We all have our own unique laugh patterns. Our own signature laugh sounds. It should be no surprise that our primate cousins—chimpanzees, gorillas, bonobos, and orangutans—laugh too, and they all do it in their own distinctive ways, just like us. But according to a new study published in Communications Biology, there are way more similarities between our laughs than once thought.

Researchers analyzed decades-old recordings of tickled great apes alongside recordings of four young children laughing while playing and while being tickled. They found that humans and all great apes share the same basic rhythmic pattern of laughter, with evenly spaced vocal bursts known as an isochronous rhythm. That trait likely dates back to the last common ancestor humans shared with the great apes around 15 million years ago, making laughter one of the oldest traits handed down to us by our primate ancestors.

Scientists Say Human Laughter May Date Back 15 Million Years

Chimpanzees, bonobos, gorillas, and orangutans laugh with consistent rhythms. Humans, on the other hand, are always adjusting the speed and style of our laughter depending on the context. We belly laugh when a joke strikes the right chord, but then puff out a forced, exaggerated fake laugh to spare someone’s feelings. Apes just have one basic laugh. They either do it or they don’t, and they’re not going to spirit your feelings if they find the silly faces you make at them hacky and frankly a little insulting.

The researchers believe that our ability to control the rhythm and tempo of laughter is a part of the same vocal control system that allows us to speak. Laughter isn’t a part of language, necessarily, but both language and laughing require a fine control over the muscle that makes sound. The researchers suggest that we eventually evolved those abilities, and it seems that our closest primate relatives, like chimpanzees and bonobos, can do something similar, as they have more vocal flexibility than gorillas or orangutans. It’s only a matter of time before a chimp politely laughs at you so as not to destroy your fragile sense of human superiority.