Bears have heavy bodies supporting a large, hairy head. Their thick fur covers a loose skin covering. They have small eyes and poor eyesight. Small, rounded ears stick straight up, but a bear's hearing is only fair. Bears do have a keen sense of smell. They have short, powerful limbs with large feet. A bear's foot has five toes, and each toe ends with a long, heavy claw. The strong claws are used to dig up roots, turn over large boulders, and tear into rotting timber looking for ants, termites, and other food. Bears, like a human, walk putting their entire foot sole on the ground with each step, and their heel strikes down first. This walk is different that most other animals that walk and run on their toes. Combining this gait with their large feet and short legs sometimes makes a bear look slow and ungainly. However, bears are extremely agile and can move quickly, running at speeds well over 30 miles an hour.