Scientists: Maybe Yawning Isn’t Contagious After All

iStock
iStock

Everyone knows that yawning is contagious. What this new study presupposes is … maybe it isn’t? The report was published in the journal Adaptive Human Behavior and Physiology.

Anecdotal evidence—that is, our own lives—certainly suggests that the act of yawning spreads. Many studies have documented the phenomenon as well. And humans aren’t the only ones; we've seen rats, chimpanzees, dogs, and even parakeets pass yawns to each other.

But have we really proven it? Rohan Kapitány of the University of Oxford says no. The experimental psychologist conducted a review of the scientific literature on contagious yawns and found very little conclusive evidence to back up our assumption.

“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 unstandardised methodologies and conclusions.”

So Kapitány and his colleague Mark Nielsen designed an experiment to put those conclusions to the test. They recruited 79 college students—psychologists’ favorite guinea pigs—and broke them into small groups. Each group sat around a table together, wearing headphones that played Chopin’s Complete Nocturnes. Some of the participants were blindfolded, and some were not. The sessions were videotaped.

Afterward, the researchers calculated the number of times each person yawned, and when, and whether they did so after seeing somebody else do it.

On their surface, the initial results supported the contagious-yawn concept. The longer the participants sat in the room together, the more they yawned, especially if they could see other people.

But things got murkier once the researchers dug deeper into the data. Their findings suggested that one person’s yawn could not reliably make another person yawn within 3 minutes. Everybody yawned, but there didn’t seem to be a causal relationship between one person’s yawn and another’s.

This study was small and extremely limited, and the 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.”

NOTE: We used the word “yawn” 17 times in this article. We’re yawning now. We bet you are, too. More research is definitely needed.

[h/t PsyPost]

Amazon's Best Black Friday Deals: Tech, Video Games, Kitchen Appliances, Clothing, and More

Amazon
Amazon

This article contains affiliate links to products selected by our editors. Mental Floss may receive a commission for purchases made through these links.

Black Friday is finally here, and Amazon is offering great deals on kitchen appliances, tech, video games, and plenty more. We will keep updating this page as sales come in, but for now, here are the best Amazon Black Friday sales to check out.

Kitchen

Instant Pot/Amazon

- Instant Pot Duo Plus 9-in-115 Quart Electric Pressure Cooker; $90 (save $40)

- Keurig K-Cafe Special Edition; $190 (save $30)

- Ninja OS301 Foodi 10-in-1 Pressure Cooker and Air Fryer; $125 (save $75)

- Nespresso Vertuo Next Coffee and Espresso Machine by Breville; $120 (save $60)

- KitchenAid KSMSFTA Sifter with Scale Attachment; $95 (save $75)

- Keurig K-Mini Coffee Maker; $60 (save $20)

- Cuisinart Bread Maker; $80 (save $97)

- Anova Culinary Sous Vide Precision Cooker; $139 (save $60)

- Aicook Juicer Machine; $35 (save $15)

- JoyJolt Double Wall Insulated Espresso Mugs - Set of Two; $14 (save $10)

- Longzon Silicone Stretch Lids - Set of 14; $16 (save $11)

- HadinEEon Milk Frother; $37 (save $33)

Home Appliances

Roomba/Amazon

- iRobot Roomba 675 Robot Vacuum with Wi-Fi Connectivity; $179 (save $101)

- ASAKUKI 500ml Premium Essential Oil Diffuser; $22 (save $4)

- Facebook Portal Smart Video Calling 10 inch Touch Screen Display with Alexa; $129 (save $50)

- Bissell air320 Smart Air Purifier with HEPA and Carbon Filters; $280 (save $50)

- Oscillating Quiet Cooling Fan Tower; $59 (save $31)

- TaoTronics PTC 1500W Fast Quiet Heating Ceramic Tower; $55 (save $10)

- Vitamix 068051 FoodCycler 2 Liter Capacity; $300 (save $100)

- Ring Video Doorbell; $70 (save $30)

Video games

Sony

- Marvel's Spider-Man: Game of The Year Edition for PlayStation 4; $20 (save $20)

- The Legend of Zelda: Link's Awakening; $40 (save $20)

- Hyrule Warriors: Age of Calamity; $50 (save $10)

- Marvel's Avengers; $25 (save $33)

- The Last of Us Part II for PlayStation 4; $30 (save $30)

- LEGO Harry Potter: Collection; $15 (save $15)

- Ghost of Tsushima; $40 (save $20)

- BioShock: The Collection; $20 (save $30)

- The Sims 4; $24 (save $20)

- God of Warfor PlayStation 4; $10 (save $10)

- Days Gonefor PlayStation 4; $20 (save $6)

- Luigi's Mansion 3 for Nintendo Switch; $40 (save $20)

Computers and tablets

Microsoft/Amazon

- New Apple MacBook Pro 16 inches with 512 GB; $2149 (save $250)

- Microsoft Surface Laptop 3 with 13.5 inch Touch-Screen; $1200 (save $400)

- Lenovo ThinkPad T490 Laptop; $889 (save $111)

- Amazon Fire HD 10 Tablet (64GB); $120 (save $70)

- Amazon Fire HD 10 Kids Edition Tablet (32 GB); $130 (save $70)

- Apple iPad Mini (64 GB); $335 (save $64)

- Vankyo MatrixPad S2 Tablet; $120 (save $10)

Tech, gadgets, and TVs

Apple/Amazon

- Apple Watch Series 3 with GPS; $120 (save $79)

- Seneo Wireless Charger, 3 in 1 Wireless Charging Station; $16 (save $10)

- SAMSUNG 75-inch Class Crystal 4K Smart TV; $998 (save $200)

- Nixplay 2K Smart Digital Picture Frame 9.7 Inch Silver; $238 (save $92)

- All-New Amazon Echo Dot with Clock and Alexa (4th Gen); $39 (save $21)

- MACTREM LED Ring Light 6" with Tripod Stand; $16 (save $3)

- Amazon Fire TV Stick with Alexa Voice Remote; $28 (save $12)

- DR. J Professional HI-04 Mini Projector; $93 (save $37)

Headphones and speakers

Beats/Amazon

- Beats Solo3 Wireless On-Ear Headphones; $120 (Save $80)

- Apple AirPods Pro; $169 (save $50)

- Anker Soundcore Upgraded Bluetooth Speaker; $22 (save $8)

- Powerbeats Pro Wireless Earphones; $175 (save $75)

- JBL Boombox; $280 (save $120)

Movies and TV

HBO/Amazon

- Game of Thrones: The Complete Series; $115 (save $89)

- Jurassic World 5-Movie Set; $23 (save $37)

- Deadwood: The Complete Series; $42 (save $28)

- Back to the Future Trilogy; $15 (save $21)

Toys and Games

Amazon

- Awkward Family Photos Greatest Hits; $15 (save $10)

- Exploding Kittens Card Game; $10 (save $10)

- Cards Against Humanity: Hidden Gems Bundle; $14 (save $5)

- LOL Surprise OMG Remix Pop B.B. Fashion Doll; $29 (save $6)

- LEGO Ideas Ship in a Bottle 92177 Expert Building Kit; $56 (save $14)

Furniture

Casper/Amazon

- Casper Sleep Element Queen Mattress; $476 (save $119)

- ZINUS Alexis Deluxe Wood Platform Bed Frame; $135 (save $24)

- ROMOON Dresser Organizer with 5 Drawers; $59 (save $11) 

- AmazonBasics Room Darkening Blackout Window Curtains; $26 (save $5)

- Writing Desk by Caffoz; $119 (save $21)

- SPACE Seating Office Support Managers Chair; $112 (save $116)

- Rivet Globe Stick Table Lamp; $53 (save $17)

- Christopher Knight Home Merel Mid-Century Modern Club Chair; $188 (save $10)

- Walker Edison Furniture Industrial Rectangular Coffee Table; $121 (save $48)

Beauty

Haus/Amazon

- MySmile Teeth Whitening Kit with LED Light; $21 (save $12) 

- Cliganic USDA Organic Lip Balms Set of Six; $6 (save $4)

- HAUS LABORATORIES By Lady Gaga: LE RIOT LIP GLOSS; $7 (save $11)

- Native Deodorant for Men and Women Set of Three; $25 (save $11) 

- BAIMEI Rose Quartz Jade Roller & Gua Sha; $14 (save $3)

- Honest Beauty Clearing Night Serum with Pure Retinol and Salicylic Acid; $20 (save $8)

- WOW Apple Cider Vinegar Shampoo and Hair Conditioner Set; $30 (save $5) 

- La Roche-Posay Effaclar Purifying Foaming Gel Cleanser; $15 (save $5)

- wet n wild Bretman Rock Shadow Palette; $9 (save $6)

- EltaMD UV Daily Tinted Face Sunscreen Moisturizer with Hyaluronic Acid; $25 (save $6)

Clothes

Ganni/Amazon

- Ganni Women's Crispy Jacquard Dress; $200 (save $86) 

- The Drop Women's Maya Silky Slip Skirt; $36 (save $9)

- Steve Madden Women's Editor Boot; $80 (save $30)

- adidas Women's Roguera Cross Trainer; $40 (save $25)

- Line & Dot Women's Elizabeth Sweater; $74 (save $18)

- Levi's Men's Sherpa Trucker Jacket; $57 (save $41)

- Adidas Men's Essentials 3-Stripes Tapered Training Joggers Sweatpants; $28 (save $12)

- Timex Men's Weekender XL 43mm Watch; $32 (save $20)

- Ray-Ban Unisex-Adult Hexagonal Flat Lenses Sunglasses; $108 (save $46) 

- Reebok Men's Flashfilm Train Cross Trainer; $64 (save $16)

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How Much Is the Earth Worth?

The New York Public Library, Unsplash
The New York Public Library, Unsplash

Our home planet may be the most precious place we know, but it isn't priceless. The Earth's resources and the value it offers to humans add up to some unknown, tangible cost. The species may never have to worry about buying or selling the world, but thinking of it in terms of concrete numbers can help us better understand its value. Now, as Treehugger reports, one scientist has developed a special formula that allows us to do just that.

According to the calculations of Greg Laughlin, an assistant astronomy and astrophysics professor from the University of California, Santa Cruz, the Earth is worth roughly $5 quadrillion (or $5,000,000,000,000,000). He came up with that price after gauging the planet's mass, temperature, age, and other factors that directly correlate to its ability to sustain life.

To emphasize just how valuable the Earth is, Laughlin also estimated the worth of other planets in our solar system. Our nearest neighbor Mars costs about the same as a used car at $16,000. That's a fortune compared to Venus, which he appraised at the meager value of one cent.

Laughlin doesn't expect these numbers to have applications in the real world. Rather, he hopes they will inspire people to better appreciate the only home they know. He's not the first person to put a massive, hypothetical price tag on something just for fun. The cost of the Death Star from Star Wars has been calculated at $852 quadrillion—many times Laughlin's estimate for Earth.

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