We have come a long way in understanding how our bodies work. However, there are still mysteries
yet to be explained. Why do you yawn? What is the appendix actually for? Why do only
men find farts funny? We are going to talk about 20 things your body does that we don’t know why.
And as we go through our list, things are going to get stranger and stranger.
Starting with number 20 we are going to talk about boobs. There are a few attributes for
male and female breasts that we don’t quite understand. For example, all mammals have some
form of breasts. This is because mammals tend to take care of their young after they’re born.
Breasts are an effective delivery device for feeding a young infant. However,
only human females have enlarged breasts even when they are not rearing offspring.
This is extremely strange, because in the evolutionary scheme of things having constantly
large breasts can be an inconvenience, get in the way, or may even send the wrong signals.
Most people think that the permanently large breasts of human females actually attract men.
However, in many cultures men do not find large breasts attractive,
so this seems unlikely. Another theory is that the constantly large breasts of human females may have
to do with the large brains of human offspring. It is thought that the hormones created in the
breasts promote fat storage that gets released into the milk when the mother breastfeeds,
making the milk extra nutritious. This has not been proven yet, so as of right now,
we have no idea why human females have enlarged breasts throughout their life.
And speaking of boobs, number 19 has to do with the male breasts.
We don’t fully understand why males have nipples at all.
Think about it. Nipples are used as a way for babies to suckle milk from the mother’s breasts.
Since males can’t produce milk, there is no reason for them to have nipples. All the
male nipple really does is confuse the baby if they start sucking on it and nothing comes out.
Hopefully, you’re still excited to learn more about what we don’t know about our own bodies.
But if at this point you’re yawning, then you’re already ahead of the game.
Number 18 on our list is: Why do we yawn? We don’t know!
We do know that yawning tends to occur when we’re tired or bored. We might start to yawn
when we see others doing it. In fact, I bet since you’ve heard the word yawn
a few times already, you might even be doing this mysterious act right now.
And if not, I bet you’re definitely holding in a yawn. But what is the purpose of yawning?
Originally scientists thought yawning was a way to get more oxygen to the brain,
and therefore, make the body less tired. But this does not seem to be the case. More recent research
might suggest that yawning is a way to cool off the brain. The yawn circulates cooler blood
up to the brain to help lower the temperature in the skull. This is still being researched,
and many scientists disagree with this idea, but at least it is one explanation for why we yawn.
Other scientists suggest yawning is a form of communication. This is why when one person yawns,
people around them start to as well. Long ago in human’s ancient past,
yawning may have been a way to signal to the group it was time to rest.
If everyone was yawning and felt tired, then it was time to stop. There is always
safety in numbers, and contagious yawns may have been a way to keep the group together.
Number 17 is another form of contagious behavior that we don’t quite understand, laughing. We
laugh when something is funny, or maybe if we are extremely uncomfortable, but why do we do this?
Laughing may have the same root cause as yawning, in the sense that it is a way to
make sure a group of people are on the same page. It has been hypothesized that the reason we laugh,
and that laughter is contagious, is because humans are social creatures. We want to fit
in with the group, and laughter may be a form of empathy to connect with others in a social
setting. When we laugh the brain releases endorphins, which makes us feel at ease.
So, we don’t know exactly why we laugh, but it makes us feel good, especially in social groups.
However, this does not explain why we sometimes laugh when we are all alone.
Or why you might get the giggles when you think of a past funny experience.
Maybe laughing is just a way for your body to boost morale and make itself feel better.
Number 16 is an action your body does that is connected to your emotions.
You may be a little embarrassed when we tell you about this one.
When you blush your face turns red. We know how it turns red, but we have no idea why it happens.
The reddening of the face that is connected to blushing happens when the capillaries
near the surface of the skin expand and let more blood rush through the area. However,
this does not explain why our body makes this happen. One reason might be to serve
as an identifying factor for liars. If someone in your social group is lying they might blush,
and if they get caught, this could cause them to blush even more.
It has been suggested that the most likely reason blushing occurs is as a social cue.
Interestingly, research has shown that blushing is a positive behavior in social interactions.
Maybe this is because people who blush may be considered more trustworthy
since they have such an obvious tell if they are lying. Charles Darwin even called
blushing "the most peculiar and most human of all expressions," because even though
we can explain how blushing occurs, we really have no idea why our bodies do it.
This brings us to something the body does that seems so simple,
yet is shrouded in mystery. Number 15 on our list is: why do we sleep?
At a basic level we might just assume our body needs sleep, so we can rest.
But our body can rest without falling asleep, so why do we sleep at all?
Almost every animal sleeps in some form, whether it is short naps or long stretches at night,
this process seems important to all animals. But why is it necessary? When you think about it,
falling asleep is really dangerous if you live somewhere there are predators trying to hunt and
eat you. When you sleep you are unaware and vulnerable, so it would stand to reason that
natural selection would eventually get rid of this dangerous process, but that hasn’t been the case.
Most scientists think sleep is a way to recharge the brain and allow the body
to build up stores of energy. It may also be a way for us to transfer information and memories
into different parts of the brain. It has even been suggested that sleep is necessary
to bring brain cells back to a baseline state, so that the brain doesn’t overload.
However, the fact remains that we are not entirely sure why we sleep.
And for number 14 we are going to take things one step further, why do you dream?
If sleep may be used to reset your brain cells,
why does your brain then create vivid stories for you to experience while you sleep?
Again we don’t actually know why our bodies do this. It has been proposed that dreams are the
way your brain regulates mood, or catalogues the events of the day. On the other hand,
some scientists suggest that dreams are just an accidental side-effect of your neurons firing.
We spend up to a third of our lives sleeping and dreaming, yet we do not actually know why.
For number 13 we are going to talk about how weak you are. You may be offended,
but it’s not just you, it’s all humans.
The human body is surprisingly weak when compared to our closest relatives. If you put a chimpanzee
and human next to each other, you would see more similarities than differences. We share over 98%
of our DNA with chimps, so on a biological level, we are absolutely more similar than different.
But when we look at the strength of a chimp versus that of a human, we are so much weaker.
Our bodies have most of the same muscles, but chimps' bodies are three times stronger than
ours. And the crazy thing is, we just don’t know why we are such weaklings.
It may have to do with the way our muscles attach to each other. In the wild, an 85 pound
chimp was seen easily snapping the branches from an ironwood tree with her fingertips.
However, when a human tried to do the same thing using both of their hands,
they couldn’t break that very same type of branch. It is still a mystery why
our bodies are so embarrassingly weak when compared to our closest relatives.
And talking about hands, number 12 has to do with
our body having a peculiar trait in these appendages.
It is unclear why humans have a dominant hand at all. The vast majority of humans are right handed,
but why? And what does that say about left handed people? Many scientists think it has
something to do with the speech center of the brain. This is found in the left hemisphere,
which controls the right side of the body. There might be a connection between speech and having a
dominant hand, but other research shows that not all right handed people control their speech from
the left hemisphere. So what it comes down to is, we have no idea why our body has a dominant hand.
There is also no explanation for number 11 on our list: why do we have fingerprints?
Yes they are unique, and yes they can be used to identify someone, but what function do they
serve? For a long time we thought that our fingerprints helped us grip things,
but this has been shown not to be the case. It has been suggested that maybe the fingerprints allow
us to have more sensitivity when touching things, but this has not been proven yet. As of right now,
we will just have to accept that our hands are still somewhat of a mystery to us.
As we get into the top 10 things we don’t understand about your body things are going
to get pretty out there. You are definitely special. And besides fingerprints there are
other differences between you and every other human on the planet.
For example, why do humans have so many different eye colors? We know that the color of your eyes
is determined by your genes and the pigments that are created by the cells in the eyes,
but why do we need blues, greens, browns, or a combination of these colors? Maybe it’s
just to make our eyes pretty, but really we don’t know why eye color is so varied.
This goes for number 9 on our list as well. Why do we have different blood types?
It would be much more convenient for doctors and medical professionals if we all had the
same blood type, but this is not the case. It is true that some blood types are more resistant
to certain infections than others. Therefore, one type of blood may have been beneficial in
a certain part of the world, and a different type of blood may have been better adapted to another.
Since humans evolved in Africa and spread across the globe, different blood types may have been a
byproduct of the process of natural selection for different environments. But we aren’t 100% sure.
Continuing on with your special characteristics numbers 8
and 7 have to do with the hair, or lack thereof, on your body.
Hair color varies greatly, but there is something else about hair that we don’t quite understand.
Why do we need it on our bodies at all? Hair on the head and face definitely serve a purpose,
but what about body hair? We do not grow enough body hair to make a significant difference in
temperature regulation. At one point in our distant past humans had much more body hair,
which would keep us warm or help in cooling us off;
but today it is hard to find someone with enough body hair to make that much of a difference.
If you lost all of your hair tomorrow, you wouldn’t miss it. Well, at least not in
terms of any biological reasons, so we don’t exactly know why we still grow body hair.
This brings us inside of your body for number 6 on the list.
You have trillions of little creatures living inside of you right now.
In fact the microbes in your body out number your own cells about 10 to 1. That’s crazy!
We know that some of the bacteria in your body helps you with digestion and other life functions,
but this is just a small percentage of the whole. So why does your body
allow trillions of microbes to live within it? We don’t know. The study of the human
microbiome is a relatively new field, and we are still learning. But for right now,
you are home to an entire ecosystem of microbes and we have no idea why most of them are there.
And now we hope you’re ready for number 5,
which is a little gross when you think about it, so hopefully you didn’t just eat a big meal.
We don’t actually know how all those microbes got inside of you in the first place.
You were definitely born with some, and you pick up others through food, water,
and even the air you breathe. But everyone’s microbiome is different,
so how does your body gather its unique grouping of microbes? No one really knows. However, when
you sleep with someone you are probably swapping more than just pleasure and bodily fluids,
you are also exchanging microbes. Think about that next time you hookup with someone.
You’ve probably heard of number 4 on our list. It is commonly thought that your appendix serves no
purpose. You may even be one of the 1 in 15 people who have had their appendix removed,
so why does your body even have the organ? Some scientists think
it's just a vestigial structure left over from our evolutionary ancestors.
Others believe that it still serves a function in the development of the fetus, or is useful
for producing certain proteins and hormones that could be beneficial to our bodies. But the fact
that you can live without it begs the question: why is it even there? We honestly don’t know why.
This brings us to the end of our list. Our last
three unexplained phenomena in your body come from the same place: the brain.
To start us off; we have no idea how the brain actually works. We know that there
are trillions of neural connections that work together to keep you alive and allow
you to watch the insanely interesting videos put out by The Infographics Show,
but really, we don’t know how the brain actually functions as a whole.
The brain is made up of atoms and molecules just like everything else in the universe,
yet it is the only thing we know of that can control a body, think, and even dream.
Number 2 on our list is that we don’t know how your brain allows you to react and move with ease.
No one can explain how your brain is able to move billions of cells in an instant. Also,
how do the chemical reactions that keep you alive and moving on a day to day basis even occur?
Doing something as simple as typing a few words on a computer requires massive amounts
of signals going from your brain to your fingers. You also need your eyes to see and
send information about where the buttons are. All of that information is fed to the brain,
which must then interpret it and send out new signals in a split second. We have no idea how
your brain can make your body do exactly what you want in only tenths of a second.
Finally we are at the end of our list of things your body does that we just don’t understand,
and we are about to get pretty metaphysical.
What makes you you? Well your DNA is responsible for your traits, but your consciousness is
responsible for who you are and your personality. How does your body create consciousness? We have
absolutely no idea. It probably comes from the brain, but we aren’t even 100% sure of that.
You could go down a deep, dark, rabbit hole trying to figure out what consciousness is,
where it comes from, and why your body creates it. Or you could just chalk it
up to being something else your body does that we don’t yet understand.
Now watch “What Happens to Your Body After You Die?”
Or check out “Crazy Things A Doctor Removed From Inside Person's Body.”