
Our universe is filled with an infinite amount of unexplained mysteries yet to be explored.
And yet, the limited number of substantive facts we are cognizant of still continue to baffle us.
For instance, did you know the Eiffel Tower can be 15 cm taller in the summer because of thermal expansion? Or that polar bears are nearly undetectable by infrared cameras due to the thickness of their coat and skin?
But along with those rather "cool" facts, there are just as many that are truly unsettling.
Curious to find out what facts can give you the heebie-jeebies, Redditor aelmnnor asked:
"What's a scientific fact that creeps you out?"

Creepy Species
If you apply these entities' characteristics towards human beings, you will have the makings of a horror movie.
Goodbye Siblings
"Obligate siblicide. In some species of animals, multiple offspring are born but only one is actually raised by the mother. The others are born only as backup in case the first-born doesn't survive. When the first-born is fine, which is the typical case, it kills the others."
"Body Horror Lump Of Meat"
"Honestly nothing is more creepy than how deep sea anglerfish mate."
"The deep sea is dark, and the anglerfish are spread very thinly. Therefore, when an anglerfish meets another anglerfish, it's incredibly important they get the chance to mate over and over again. The evolutionary strategy that deep sea anglerfish devised is extra creepy. The male latches onto the female, biting her and never letting go. That way he can inseminate the eggs she drops. Not that bad so far right? But wait, how does he eat if he's latched on his mate?"
"Well, the circulatory systems fuse and the female provides nutrients for the male through this fused circulatory system. The true horror starts here. The organs of male start to wither and atrophy, being absorbed into the female. Eventually, the male is reduced to a lump of testicles the females use to fertilize their eggs. Females are often covered in bumps of several males that have melted into the female, becoming a literal body horror lump of meat on the female."
Stomach This
"Sea stars eject their stomachs to cover edible parts of their prey, begin digesting it externally, and then pull the partially digested prey into digestive glands to finish the job."
The Eternal Void
"Rogue black holes. There are black holes that just are floating around in space and potentially f'king up solar system just by passing through it."
– Xiagax
Plants Are Weird
"That so many vegetables came from the same plant. Broccoli, kale, kohlrabi, Brussels sprouts, cabbage, etc. They are, botanically speaking, the same species. Humans have just bred them to emphasize different traits (buds, leaves, tubers...) Imagine if humans were as genetically flexible. Imagine a person walking around with GIANT toes, but otherwise normal. Actually, plant genetics in general is a weird, weird world."
A Persistent Virus
"Doctors/ scientists are BARELY keeping up with the influenza virus. It keeps on mutating rapidly. It really wants to get inside you."
– [deleted]
Goo-bye
"Caterpillars turn completely into goo in their cocoon, and then become a butterfly."
"And there is evidence they retain memories from their pre-goo days. Memories of strong positive/negative stimuli that they show preference-for/aversion-to, even after metamorphosis."
Our Body Is A Wonderland
Our soul occupies a shell that is a community of tons of other autonomous elements. We truly are merely passengers. Go ahead, ask your brain.
Body Language
"A fever is your body way of saying:"
"We dont negotiate with terrorists! We either destroy the enemy or we die with them!"
– Knork14
Following Our Brains
"Your brain is making decisions before you are even aware of the decisions it has made. It also makes decisions based off of learned behavior and you just go along with it."
Always Being Punk'd
"The brain can play tricks on you:"
"When you look at a clock and the second hand seems to freeze for a moment, your brain is actually generating a false memory - and your perception of time stretches slightly backward."
"This effect is called chronostasis."
Why Do Our Faces Itch? This
"That there are little crab-like things crawling on your face."
Take A Breather
"Thinking about how breathing and lungs work freaks me out. Once I start thinking about it all I can think about is my breathing and then I have to force myself to stop thinking about it."
DNA Mutations
"Some mutations of just one letter in the DNA code can kill the fetus almost instantly, but some people live and have a seemingly healthy life while missing a whole chromosome. If you understand anything about biology, that's completely wild."
Invisible Light
"Humans are bioluminescent (nothing to do with body temperature). We emit visible light that can be photographed in specific conditions. But, this light isn't visible to us. Which makes it a strange thing to have evolved, and begs the question"
"what organisms is this light visible to, and why?"
"Edit: Adding an edit for all the comments explaining evolution... Please read the thread before commenting. I find this a creepy fact due to implications on interspecific relationships, NOT because I think prehistoric humans went shopping for a bioluminescent hat with a specific motive in mind."
Our Breathing Apparatus
"Thinking about how breathing and lungs work freaks me out. Once I start thinking about it all I can think about is my breathing and then I have to force myself to stop thinking about it."
Ominous
Hints of death abound in these unsettling facts.
Tragic Remains
"When the titanic sank non of the shoes decomposed so there's tons of shoes at the bottom of the ocean."
– Dref27
This Sucks
"There is something called 'the squeeze,' where when people had old scuba suits with tubes, you could actually get sucked into that tube if the pressure was off. You are literally shredded through your own breathing tube."
The Urge
"The sudden urge to jump off of a very high height. You can be physically and mentally stable to the greatest degree and still have this feeling when at such a high height."
Always In Battle
"You get and cure cancer in your own body thousands of times a day....."
"Your body produces thousands and thousands of cells with damaged dna. It's a bit of exaggeration to call them cancer but if any of these cells were to survive they could become cancerous. Your immune system destroys them before they get to that point. This is also why if you were to live forever you would eventually get cancer because the chances of your body missing them statistically increases. This occurs thousands upon thousands upon thousands of times a day."
Based on the factoids that just invaded your brain, truth is sometimes stranger than fiction.
One factoid that kept me up at night was reading about a woman in 2015 who suffered from headaches. It turned out the source was a brain tumor – one that resembled skin and had bones, teeth, and hair.
The rare mass was called a "teratoma," and doctors confirmed it was not a "twin," but germ cells that had fallen off when the woman was an embryo and wound up on an abnormal place – her brain – and continued to develop along with her.
If the woman heard voices in her head – as some of us figuratively experience – it might have literally been because she had a mouthpiece growing inside her brain.
Ahh, the mysteries of life.
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Advancements in science happen every day in every way.
But often it feels like we are still so far behind.
How have we not cured so many diseases?
Shouldn't we know more about space?
What is Jello really made of?
So much to ponder and understand.
Maybe one day.
We all have a bucket list of what we'd like to see cured or invented before our last breaths.
Let's discuss...
Redditor yoda2060wanted to discuss all the science that needs to be devoured before the sand runs out of the hourglass. They asked:
"What scientific achievement you would like to see before you die?"
Life is infinite and we'll never know everything that is possible. But let's dream of what could be...
New pieces...
"I want to see us grow hearts, kidneys, livers, etc... In labs and end the need for donations and waiting lists for transplants."
IMadeThisBullS*itUp
"I waited for a heart/bilateral lung transplant for over a year and I spent 8 months living in the hospital waiting for it. You’re basically waiting for someone to die."
"Which feels all kinds of wrong… but my therapist (all transplant patients sees a transplant therapist) kept reminding me that me needing a heart and lungs doesn’t cause someone to die…"
"And what made even harder was that my mom died of Covid about 5 weeks before my transplant happened. So while I was praying and hoping so hard my mom wouldn’t die… I was also praying for my transplant to happen. I had a lot of mixed and confusing feelings. My transplant happened last November."
Junebug1515
"Idiot Bottom Line"
"To build an environment friendly world."
deadprotocol_
"That depends entirely on how far you want to go with 'environmentally friendly.' Some amateurish pseudo-intellectuals will say that humanity itself is devastating the planet by it's very existence so we'll call that the 'Idiot Bottom Line."'
"So you have to find an acceptable level above that to declare environmentally friendly. For example can we still have hear exchangers? Space debris? Artificial Electromagnetic radiation? There has to be a level before you can declare such and so far no one agrees."
PoorPDOP86
“20 years, tops”
"Viable nuclear fusion."
AlterEdward
"Nuclear Astrophysicist here. I know the joke is that we been saying '20 years, tops' for 50 years now - who do you think came up with that joke? But seriously, we are really close."
"We need a reaction that is self-sustaining and puts out more energy than we put in. We can easily do a reaction that’s one or the other, just getting one that’s both is hard. And with recent updates to the Greenwald limit we found some relatively minor tweaks that doubles previous theoretical max output."
Gleeful-Nihilist
Deep Within
"Figuring out what Dark Matter is, solving the mysteries of black holes. Proper thorough investigation of our own oceans."
fIumpf
So far, so interesting. We have so much to learn.
let me dream...
"Prosthetic limbs and organs that can work just as well as real ones. Affordably too. A cure for total nerve damage. Carbon neutral liquid fuel. FTL travel (let me dream)."
idonthaveanaccountA
Contact
"Making contact with another intelligent species in another solar system."
Pigs100
"That's probably not going to happen. I'd be overjoyed though if we discovered even just microbial life in the oceans of Europa or Enceladus. They'd be the first true extra-terrestrials ever encountered."
Cybyss
Going Places
"If we had teleports then we might also have other technologies integrated with it like instant dental work, instant food, instant surgery, things just unthinkable without the technology but before the steam engine travel was by horse so they could not imagine traveling cross country in any other way besides ships. Maybe with teleports we wouldn't need energy, just an infinite loop of the first spark."
Stickerdan
Sickness be gone...
"Cure for all cancer forms."
Kal-El1994
"I approached a nursing assistant with the question. They could describe it as trying to go after the stick of a lollipop. The treatments are mostly concerned with favors, not sticks. If they can discover a way to deal with the stick, then you may be able to treat cancer from there."
MissSara101
"I think it is important to add that there won’t be ONE cure to all cancers. Cancer is such a broad spectrum of diseases that sometimes have next to nothing in common. But hopefully we will keep getting the survival rates up with different medications for different cancer types."
TastyConsideration82
Simplicity
"Solve back pain please. We can do crazy sh*t like nuclear bombs, new fancy vaccines and space exploration, yet we don't have a solution to one of the biggest and most common ailments that existed though all of humanity."
inksane
I want to see all of this happen! Fingers crossed.
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Fast fashion is terrible for the environment, one of the largest polluters of clean water globally because of its all too common use of cheap, toxic textile dyes.
It also places producers under more and more pressure to manufacture more and more clothes on masse–the people working in the factories that make this stuff are being paid a pittance, contributing to much of the wealth inequality in less developed nations.
Additionally, it's estimated that the textiles industry produces 1.2 billion tonnes of CO2 per year and that just two percent of all fast fashion emissions can be reduced through recycling. Ouch. Time to change habits, right?
People shared their thoughts on this and other topics after Redditor urmomsucked asked the online community,
"What should people seriously stop buying?"
"Pets..."
"Pets they can’t take care of."
WonderfulShop888
I have known several people who got puppies, decided they couldn't handle them, and dumped them. It's rage-inducing.
"Nestle products."
"Nestle products. Literally the most evil company currently in business. Unfortunately it's really hard to tell what brands they own."
I_used_to_be_hip
Nestle is responsible for the deaths of babies in undeveloped nations. It's sick.
"Designer clothes..."
"Designer clothes and accessories with logos slapped all over them. It wastes your money and makes you look idiotic."
Botryoild2000
The funny thing is, the designer clothes/accessories with logos slapped all over them are typically the cheapest options from said designer.
"Simple syrup."
"Simple syrup. It’s sugar water with an $8 price tag."
providentialchief
It's easy enough to make your own. Your iced tea will never be the same again.
"Cheap belts."
"Cheap belts. A quality leather belt will last you decades."
[deleted]
I have a few (quality leather belts, that is) and they've lasted for years and years. Can confirm.
"Cigarettes."
"Cigarettes. To anyone reading this, please just don't start even if it's out of curiosity. I'm 20 years deep into this and it's hell."
SeaSwimmer5386
Smoking is a brutal addiction to break. The Food and Drug Administration (FDA) recently proposed rules prohibiting menthol cigarettes and flavored cigars to stop young people from picking up the habit.
"Garment workers..."
"Fast fashion. Garment workers get paid s*it, the environment suffers and you look like everybody else on the street with no personality or sense of individualism."
SenoritaBrownRecluse
This should be up at the top. The environmental impact is terrible.
"Unnecessarily large vehicles..."
"Unnecessarily large vehicles, which they'll then inevitably complain cost too much to fill the gas tank."
[deleted]
Gas guzzlers need to go. It's far past time that they be phased out.
"Anything advertised..."
"Anything advertised on Instagram. It’s a scam and those influencers are just making it look cheap AF."
megapintt
Or just avoid Instagram in general. That would solve a lot.
"New phones..."
"New phones when their current is just as good."
[deleted]
You've got that right. People buy a new one for the hell of it without even thinking about it.
It's pretty clear that many of us need to change our habits now. Our wallets will thank us later.
Have some suggestions of your own? Feel free to tell us more in the comments below!
If you make too many funny faces, your face will stay that way permanently.
Watch too much tv and your eyes will fall out.
Break a mirror and it's seven years of bad luck.
These are among the many myths and superstitions we heard as children, more often than not from our parents and teachers as a way of scaring us into behaving.
But while there is not one ounce of truth to any of these tall tales, there are many who still believe them, and many more.
Redditor RedditPersonIf was curious to learn what superstitions people continue to believe are true, leading them to ask:
"What myths are obviously false, yet most people still believe they are true?"
When they fly the coop...
"If you take care of a baby bird, the mother won’t want it anymore because it’ll smell like a human."- GreatXs
No amount of fiber can help you
"If you swallow gum, it'll stay in your digestive tract for 7 years."- stinky_cheese33
It was every other subjects he had trouble with
"Albert Einstein failed math in school."- Nothingreallyend
Though it does make shampooing easier
"Shaving your hair will make the hair grow back thicker.'- RunWithScissorsss
Sleep with your mouth closed
"The amount of spiders you eat while being asleep."- pantsofafatman
Just... No...
"That you are supposed to pee on a jellyfish sting to ease the pain."- Actuaryba
Olé
"Bulls not liking the color red."
"Bulls are partially color blind and can only see yellow, green, blue, and violet."- Rogurzz
Call a Lyft instead
"Coffee, speed, and uppers sober you up."
"Nope!"
"Too drunk to drive?"
"Now you're drunk AND on drugs, you just don't feel the effects of the booze but your motor skills, reaction time and decision making are all still drunk AF."- kirkrjordan
Best let nature run its course
"The damn alpha wolf."
"It was one study under captivity, the poor researcher made it his life's work to try and set it right."
"If you want a brutal hierarchy where everyone pecks down, what you're looking for is chickens."- raxeira-etterath
Give this one some thought
"We can only use 10% of our brain."- UnbearableHuman
A little bit of research will clear up any doubt you have on these old superstitions and beliefs.
And for anyone who helped out a friend who got stung by a jellyfish, no need to be embarrassed.
Who hasn't looked at a scarf someone knitted for a loved one, a flawless homemade birthday cake, or an immaculately planted garden and thought, "I wish I could do that"?
But you'd never dare try to attempt it yourself, knowing that it's well beyond your personal skill set.
But is it?
Intimidating as they may seem, some skills might be deceptively easier than they appear to be, or might come more naturally to you than to many others.
Redditor halfmoon599 was curious to hear what skills people believed to be much easier than they seem, leading them to ask:
"What skill is actually easier to learn than what other people think?"
Everyone can be ambidextrous!
"I'm left handed and and I wanted to learn to write with my right hand."
"it was much easier than I thought and now I can write with it making it look somewhat decent."- JE3V4N_
"Using your off hand skillfully."
"I worked on this when I owned a woodworking business and it has helped so many times over the years."- karg_the_fergus
Should you ever forget your keys...
"Picking a lock."
"It only takes about 1 or 2 hours to learn, contrary to popular belief." - DifficultAd5113
Can't get to the genius stand? No problem!
"Fixing computers."
"It's just a lot of googling and YouTubing."- theassassintherapist
"Basic IT troubleshooting."- usmarine7041
You'll have a blanket done in no time!
"Crocheting!"
"It looked really difficult to me but I was really pleased how easy it was to pick up."
"Especially with YouTube tutorials."- geeltulpen
But do get a license first...
"Flying a small airplane is actually very simple."
"It's everything else like weather and flight planning, emergency mindfulness, airspace and traffic, and confidence in yourself that gets tricky, but any person with eyeballs and a pulse could fly a plane."- Clyde-MacTavish
With practice, of course
"Parallel parking."- Feels2old
Give your arms a rest!
"Unicycling."
"It takes just 10-20 minutes a day for 3-10 days.'
"Find a railing you can lean on to start."
"At some point, you'll be able to let go and ride!'- Vegan_BTW_VR
... Is it though?...
"Driving a stick shift."- fantazja1
Next time you think, "aw, I wish I could do that," rather than keep wishing, why not just give it a try?