There are many animals that enjoy the act of playing as a way of both learning and exploring the world. This list includes many forms of life, such as monkeys, dolphins and human beings. However, that list just got bigger due to a recent study which finds that fish also enjoy the act of playing.

According to a report from Zee News, this study comes from studying members of the cichlid fish species, which includes such fish as tilapia. Researchers conducted their study by filming three male fish over the course of two years. During that time they noticed that the fish would repeatedly strike a bottom weighted thermometer. While this could of just been routine behavior, it constitutes as play due to the fact that this persisted despite the presence of food, environment or other fish in the tank.

According to Gordon Burghardt, one of the scientists who oversaw the study, the “quick righting response” was the main stimulus that made the fish hit the thermometer. In this case, that would be considered a form of playing. This type of reactive behavior has been seen in other animal species, such as octopi pulling balls underwater and watching them pop back up, and is also a factor in children’s toys. This data helps shed light on categorizing what exactly play is and how to apply it to the whole of the animal kingdom.

This compiled data is also very significant in animals beyond just fish. This new knowledge suggests that there are many other species that may also experience forms of play as well. These include animals that were previously thought not to play such as reptiles and wasps. As such, play may be more than random behavior, but an intrinsic part of evolutionary behavior and history.