The feline mystique is what keeps cats so well-loved while at the same time being so misunderstood. Why cats do the things they do is the subject of learned anthropologists and average cat lovers alike. Some of the things they do make sense in the wild, such as head-butting.
In order to truly understand some of the things cats do, you need to look at two things: feline anatomy and ancestral habits, because they truly do go paw in paw. Legendary comedian Johnny Carson once told a story about how his cat rubbed against his leg and he thought, "Wow, my cat loves me." But then the cat rubbed against the table and the chair too, so he thought, "I guess he really loves the furniture too!" Carson's cat was doing what millions of cats do -- marking his territory. Cats have scent glands that secret pheromones all over their bodies, including their foreheads and cheeks. When your cat head-butts you, he is laying this odorless (to you) pheromone onto you.
When your cat sniffs you, she can smell everything you have been in contact with all day. She smells the neighbor's dog on your shoes, or the tuna you had for lunch. She knows more about you than you can ever know about her. Because cats have such a highly evolved sense of smell, they assume everyone has this talent. So they mark the things they want to claim as their own, such as their person. Spend some time watching your pet and you'll notice he'll not only head-butt you, but also your furniture, walls, his scratching post and anywhere else he wants to claim as his own. Some cats will even head-butt the family dog! They also head-butt one another. These are all ways of claiming what they believe is theirs.
So pheromones play a big part in this little display of "whats yours is mine and what's mine is mine," but what exactly are they? Pheromones are hormones that are outside the body. They are secreted by animals and insects. The reason humans cannot smell them is that they can only be detected through the vomeronasal organ, which humans have not developed. Pheromones are used to communicate with other animals and to manipulate those animals into doing a specific activity such as laying eggs, bonding baby to mother, marking territory and preparing for sexual activity.
When people attribute human qualities to animals or explain animal behavior in human terms, it's called anthropomorphism. Examples of this are statements such as, "The dog knew shredding my shoes was bad, that's why he looked guilty" or "My cat adores me so much, that's why she lays on my lap and purrs." In truth, dogs cannot feel guilt, and cats lay on laps because the lap is soft and warm. If your cat is head-butting and rubbing against you (secreting pheromones from other parts of the body in the process), you can tell yourself she is showing affection. After all, you are HER person.
Michelle A. Rivera is the author of many books and articles. She attended the University of Missouri Animal Cruelty School and is certified with the Florida Animal Control Association. She is the executive director of her own nonprofit, Animals 101, Inc. Rivera is an animal-assisted therapist, humane educator, former shelter manager, rescue volunteer coordinator, dog trainer and veterinary technician.