19 Every Day Things Science Hasn’t Figured Out

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Haydar Dogramaci/iStock via Getty Images Plus

Science has enabled humans to complete some pretty incredible feats, like land on the moon, for example. But when it comes to common things like laughter or hiccups, scientists still can’t quite figure out the reason behind them. In this article, which was adapted from The List Show on YouTube, we look at everyday things that are still a mystery.

1. It's still not understood why we cry.

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Crying is still a scientific mystery. Physiologically, it’s clear what’s happening when someone cries. But, it has been more difficult to figure out the evolutionary reason for tears. We know that babies cry to communicate and get attention. So, some experts believe that adults might also cry for social reasons, like to bond or to warn others that something is amiss.

2. The reason we laugh is still unknown.

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Like crying, we also don’t know why people evolved the ability to laugh, but experts guess it has something to do with communication—and not just that we find something funny. One researcher found that only 20 percent of laughs he looked at were preceded by anything deemed in any way humorous.

It's possible we laugh to let other people know that we’re okay or to bond with each other. A study published in 2016 gave evidence for the latter. Researchers found that an outside observer could distinguish whether laughter was produced between a pair of strangers or a pair of friends.

3. Scientists haven't figured out why we blush.

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Blushing is often telling others things we don’t want them to know, like the fact that we’ve done something wrong or embarrassing. Some experts believe that we may have evolved blushing to show submission to group leaders. Others think it may have something to do with the fact that blushing people have been shown to be considered more likable, so it helps peers look past the bad things we’ve done.

4. It's still unclear why anesthesia makes us pass out.

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General anesthesia has been in use in the United States since 1846, but there are still some uncertainties about why the chemicals in anesthetics cause people to pass out. A recent study showed that the drugs affect proteins in the brain and the reason we go unconscious has to do with altering neural activity, but more research is needed.

5. We aren't exactly sure what consciousness is.

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Consciousness is frequently defined as how we feel present and alive in the world. But the question is: Why and how do we feel conscious? It’s of interest in both philosophy and science. Scientists would like to know which part of the brain is responsible for consciousness, but it’s still a mystery.

6. It's unclear exactly how medications like Tylenol work.

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We don’t 100 percent understand how pain relievers containing acetaminophen give us pain relief. We do know that acetaminophens aren’t totally consistent; they’re more effective in some types of cells than in others. So for now, scientists believe the drugs might be a specific type of enzyme inhibitor.

7. We aren't sure why we get hiccups or how to stop them.

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Scientists don’t know what causes hiccups, what purpose they serve, or how to cure them. A lot of people have favorite techniques, from gargling water to pulling hard on the tongue, but there’s no scientifically-proven way to get rid of them.

In 2002, one researcher tried to get to the bottom of the problem by looking at how 54 hospital patients had been treated for hiccups. They tried multiple treatments, like holding their breath and medication, but none were proven effective.

8. Scientists haven't figured out why tornadoes start.

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We don’t know why only some thunderstorms create tornadoes and others don’t. Generally, it’s understood that tornadoes come to be when cold, dry air interacts with warm, humid air. But the thunderstorms that result from those air conditions only sometimes cause tornadoes.

9. Scientists also haven't figured out why tornadoes end.

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It’s also unclear why tornadoes die—though experts believe that at least sometimes it has to do with the tornado’s interaction with cold temperatures.

10. It's still uncertain why we need to sleep.

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There are theories as to why we need sleep, but no one knows for sure. It's possible our ancestors slept because it kept them out of danger during the night. Or it could be an energy conserving function. What we do know is that sleep helps us recover from the day, and there’s evidence it changes the connections in our brains.

11. The reason we dream is still unclear.

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Similarly, there are no clear answers as to why we dream. Some sleep experts think dreaming doesn’t have a purpose at all. Others have theories, like that we’re playing out threatening situations, like being chased, so that we’re better equipped to handle danger while awake.

12. We still aren't sure why we have the urge to scratch.

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We often understand why we itch. But, we don’t completely understand why we have the urge to scratch. The body has receptors just for itches that are almost identical to those that convey pain, and it’s thought that scratching might interfere with these signals. But at the same time, it might cause the skin to get more irritated, which causes even more itching.

13. Science still hasn't figured out the cure for aging.

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Scientists know some things about why we age, but no one has fully figured it out. There’s little evidence for popular hypotheses having to do with things like free radicals and telomeres. Aging is probably the result of a complex group of poorly understood processes, meaning a cure isn’t happening any time soon.

14. Ornithologists still don't know why only some birds migrate.

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It’s also unclear why some birds migrate while others don’t. The ones that do migrate might do it to conserve energy, which might be kind of confusing, since they’re flying great distances and therefore expending a lot of energy to get to their destination. But it’s likely worth it since they’re probably traveling somewhere with abundant energy sources—a.k.a., plenty of available food. Luckily, thanks to technology like tracking devices, scientists are able to track birds more easily and are now learning much more about migration.

15. Scientists haven't figured out the “nature vs. nurture” debate.

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The question of nature versus nurture hasn’t been settled yet. Technically, we know that our genes interact with our environment to foster characteristics—but science isn’t sure to what extent. A complicating factor is that it varies by trait and individual person. How much your genes are influencing your IQ, for instance, may be different from someone else.

16. We still aren't sure why the placebo effect happens.

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The placebo effect is pretty mysterious. It has been proven again and again that sugar pills and other fake treatments can actually make someone feel better. And it’s not just a feeling as scans have shown that placebos affect the area of the brain associated with pain. We still don’t know why. It’s believed that placebos somehow help release endorphins, but experts need more information.

17. It's still unclear why bicycles are able to stay up on their own.

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Have you ever given a bike with no one on it a push and noticed that it stays up on its own? It doesn’t fall over for much longer than you expect, and we don’t know how it manages to balance itself while moving.

18. How skates work on ice is still unknown.

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And another mystery of physics: How do skates work on ice? There is a popular theory. We know that ice has a very thin layer of liquid on it. So, a skate moving quickly on top of ice might make more liquid because the friction causes melting. The skate is actually changing the ice itself, creating a path on which to glide.

19. There still isn't a cure for the common cold.

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We get colds from seven separate families of viruses and those families have sub-viruses. So, to cure the “cold,” there would need to be a cure that acts as a catch-all for about 200 sub-viruses.

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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10 Facts About Real Genius On Its 35th Anniversary

Val Kilmer stars in Martha Coolidge's Real Genius (1985).
Val Kilmer stars in Martha Coolidge's Real Genius (1985).
Sony Pictures Home Entertainment

In an era where nerd is a nickname given by and to people who have pretty much any passing interest in popular culture, it’s hard to imagine the way old-school nerds—people with serious and socially-debilitating obsessions—were once ostracized. Computers, progressive rock, and role-playing games (among a handful of other 1970s- early '80s developments) created a path from which far too many of the lonely, awkward, and conventionally undateable would never return. But in the 1980s, movies transformed these oddballs into underdogs and antiheroes, pitting them against attractive, moneyed, successful adversaries for the fate of handsome boys and pretty girls, cushy jobs, and first-place trophies.

The 1985 film Real Genius ranked first among equals from that decade for its stellar cast, sensitive direction, and genuine nerd bona fides. Perhaps fittingly, it sometimes feels overshadowed, and even forgotten, next to broader, bawdier (and certainly now, more problematic) films from the era like Revenge of the Nerds and Weird Science. But director Martha Coolidge delivered a classic slobs-versus-snobs adventure that manages to view the academically gifted and socially maladjusted with a greater degree of understanding and compassion while still delivering plenty of good-natured humor.

As the movie commemorates its 35th anniversary, we're looking back at the little details and painstaking efforts that make it such an enduring portrait not just of ‘80s comedy, but of nerdom itself.

1. Producer Brian Grazer wanted Valley Girl director Martha Coolidge to direct Real Genius. She wasn’t sure she wanted to.

Following the commercial success of 1984’s Revenge of the Nerds, there was an influx of bawdy scripts that played upon the same idea, and Real Genius was one of them. In 2011, Coolidge told Kickin’ It Old School that the original script for Real Genius "had a lot of penis and scatological jokes," and she wasn't interested in directing a raunchy Nerds knock-off. So producer Brian Grazer enlisted PJ Torokvei (SCTV) and writing partners Babaloo Mandel and Lowell Ganz (Splash, City Slickers) to refine the original screenplay, and then gave Coolidge herself an opportunity to polish it before production started. “Brian's original goal, and mine, was to make a film that focused on nerds as heroes," Coolidge said. "It was ahead of its time."

2. Martha Coolidge’s priority was getting the science in Real Genius right—or at least as right as possible.

In the film, ambitious professor Jerry Hathaway (William Atherton) recruits high-achieving students at the fictional Pacific Technical University (inspired by Caltech) to design and build a laser capable of hitting a human-sized target from space. Coolidge researched the subject thoroughly, working with academic, scientific, and military technicians to ensure that as many of the script and story's elements were correct. Moreover, she ensured that the dialogue would hold up to some scrutiny, even if building a laser of the film’s dimensions wasn’t realistic (and still isn’t today).

3. One element of Real Genius that Martha Coolidge didn’t base on real events turned out to be truer than expected.

From the beginning, the idea that students were actively being exploited by their teacher to develop government technology was always fictional. But Coolidge learned that art and life share more in common than she knew at the time. “I have had so many letters since I made Real Genius from people who said, 'Yes, I was involved in a program and I didn’t realize I was developing weapons,'" she told Uproxx in 2015. “So it was a good guess and turned out to be quite accurate.”

4. Val Kilmer walked into his Real Genius audition already in character—and it nearly cost him the role.

After playing the lead in Top Secret!, Val Kilmer was firmly on Hollywood’s radar. But when he met Grazer at his audition for Real Genius, Kilmer decided to have some fun at the expense of the guy who would decide whether or not he’d get the part. "The character wasn't polite," Kilmer recalled to Entertainment Weekly in 1995. "So when I shook Grazer's hand and he said, 'Hi, I'm the producer,' I said, 'I'm sorry. You look like you're 12 years old. I like to work with men.'"

5. The filmmakers briefly considered using an actual “real genius” to star in Real Genius.

Among the performers considered to play Mitch, the wunderkind student who sets the movie’s story in motion, was a true genius who graduated college at 14 and was starting law school. Late in the casting process, they found their Mitch in Gabriel Jarrett, who becomes the third generation of overachievers (after Kilmer’s Chris and Jon Gries’s Lazlo Hollyfeld) whose talent Hathaway uses to further his own professional goals.

6. Real Genius's female lead inadvertently created a legacy for her character that would continue in animated form.

Michelle Meyrink, Gabriel Jarret, Val Kilmer, and Mark Kamiyama in Real Genius (1985).Sony Pictures Home Entertainment

Michelle Meyrink was a staple of a number of ‘80s comedies, including Revenge of the Nerds. Playing Jordan in Real Genius, she claims to “never sleep” and offers a delightful portrait of high-functioning attention-deficit disorder with a chipper, erratic personality. Disney’s Chip 'n Dale: Rescue Rangers co-creator Tad Stones has confirmed that her character went on to inspire the character of Gadget Hackwrench.

7. A Real Genius subplot, where a computer programmer is gaming a Frito-Lay contest, was based on real events.

In the film, Jon Gries (Napoleon Dynamite) plays Lazlo Hollyfeld, a reclusive genius from before Chris and Mitch’s time who lives in a bunker beneath their dorm creating entries to a contest with no restrictions where he eventually wins more than 30 percent of the prizes. In 1969, students from Caltech tried a similar tactic with Frito-Lay to game the odds. But in 1975, three computer programmers used an IBM to generate 1.2 million entries in a contest for McDonald’s, where they received 20 percent of the prizes (and a lot of complaints from customers) for their effort.

8. One of Real Genius's cast members went on to write another tribute to nerds a decade later.

Dean Devlin, who co-wrote Stargate and Independence Day with Roland Emmerich, plays Milton, another student at Pacific Tech who experiences a memorable meltdown in the rush up to finals.

9. The popcorn gag that ends Real Genius isn’t really possible, but they used real popcorn to simulate it.

At the end of the film, Chris and Mitch build a giant Jiffy Pop pack that the laser unleashes after they redirect its targeting system. The resulting popcorn fills Professor Hathaway’s house as an act of revenge. MythBusters took pains to recreate this gag in a number of ways, but quickly discovered that it wouldn’t work; even at scale, the popcorn just burns in the heat of a laser.

To pull off the scene in the film, Coolidge said that the production had people popping corn for six weeks of filming in order to get enough for the finale. After that, they had to build a house that they could manipulate with hydraulics so that the popcorn would “explode” out of every doorway and window.

10. Real Genius was the first movie to be promoted on the internet.

A week before Real Genius opened, promoters set up a press conference at a computer store in Westwood, California. Coolidge and members of the cast appeared to field questions from press from across the country—connected via CompuServe. Though the experience was evidently marred by technical problems (this was the mid-1980s, after all), the event marked the debut of what became the online roundtable junket.