled those of the sun bear. Overall, the hybrid resembled an Asiatic black bear with an unusually glossy pelage and an unusual head.
American black bears feature prominently in the stories of some of America's indigenous peoples. One tale tells of how the black bear was a creation of the Great Spirit, while the grizzly bear was created by the Evil Spirit. In the mythology of the Haida, Tlingit and Tsimshian people of the Northwest Coast, mankind first learned to respect bears when a girl married the son of a black bear chieftain. In Kwakiutl mythology, American black and brown bears became enemies when Grizzly Bear Woman killed Black Bear Woman for being lazy. Black Bear Woman's children, in turn, killed Grizzly Bear Woman's children. The Navajo believed that the Big Black Bear was chief among the bears of the four directions surrounding Sun's house and would pray to it in order to be granted its protection during raids.
Following a decrease of ungulate populations from 1944 to 1959, more than 32 cases of Amur tigers attacking both brown and Asian black bears were recorded in the Russian Far East, and hair of bears were found in several tiger scat samples. Tigers attack Asian black bears less often than brown bears, as latter live in more open habitat and are not able to climb trees. In the same time period, four cases of brown bears killing female and young tigers were reported, both in disputes over prey and in self-defense. Tigers can tackle bears larger than themselves, using an ambushing tactic and jumping onto the bear from an overhead position, grabbing it by the chin with one fore paw and by the throat with the other, and then killing it with a bite in the spinal column. Tigers mainly feed on the bear's fat deposits, such as the back, hams, and groin.