Collisions Between Feline and Human Worlds
In some ways, the cat's natural behavior matches the life style of many families. The home is empty for much of the day, and that suits the cat because it has the genetic makeup and behavioral instincts to be a loner. But living with a pet cat may also bring us into confrontation with some behaviors that are normal for the wild cat, but which can be quite undesirable in our homes. For example, scratching one or two tree trunks outdoors is perfectly normal behavior for a wild cat. One function of scratching is to remove the worn outer layer of the claw, exposing a new claw underneath. This behavior also enables cats in the wild to mark their territories. A cat will scratch one or more trees or other prominent areas, and in the process of scratching, rub secretions from its feet onto the tree trunk. This gives the scratched area a distinct odor that other cats in the territory recognize. To maintain its territorial marker, the cat repeatedly scratches and freshens the visual and chemical marks.
Pet cats have the same instinctual response to mark a territory. Just as an outdoor cat chooses a prominent tree, an indoor cat chooses a prominent object, such as a couch or chair. The domestic cat also freshens its marker by repeatedly scratching it. But, a domestic cat that scratches furniture or drapes can prove costly to the cat's owner.

