Cat Licking Isn't Always Friendly: New Study Reveals Aggressive Allogrooming

A new study published in Applied Animal Behaviour Science in May reveals that when cats lick each other (allogrooming), it is not always a friendly gesture. The research, led by veterinarian Morgane Van Belle at Ghent University, analyzed videos from 53 two-cat households and identified two main contexts: social bonding and social tension. In friendly contexts, grooming often occurs on the head or ears, and 41% of snuggle occasions were followed by allogrooming. However, in tense situations—such as when one cat wants a sunny spot occupied by another—allogrooming on the neck can be a subtle form of aggression, causing the recipient to flatten its ears, bite, or scratch. The study also noted stress indicators like headshaking, lip licking, yawning, and scratching behind the ears, especially when cats were not in the same position. Van Belle describes this as an elegant conflict resolution method, showing cats are intelligent and flexible. Veterinary behaviorist Ashley Elzerman of Zoetis praised the empirical work for increasing understanding of cat social dynamics in multicat households.