A recent study has found that humans and great apes share striking similarities in the way they produce giggles, suggesting that this form of laughter has been preserved since their evolutionary split. Researchers examined tickling-induced laughter in 13 captive great apes—gorillas, orangutans, chimpanzees, and bonobos—and compared those sounds to new recordings of four young children being tickled and playing at home.

The analysis revealed that the rhythmic patterns of laughter in both humans and great apes exhibit a comparable timing, indicating a shared communicative function that dates back approximately 15 million years to a common ancestor. “In a way, we are very similar to other great apes because we’ve been laughing in a similar way for 15 million years,” said Chiara De Gregorio, a primatologist at the University of Warwick and lead author of the study.

Laughter serves as a nonverbal expression of playfulness and happiness across species. While many animals emit vocalizations that resemble laughter, the structure and acoustic patterns often differ from those of humans and their closest relatives. For instance, although rats respond to tickling with ultrasonic squeaks, these sounds do not closely resemble human laughter patterns.

Previous research on the evolution of laughter has largely focused on facial expressions associated with laughter, but less attention has been given to the auditory aspects. This study highlights that the sound patterns of great ape giggles provide new insights into the evolutionary roots of human laughter. Nonetheless, human laughter has evolved to become more rapid and complex, varying greatly depending on social context—from a restrained chuckle during formal interactions to more robust laughter shared among close friends.

The findings underscore the deep evolutionary connections between humans and great apes and open avenues for further research into the social and communicative roles of laughter across species.