The question of whether animals possess a sense of humor is complex, largely because “humor” is deeply tied to human language and culture. We define humor through complex cognitive mechanisms like understanding a joke or appreciating satire, abilities generally absent in other species. Scientists investigate whether non-human animals experience or express something akin to amusement or joy by studying related behaviors like intentional teasing, play, and the violation of social expectations. The presence of these behaviors in many species suggests that the evolutionary roots of our own capacity for humor may be far older than previously assumed.
Defining Amusement in Animal Behavior
To study amusement in the animal kingdom, researchers identify non-serious, humor-like behavior. The most reliable marker is play, which is non-utilitarian; it does not serve an immediate purpose like hunting, mating, or fighting. Play is characterized by exaggerated, repetitive actions that seem out of context, such as a predatory pounce that stops short of actual contact.
Many social animals employ specific signals, known as meta-communication, to indicate that their actions are playful and not genuine aggression. Canids use the “play bow,” where a dog dips its front end down while keeping its rear elevated, signaling that the ensuing chase is not real. Primates use a “play face,” an open-mouth, relaxed expression often accompanied by a panting vocalization similar to human laughter.
These signals allow animals to engage in behaviors that would normally be threatening without causing conflict. Rats, for example, emit high-frequency, 50-kilohertz ultrasonic chirps when engaged in rough-and-tumble play or when tickled. This vocalization acts as “rat laughter,” indicating pleasure and a desire to continue the interaction.
Intentional Teasing and Practical Jokes
Beyond general play, some animals exhibit intentional, directed teasing. Great apes are frequently observed engaging in playful provocation, involving actions like poking, hitting, or obstructing another individual’s movement. These acts are deliberate, persistent, and aimed at eliciting a specific, non-aggressive reaction from the target.
One notable example involves a young chimpanzee who would regularly wrap herself in a blanket and chase her peers, acting like a “ghost.” The other chimpanzees would run until the “ghost” suddenly removed the blanket, at which point the group would erupt in what observers described as laughter. This behavior is considered a rudimentary practical joke because it relies on the element of surprise and the violation of a temporary expectation.
Parrots, known for their high intelligence, also display provocative behavior. Anecdotes describe parrots intentionally calling a family dog’s name to encourage it to approach, only to laugh when the dog arrived for no reason. Another macaw was observed waiting until its enclosure was swept clean before deliberately scooping seeds from its bowl and flinging them onto the floor. The bird would then hang upside down and “laugh” at the resulting mess, indicating an intentional action designed to cause a predictable disruption.
Cognitive Abilities Required for Humor
The ability to engage in intentional teasing requires advanced cognitive abilities, suggesting a potential sense of humor exists in species with complex brains. A primary prerequisite is Theory of Mind (ToM), the capacity to understand that others possess mental states, such as beliefs, desires, and intentions, that may differ from one’s own. Intentional teasing relies on ToM, as the teaser must know what the target expects and then deliberately violate that expectation.
A second requirement for humor is the ability to detect incongruity—the mismatch between an expectation and reality. The chimp “ghost” game illustrates this: the surprise relies on the expectation of being chased by a spooky figure being suddenly broken by the reveal of a playmate. The subsequent laughter or vocalization signals that the tension caused by the incongruity has been released and is safe.
The presence of self-awareness, often tested by mirror recognition, further supports complex social cognition. Species that pass this test, including great apes, dolphins, and elephants, are frequently observed engaging in sophisticated play and teasing. For instance, Koko the gorilla, who learned American Sign Language, reportedly used signs for humorous effect, such as signing “chase” after tying her trainer’s shoelaces together. This requires anticipating the trainer’s reaction and understanding the relationship between actions and communication to create a joke.
The Role of Playful Behavior in Development
The playful and humor-like behaviors observed in young animals are not frivolous; they serve a significant purpose in physical, social, and emotional development. Engaging in mock aggression and chasing helps young animals refine their motor skills, improving coordination and strength needed for adult survival. This physical practice is important for species that rely on agility or complex hunting techniques.
Social play acts as a low-stakes training ground for learning the complex rules of group dynamics. Through play, young animals learn to communicate intent effectively, practice conflict resolution, and establish social boundaries without serious fighting. Signaling non-aggression, such as through a play-bow or play-face, is a fundamental lesson in social competence. Play also provides mental stimulation, encouraging problem-solving skills and adaptability. Ultimately, this capacity for non-serious, joy-inducing interaction contributes to emotional well-being by providing stress release and strengthening social bonds.