The teeth grow throughout life, cheek teeth (molars and premolars) can grow up to 1/16 inch (1.5 mm) a week. It’s easy to calculate how long the teeth would be after two years if they weren’t worn down by chewing on hard materials like twigs.
The tongue performs many functions. It is used for eating, helps with swallowing and grooming, and has an impressive number of taste buds. Guinea pigs prefer foods that are slightly but not too sweet. They don’t like bitter foods.
Each front foot has four toes and each hind foot has three. Guinea pigs have sweat glands and sebaceous glands on the pads of their feet. They must be able to wear down their toenails on a hard floor. Overgrown nails should be trimmed, preferably by a veterinarian, because they can cause pain when the animal walks.
Wild cavies have an inconspicuous grayish brown coat of hair. This is important in the wild so that the animals avoid attracting the attention of their numerous enemies. Our modern domestic guinea pigs, on the other hand, have coats that come in many different colors, lengths, and textures.
The eyes are on either side of the head. Advantage: enemies can nor approach unnoticed from behind. The price for this: Depth perception is not very good. Guinea pigs probably see colors as well as we do.
Smell plays a major role in a guinea pig’s life. It helps the animal communicate and identify others of his kind. A guinea pig learns to recognize you by your personal scent, which is why your hand shouldn’t smell like perfume, cleaning products, or your dogs. Tactile hairs (whiskers), arranged around the mouth, are especially useful in the dark. They help the guinea pig find his way. When the tactile hairs brush against an object, this gives the animal needed information.
Guinea pig hears very well. They recognize each other by individual sounds and communicate by cooing and chattering. The animals are especially sensitive to high-frequency noise.