“Why does a cat lick me?” was a genuine question years ago. But 15 years of the cat internet and people have learned what it means. And what it means is what it looks like: domestic cats lick their human companion (owner or guardian) because they want to do them a favour and groom them. It is called “allogrooming” in the cat world. You are likely to have seen domestic cats grooming themselves (in a strict routine) and then groom a cat friend if they happen to be lying next to them. It is an act of friendship, specifically an interspecies friendship if a human is the recipient.
If your cat is lying next to you in bed and is self-grooming (autogrooming) she might lick your hand if you place it before her. One act (grooming herself) leads to the other (grooming you). It is completely natural for a cat to do this. They are nice like that.
Occasionally it seems that there might be a different reason for it. If there is something on your hand which intrigues a cat she might sniff it and then lick it. Salty perspiration may also elicit a lick from your cat. But 90% of the time it is a simple act of friendship. The experts would describe allogrooming as part of an “affiliative relationship”. Cats are still perceived as solitary. They are no longer. They are not asocial. They may form close relationships with other cats. They can relate to humans as cats. Allogrooming is an affiliative behavior. Others are: nose touching when greeting, allorubbing and playing and resting together. You see a lot of allorubbing between cats and between cats and humans.
Every cat owner has experienced their cat rubbing their flanks against their legs when they want some food, or to be picked up or when greeting their human SO1 on their return from work. Within cat colonies they have “preferred associates” in technical language. In layperson language it means that cats have friends, mates and colleagues. It is just like the human world. It is about chemistry as to whether one cat likes another. Greater familiarity with each other leads to a greater chance of them becoming preferred associates.
When cats allogroom it is usually delivered to the head and neck, areas that the other cat can’t reach. Sometimes a cat will encourage another to groom them by approaching and lowering their head. The cat being groomed is normally highly cooperative by rotating their head to allow the groomer to reach all parts.
Allogrooming reinforces the bond of friendship as does allorubbing. Humans feel this when their cat rubs against them. It is a good feeling, right? It is mutually good. Humans stroking (petting) cats is a form of allogrooming. To the cat it is as if she is being groomed. A pet product manufacturer grabbed hold of this concept to build a plastic brush which you place in your mouth! It looks bizarre but it is based on allogrooming.
1. Significant other.
P.S. I am writing this article a second time to try and boost its prospects of being ranked higher by Google.