James Belarde //
“It seems to me that you can know a man by his laughter, and if from the first encounter you like the laughter of some completely unknown person, you may boldly say that he is a good man.” -Fyodor Dostoevsky, in Notes from A Dead House
“A woolly mammoth and a saber-tooth tiger walk into a cave.” That’s as far as I imagine most ancient jokes got before early nomadic humans were set upon by the constant struggles of their prehistoric lives: predator attacks, deadly natural disasters, and Barney Rubble always stealing your Cocoa Pebbles. Clearly this was not a time ripe with opportunities for laughter. But as discussed in part one of this series, there are clear indications from our closest primate relatives that primitive laughter did exist, eventually becoming the complex behavior we know today. How did this evolution take place?
In my last piece, I discussed one theory often mentioned in gelotology (“the study of laughter, and a fun word to sneak into conversation”), which concludes that laughter developed alongside language to encourage verbal play.1 Though intriguing, that hypothesis leaves several aspects of laughter’s origin unexplained. This includes the laugh-like play-pant behavior of our chimpanzee cousins. A more complete explanation of human laughter requires theorizing on the biological and societal changes that took place to enable the evolution of play-pants into genuine laughter before language developed.
Though I won’t focus on the biological aspect here, a fascinating “bipedal theory” of laughter suggests that an important step was when humans began to walk on two legs (my deepest apologies for the pun).2 This allowed our respiratory system to develop in such a way that we went from one sound for every breath in and out to a finer control of our respirations allowing for more sounds per breath. The former only results in simple panting, while the latter can create more complex laughter. This same feature of our two-legged breathing would eventually facilitate speech production too.
Even more difficult to identify, and what I’ll spend the rest of this article examining, are the changing social needs of early humans that resulted in laughter. Of the theories proposed to address this, a compelling one from Matthew Gervais and David Wilson in 2005 uses a synthetic approach.3 Conducting a thorough review of gelotology up to that year, they use their observations to hypothesize that laughter developed as an indicator to help primitive groups of humans realize they were in a non-threatening situation and could engage in playful or exploratory behaviors. The idea is that early nomadic humans were subject to constantly fluctuating levels of threat and safety. To become the more complex societies we are now, primitive humans needed to know when a context was safe enough to temporarily stay put. They could then participate in playful group bonding activities and expend cognitive energy on developing things like tools, early agricultural techniques, and quantum string theory (okay, maybe not that last one yet). According to Gervais and Wilson, laughter may have served to spread a perceived feeling of security among a group of nomadic humans.
One reason laughter is such a tempting answer to this problem is that it is a form of emotional contagion. Emotional contagion is the concept that human biology is primed to enable the spreading of emotional states from a single individual to a whole population of nearby humans. Just as an individual’s emotions motivate associated behaviors to accomplish a goal, when a group shares an emotional state, they can be motivated to act in concert for even loftier goals. Emotional contagion is thought to occur via use of specialized mirror neurons in the brain.3 These neurons are brain cells that are active not only when we do something ourselves, such as laughing or crying, but also when we observe others take the same action. Hence the term “mirror.” So once a context was recognized as safe by a handful of prehistoric humans, it’s possible that laughter-induced emotional contagion helped spread this knowledge throughout a larger population. This would ensure that they took the most advantage of an opportunity for exploration and play.
Gervais and Wilson go on to suggest that this early laughter developed into the spontaneous Duchenne laughter we know today (laughter accompanied by true feelings of joy). This makes sense given what we know about such sincere laughter in contemporary societies. Duchenne laughter almost always requires both a sense of security and community. For instance, the same activity (i.e. peekaboo) can make a baby either laugh or cry depending on how safe they feel. And the modern comedy world has known for decades that laughter engenders laughter. Hence the live studio audiences or recorded laugh tracks included in many popular sitcoms. These are added to encourage laughter from lone viewers. Clearly, the Navajo people intuited this important social aspect in choosing to celebrate a baby’s first laugh with the A’wee Chi’deedloh ceremony.
What about non-Duchenne laughter (which is forced or otherwise not accompanied by joyful sentiment) and the myriad of uses we now have for it? According to Gervais and Wilson’s theory, this was an instance of evolution recycling. As societies grew more complex, the sensation of laughter acquired more functions. This idea of evolution co-opting older developments for new uses isn’t unheard of. In fact, it’s been proposed for another primitive emotion: disgust. Originally evolving as a mechanism to keep early humans from ingesting toxic substances, researchers have studied how it was co-opted for use in reinforcing social norms and standards of morality. Something that initially kept us from gross things like poison now also keep us from gross things like picking our nose in public or eating vegetables (that second one might just be me). With this line of thinking, non-Duchenne laughter is the result of true joyful laughter evolving to fit more uses in an increasingly complex social environment. It became something to not only express a sense of security, but also humor appreciation, nervousness, derisive superiority, and malice (insert evil villain laugh here).

The field of gelotology is still young, and these are only theories. But the research behind them is strong and growing rapidly. With more advances in related fields like neuroscience, psychology, humor, and anthropology, we are poised to uncover much about the laugh. And what I find most fascinating about this question is that it encourages one to think about the ways in which our prehistoric human needs led to complex tools allowing for the development of the arts, including my favorite: standup comedy. Reflexes that were initially programmed to help us live are recycled to help us live more richly.
But despite the complexities of modern laughter and the resulting artistic opportunities, the proposed ancient connection between security and laughing remains strong. At a close friend’s recent wedding, the couple’s tendency to laugh with each other was continually cited as a strong indicator of their deep connection. Even more telling was seeing this on full display between the two and the comfort it afforded them throughout that wonderful, and no doubt busy, day. Two frequently cited factors important for many in choosing a longterm romantic partner are a sense of security and a sense of humor. If Gervais and Wilson’s evolutionary theory holds true, these may just be two sides of the same coin.
Featured Image: printed by Young’s, The Hatter, Public domain, via Wikimedia Commons
References
- Belarde, James. “Laughter Part 1: Which Came First, the Language or the Laugh.” Medical and Health Humanities, 15 Sept. 2019, https://medicalhealthhumanities.com/2019/09/15/laughter-part-1-which-came-first-the-language-or-the-laugh/. Accessed on 22 Sept. 2019
- Provine, Robert R. “Laughter as an approach to vocal evolution: the bipedal theory.” Psychon Bull Rev. 2017; 24:238-244.
- Gervais, M. and Wilson, D. S. “The evolution and functions of laughter and humor: a synthetic approach.” Quarterly Review of Biology. 2005; 80:395-430.