We all have a concept of reality. We know what is “fact” and what isn’t. However, the truth of the matter is that the definition of “real” is a mere construct of the brain.
If that didn’t blow your mind, this list has a lot more where that came from. These are responses from a recent Reddit thread, bearing a question originally directed at scientists: “What’s something we know is true but people don’t realize how crazy it is?”
A lot of these answers did not disappoint. You may want to have Google open next to you as you read through, since you'll likely want to do a little more digging.
#1

Charles Keeling had a team at Mauna Loa Observatory taking twice-daily samples of the air since 1958, specifically to test for CO2. As you can imagine, this was was done by a dude bringing a jar out, holding their breath, opening the jar, waving it around, putting back on the lid, then resuming their breathing. Every day, twice a day.
The technology for testing these samples for the different isotopes and exact measurements that are actually useful was invented and brought to the island in 1978.
Let that sink on. They collected jars of air for 20 years before they actually had a way to test them properly, and did it every day, twice a day.
All good scientists are mad scientists, the crazier, the better.
Hyzenthlay87:
The mental image is sort of adorable 🤣
The technology for testing these samples for the different isotopes and exact measurements that are actually useful was invented and brought to the island in 1978.
Let that sink on. They collected jars of air for 20 years before they actually had a way to test them properly, and did it every day, twice a day.
All good scientists are mad scientists, the crazier, the better.
Hyzenthlay87:
The mental image is sort of adorable 🤣
57points
#2

After being a Behavioral Specialist for so long it is astounding how much of human behavior is built on wanting attention from others. Even me just writting this, the primary motivation would be to gain attention and demonstrate my knowledge. Sure I just want to share but even that is rooted attention seeking behavior. At first it’s a little disturbing realizing that non of us can escape it. But it’s part of being human. We are wired to be this social and it has helped us to survive.
Timely_Influence8392:
Cooperation is literally the single greatest survival tactic ever seen in nature. We were never meant to be as intentionally and artificially isolated and alienated from each other as we are today, and the modern obsession with individualist hostile competition, up to and including creating artificial scarcity through which to enforce this hostility, is antithetical to our very being as a species.
Timely_Influence8392:
Cooperation is literally the single greatest survival tactic ever seen in nature. We were never meant to be as intentionally and artificially isolated and alienated from each other as we are today, and the modern obsession with individualist hostile competition, up to and including creating artificial scarcity through which to enforce this hostility, is antithetical to our very being as a species.
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56points
#3

Fly around the surface of Earth once non-stop in a 747?
It would take around 2 days.
Fly around the Sun once non-stop in a 747?
Around 6 months.
Fly once around the largest star discovered in a 747?
1,200 years.
Fly across the Milky Way once in a 747?
120 billion years.
jframe42:
Fly around Brazil in a 747?
A Brazilian years.
It would take around 2 days.
Fly around the Sun once non-stop in a 747?
Around 6 months.
Fly once around the largest star discovered in a 747?
1,200 years.
Fly across the Milky Way once in a 747?
120 billion years.
jframe42:
Fly around Brazil in a 747?
A Brazilian years.
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55points
#4

Your stomach lining regenerates every few days. Otherwise stomach acid would literally digest your own organs. You're constantly saving yourself from yourself.
f4ttyKathy:
This is why chemo is so hard on your digestion and leads to nausea. Chemo targets fast-growing cells and isn't very precise, so it's constantly messing up the cell turnover in your stomach.
f4ttyKathy:
This is why chemo is so hard on your digestion and leads to nausea. Chemo targets fast-growing cells and isn't very precise, so it's constantly messing up the cell turnover in your stomach.
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49points
#5

Oncology scientist. Pharmaceutical companies are not hiding the cure to cancer. Whoever finds the cure to cancer will be bring too much value to the shareholders for it to be squashed.
nefanee:
As a former cancer patient, when people would say this stupid stuff to me I would tell them if my oncologist had a cure, there was nothing that could stop him from getting it out. Then I would cut that person out of my orbit.
You are doing the real work and I thank you for it.
nefanee:
As a former cancer patient, when people would say this stupid stuff to me I would tell them if my oncologist had a cure, there was nothing that could stop him from getting it out. Then I would cut that person out of my orbit.
You are doing the real work and I thank you for it.
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47points
#6

About 99.86% of all the mass in the solar system is inside the sun.
Everything else combined--all the planets, moons, asteroids, comets, kuiper belt objects, oort cloud objects--is a rounding error compared to the sun.
The Earth has about 0.0003% of the solar system's mass. We are decimal dust.
ModernSimian:
Except your Mom, she alone accounts for at least .00005%.
Everything else combined--all the planets, moons, asteroids, comets, kuiper belt objects, oort cloud objects--is a rounding error compared to the sun.
The Earth has about 0.0003% of the solar system's mass. We are decimal dust.
ModernSimian:
Except your Mom, she alone accounts for at least .00005%.
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46points
#7

Mushrooms are closer to animals than to plants. In fact, in our current phylogenetic classification, fungi are even closer to animals than to slime moulds.
MinkusRotciv:
Mushrooms digest their food outside of their bodies.
jargon_ninja69:
It's why treating fungal infections in humans is SO DIFFICULT because both fungal cells and human cells are eukaryotic (meaning they have membrane bound nuclei) and anti-fungal meds truly can't tell the difference, so they end up destroying both.
MinkusRotciv:
Mushrooms digest their food outside of their bodies.
jargon_ninja69:
It's why treating fungal infections in humans is SO DIFFICULT because both fungal cells and human cells are eukaryotic (meaning they have membrane bound nuclei) and anti-fungal meds truly can't tell the difference, so they end up destroying both.
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38points
#8

The amount that your body's microbiome affects you. Studies have shown that reduced cravings for alcohol were achieved after fecal transplants. Also we are about 1:1 Human cell and microbe.
niqueyq:
I remember when fecal transplants were new and I was being considered for one, they also said early studies has shown several obese people who had the transplant then lost weight as the food noise stopped. So makes sense about alcohol.
niqueyq:
I remember when fecal transplants were new and I was being considered for one, they also said early studies has shown several obese people who had the transplant then lost weight as the food noise stopped. So makes sense about alcohol.
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38points
#9

Farmer here. Seems obvious, but just how many resources nature has to throw at EVERY problem (in this context, "problem" means your healthy crop).
Our solutions for pest / disease issues on crops are incredibly specific. Develop a specific insecticide that targets the digestion of a gnat, or the reproductive cycle of a worm. Nature has 24/7 to develop infinite new evolutions of that pest / disease that will circumvent your incredibly specific mode of action.
Follow up - no...nature WONT "just provide for us". Nature will provide for itself. All the crops we eat have been developed by humans to feed us. If you ever doubt that, look up the native species we derived corn or apples or strawberries from. They look nothing like the crops we enjoy today.
Our solutions for pest / disease issues on crops are incredibly specific. Develop a specific insecticide that targets the digestion of a gnat, or the reproductive cycle of a worm. Nature has 24/7 to develop infinite new evolutions of that pest / disease that will circumvent your incredibly specific mode of action.
Follow up - no...nature WONT "just provide for us". Nature will provide for itself. All the crops we eat have been developed by humans to feed us. If you ever doubt that, look up the native species we derived corn or apples or strawberries from. They look nothing like the crops we enjoy today.
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38points
#10

"The fact that atoms are 99.9999999% empty space. If you removed all the 'empty space' from the atoms that make up every single human being on Earth, the entire human race—all 8 billion of us—would fit inside the volume of a single sugar cube. We feel solid because of electromagnetic fields pushing against each other, but in reality, we are essentially just 'organized nothingness.' You aren't actually 'touching' the chair you're sitting on right now; your electrons are just repelling its electrons so strongly that it creates the illusion of a solid surface.".
edStixon:
I might be wrong, I could swear I read a paper one time that explained that because there is so much empty space, it's theoretically possible that in the perfect conditions, you could accidentally "phase through" a solid object instead of bumping into it if everything was aligned just right on an atomic level. (But the odds of it are so astronomically insane, it's basically guaranteed it'll never actually happen in human history.)
edStixon:
I might be wrong, I could swear I read a paper one time that explained that because there is so much empty space, it's theoretically possible that in the perfect conditions, you could accidentally "phase through" a solid object instead of bumping into it if everything was aligned just right on an atomic level. (But the odds of it are so astronomically insane, it's basically guaranteed it'll never actually happen in human history.)
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37points
#11

Every breath you take today likely includes at least one molecule once exhaled by Julius Caesar when he passed away.
How?
Because the atmosphere thoroughly mixes over time, and each breath contains an enormous number of molecules — ~1 × 10²² molecules.
But it can get even more interesting. Due to the number of molecules in our atmosphere and those in each breath, and given enough time, every breath you take likely includes a molecule of air once breathed by…
Taylor Swift at that concert a few years ago
W. Shakespeare
Medieval peasants
Cleopatra
Jesus of Nazareth
Woolly Mammoths
And even Dinosaurs
Want to blow your mind even more?
Every time you drink a glass of water, at least one molecule of that H₂O likely passed right through a dinosaur.
How?
Because the atmosphere thoroughly mixes over time, and each breath contains an enormous number of molecules — ~1 × 10²² molecules.
But it can get even more interesting. Due to the number of molecules in our atmosphere and those in each breath, and given enough time, every breath you take likely includes a molecule of air once breathed by…
Taylor Swift at that concert a few years ago
W. Shakespeare
Medieval peasants
Cleopatra
Jesus of Nazareth
Woolly Mammoths
And even Dinosaurs
Want to blow your mind even more?
Every time you drink a glass of water, at least one molecule of that H₂O likely passed right through a dinosaur.
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33points
#12

The atoms in your body are older than the Earth.
Most of them were formed inside exploding stars billions of years ago.
You’re literally recycled stardust walking around arguing about WiFi speed.
kranools:
Is this why I feel so tired?
fork_spoon_fork:
And part of the white noise (static) on an analog TV is the Cosmic Microwave Background (CMB), which is the cooled-down remnant radiation from the Big Bang! pretty rad eh.
Most of them were formed inside exploding stars billions of years ago.
You’re literally recycled stardust walking around arguing about WiFi speed.
kranools:
Is this why I feel so tired?
fork_spoon_fork:
And part of the white noise (static) on an analog TV is the Cosmic Microwave Background (CMB), which is the cooled-down remnant radiation from the Big Bang! pretty rad eh.
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32points
#13

Your brain can’t feel pain. Surgeons can operate on it while a patient is awake.
jessek:
There's some surgeries that require the patient to be awake and giving feedback to the surgeons as they poke around in there too. It's completely freaky to watch.
dragoon7201:
That is true but not unique to the brain. The actual brain tissue and most of your solid organs don't have nerve endings and can't feel pain.
But the sac around the brain (meninges) do have nerve endings and can cause quiet the headache as they are packed with pain receptors, similar to the sac (viscera) around other solid organs.
The other important part of putting you under is actually to paralyze your muscles so they don't spasm around during the procedure.
So a lot of surgeries can technically be done with you awake and feel no pain. But this is more common in neurosurgeries as for many procedures they need to monitor your brain function to avoid accidentally damaging the wrong part.
A lot of joint surgeries are actually done with you awake if they don't need to cut through any muscle.
jessek:
There's some surgeries that require the patient to be awake and giving feedback to the surgeons as they poke around in there too. It's completely freaky to watch.
dragoon7201:
That is true but not unique to the brain. The actual brain tissue and most of your solid organs don't have nerve endings and can't feel pain.
But the sac around the brain (meninges) do have nerve endings and can cause quiet the headache as they are packed with pain receptors, similar to the sac (viscera) around other solid organs.
The other important part of putting you under is actually to paralyze your muscles so they don't spasm around during the procedure.
So a lot of surgeries can technically be done with you awake and feel no pain. But this is more common in neurosurgeries as for many procedures they need to monitor your brain function to avoid accidentally damaging the wrong part.
A lot of joint surgeries are actually done with you awake if they don't need to cut through any muscle.
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31points
#14

I learned that the metric our brain use to tell our body to breathe is not how much oxygen is coming in, but by the amount of carbon dioxide in our body. So if we enter an area that has no oxygen and very low carbon dioxide our body wouldn't know we'll just pass out and pass away.
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29points
#15

Some algae species (phytoplankton) are microscopic and they are capable of producing oxygen. Making them more efficient than trees at that role.
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29points
#16

PET scans sound straight out of scifi.
We inject a specific radioactive tracer into your body. The isotope emits positrons (literal antimatter) as it decays. The positrons interact with electrons in your body and annihilate creating gamma ray bursts and we are able to track that light/energy to create a detailed 3D map of your body.
We use antimatter everyday to help save lives.
Subtotal9_guy:
All the kinds of nuclear imaging are crazy. We routinely inject radioactive materials into healthy people to study and diagnose disease. PET scans are just one of the more advanced systems for it.
Apparently you need a special certificate to inject radioactive material, a different certificate to inject blood and a third certificate to inject radioactive blood.
We inject a specific radioactive tracer into your body. The isotope emits positrons (literal antimatter) as it decays. The positrons interact with electrons in your body and annihilate creating gamma ray bursts and we are able to track that light/energy to create a detailed 3D map of your body.
We use antimatter everyday to help save lives.
Subtotal9_guy:
All the kinds of nuclear imaging are crazy. We routinely inject radioactive materials into healthy people to study and diagnose disease. PET scans are just one of the more advanced systems for it.
Apparently you need a special certificate to inject radioactive material, a different certificate to inject blood and a third certificate to inject radioactive blood.
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26points
#17

The double slit experiment. Light can behave like either particles or waves, depending on whether it is "observed" or not. When not observed light will show an interference pattern or act like a wave. But when observed it reverts to particle behaviour. Creepy science.
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26points
#18

For decades we have known that 2 tricks to help you lucid dream are looking at your hands or trying to read text because dreams don't do hands or text well and can be clue that you are in a dream.
Why the hell are dreams and AI suffering from the same glitch?!?
Personal-Bonus-9245:
Literally had this happen the other night while dreaming. Had a frustrating dream that required me to use my phone, and whatever I texted on it, giberrish came out. That’s when I realized I was dreaming. Woke up almost immediately.
Why the hell are dreams and AI suffering from the same glitch?!?
Personal-Bonus-9245:
Literally had this happen the other night while dreaming. Had a frustrating dream that required me to use my phone, and whatever I texted on it, giberrish came out. That’s when I realized I was dreaming. Woke up almost immediately.
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24points
#19

I’m personally a big fan of relative size of things. If you were to stretch out all of the DNA in a single cell, it would measure 2 meters or 6.5 ft! On a more macro scale, the surface area of human lungs is equivalent to a tennis court.
I have a PhD in molecular biology and worked as a professional protein biologist for a bit. I miss it, but my health was declining and my brain and hands just aren’t built for fast-paced science anymore (shoutout to MS!)
MollyPollyWollyB:
Fractal infinities within the human body absolutely blow my mind. Like I get it, but also how is it possible to have enough space within my lungs for them to infinitely branch off into smaller and smaller alveoli? Or for my brain to contain an infinite amount of neuronal networks? Each of us is the size of a universe when size is relative to infinity. We are all infinitely large and infinitely small just as we are every moment of our lives every moment we are alive, as far as we think we know anyway (because meat suit limitations apply, probably).
I have a PhD in molecular biology and worked as a professional protein biologist for a bit. I miss it, but my health was declining and my brain and hands just aren’t built for fast-paced science anymore (shoutout to MS!)
MollyPollyWollyB:
Fractal infinities within the human body absolutely blow my mind. Like I get it, but also how is it possible to have enough space within my lungs for them to infinitely branch off into smaller and smaller alveoli? Or for my brain to contain an infinite amount of neuronal networks? Each of us is the size of a universe when size is relative to infinity. We are all infinitely large and infinitely small just as we are every moment of our lives every moment we are alive, as far as we think we know anyway (because meat suit limitations apply, probably).
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23points
#20

Spiders eat more biomass weight each year than the combined weight of all of the humans on earth, up to 800 million metric tons. Spiders eat more biomass than all of the whales in the oceans eat.
They are almost certainly the most important predator on earth.
They are almost certainly the most important predator on earth.
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23points


