Ears are attached to the head of an animal. They can be used in a variety of ways. Most cats have two ears on their head. For them, they are to determine location and movement of prey, as well as to avoid being preyed upon. They can hear sounds pulsating at 60,000 vibrations per second, while humans can hear only 20,000. Each ear can move independently to detect the direction from which a sound originates and amplify it.