There are 9 species of bears , which occur on every continent except Australia and Antarctica. They are most diverse and abundant in the northern hemisphere, including North America and Eurasia. Bear species range in size from small (red panda, 3 to 5 kg) to very large (polar bear, 800 kg), but most are medium to large-sized mammals. They are powerfully built with thick hair that is black, brown, or white. They have small, rounded ears, small eyes, and short tails.
Bear species are omnivorous; they eat both plant and animal foods as they are available. Even some of the largest species, such as grizzly bears, rely mainly on insects, fruit, and nuts during parts of the year. They have an excellent sense of smell but their eyesight and hearing are limited. Bears usually live on their own. They tend to move slowly through their territories in search of food and mates but are capable of running quickly, climbing, and swimming. In colder regions bears put on fat during the fall and enter a dormant period during the coldest months. This is not a true form of hibernation because their body temperatures dont decrease and they will wake up readily if disturbed.
Bears are found in a wide range of habitats, from tropical forests to tundra.