Why Is Yawning Contagious?

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iStock

What is yawning? And why do we do so much of it? Neuroscientist and yawn expert Robert Provine says it's "ancient and autonomic." It stems from early evolution and is common to many creatures—even fish do it. It's autonomic in the sense that it roots in the brainstem, way down in the basement level of the brain, where certain responses are so built-in they don't even qualify as reflexes.

Yawning has many triggers, including boredom, sleepiness, and temperature. A 2014 study suggested that there's a "thermal window" (at around 68°F) for human yawning; as ambient temperature approaches body temperature or goes down near freezing, we yawn less. According to the paper, we may yawn to regulate the temperature of our brains. This isn't the same as saying we yawn to take in extra oxygen, as evidence to date says we don't. It means that yawning might act to draw brain-soothing ambient air in through the nose and mouth.

COPYCAT YAWNING?

Over the years, scientists have observed "contagious yawning" in chimpanzees, humans, baboons, bonobos, wolves, and, to a certain extent, dogs. Yawning feels good, so why not join in when someone else yawns? Well, you're not really "joining in," because you aren't copying the yawn on any conscious level. It happens because you just can't help it. If you become self-conscious about a yawn, it stops.

While many past studies have documented the phenomenon, a more recent study, published in the journal Adaptive Human Behavior and Physiology, contends that yawns may not be contagious after all—or at least that we have not yet proven it. Experimental psychologist Rohan Kapitány of the University of Oxford conducted a review of the scientific literature on contagious yawns and found very little conclusive evidence to back up our long-held assumption that yawns are contagious.

"The belief that yawns are contagious seems self-evident," Kapitány told PsyPost, "but there are some very basic reasons for why we might be mistaken in this. If we fail to dissect that which we think we know, we might end up with conclusions that do not reflect reality. In this instance, the literature hasn't questioned the basic features of contagious yawning, and ended up with a wide range of unstandardized methodologies and conclusions."

Still, because Kapitány's study was small and extremely limited, he and his fellow authors urge other scientists to challenge their findings with experiments of their own.

"I may be wrong!" Kapitány said. "Maybe yawns are contagious!" Kapitány says he'd like to see "more robust" attempts to falsify the claim that yawns are contagious rather than "simply demonstrating it over and over [in] slightly different contexts with richer and richer explanations."

WHO DOESN'T CATCH YAWNS?

Some people with autism or schizophrenia don't exhibit a yawn-contagion response. The same is true of children under the age of four years. This has led to a variety of theories about yawning's relationship to empathy and the brain's mirror-neuron system (MNS). The idea here is that MNS deficits might lead to missing hidden empathetic cues that trigger contagious yawning. The MNS seems to be involved in the process to some extent. fMRI scans on a range of people have shown that other parts of the brain also "light up" in response to images of yawning, perhaps more so than the areas normally associated with empathy.

YAWN AND RUN

Parts of the amygdala—a brain area associated with fear and heightened attention—light up in response to images of yawning. We sometimes yawn when we're nervous, such as before a sporting performance.

So, perhaps we yawn at those times to prepare our brains for "fight or flight." Maybe contagious yawning is a smart evolutionary shortcut for readying the brains of an entire group of hominins for swift action in response to a threat. (If that's the case, then some older members would have been left behind, because older people are a little less susceptible to yawn contagion.) We are social mammals; this kind of evolutionary refinement of an existing trait (general purpose yawning becoming contagious yawning) might have helped groups to survive.

Or maybe it's a lot less deep than that. Laughing also feels good, and it too can be contagious. Like laughter, contagious yawning might help groups to bond—by signaling unselfconscious, relaxed sleepiness. Perhaps it has more to do with feeling safe than with feeling threatened.

STRAGGLERS AND FAKES

Contagious yawning is still a bit of a scientific mystery. We love to speculate about it and try to home in on the reason for it. But why should an evolutionary trait have one specific reason behind it? Often, traits survive because they cover a number of bases. Other times, they're simply evolutionary stragglers whose original purpose has faded out, but because they don't work against a creature's survival, there's no pressure to get rid of them.

One modern adaptation of yawning is not so contagious—fake yawning. You might do this as a less-than-subtle means of signaling that a conversation has dragged on too long. Why not engage in a scientific experiment next time you're in a meeting with your boss? Lean back in your chair and yawn, then note down whether he or she yawns right back at you. Maybe there's a scientific discovery in there … but probably no pay raise.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

Looking to Downsize? You Can Buy a 5-Room DIY Cabin on Amazon for Less Than $33,000

Five rooms of one's own.
Five rooms of one's own.
Allwood/Amazon

If you’ve already mastered DIY houses for birds and dogs, maybe it’s time you built one for yourself.

As Simplemost reports, there are a number of house kits that you can order on Amazon, and the Allwood Avalon Cabin Kit is one of the quaintest—and, at $32,990, most affordable—options. The 540-square-foot structure has enough space for a kitchen, a bathroom, a bedroom, and a sitting room—and there’s an additional 218-square-foot loft with the potential to be the coziest reading nook of all time.

You can opt for three larger rooms if you're willing to skip the kitchen and bathroom.Allwood/Amazon

The construction process might not be a great idea for someone who’s never picked up a hammer, but you don’t need an architectural degree to tackle it. Step-by-step instructions and all materials are included, so it’s a little like a high-level IKEA project. According to the Amazon listing, it takes two adults about a week to complete. Since the Nordic wood walls are reinforced with steel rods, the house can withstand winds up to 120 mph, and you can pay an extra $1000 to upgrade from double-glass windows and doors to triple-glass for added fortification.

Sadly, the cool ceiling lamp is not included.Allwood/Amazon

Though everything you need for the shell of the house comes in the kit, you will need to purchase whatever goes inside it: toilet, shower, sink, stove, insulation, and all other furnishings. You can also customize the blueprint to fit your own plans for the space; maybe, for example, you’re going to use the house as a small event venue, and you’d rather have two or three large, airy rooms and no kitchen or bedroom.

Intrigued? Find out more here.

[h/t Simplemost]

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Who Were the Actual Brooks Brothers?

Phillip Pessar, Flickr // CC BY 2.0
Phillip Pessar, Flickr // CC BY 2.0

Brooks Brothers has been a mainstay of American formal wear for more than 200 years. The company’s suits have been worn by 40 U.S. presidents. They have supplied uniforms to the American armed forces and suits to regular people for their most important life events: going to the prom, attending their first job interview, getting married.

But in July 2020, the firm filed for bankruptcy, likely a victim of the working-from-home trend and the move towards more casual clothing. The Brooks Brothers’s name has been woven into the fabric of American fashion, yet a certain mystery surrounds the people behind the business. Who were the original Brooks Brothers, anyway?

The firm that would go on to be known as Brooks Brothers was established on April 7, 1818, by 45-year-old Henry Sands Brooks and his younger brother, David, as H & D. H. Brooks and Co. Before setting up the store, Henry Sands Brooks had been a provisioner for traders and seafarers, and likely did brisk business in New York City’s seaport. Their shop was situated on the corner of Catherine and Cherry streets in Lower Manhattan, a major shopping district that supported a number of clothing stores. It was said Brooks was something of a dandy with an eye for fashion.

Brooks Brothers ran a full-page ad celebrating its centenary in 1918.New York Evening Post // Public Domain

Henry Sands Brooks died in 1833, and the store passed to his eldest son, Henry Jr. When he died in 1850, Brooks Sr.’s four younger sons Daniel, John, Elisha, and Edward inherited the firm and renamed it Brooks Brothers. At this point, the store began to stand out from the crowd. The brothers adopted their familiar logo of a sheep suspended by a ribbon representing the Golden Fleece. This ancient symbol hearkened back to the Greek legend of Jason and the Argonauts, and was used by tailors and wool merchants across Europe as a sign of quality. By embracing this symbol, the brothers were announcing the caliber of their goods and aligning themselves with the prestige of European fashion.

While building a brand on traditional quality, the brothers also saw an opportunity to modernize. Brooks Brothers began specializing in ready-to-wear suits—an innovation that made “gentlemen’s clothing” accessible and affordable to ordinary Americans. An advertisement in New York’s Evening Post in June 1850 stated that Brooks Brothers ‘have on hand a large stock of ready-made clothing, suited to the tastes and wants of purchasers.’ Brooks Brothers also capitalized on the California Gold Rush by selling their ready-made suits to gold-seekers who didn’t have time to wait for a tailor to construct bespoke suits.

Business boomed in the years leading up to the Civil War, a time when the company benefited from slavery. Much of the cotton used by Brooks Brothers was picked by enslaved laborers in the South. The company also manufactured the types of uniforms worn by enslaved people forced to work as house servants.

Perhaps as a result of their experience making such clothing, Brooks Brothers was given a large contract by the Union government at the start of the Civil War to provide tens of thousands of uniforms for enlisted soldiers. A scandal blew up when the garments were delivered: it was obvious that the uniforms were of low quality, missing buttons or buttonholes, and made from cheap scraps of cloth glued instead of sewn together. When the outfits were exposed to wind and rain, they fell apart. In the rush to manufacture them for the war effort, Brooks Brothers had, in fact, substituted cheap and flimsy material instead of the usual grade of cloth—they were allowed to, according to the provisions written into their contract.

The New York state legislature launched an investigation, accusing the company of profiteering. When asked how much money the company had made by downgrading the cloth, Elisha Brooks prevaricated. “I think that I cannot ascertain the difference without spending more time than I can now devote to that purpose,” Brooks told lawmakers. Ultimately, Brooks Brothers agreed to replace 2350 of the substandard uniforms at a cost of $45,000.

An illustration of looters throwing trousers and other garments out of the Brooks Brothers store during New York City's draft riots appeared on the front page of Frank Leslie's Illustrated Newspaper on August 1, 1863.Frank Leslie's Illustrated Newspaper, 19th Century American Newspapers, Gale Primary Sources // Public Domain

The company’s association with outfitting the Union Army got them into trouble again in July 1863. The casualties among members of New York regiments were increasing as the war showed no signs of resolution. In New York City, working class people protested against the draft, and the protests quickly turned into a riot of racist violence and looting. Brooks Brothers’s Cherry Street store was one of the establishments it targeted. Harper’s Weekly reported that “a large number of marauders paid a visit to the extensive clothing-store of Messrs. Brooks Brothers … there they helped themselves to such articles as they wanted, after which they might be seen dispersing in all directions, laden with their ill-gotten booty.”

Brooks Brothers’s reputation didn’t suffer for long, however. At his second presidential inauguration in March 1865, Abraham Lincoln wore a greatcoat made by the company. It featured an eagle embroidered into its lining with the motto “One Country, One Destiny.” Lincoln was wearing the same coat when, just two weeks later, he was assassinated at Ford’s Theatre in Washington, D.C. After his death, Mary Todd Lincoln gave the coat to Alphonse Donn, a doorman at the White House, who kept it for the rest of his life. Donn’s family eventually sold the coat to the United States Capitol Historical Society, and it is now in the Ford’s Theatre museum's collection.

Brooks Brothers continued to grow and expand. The company introduced enduring fashions such as the button-down polo shirt in 1896, the sack suit in 1901, and their own version of a British regimental tie, the striped rep tie, in 1902.

For more than 200 years, the company has outfitted presidents, Wall Street traders, and businesspeople, becoming an iconic American brand with worldwide appeal. But today, their future may be less certain.