Anyone who has owned a pet understands that animals can have complex emotional lives. They feel sorrow, guilt, joy, and anger – and now scientists believe many animals even have a sense of humor. While researchers haven’t really studied giggling animals in the past, new studies hope to answer the question of whether or not animals can laugh.
There are countless anecdotal stories of animals acting mischievously or appearing to double over with laughter, but is their data to back up these observations? There are many types of vocal responses that can be interpreted as animals laughing, though these phenomena are only observed in mammals and birds to date. The truth is, scientists don’t know much about the evolution of humor, but the little that is known suggests animals that laugh might be more common than anyone previously believed.
Marine researchers in Sweden have observed some of the best evidence to date of dolphin laughter, and they believe it has an important role in socialization. When engaging in play-fighting, dolphins emit a specific noise that seems to indicate their intentions as non-threatening. This only occurs during playful interactions and never during actual fights, leading researchers to believe that this sort of dolphin “chuckle” is meant to signal the roughhousing is all in good fun.
Keas are a playful species, even when they are alone, and scientists discovered that one of their calls has a unique emotional effect on the birds. They played a recording of a kea “laughing,” and saw that it caused other keas to respond and begin playing on their own or with nearby birds.
The fact that the warbling call evoked responses in solitary birds led researchers to rule out the possibility of it being an invitation to play. Their conclusion was that the sound put the birds in a good mood, impacting their emotions much like human laughter does.
Socialization and play are very important for these animals, especially bonobos, and laughter may help them discover their personal boundaries.
Some anecdotes suggest Koko is able to crack jokes, often to the frustration of her handlers. An experiment designed to test her ability to mimic movements failed when Koko began intentionally screwing up the moves. When the researcher would touch his nose, Koko would find amusement in pointing to completely different body parts. Her handler allegedly got frustrated and signed “bad gorilla”; Koko’s responded by signing “funny gorilla.”
Scientists ran a study in which certain sounds were played for a dog, including barks, growls, and panting, and the dog’s reactions were recorded. They discovered that dogs have their own version of laughter, a breathy exhale signifying the beginning of playtime. When the sound is played for a dog, it immediately attempts to instigate play with the source of the sound, whether the source is another dog or a human with a tape recorder. Just playing the sound can cause an immediate decrease in stress levels, a tactic that could potentially be used in high-stress environments like animal shelters.