Sometimes it’s hard to know if our favorite felines are playing rough-and-tumble games or if they’re actually fighting. To find out, and because there’s little scientific evidence to solve this mystery, researchers set out to investigate these interactions.

Your cat might be cute, full of cuddles and purring with you. But as soon as your pet crosses paths with another feline, it might seem to take on another personality. Sometimes, it can be hard to tell whether these interactions with other cats are playful, social encounters, or if the cats are actually fighting, to mark their territory, for example.

To help pet owners try to understand these interactions, researchers in Slovakia conducted a study, recently published in the journal Scientific Reports. “We found out that there was actually very little scientific evidence to guide us in answering this question, so we decided to go for it and study inter-cat interactions,” said the study’s first author, Noema Gajdoš‑Kmecová, of the University of Veterinary Medicine and Pharmacy, in Košice, Slovakia, speaking to The Guardian.

Noema Gajdoš-Kmecová and colleagues carefully analyzed 105 videos found on YouTube featuring interactions between various cats (210 felines in total). Based on these images, as well as feedback from several cat owners, the team of scientists listed several distinctive elements that allow them to determine if a cat is looking to play or is out for a fight.

Listen carefully to the noises cats are making

The study was based on the frequency and duration of six distinctive cat behavioral categories (noises, postures, tail and paw gestures, etc.). And according to the observations made during this research, the most revealing category in determining whether two cats are playing or fighting is the noise level. “When cats are young and when they are wrestling and not vocalizing, they are most likely playing,” the researchers suggest in their paper.

On the other hand, chasing, prolonged motionless postures or getting their claws out were actions identified as behaviors that suggest aggressive interactions rather than playfulness. The authors of the study specify, however, that felines are likely to switch between playing and fighting, and that there is also an intermediate state between these two attitudes.

“It is important to recognize that interactions may differ from day to day or even from one occasion within a day to the other, as proximate needs and wants vary. Thus, a single incident does not predict the relationship,” explain the researchers. So don’t panic if you’ve got two cats in the house that seem to bicker. Just keep an eye out, an ear open and carefully observe the situation!