It's not just us! A recent study has found that the joy of laughter is actually quite common in the animal kingdom too.
Scientists at UCLA explored the occurrence of laughter across different animal species by analysing existing scientific literature on animal play behavior. The team looked for mentions of vocal play signals as an indication of the presence of laughter in animals.
At the end of their study, published in Bioacoustics (the international journal of animal sound and its recording), the researchers claimed to have found laughter across at least 65 species of animals. These included primates, cows, dogs, foxes, seals, mongooses, as well as a few bird species such as parakeets and Australian magpies.
“This work lays out nicely how a phenomenon once thought to be particularly human turns out to be closely tied to behavior shared with species separated from humans by tens of millions of years,” said study author Greg Bryant, professor of communication at UCLA.
As part of the study, the researchers paid attention to details such as whether the animal’s vocal signals were recorded as noisy or tonal, loud or quiet, high-pitched or low-pitched, short or long - all in a bid to identify familiar characteristics of play sounds.
“When we laugh, we are often providing information to others that we are having fun and also inviting others to join,” said study author Sasha Winkler. “Some scholars have suggested that this kind of vocal behavior is shared across many animals who play, and as such, laughter is our human version of an evolutionarily old vocal play signal.”
It's expected that the study findings will help scientists better understand the function of human laughter and shed light on its role in the evolution of our social behavior.