Last week, we explored our fondness for sugar and the evolutionary reasons behind seemingly counter-survival traits. This week, let’s delve into a trait that, while not contradictory to survival, might appear somewhat superfluous: laughter. Why Do We Laugh?
Laughter is a universal human expression, transcending cultural boundaries. While humor may be subjective and vary across cultures – as humorously highlighted by a job interview anecdote in the Netherlands where jokes fell flat – the act of laughing is inherently human. Intriguingly, humans are not alone in this behavior; apes also exhibit laughter. This has been scientifically observed and confirmed by researchers who study animal behavior, sometimes through the unusual method of tickling animals – a testament to the dedication of science!
Humans begin to laugh remarkably early in life, as young as 3 months old, even before developing speech. This phenomenon is consistent across infants, including those born deaf or blind. The universally appealing game of peekaboo is a prime example of a laughter trigger in babies worldwide. The study of infant laughter is a legitimate field of scientific inquiry, further emphasizing the significance of this seemingly simple act.
The pervasiveness of laughter across ages, cultures, and even species suggests it serves a fundamental purpose. But what exactly is the reason behind our laughter? Let’s explore some scientific explanations.
The Social Dynamics of Laughter
One of the primary functions of laughter is social. It acts as a signal for connection and social bonding. Research indicates that in conversations, speakers are significantly more prone to laughter (approximately 46 percent more likely) than listeners. This suggests laughter is used to engage and connect with the audience.
Furthermore, the social context dramatically influences laughter. We are about 30 times more likely to laugh when in a group compared to being alone. Studies on young children (aged 2.5 to 4) watching cartoons revealed they were eight times more likely to laugh when watching with another child, even if their individual rating of the cartoon’s funniness remained the same regardless of company. This highlights the powerful social contagion of laughter.
From an evolutionary standpoint, this signaling of connection was likely crucial for survival. When encountering a stranger, assessing their intentions and alliances was vital. Laughter could have played a role in quickly establishing social bonds and trust.
A study spanning 24 diverse societies with nearly a thousand participants investigated this further. Participants listened to audio clips of pairs laughing together, some pairs being close friends, others strangers. Remarkably, listeners could reliably distinguish between the laughter of friends and strangers solely based on auditory cues. This implies a strong link between genuine laughter and true friendship, and suggests that forced laughter is often transparent.
Laughter as a Social Glue: Replacing Grooming
Expanding on the social connection aspect, another theory posits that laughter might have evolved as a human substitute for grooming, a behavior observed in primates. Grooming, a generous and time-investing act, fosters bonding and friendship between primates.
As human societies grew larger, physical grooming became impractical for maintaining widespread social bonds. Laughter emerged as a more efficient and group-friendly alternative. Like grooming, genuine laughter is difficult to fake convincingly. However, unlike grooming, laughter can involve multiple individuals simultaneously and create an immediate sense of camaraderie. Authentic laughter signals comfort, belonging, and shared positive emotion within a group.
The Health Perks of Laughter
Beyond social benefits, laughter offers significant physical health advantages, as outlined by the Mayo Clinic. Laughter increases oxygen intake, stimulating the heart, lungs, and muscles. It triggers the release of endorphins, the body’s natural mood elevators and pain relievers. The physiological process of laughter, involving increased and then decreased heart rate and blood pressure, ultimately leads to a calming and tension-relieving effect. Moreover, laughter can bolster the immune system by releasing neuropeptides that combat stress and illness.
In conclusion, laughter serves as a vital signal of cooperation, a cornerstone of human survival, and simultaneously enhances physical well-being. This provides a compelling rationale for prioritizing shared laughter with friends and loved ones – a delightful prescription for a healthier and more connected life.
