MISSOULA — Laughter is common, but it’s a somewhat mysterious part of our evolution. How did laughter evolve? And are humans the only ones who do it?
It’s clear to scientists that we laugh as a part of play, signaling to others we are friendly and not aggressive — and we aren't the only species that laugh. Researchers from UCLA found vocal play behavior in at least 65 species of animals. The list ranges from monkeys to dolphins to foxes and seals to even your dog.
Since what constitutes “play” in much of the animal world is rough -- and it can also resemble fighting -- play sounds can help emphasize non-aggression during these physical moments.
This research lays out 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.
The study of play vocalizations is part of a much larger operation of understanding the nature of animal communication systems, and the related puzzle of human communication.
Laughter might be one of the best examples of communicative behavior that allows for comparative research while remaining ingrained within our uniquely human language and culture.
Future research will undoubtedly lead to new discoveries regarding the many connections between human and animal vocalizations. There is still much to learn, so keep laughing.