Human curiosity has long been captivated by the question of whether animals laugh. While animal “laughter” may not mirror human chuckles, science reveals many species produce specific vocalizations linked to play and positive social interactions. These sounds offer insights into their emotional states and social behaviors, indicating a form of playful communication exists across diverse species.
What Does “Laughter” Mean for Animals?
Scientists define “laughter-like” animal vocalizations as sounds linked to play, tickling, or positive social interactions. These sounds are distinct from distress or aggression calls and involve specific patterns, such as panting, chirping, or chattering during playful activities. Comparing them to human laughter is challenging, as human laughter has evolved unique acoustic features and is often louder. Researchers instead look for sounds that signal a playful, non-threatening interaction. Vocalizations that signal play are widespread across various species, including mammals and birds. This indicates a broader interpretation of “laughter” is necessary, focusing on context and communicative intent rather than just acoustic similarity to human sounds.
The Animal Kingdom’s Playful Voices
Many animals exhibit distinct “laughter-like” vocalizations during play. Primates like chimpanzees, gorillas, bonobos, and orangutans produce pant-like sounds when tickled or engaged in wrestling and play-chasing. Chimpanzee laughter, for example, sounds like breathing and panting due to alternating inhalations and exhalations. Bonobo laughter, while higher in frequency, shares sonographic patterns and facial expressions with human baby laughter when tickled.
Beyond primates, rats also exhibit playful vocalizations, emitting 50-kHz ultrasonic chirps when tickled or during rough-and-tumble play. These chirps are too high for humans to hear without special equipment but indicate positive emotional states in rats. Dogs display a form of “laughter” through a specific panting that differs from regular panting used for temperature regulation. Recordings of this “play panting” can encourage play and reduce stress in other dogs. Some bird species, like the New Zealand kea parrot and Australian magpies, also produce distinct play sounds. Kea parrots make a “play call” that can induce a playful mood and initiate play in other keas.
Why Do Animals “Laugh”?
Animal “laughter-like” vocalizations serve various social and evolutionary purposes. These sounds primarily signal playfulness, ensuring rough interactions do not escalate into aggression. By vocalizing during play, animals communicate that the interaction is friendly and not a threat. This signaling helps maintain positive social bonds within groups.
These vocalizations also communicate positive emotional states during social interactions. For instance, the ultrasonic chirps of rats indicate a positive emotional state, and rats that vocalize more during tickling tend to be more optimistic. The presence of these play vocalizations across many species suggests shared evolutionary roots of social communication. Such sounds might be precursors to human laughter, highlighting how an ancient form of vocal signaling for play evolved. Studying these animal sounds provides a deeper understanding of animal emotions and the complexity of their social lives.