Ursus is a genus of mammals that includes bears, which are large, powerful animals found in various habitats around the world. There are eight species of bears, including the American black bear, grizzly bear, and polar bear. Bears are known for their thick fur, strong limbs, and keen sense of smell. Bears are omnivorous, meaning they eat both plants and animals. Their diet can include fruits, nuts, insects, and fish. They are typically solitary creatures, except for mothers with cubs or during mating season. Bears hibernate in winter, entering a state of reduced metabolic activity to conserve energy.