The head is large compared with the rest of the body. The nose and jaws are short, so the face seems flat when compared with the faces of many other kinds of mammals such as dogs, horses, and rodents. The triangular ears taper to rounded or pointed tips and stand erect in almost all breeds. A cat has keen hearing and can detect many sounds that humans cannot hear. A cat usually turns its head, not only its eyes, in the direction of a sound. This aids both hearing and vision. In the cat, as in humans, the inner ear—a bony structure of fluid-filled semicircular canals—contains a complicated mechanism for maintaining body balance. It is this mechanism, not the cat's tail, that enables the animal to land on its feet when it falls.
The cat's large and prominent eyes are placed well forward on the head and, like the eyes of humans, they face forward. The cat comes closer than does any other animal except owls and apes to having binocular vision similar to that of humans.
The size and position of the eyes permit as much light as possible to enter them and ensure an extensive field of vision—important factors in hunting and nocturnal prowling. A cat cannot see in total darkness, but it can see better in dim light than can most other kinds of animals.
Art:The pupils of a cat's eyes expand or contract in response to the amount of light.
The pupils of a cat's eyes expand or contract in response to the amount of light.
Encyclopædia Britannica, Inc.
In bright light a cat's pupils contract to narrow vertical slits. But in the dark these slits enlarge to round openings that admit a maximum amount of light. The eyes seem to shine in the dark. This effect results from even the smallest amount of light striking a reflective layer of iridescent green or yellow crystalline needles lining the back of the eye. The eyes of the Siamese cat appear red in the dark, as the retinas lack pigment, and the color is provided by blood vessels. A cat is very alert to any movement, but it probably cannot distinguish color. For these reasons, it will pounce when a victim moves but may not attack prey that remains still.
The tip of a cat's nose, the leather, may be black, reddish, or pink and is usually cool and moist. All cats have an acute sense of smell and can detect prey or their favorite delicacies at surprising distances.
A cat's whiskers, or vibrissae, serve as delicate sense organs of touch. Four rows of stiff whiskers grow on the upper lip on each side of the nose. Small groups of whiskers also are situated on other parts of the body including above each eye, on both cheeks, and on the backs of the forepaws. Cutting off the whiskers not only detracts from the animal's appearance but also impairs its ability to feel its way about.
A cat's teeth serve primarily as weapons, as well as for tearing food. The animal has 30 permanent teeth. The strongest and sharpest are the four large, curved, pointed fangs (canines). With these teeth the cat grasps and tears its food or an enemy. The small front teeth (upper and lower incisors) function chiefly as grooming aids. The cat has fewer side teeth (premolars and molars) than do most other mammals. In most mammals the side teeth are used for grinding food. The cat uses these teeth only for cutting.
Art:Rasplike barbs on the surface of a cat's tongue help it lap up liquids and groom itself.
Rasplike barbs on the surface of a cat's tongue help it lap up liquids and groom itself.
Encyclopædia Britannica, Inc.
A cat's tongue is rough. The tongue of a domestic cat feels much like coarse sandpaper. The tongue of a big wild cat, such as the lion or the tiger, is even rougher. The tongue surface is covered with rasplike projections or barbs that face backward into the throat. All cats use their tongues to clean and comb the fur, and they also use them as efficient tools to strip flesh off the bones of prey.
Although a cat's jaws are short, they are extremely strong. They clamp down upon prey with enough power to crush the bones. The lower jaw is attached to the upper one by means of a simple hinge. This arrangement permits only up-and-down motion. A cat cannot move its lower jaw sideways, nor can it grind its teeth. When a cat clamps its jaws shut, the teeth mesh side by side and function like scissors. Cats thus tear and crush their food but do not chew it. Much of the food is swallowed whole, and digestive juices break it down further.
Video:Purring is characteristic of domestic cats and other small cat species.
Purring is characteristic of domestic cats and other small cat species.
Contunico © ZDF Enterprises GmbH, Mainz
All cats—domestic and wild—can and do purr. The sound may be very loud or so soft as to be inaudible to the human ear. Kittens may begin to purr a few days after birth. In all animals, vocal sounds come from vibrations of the vocal cords, which are in the voice box in the throat. No one knows exactly how the cat uses these to produce purring nor why no other ki