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Wild Animals - Bears
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 which are now placed at subgenus rank. A number of hybrids have been bred between American black, brown, and polar bears (see Ursid hybrids). Bears are generally bulky and robust animals with relatively short legs. Bears 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 members of the order Carnivora, with some Polar Bears and Brown Bears weighing over 750 kilograms (1,700 lb). As to which species is the largest may depend on whether the assessment is based on which species has the largest individuals (brown bears) or on the largest average size (polar bears). The smallest bears are the Sun
Biology
Morphology
Bears of Asia, which weigh an average of 65 kilograms (140 lb) for the males and 45 kilograms (99 lb) for the females. Unlike other land carnivorans, bears are plantigrade. They distribute their weight toward the hind feet which makes then look lumbering when they walk. They are still quite fast with the brown bear reaching 30 miles per hour (48 km/h) although they are still slower than felines and canines. Bears can stand on their hind feet and sit up straight with remarkable balance. Bears have non-retractable claws which are used for digging, climbing, tearing and catching prey. Their ears are rounded. Bears have an excellent sense of smell, a better sense of smell in fact 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 diet. 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. There is considerable variation in dental formula even within a given species. It has been