Why do humans laugh

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You need to enable JavaScript to run this app. Why do humans laugh? Big ideas reflecting our evolution and what makes us intrinsically human. And some of the research has come out of the lab to investigate humor in its natural habitat: everyday life. For more than 2, years pundits have assumed that all forms of humor share a common ingredient. The search for this essence occupied first philosophers and then psychologists, who formalized the philosophical ideas and translated them into concepts that could be tested.

Perhaps the oldest theory of humor, which dates back to Plato and other ancient Greek philosophers, posits that people find humor in, and laugh at, earlier versions of themselves and the misfortunes of others because of feeling superior. The 18th century gave rise to the theory of release. When the punch line comes, the energy being expended to suppress inappropriate emotions, such as desire or hostility, is no longer needed and is released as laughter. A third long-standing explanation of humor is the theory of incongruity.

People laugh at the juxtaposition of incompatible concepts and at defiance of their expectations—that is, at the incongruity between expectations and reality.

According to a variant of the theory known as resolution of incongruity, laughter results when a person discovers an unexpected solution to an apparent incongruity, such as when an individual grasps a double meaning in a statement and thus sees the statement in a completely new light. These and other explanations all capture something, and yet they are insufficient. They do not provide a complete theoretical framework with a hypothesis that can be measured using well-defined parameters.

They also do not explain all types of humor. None, for example, seems to fully clarify the appeal of slapstick. In in the journal Psychological Science, A. Humor results, they propose, when a person simultaneously recognizes both that an ethical, social or physical norm has been violated and that this violation is not very offensive, reprehensible or upsetting. Hence, someone who judges a violation as no big deal will be amused, whereas someone who finds it scandalous, disgusting or simply uninteresting will not.

Experimental findings from studies conducted by McGraw and Warren corroborate the hypothesis. Consider, for example, the story of a church that recruits the faithful by entering into a raffle for an SUV anyone who joins in the next six months. Study participants all judged the situation to be incongruous, but only nonbelievers readily laughed at it. Levity can also partly be a product of distance from a situation—for example, in time.

It has been said that humor is tragedy plus time, and McGraw, Warren and their colleagues lent support to that notion in , once again in Psychological Science. The recollection of serious misfortunes a car accident, for example, that had no lasting effects to keep its memory fresh can seem more amusing the more time passes.

Geographical or emotional remoteness lends a bit of distance as well, as does viewing a situation as imaginary. In another test, volunteers were amused by macabre photos such as a man with a finger stuck up his nose and out his eye if the images were presented as effects created with Photoshop, but participants were less amused if told the images were authentic.

Conversely, people laughed more at banal anomalies a man with a frozen beard if they believed them to be true. McGraw argues that there seems to be an optimal comic point where the balance is just right between how bad a thing is and how distant it is.

Several other theories, all of which contain elements of older concepts, try to explain humor from an evolutionary vantage. Gil Greengross, an anthropologist then at the University of New Mexico, noted that humor and laughter occur in every society, as well as in apes and even rats. This universality suggests an evolutionary role, although humor and laughter could conceivably be a byproduct of some other process important to survival.

Wilson is a major proponent of group selection, an evolutionary theory based on the idea that in social species like ours, natural selection favors characteristics that foster the survival of the group, not just of individuals.

Wilson and Gervais applied the concept of group selection to two different types of human laughter. Spontaneous, emotional, impulsive and involuntary laughter is a genuine expression of amusement and joy and is a reaction to playing and joking around; it shows up in the smiles of a child or during roughhousing or tickling. This display of amusement is called Duchenne laughter, after scholar Guillaume-Benjamin-Amand Duchenne de Boulogne, who first described it in the midth century.

Conversely, non-Duchenne laughter is a studied and not very emotional imitation of spontaneous laughter. People employ it as a voluntary social strategy—for example, when their smiles and laughter punctuate ordinary conversations, even when those chats are not particularly funny. In a study that spanned 24 different societies and included participants, scientists played short sound bites of pairs of people laughing together.

In some cases, the pair were close friends, in others, the pair were strangers. Participants in the study were asked to listen to the simultaneous laughter and determine the level of friendship shared by the laughers.

Using only the sound of the laughter as cues, they could reliably tell the difference between people who had just met and those who were long-time friends. Another theory, which takes the person-to-person connection provided by laughter a step further, is that laughter may be a replacement for the act of grooming each other. Grooming another is a behavior seen in primates. To groom someone else is a generous, one-sided act. Because it requires trust and investment of time, it bonds the groomer and groomee as friends.

So, this is no longer our preferred method of exhibiting an offer of friendship. But laughter, like the commitment offered through grooming, is also hard to fake, at least not without being obvious. And, unlike grooming, it can be done in a larger group and gives a more immediate impression.

When we genuinely laugh, we signal that we are comfortable and feel like we belong. According to the Mayo Clinic, there are also a multitude of physical health benefits to laughter. Laughter can increase your oxygen intake , which can in turn stimulate your heart, lungs, and muscles. Laughing further releases endorphins, the feel-good chemicals our bodies produce to make us feel happy and even relieve pain or stress. The act of increasing and then decreasing our heart rate and blood pressure through laughter is also ultimately calming and tension-relieving.

Laughter can even boost our immune system response through the release of stress-and illness-reducing neuropeptides.

So laughter signals cooperation, a key aspect of human survival, and promotes a healthier body to boot.