Researchers at Ghent University examined 106 video clips of cat pairs from 53 households to understand the motivations behind allogrooming. Their findings show that licking is not solely a sign of affection.
In some instances, licking acts as a subtle warning signal when one cat is annoyed by another’s behavior, such as stealing a sunny spot. This passive‑aggressive pattern may be accompanied by flattened ears, head shaking, or light biting and aims to defuse tension without an outright fight.
Conversely, the same behavior can be used as an appeasement gesture to prevent a looming confrontation. One cat may lick another to restore peace, akin to a calming gesture in human interaction.
Another observed pattern involves one cat leaning over the other while licking, which can be interpreted as intimidation or bullying. The recipient often shows displeasure through ear position or avoidance.
Approximately 87 % of licking episodes focus on the head and neck—areas cats struggle to reach themselves but find pleasurable. Mutual grooming also strengthens social bonds, especially when the cats have previously played or display synchronized postures. Finally, licking can have a relaxing effect, lowering the recipient’s heart rate and triggering the release of beta‑endorphins.
The scientists suggest that a nuanced understanding of these behaviors can help owners identify and reduce stress in multi‑cat homes. Further research is needed to confirm the identified functions and possibly uncover additional aspects.