Scientists have uncovered considerable documentation suggesting that animals other than humans laugh. The researchers examined the existing scientific literature on animal play behavior, looking for mentions of vocal play signals — or what might be thought of as laughter. They found such vocal play behavior documented in at least 65 species. That list includes a variety of primates, domestic cows and dogs, foxes, sea lions, and mongooses, as well as three bird species, including parakeets and Australian magpies.
The researchers looked for information on whether the animal vocalizations were recorded as noisy or tonal, loud or quiet, high-pitched or low-pitched, short or long, a single call or a rhythmic pattern — seeking known features of play sounds. The researchers discovered there is considerable scientific documentation of play-based body language among animals, such as what is known as “play face” in primates or “play bows” in canines…
Complex social play is well-documented across many animals. During play, animals often use signals that facilitate beneficial interactions and reduce potential costs, such as escalation to aggression. Although greater focus has been given to visual play signals, here we demonstrate that vocalizations constitute a widespread mode of play signalling across species. Our review indicates that vocal play signals are usually inconspicuous, although loud vocalizations, which suggest a broadcast function, are present in humans and some other species. Spontaneous laughter in humans shares acoustic and functional characteristics with play vocalizations across many species, but most notably with other great apes. Play vocalizations in primates and other mammals often include sounds of panting, supporting the theory that human laughter evolved from an auditory cue of labored breathing during play.
Journal Reference: Winkler, S. & Bryant, G. Play vocalizations and human laughter: a comparative review, Bioacoustics Journal, April, 2021. https://doi.org/10.1080/09524622.2021.1905065