From Getty Images as shown in the article.
We think of laughter as a uniquely human trait. Laughter for us is inborn — even deaf babies laugh. Plus there is a cultural component, as people in some cultures laugh more than others, but it’s a universal part of our behavior.
Now scientists are saying it’s an important part of animals’ behavior too. New research at the University of California, Los Angeles, finds there are probably at least 65 different creatures that make laughter vocalizations. As you might guess, they’re common in primates, but they have also been observed in species like birds. It’s not clear whether laughter has developed multiple times through evolution or we simply haven’t noticed how common it is.
If this surprises you, it’s because animal laughter sounds different. For example, the Rocky Mountain elk makes a kind of squealing sound. On the other hand, the animal with perhaps the biggest reputation for laughing, a hyena, really isn’t.
Animals usually use these vocalizations as a play signal, indicating they mean no harm even though the action may look aggressive. This keeps things under control so no one gets hurt. Dogs may even bow before playing, and they have a distinctive kind of panting.
Of course, there’s still a lot we don’t know. These findings were reached through a data search of animals making noises during play sessions in articles as far back as 1931. So more research is needed. Maybe this could explain where human laughter came from? In any event, it’s becoming recognized as one more trait that we have in common with animals.
Taken from “From Apes to Birds, There are 65 Animal Species that “Laugh”” by Doug Johnson (https://arstechnica.com/science/2021/05/from-apes-to-birds-there-are-65-animal-species-that-laugh/?).