From falling in your sleep to laughing out loud, here are 8 things your body does that
science cannot explain!
8.
Hypnic Jerk
Have you ever gone to bed after a long day and then start dropping off to sleep, when
suddenly-- you feel as though you're falling off a cliff and you jerk awake.
This is what is known as a Hypnic Jerk.
It’s an involuntary twitch which happens to a lot of people.
It doesn’t mean that waking up with your heart racing is pleasant!
They can be caused by stress, anxiety, too much caffeine, medication, or exercising late
at night.
It can also be your body’s way of sending us a message as a little "are you sure you
want to do this?" reminder before you enter the sleep state.
It is usually an indication that your body is really not completely relaxed or still
stressed, or when you didn't mean to fall asleep like when you’re driving.
It helps us to react to danger.
Another theory is that it has something to do with your brain not quite nailing the transition
between its sleeping and waking states.
When we're asleep, our brain temporarily paralyzes our body, this means that you don't get up
and act out even your most vivid dreams, but this paralysis can panic the waking brain,
which can become a night terror.
It is believed that if the brain gets the whole falling asleep and temporary paralysis
thing the wrong way round, it can trick it into thinking that something is terribly wrong,
causing it to jerk violently to be sure you haven't actually lost the use of your limbs.
It's also a great way of making your boss completely aware of the fact that you've just
dozed off in a meeting.
Again.
7.
Sun Sneezing
Sun sneezing, or the Photic Sneeze Reflex, is a phenomenon that causes some people to
have a sneezing fit when they look at a bright light.
Scientists call the effect an autosomal dominant compulsive helio-ophthalmic outburst (or ACHOO
for short, haha!!
Very witty!).
Whilst this sounds like something of an old wives tale, it is actually a real thing ... we
just don't quite know why.
One thing we do know, though, is that it's most likely genetic.
Sneezing is usually caused by irritation to the nasal cavity, so the fact that looking
at the sun should irritate your nose is a bit odd.
One possible explanation is that the eyes and the nose are closely linked via the fifth
cranial, nerve.
This means that when this nerve is activated by bright light, the signal also kinda tickles
the nose, tricking it into thinking there is something irritating it and causing the
sneeze.
While the effect seems pretty harmless, or even useful if you have one of those sneezes
that won't quite come, it can actually be pretty dangerous.
A photic sneeze can often be triggered by suddenly emerging from a tunnel while you’re
driving and it has even been recognised as a real problem for both commercial and military
pilots.
But even if we're not quite sure what causes it, we can still prevent the sun sneeze.
The best remedy?
A sweet pair of shades.
And now for number 6, but first if you are new here be sure to subscribe and click the
notification bell so you don’t miss out on the latest videos.
6.
Fingerprints
Without these guys, you could get away with murder, but no one is quite sure why humans
have fingerprints.
Most of the creases on your body are caused by repeated bending, stretching and wrinkling,
but the unique patterns on your fingers and toes are just there.
The prints form while we are still in the womb and, despite the popular belief, not
even identical twins have matching prints.
There are a couple of schools of thought about our fingerprints.
Some scientists think that they could be a way of improving grip in wet conditions, and
it is thought that this is also the reason behind why you go all pruney when you spend
all evening in the bathtub.
Another theory is that it increases the sensitivity of our fingertips.
We are able to detect lumps and bumps that are just 13 nanometres in size, so in this
case, it is highly effective.
It is thought that the common elliptical "loop" shape of the design is to ensure that some
ridges are always being dragged sideways over a surface, allowing them to sense its texture.
Either way, we're still pretty baffled as to what they're really for.
5.
Kissing
Kissing isn't something that you see throughout the animal kingdom, in fact, it isn't even
universal for all human cultures.
So this must mean that it's a culturally learnt behaviour and it is not something intuitive.
It has physiological effects on us, causing the body
to release the bonding hormone oxytocin, so it could have developed as a bonding practice.
There are many reasons thought to be behind why we kiss.
One of the most common is that our first experiences of comfort, security and love comes from when
our mothers mouth-fed us as infants, for example chewing food and passing it directly from
mouth to mouth.
This was done by our ancestors and is still sometimes practiced today in certain cultures.
However, cultures that practice kiss-feeding don’t always practice social kissing or
romantic kissing.
Another theory is that humans are naturally attracted to bright colours such as red to
help them spot ripe fruit, and this has somehow transferred over into sexual attraction.
This theory also goes on to explain that, because red lips are more prominent in Caucasians,
it suggests why it would have developed in northern latitudes and spread culturally from
there, explaining why it is not strictly a species-wide phenomenon.
There may also potentially be a link between kissing and assessing the biological compatibility
of our potential mates.
Some studies have shown that we are more attracted to the smell of sweat from people with immune
systems that are most compatible with ours, so it could well be that the same thing is
happening with kissing and saliva.
In any case, it is believed the Greeks learned about erotic kissing from the Indians when
Alexander the Great invaded India in 326 BC
4.
The Teenage Years
Teenagers are weird.
And I’m not just saying that as a boring adult, teenagers are genuinely, scientifically
weird.
You just don't get them in the animal kingdom.
You don't see bear cubs going around slamming doors, or baby turtles getting nose rings,
so what is it about humans that turns them from darling little angels into the spawn
of Satan for 7-9 years?
Why are humans so complicated??
It is thought that the reason why we all turn into greasy, bumbling dorks during our teenage
years is that our brain is essentially rewiring itself.
Scientists think that the reason the world suddenly doesn't make any sense the day after
your 13th birthday is because your brain is shutting down and rerouting neural pathways
in an attempt to build a brain that will be calm, and logical.
The puzzling thing is why this happens just as all of our hormones are going nuts.
urely once somebody becomes able to reproduce, it would make the most sense for them to be
a highly desirable specimen, and a solid evolutionary choice, rather than an insecure ball of nerves
who struggles to flirt.
Even science can’t explain that one.
3.
Sleeping
Sleeping is actually an odd thing, and not one that we understand all that well.
We need sleep or we would start to lose our minds and our brains would start to shut down.
People view sleep as a way for our brain and body to recharge its batteries in a sense.
The human body gets its energy from food.
The amount of energy "saved" by a good night's sleep is tiny, just about 50 kcal, and is
far outweighed by the amount of energy being used up as you sleep just to keep you alive.
So it's not really as though sleep is for "energy" in the usual way we would think.
It is thought that sleep is a way of maintaining proper brain function, allowing it to perform
maintenance without simultaneously having to deal with sensory input as it would when
you're awake.
It is also thought that this is what is behind dreaming.
Dreaming is also an odd phenomenon.
It allows us to process our experiences from the safety of a dream world, meaning that
we don't have to deal with the hormone levels that would usually be caused by a frightening
or upsetting experience, and allowing our brains to log it away and learn from it properly.
This is why you can wake up from even the most terrifying dream and not remain scared
by it for any longer than a couple of seconds.
If we don't sleep, our brain function quickly begins to deteriorate.
In fact, just 17 hours awake will bring brain function down to levels similar to how it
works when we’re over the legal drinking limit.
Extended periods of sleeplessness will eventually cause disorientation, hallucinations and eventually
death.
The world no-sleep record currently stands at 11 days (not under torture!), and by the
time those 11 days were up, Randy Gardner, the test subject, was convinced that he was
a famous soccer player.
2.
Left Handedness
Only around 10% of the human population is left-handed and we're not entirely sure why.
The fact that humans favor one side over the other is baffling enough to scientists, as
most of the rest of the animal kingdom do not display any preference to one side, apart
from some apes and, weirdly, polar bears who are generally left-handed.
What we do know is that left-handedness is a genetic trait, but that's not really the
confusing part.
Even with the abnormal asymmetry taken as a given, the statistics in themselves are
also a little surprising.
Archeological evidence suggests that the 10% figure for lefties has remained pretty much
steady throughout history.
This means that we're not just seeing either the tail end of a dying breed, or the beginning
of the left-handed uprising, but a consistent, if small, section of society with a left-handed
preference.
Another curious thing is that lefties' brains are not always wired the opposite as a right-handed
persons.
Often, a lefty brain is the same as the brain of right-handers.
Curiously you can be left-handed but also right-footed, and many right-handers are left-footed.
Generally speaking, you would have thought that with such heavy right-handed dominance,
the recessive left-handed tendency would have died out by now, but it hasn't, even with
all of the weird societal taboos and fears that have arisen around left-handed people
throughout history.
1.
Laughter
Despite the fact that it's something we do every day, scientists aren't entirely sure
why humans laugh.
There are only a handful of species on the planet that do it.
Despite that fact that many other animals also have complex social structures like our
own, they appear to be largely humourless.
It appears to be most similar to the panting sound made by young apes when their parents
tickle them, but seeing as we're equally in the dark as to why they do that, it's not
all that helpful.
Also, laughter isn't necessarily anything to do with humour, anyone who has politely
sat through their father-in-law's jokes will attest to that.
It is reckoned that only around 20% of laughter is in response to an actual funny joke or
a stimulus like tickling, the rest is made up of the polite guffaws and awkward giggles
that punctuate conversation without anything really being funny.
It is also thought that perhaps laughter is used as a way of controlling the behaviour
in our social groups.
The difference between "laughing with" and "laughing at" someone could be the key to
this.
When you laugh at someone, you are essentially telling them that their behaviour is not acceptable
to your group, either pushing them out or forcing them to alter it, whereas "laughing
with" is a signal that the behaviour is accepted within the group.
The fact that humour plays a role in sexual selection - you know the ladies appreciate
a sense of humour, it could be the reason for its prevalence in humans.
It could be a successful trait passed down through generations.
Thanks for watching!
Were you surprised by any of these?
Let us know in the comments below!!
Be sure to subscribe and see you soon!