11 Insightful Facts About Eyes

iStock.com/Paffy69
iStock.com/Paffy69

There are a lot of myths and misconceptions about the eyes. No, sitting too close to the TV won't damage your vision, and reading in dim light won’t hurt either. It’s understandable that various parts of the eye are so little understood, though. Each eye has more than a million optic nerve cells and over 106 million photoreceptor cells, making it one of the most complex organs we have. Here are a few more things you should know about your “windows to the soul.”

1. Newborn babies see the world in black and white—and red.

“It is a myth that babies see in black and white,” Anna Franklin, leader of the University of Sussex's Baby Lab, told The Guardian. While newborns do see black, white, and shades of gray, they can also detect red objects against a gray backdrop, Franklin says. The reason why they can’t see more colors is because the cones in their eyes—the photoreceptor cells responsible for picking up colors—are too weak to detect them. Those cells quickly get stronger, though. After about two months, babies can distinguish between red and green, and a few weeks later they can tell the difference between blue and yellow.

2. Your eyeballs grow as you age.

Another common misconception is that your eyes remain the same size from birth to adulthood. As a newborn, your eyes measure about three-fifths of an inch from front to back, compared to a little under an inch in adults. Your eyes actually grow a great deal in the first two years of life, and another growth spurt occurs when you go through puberty. The confusion likely stems from the fact that your eyes as a 6-month-old infant are two-thirds the size they will be when you’re an adult.

3. The length of your eye partly determines how well you'll be able to see.

If your eyeball is too long or too short, you might end up having problems with your vision. Nearsighted people have eyes that are longer than average, while farsighted people have eyes that come up a little short. If you were to magically add or remove a millimeter of length from your eye, it would completely change your prescription. Aside from eye length, the shape of your cornea (the outer part of the eye where contact lenses are placed) and lens (the part of the eye located behind the iris and pupil) are other key factors that determine the quality of your vision. That's because both of these parts work together to refract light.

4. Contact lenses can't really get lost behind your eye.

Although it may feel like a dislodged contact lens is stuck behind your eye, that isn’t exactly what’s happening. The thin membrane covering the white part of your eye and the underside of your eyelid—called the conjunctiva—forms a pouch and prevents objects from getting behind your eyeball. If a contact lens gets shifted out of place to the point where you can no longer see it, it’s just stuck underneath your upper eyelid, which isn’t nearly as scary.

5. Blue-eyed people share a common ancestor.

Originally, everyone in the world had brown eyes. It wasn’t until around 6000 to 10,000 years ago that the first blue-eyed person was born as a result of a genetic mutation, according to a 2008 study. That mutation of the OCA2 gene essentially “turned off the ability to produce brown eyes” and diluted the color to blue, Professor Hans Eiberg of the University of Copenhagen said in a statement.

6. Parts of the eye can get sunburned.

There’s a good reason you should wear sunglasses when it’s bright outside. Too much exposure to UV rays can damage the surface of the cornea and conjunctiva, causing a condition akin to sunburn called photokeratitis. Symptoms include pain, red or swollen eyes, the sensation of a foreign body in the eyes, blurred vision, headaches, and seeing halos around lights. While the discomfort is temporary and tends to go away within 48 hours, longer exposure to UV rays can have a long-term effect on your vision and lead to macular degeneration (deterioration of the retina, which is often age-related) and cataracts (clouding of the eye's lens, which reduces the amount of light coming in).

7. Your eye muscles are the fastest muscle in your body.

Extraocular muscles are what let you look around in all directions. You have six of these muscles in each eye, and many of the motions they make are involuntary. This lets you flick your eyes to one side and notice something in your peripheral vision without consciously looking in that direction. When both of your eyes move in the same direction, the movement is called a saccade, which comes from the French word for “jerk” (the verb, not the person). These jerky movements are extremely rapid, lasting about 50 to 60 milliseconds per saccade, according to Dr. Reza Shadmehr, professor of biomedical engineering and neuroscience at Johns Hopkins University. “Saccadic eye movements are the fastest voluntary movements that we can make. The eyes move at around 500 degrees per second or more,” Shadmehr tells Mental Floss.

8. Your eye movements might give away your next move.

Shadmehr and other researchers conducted an experiment in 2015 to test the relationship between saccades and decision-making. Participants were placed in front of a computer and asked to choose between two options that appeared on the screen: an immediate reward and a delayed reward. For instance, one option might be “get $10 today,” while the other might be “wait 30 days and get $30.” Their eye movements were tracked the entire time, and researchers discovered that these movements gave away the choice they were about to make before they made it. At the last minute, their eyes would move at a faster velocity towards the option that they preferred.

“What’s interesting is that as the saccades are being made, the velocity of the eyes starts out being equal between these two stimuli, but then right before you decide ‘I like A better than B,' the saccade that you make toward A has a higher velocity than the one you make toward B,” Shadmehr explains. “The idea is that the way you’re evaluating things is reflected in the way you move toward them.”

In another experiment, Shadmehr found a correlation between faster eye movements and impatient and impulsive behaviors. Similarly, other studies have shown that our eye movements are linked to moral decisions and even our political temperament.

9. You can tell some animals' place in the food chain by looking at a part of their eye.

In 2015, vision scientist Martin Banks and his colleagues looked at the eyes of 214 species in an attempt to answer the question, “Why do animal eyes have pupils of different shapes?” By the end of their study, they noticed a few patterns. Predatory animals like big cats and snakes tend to have pupils in the shape of vertical slits. This particular shape gives them the advantage of being able to accurately judge the distance separating them and their prey, so they'll know exactly how far they have to pounce. On the other hand, horizontal pupils are more common in goats, deer, cattle, and other herbivores. This shape improves an animal’s panoramic vision, which helps them look out for predators.

10. An eye condition may have been partly responsible for Leonardo da Vinci's artistic genius.

Visual neuroscientist Christopher Tyler argued in a recent paper that the master artist behind Mona Lisa had strabismus, a disorder where the eyes are misaligned. Essentially, one of his eyes turned outwards, and he was able to use both of his eyes separately (monocular as opposed to binocular vision). Tyler believes this actually aided his art by improving his ability to render three-dimensional images on a flat canvas. “The condition is rather convenient for a painter, since viewing the world with one eye allows direct comparison with the flat image being drawn or painted,” Tyler said. We’ll never know for sure whether or not this was true for Leonardo, but it’s an intriguing theory.

11. SURGEONS HOPE TO BE PERFORMING WHOLE EYE TRANSPLANTS BY 2026. 

Currently, only cornea transplants to improve vision are possible, but a team of Pittsburgh-based transplant surgeons said in 2016 that they hoped to be performing whole eye transplants in humans within the next decade. Transferring an eye from a deceased donor to a recipient certainly won’t be easy, though. A complicated network of muscles, blood vessels, and nerves connects the eyes to the brain via the optic nerve. However, further studies into the optic nerve and recent advances in immunosuppressive drugs and surgical techniques have brought them several steps closer to achieving this goal. If successful, the surgery could restore vision to people who have suffered severe eye injuries. Their research is backed by the Department of Defense, which is concerned about the number of soldiers who sustain eye injuries in combat.

10 LEGO Sets For Every Type of LEGO Builder 

Amazon
Amazon

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If you’re looking for a timeless gift to give this holiday season, look no further than a LEGO set. With kits that cater to a wide age range—from toddlers fine-tuning their motor skills to adults looking for a more engaged way to relax—there’s a LEGO set out there for everyone. We’ve rounded up some of our favorite sets on Amazon to help you find the LEGO box that will make your loved one smile this year. If you end up getting one for yourself too, don’t worry: we won’t tell.

1. Classic Large Creative Gift Box; $44

Amazon

You can never go wrong with a classic. This 790-piece box contains dozens of types of colored bricks so builders of any age can let their inner architect shine. With toy windows, doors, tires, and tire rims included in addition to traditional bricks, the building possibilities are truly endless. The bricks are compatible with all LEGO construction sets, so builders have the option of creating their own world or building a new addition onto an existing set.

Buy it: Amazon

2. Harry Potter Hogwarts Express; $64

Amazon

Experience the magic of Hogwarts with this buildable Hogwarts Express box. The Prisoner Of Azkaban-inspired kit not only features Hogwarts's signature mode of transportation, but also Platform 9 ¾, a railway bridge, and some of your favorite Harry Potter characters. Once the train is built, the sides and roof can be removed for play within the cars. There is a Dementor on board … but after a few spells cast by Harry and Lupin, the only ride he’ll take is a trip to the naughty list.

Buy it: Amazon

3. Star Wars Battle of Hoth; $160

Amazon

Star Wars fans can go into battle—and rewrite the course of history—by recreating a terrifying AT-AT Walker from the Battle of Hoth. Complete with 1267 pieces to make this a fun challenge for ages 10 and up, the Walker has elements like spring-loaded shooters, a cockpit, and foldout panels to reveal its deadly inner workings. But never fear: Even though the situation might look dire, Luke Skywalker and his thermal detonator are ready to save the day.

Buy it: Amazon

4. Super Mario Adventures Starter Course; $60

Amazon

Kids can play Super Mario in 3D with LEGO’s interactive set. After constructing one of the courses, young designers can turn on the electronic Mario figurine to get started. Mario’s built-in color sensors and LCD screens allow him to express more than 100 different reactions as he travels through the course. He’ll encounter obstacles, collect coins, and avoid Goomba and Bowser to the sound of the Mario soundtrack (played via an included speaker). This is a great gift for encouraging problem-solving and creativity in addition to gaming smarts.

Buy it: Amazon

5. Gingerbread House; $212

Amazon

Gingerbread houses are a great way to enjoy the holidays … but this expert-level kit takes cookie construction to a whole new level. The outside of the LEGO house rotates around to show the interior of a sweet gingerbread family’s home. Although the living room is the standout with its brick light fireplace, the house also has a kitchen, bedroom, bathroom, and outdoor furniture. A LEGO Christmas tree and presents can be laid out as the holidays draw closer, making this a seasonal treat you can enjoy with your family every year.

Buy it: Amazon

6. Elsa and Olaf’s Tea Party; $18

Amazon

LEGO isn’t just for big kids. Toddlers and preschoolers can start their LEGO journey early by constructing an adorable tea party with their favorite Frozen characters. As they set up Elsa and Olaf’s ice seats, house, and tea fixings, they’ll work on fine-motor, visual-spatial, and emotional skills. Building the set from scratch will enable them to put their own creative spin on a favorite movie, and will prepare them for building more complicated sets as they get older.

Buy it: Amazon

7. Collectible Art Set Building Kits; $120

Amazon

Why buy art when you can build it yourself? LEGO’s Beatles and Warhol Marilyn Monroe sets contain four options for LEGO art that can be built and displayed inside your home. Each kit comes with a downloadable soundtrack you can listen to while you build, turning your art experience into a relaxing one. Once you’re finished building your creation it can be exhibited within a LEGO brick frame, with the option to hang it or dismantle it to start on a new piece. If the 1960s aren’t your thing, check out these Sith and Iron Man options.

Buy it: Amazon

8. NASA Apollo Saturn V; $120

Amazon

The sky (or just the contents of your LEGO box) is the limit with LEGO’s Saturn V expert-level kit. Designed for ages 14 and up, this to-scale rocket includes three removable rocket stages, along with a command and service module, Lunar Lander, and more. Once the rocket is complete, two small astronaut figurines can plant a tiny American flag to mark a successful launch. The rocket comes with three stands so it can be displayed after completion, as well as a booklet for learning more about the Apollo moon missions.

Buy it: Amazon

9. The White House; $100

Amazon

Reconstruct the First Family’s home (and one of America’s most famous landmarks) by erecting this display model of the White House. The model, which can be split into three distinct sections, features the Executive Residence, the West Wing, and the East Wing of the complex. Plant lovers can keep an eye out for the colorful rose garden and Jacqueline Kennedy Garden, which flank the Executive Residence. If you’re unable to visit the White House anytime soon, this model is the next best thing.

Buy it: Amazon

10. Volkswagen Camper Van; $120

Amazon

Road trip lovers and camping fanatics alike will love this vintage-inspired camper. Based on the iconic 1962 VW vehicle, LEGO’s camper gets every detail right, from the trademark safari windshield on the outside to the foldable furniture inside. Small details, like a “Make LEGO Models, Not War” LEGO T-shirt and a detailed engine add an authentic touch to the piece. Whether you’re into old car mechanics or simply want to take a trip back in time, this LEGO car will take you on a journey you won’t soon forget.

Buy it: Amazon

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30 Pungent Facts About Farts

This man is clearly not trying to hide the fact he just passed gas.
This man is clearly not trying to hide the fact he just passed gas.
BrilliantEye/iStock via Getty Images

Whether you openly admit it or desperately try to hide it, it’s an undeniable fact that every living and breathing human being farts. And while passing what you thought was going to be silent gas only to be wrong in certain situations can definitely be embarrassing, there’s something undeniably humorous about flatulence—no matter your age.

If you do love a good fart joke, you’re in good company. The very first recorded joke, which was written by the Sumerians and dates all the way back to 1900 BCE, was about—you guessed it—breaking wind. And some of the world's great thinkers, from William Shakespeare to J.D. Salinger, have slipped a fart joke (or 10) into their work.

In this episode of The List Show, we're sniffing out 30 fascinating facts about farts—from why humans expel gas to how often the average adult squeezes the cheese. You can watch the full episode below.

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