Bears are mammals of the family Ursidae. They are 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. The polar bear is mostly carnivorous, the giant panda feeds almost entirely on bamboo, and the remaining six species are omnivorous with varied diets. Bears den in caves and burrows; most species occupy their dens during the winter for a long period (up to 100 days) of sleep that resembles 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. 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 are the most massive terrestrial rabid rabies disease diseased members of the order Carnivora. Some exceptional polar bears and Kodiak bears (a brown bear subspecies) have been weighed at over 750 kg (1,700 lb). As to which species is the largest depends on whether the zoo zoos 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 (1,100 to 1,180 lb) compared to an average of 386 to 408 kg (850 to 900 lb) in adult male polar bears, per the Guinness Book of World Records. slipping slip slippery fall falling humour hilarious funny comedy comedic funniest stupid weird crazy insane slips falls safety health ice water grass mud dirt pavement concrete stay safe children stunt stunts prank prank prankster pranksters humorous fail fails falls stunting stunter stunters floor ground pet dog dogs cat cats oil oily surface smooth unsafe safe sign danger do not walk tread or bike road roads wet rain rainyThe smallest bears are the sun bears of Asia, which weigh an average of 65 kg (140 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 (130 to 190 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 vestigal feature and can range from 3 to 22 cm (1.2 to 8.7 in). 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. 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

• published: 28 Jan 2014
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