40 Cool But Pretty Disturbing Facts About The Human Body That Not Many People Know About
The human body is a crazy thing. After evolving for about 6 million years, our bodies that include 206 bones, a couple gallons of blood, around 600 muscles and much more, are capable of incredible things. We might not all be climbing Mount Everest or competing in the Olympic Games, but every single one of us has a body that is working incredibly hard to keep us alive. And while we spend our entire lives in these fascinating skin suits, many of us don’t actually have a great understanding of how they work.
That’s why one Reddit user, Alwaysclimbing5, reached out asking others to share cool facts about the human body that a lot of people don’t know. Readers chimed in with fascinating information, including anything from how we can be born with extra ribs to how sensitive our noses are to the scent of rain, so we’ve gathered the most interesting responses down below for you to read, as well as an interview with Dr. Scott Ross about some of the craziest things he knows about the human body. We hope you'll enjoy your daily dose of biology and that you learn something new about yourself while you're here. Don’t forget to upvote the facts that really blow your mind, and then if you’re interested in finding out even more about our bodies, check out this Bored Panda piece next.
Lactose intolerance is a normal gene. Being able to drink milk is a mutation.
How much do you know about the human body? Chances are, unless you work in the medical field, many of our bodily functions are a mystery to you. No matter how well you paid attention in freshman year biology, there is a reason why it can take over a decade to become a doctor. Our bodies are incredibly complex. Adults have more than 46 miles of nerves and over 60,000 miles of blood vessels inside of us, while our brains have about 100 billion nerve cells. Not to mention how intelligent we are and how we function based on free will and make choices in accordance with society, rather than simply following impulses without any thought process.
But as previously mentioned, our current forms took millions of years to evolve. Perfection does not happen overnight, right? Most scientists agree that there were about 15-20 different species of “early humans” before us, with Homo sapiens becoming, for the most part, how we are today about 300,000 years ago. It makes sense that during all of that time our bodies became increasingly complex, particularly our brains, but it certainly makes it hard for scientists and doctors to master their understanding of the human body today.
We reached out to Dr. Scott Ross to hear what the craziest fact he knows about the human body is. "If a person donates half his liver to a person in need, the donor's liver can regenerate to its full size in about 6 months," he told us. That's definitely something I did not know, but I'm glad I know now! We also asked Dr. Ross what makes the human body so special. "The complexity of the human body from the fertilization of the egg by the sperm to development and then the interaction of all the organ systems is truly a miracle," he told Bored Panda. "Whether it be the chemistry of food digestion, the physics of joint motion or the functioning of the human brain, every aspect of the human body is truly amazing."
Lastly, we wanted to know how much of the human body is still considered a mystery. "It is impossible to know what we don't know about the human body but suffice it to say, we continue to learn new things about the body as research and technology advances." I cannot even comprehend everything that doctors and scientists already know, so it is mind-blowing to think that their education never ends. Thankfully, it's not my job to know, so I can always go to experts like Dr. Ross to find out what's causing that strange tingling in my elbow.
If we were an RPG character, our main stat would be endurance.
We are, by animal standards, hellishly undying and unrelenting terrors, these Terminator-esque nightmares that just DO. NOT. STOP.
So ancestrally we are persistence hunters. That is, our main tactic for catching prey without fancy weapons was to just run them down, especially in our way-back home of the African desert. You can still see it, all over the human body.
We are nearly hairless. This lack of insulation means better heat dissipation. We have a *ton* of sweat glands, next to other mammals. Again, heat dissipation. Another one is our two-legged gait - walking for us is technically just a series of controlled falls. We let gravity do half the work, and as a result use up fewer resources and generate less heat (quadrupeds, on the other hand, have to do more work with more legs).
I mean, imagine being a more-or-less gazelle of half a million years ago. You're eating, doing your thing, when this predator arrives, so you run off. Now most predators, they'll only chase for a short distance and then call it a day (watch cats, for instance). But this one... here he is again. So you run. He returns. You run again. He returns. You're getting hot - you have to stop and pant to lose heat, but he just keeps jogging. You run. He keeps coming. You're tired - you're fast, but not for very long, and this stretches your limits.
Eventually you just lay there, exhausted and heat-stunned, and this ludicrous hairless monkey just jogs on over and kills you.
That's our claws, our sharp teeth, even without our technology and tool-making. We simply don't stop.
There are many aspects of being a human that makes us unique to other creatures, so we consulted Live Science to see what they think the top 10 traits that make humans special are. First, they mention our speech as a unique characteristic of humans. They explain that essentially, the size of our brains makes it possible for us to have a wide vocal range and precise control over our vocalizations. “In simple terms, primates with bigger cortical association areas tended to make more sounds," says Jacob Dunn, an associate professor of evolutionary biology at Anglia Ruskin University. This special feature has allowed our species to develop over 7,000 different languages.
The fact that we walk on two legs is also unique compared to many species. Having our hands free while walking makes us capable of doing multiple things at once, like using tools (or let's be honest, texting and walking). However, Live Science notes that there are downsides to this trait as well. The way our bodies evolved to walk upright has made human birth particularly dangerous compared to many other animals. Our pelvises are not made for pushing out babies with large brains, and the lumbar curve in our spines makes us prone to developing back pain.
When you are exhausted and go to bed your body shuts down faster than usual. That 'jerk' or 'kick' that your leg makes is a signal from the brain to make sure you are not dying. Your body takes a a while to slow down to sleep but whilst exhausted your brain double checks to make sure you are still alive by sending a message from your brain to to the bottom of your body to check if your nerve sytem is still functional. This is usually a quick kick of your predominant leg.
Natural redheads require increased doses of anesthesia, due to some connection with the mutated melanocortin-1 receptor. I’m a natural redhead myself, and developed a fear of dentists because I’d always feel what they were doing!
Eventually I had an issue that couldn’t be ignored, and had to find a new dentist. At my first visit he took one look at me, and said “You’re a real redhead, huh?” “Yup.” “(Hygienist), get me 4x the novocaine!” I knew I’d found my man, and he’s been treating me ever since... also shed my fears, since dental work is much less unpleasant when you’re actually numb before they start.
Breastmilk will produce antibodies to help baby fight off disease. It’s thought that’s babies saliva enters the nipple, mums body tests for any undesirable bacteria, then produces milk to help fight it off.
For this reason, it’s not unusual for breastmilk to look different when baby is sick. Sometimes very dark yellow and thick, almost like colostrum. It also contains different hormones depending on the time of day, and is antibacterial. It is a living liquid
Compared to most other mammals, humans are also relatively hairless. I know what you might be thinking, your husband has the hairiest back you have ever seen or you believe that your legs are covered in fur. But if you compare yourself to a bear or a chimpanzee, you might be feeling smooth as silk. We used to have much more body hair, but apparently, about 2 million years ago, an adaptation caused our body hair to “miniaturize”, while another adaptation caused us to have many more sweat glands than most other mammals. Today, these adaptations make it much easier for us to cool off. So as much as you might despise returning home from a run dripping wet, know that we are lucky to have developed all of these sweat glands.
Really late but I discovered this thing during my thesis.
We were researching patients with neurological problems and people who had brain injuries and we found a woman in her 30 that had had part of her brain removed. More specifically the area that activates when you move your body.
Well she was moving and talking with just some minor missteps and theoretically it was not possible, she was paralyzed in the first 3 months after the operation (she was caught in a car accident if I remember correctly).
We were trying out a new scanner for the brain and we found out that an area of the brain that wasn't supposed to work and control the movement was doing just that. The occipital area (usually controls the vision) was now working as a motor control area.
The brain is really amazing...
When were in an unfamiliar environment we sleep with half our brain at a time kinda like sharks and that's why we wake up easier.
I work in an ER and a guy came in because he had non-stop hiccups for six days. Every 45 seconds or so he would hiccup. He was going insane because he couldn’t sleep or focus and had a hard time eating.
After running tons of tests and almost giving up hope on helping this guy, one of the nurses looked in his ears and found q-tip cotton stuck inside and as soon as the cotton was removed, the hiccups stopped completely.
Dude was so relieved he cried.
Due to our mostly “naked” bodies that are not fully covered in hair or fur, we have developed a need for clothing to keep us warm and protected from the elements. And while this is not a solely human trait, as chimpanzees have been documented wearing “necklaces” and “earrings”, those were purely for aesthetic reasons. We often need clothing to shield us from cold weather or rain and to protect our feet from being damaged on the ground. Humans are also required to wear clothing to be part of most societies. Animals don’t stigmatize the naked body, but for some reason, most humans do. Whether you agree with the requirement to wear clothing or you would rather live in a nudist colony, it is certainly one more way that humans stand out from the pack.
When we get sunburn, that's not the heat of the sun that's hurting us most of the time, but it's little skin cells killing themselves to protect us from skin cancer.
Not so cool if I think about it.
You can give birth after you've died.
Occasionally we will come across a really confronting burial where the skeleton of an unborn child is halfway through its mothers pelvis. Generally what happens is the woman has died before giving birth and after burial a build up of gasses from decomposition forces the baby out. We refer to this as "coffin birth".
Eye immune privilege: Your immune system doesn't know your eyes exist. Theres a chance that if you get an eye injury or an infection near your eyes the immune system will think your eyes are a foreign body and you'll go blind.
One of the most special things about the human body is our famously overdeveloped cerebral cortex. It makes up over 80% of our brain’s mass and allows us to use complex, higher level thinking skills, such as making decisions, executive control, emotional regulation and using speech. Our amazing brains are responsible for only 2% of our total body weight, but they use up more than a quarter of our body’s energy. And although we don’t have the largest brains in the world, that would be sperm whales with brains weighing up to 20 pounds or 9 kilograms, we do have the most impressive brains. With our complex reasoning abilities and intricate societies, we are definitely among the most intelligent species.
The bone that supports your eyeball, called the orbital floor, is paper thin and has a large empty cavity, called the maxillary sinus, on the opposite side. When you get hit hard in the eyeball, instead of your eyeball itself rupturing, the bone underneath your eye breaks, which is called an orbital floor fracture. This releases the pressure from the impact and saves your eyeball. If you crush a beachball against a concrete wall, you can pop it, but if you try crush it against a styrofoam wall, the wall breaks but the beachball is fine. An amazing evolutionary adaptation to protect your eyesight.
You mostly breathe out of one nostril at a time, and the ‘dominant’ nostril switches every hour or so.
You just need to focus on the time you want to wake up and our hypothalamus would wake us up at the exact same time.
Another feature of the human body you might want to give yourself a hand for developing is, well, your hands. We may not be the only species that has opposable thumbs, as most primates do, but our thumbs are particularly large. It is unique that we can bring our thumbs all the way across the palm of our hands, which makes it much easier for us to pick up objects than most other primates. We also have impressive muscle control in our hands, allowing us to write precisely, play sports with accuracy, provide excellent massages and create amazing visual art. We are actually pretty lucky to have such versatile hands. I'd like to see a monkey type this paragraph or play the piano!
Women are actually programmed to forget the pain of child birth after a few months or so. If this didn’t happen, most women would only end up having one child, which would eventually lower the population.
You can see your nose all the time, your brain just chooses to ignore it.
We have an internal regulator that prevents us from using our full strengh. Or muscles usually only work at about 60% max of what we are capable off.
In extreme life and death situations these regulators stop and we are able to use our full strengh. This is how the parts where people tipped over cars and similar come from.
These regulators are because at full strengh we heavily damage our bodies. Essentially, you could lift something to the point where it is either lifted or your arm just breaks instead. I believe there has also been someone who ran so hard his leg broke.
The ability to blush is also a uniquely human characteristic. Darwin referred to blushing as “the most peculiar and the most human of all expressions”, but perhaps he never had someone tell his crush that he liked them in middle school. Nothing peculiar about the reaction of blushing then; it felt like a perfectly appropriate response in my opinion… But there is a theory that blushing was developed as an evolutionary response to acknowledge a mistake or embarrassment without having to address it verbally. “A prerequisite for embarrassment is to be able to feel how others feel — you have to be empathetic, intelligent to the social situation," says Ray Crozier, an honorary professor at Cardiff University’s School of Social Sciences. If the person you’re talking to can see that you are clearly aware of your mistake, there is no need to bring it up. I only wish everyone was polite enough to take blushing as a silent signal, rather than commenting, “Wow, you look really red!”
If you lose a hand and then have it reattached, even if all the feeling and movement ability comes back, your skin on that hand will never get wrinkly in water again. It's lost the ability to do so.
Also, the reason our hands get wrinkly after too long in water is to give us more grip on slippery surfaces.
Your liver can regenerate, and much faster than you think. I had a quarter of my liver removed, and a month later it was back.
A small percentage of people are "Super Sleepers" and are fully recharged after 2 to 4 hours of sleep each night. They get to burn the candle at both ends!
Something else that is fascinating about being a human is our long childhoods. While some other species have long lifespans like Asian elephants and blue-and-gold macaws, we are special in the way that it takes us so long to mature. Our childhoods are twice as long as chimpanzees, and even earlier versions of humans reached adulthood faster than we do today. There are several possible explanations for this, including the size of our brains and our long lifespans.
According to Associate Professor of Psychology Suzana Herculano-Houzel at Vanderbilt University, “It makes sense that the more neurons you have in the cortex, the longer it should take a species to reach that point where it's not only physiologically mature, but also mentally capable of being independent. The delay also gives those species with more cortical neurons more time to learn from experience, as they interact with the environment." I sometimes envy kids for their freedom and lack of responsibilities, so I am feeling really lucky right now that I'm a human. At least I got 17 years to enjoy being a kid, rather than a measly 3!
Your heart rate increases about a minute before partaking in exercise. It is known as the anticipatory rise and happens involuntarily.
The microscopic mites living on your face feeding off the oil glands.
You can't see them, but they're there. They are microscopic mites, eight-legged creatures rather like spiders. Almost every human being has them. They spend their entire lives on our faces, where they eat, mate and finally die.
There are two species of mite that live on your face: Demodex folliculorum and D. brevis.
It's cool cause that means I'll always have some friends with me.
Blind people process Braille in their visual cortex. Amazing example of neuroplasticity.
Humans, particularly females, are also very fortunate to have long lives after giving birth, without being expected to create more babies until they die. It is common for mammals to keep populating until they simply can’t go on, and even many species of octopuses die once they have mated and ensured their eggs would survive. But giving birth as a human is not supposed to be a death sentence. Of course, it can be in tragic cases, but most mothers get to live for many decades after having kids. Having kids is considered the beginning of many people’s lives, for individuals who view raising a family as their greatest dream. We are quite a lucky species because so many of us get to grow up with grandparents, sometimes even great-grandparents.
When you first set your sight on the seconds of a watch (or anything with a rapid regular movement) you will sometimes feel like the first second lasts a little bit too long. It's because your brain replaces the motion blur that happens when you moved your sight from wherever it was to the watch with a fixed image.
And the cool thing is that it replaces it "after the fact", or rather gives you a very short false memory that you were already watching the watch while your eyes were moving, making that first second seem longer.
It's called Chronostasis.
Some humans do not feel any pain and have to be closely monitored because they can get sick/injured so easily and not even realize.
When you're a baby you have several defence mechanisms that stop you from drowning: you reflexively hold your breath when underwater and your heart rate and consumption of oxygen decreases, allowing you to last significantly longer underwater than an adult.
While we tend to view ourselves as completely different from animals, the reality is that we just evolved in a different way. Our bodies are so special and incredible, and we are lucky to have complicated enough brains to have some level of understanding about how they work. We hope you're enjoying this list of fun facts about your body. Be sure to keep upvoting all of the facts that blow your mind, and let us know in the comments if you have any other little-known facts about humans that you would like to share. I'm sure it's been a long time since many of us have taken biology, and we would love to have a better understanding of ourselves.
A baby's body has about 300 bones at birth. These eventually fuse (grow together) to form the 206 bones that adults have
The human body contains enough fat to make seven bars of soap.
Your hands and feet alone account for more than half of all the bones in your body (106/206)
Cutting the corpus callosum ( connects two brain hemispheres) can produce some freaky results. Such as your hand doing s**t that your conscious mind isn't aware of, writing a sentence or scratching an itch without knowing for instance.
You're taller in the morning than the rest of the day/night.
There is a muscle, called palmaris longus, in the forearm missing in about 10% of the population. You can easy test if you have it by putting your pinky and thumb together, while holding your palm facing up, and flex the hand upwards. If 1 tendon is standing out more than the others that's palmaris longus.