Lately, I've been noticing that Callie licks everything. She of course gives me lots of kisses, and is much given to licking my sleeve or pants leg. Now, she's licking the edge of the coffee table, which I can stretch into making sense as I frequently use the coffee table as my dining room table. However, last night I saw her systematically lick each one of the pulls on my bathroom drawers and cabinets (12 in all). Why? Why has she been licking picture frames on my bookshelves? The walls? It is baffling to me. Is this a kind of "marking" behavior? Any thoughts?