The scratching post

Cats scratch to peel away the dead surface of their nails, to keep their nails sharp, for exercise, and according to some animal behaviorists, to mark their territory.  Some surfaces tend to become favorite scratching areas and "smell signals" from the kitten's footpads reinforce the use of these areas.  This is why a kitten should be introduced to a scratching post as it has become adjusted to its new surroundings.

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