(sipping) (exhales deeply) - Water, easily explainable, right? Maybe not so much. You live in a world where science can basically explain everything or at least that's the way that it seems. The truth is, despite the human race being more technologically-advanced and scientifically
knowledgeable than ever before, there are still many things
that remain unexplained. But I'm not just talking
about complicated things but in fact, some of the simplest things. (dramatic whooshing)
(insects chirping) Here are 10 simple things
that science can't explain. (dramatic whooshing) Number 10 is water. (birds chirping)
(calm music) Water shouldn't be much of a mystery considering there's so much of it and humankind has been studying it for pretty much the entire time that our species has existed. But those oceans hide
secrets beyond the creatures in their depths. For instance, how exactly
did they get there? Though, the sun would've been
far smaller and thus cooler, somehow, billions of years ago, water existed in a liquid
form on the Earth's surface. A number of theories have been offered but nothing concrete exists as to why. Another mystery about the common fluid involves its colder form. Normally in matter, when
something enters a liquid form, it condenses in size. Heat expands things, not cold. So why does the same amount
of water when frozen, take up more space? Again, scientists only theorize! That makes a lot of sense
and it also explains to a lot of you who
wonder why I'm only 5'6", it's because I'm here in California where it's hotter so I've shrunk. I was a lot taller in
Canada where it's colder. I swear! (dramatic whooshing) Number nine is the placebo effect. (birds chirping)
(calm music) There are plenty of medicines out there that have changed the moods, outlooks, and obviously, health
of those who take them and there are plenty of
non-medicinal sugar pills out there that somehow mysteriously
have similar effects. This is called the placebo effect which is basically fake medicine but when taken by an individual who believes that they're
taking the real stuff, somehow delivers a similar effect to it. It's often used in drug trials where the participants don't know if they're getting the real drug or a placebo disguised as it. Though doctors are grateful to see their patient's lives improved, they have little to no
explanation for why exactly believing that you're getting better or suffering from side effects
has the unexpected result of actually making you that way. Wait, that can happen? I have hair, I have hair, okay. Yes, guess I have to think
a little harder about it. Number eight are the
number of animal species. (birds chirping)
(calm music) Science encompasses some pretty advanced and mind-boggling things but one of its biggest
mysteries involves counting. With the world's
population growing everyday and thus, more people
giving into the travel bug that's in their souls, it's hard to believe that
there's really anywhere that we haven't been or for that matter, creatures that we haven't documented. But according to experts
in zoology and taxonomy, we may have only scratched the surface on the number of animal
species that exist today. Apparently, around 15,000 new creatures are discovered every year
including the Baldo Raptorous. (squeaks) And we're not talking about
previously found animals with different colored stripes but actually genuinely new ones. It proves that not only
does science not know how many creatures share
the planet with us, but it's possible that we
may never actually know what the number is as it's always growing. Number seven are plants. (birds chirping)
(calm music) Prepare to never look at leafy
greens the same way again. For many years, the scientific
community has been arguing about a topic that will
likely surprise you. Are plants intelligent? It seems like a no brainer, literally, as plants don't posses brains. So they should be unable to think. However, a number of studies have proven that at least some plants can
communicate with each other, all be it, in very simple ways. For instance, when under
attack from herbivores such as insects, some
trees have been documented, somehow sending warnings
to other similar plants which then work quickly to make
a chemical deterrent to them so that they're not eaten as well. Just how the messages are sent or if they're truly being sent at all are still being debated. I knew it, I knew it! After seeing Lord of the
Rings, I was like Ents exist. There's this tree people and
they're talking to each other. Sorry, conspiracy
theories is another video. Number six is yawning. Like almost every vertebrate
on planet Earth, humans yawn. It's been labeled as sign that we're tired while at the same time, a
socially contagious action. As when you see someone
yawn, you often do too. (yawning) Did it work? But how can that be? If you're not tired but someone
else's yawn makes you yawn, does that mean that you're suddenly tired? This question and many
others have caused scientists to admit that they don't
know what's going on here. Hundreds of years ago,
ancient humans believed that yawning increased the amount of air coming into our bodies and
thus, our blood stream. but it seemingly does no more
than a deep breath would. In fact, research shows that a yawn can actually reduce your oxygen levels. Another theory suggests they cool our brains and spinal fluid but still nothing's concrete. (yawning) For real, though. (yawning) Did it work that time? Seriously, let me know in
the comments, I wanna know. Number five is ice being slippery. (birds chirping)
(calm music) Hailing all the way from Canada, I assure you that the winters
there can be a real nightmare, bringing along with them not only a frustrating amount of snow but also the constant risk of slipping as well as falling on patches of ice, something that I've done before. It's not fun. But if you were to ask someone why ice, even outside of Canada, is so slippery, they can only speculate. Amazingly, in the realm of physics, there's no real reason
for why ice is slippery! We know that physically,
it's likely because of a very thin layer of water that sits on the top of a block of ice but there's really no reason
for that liquid to be there. Clearly, the temperature is
cold enough for it to freeze but still, we slip! Multiple theories have been offered but like any good mystery, it's yet to be sufficiently solved. Also, the bigger question here, are bananas really slippery 'cause you see 'em all
the time in cartoons, people breaking their backs. Don't try that at home but
if you did, let me know. Number four are bicycles. (birds chirping)
(calm music) Okay, this one's gonna blow your mind but you know bicycles, those
two-wheeled transport machines that you sit on and
pedal to get from A to B? Yeah, well, scientists can't
tell you how they work. When those training wheels
finally came off your bike and you managed to learn how
to ride it on just two wheels, you probably figured it was
just good balancing on your part but if you hold a
riderless bicycle upright and give it a push in a
straight forward direction, it will still travel at a good distance before succumbing to gravity. But the question is why? Some have claimed that it's just forward
motion keeping it stable but physicists say that
it's not that reason either. In fact, it's a mystery! So when someone tells you that something is just like riding a bike, they probably mean the task is doable but completely impossible
according to physics. Okay, that's probably not what they mean but you get the idea. Number three is gravity. (birds chirping)
(calm music) There's a force holding us to
the ground beneath our feet, the same force that all matter
has towards other matter. It does everything from
pull apples down from trees to forming entire galaxies and yet, scientists can't explain why or how it exists! It's been well-documented
and for over four decades, scientists have been
experimenting with it. Their only conclusions are
that it most certainly exists in all matter but they're
lost as to what causes it. Gravity is one of four fundamental
forces in the universe. The other three being strong,
weak, end electromagnetic. Those three make sense in
physics but not gravity! Though we should be
obviously be grateful for it as it keeps us from floating
off into certain doom! (demonically laughing) What makes gravity work is a mystery. Number two is why we sleep. (birds chirping)
(calm music) Sleep's pretty great. It lets us get away from the stresses of our daily lives and just be horizontal for a while but why exactly do we need it? We feel tired and the side effects of not getting any for a
while can be dangerous! However, the definitive reason
for the required activity still escapes even experts. Though it's widely believed that we sleep so our brains can shut down, the reality is very much that they don't. In fact, some parts of the
brain become more active when we're unconscious. One theory for this suggests
that our brains interpret and store the memories that we've created throughout the day, cataloging them for future retention. While another says that sleep is needed to reenergize the brain
without active input. Maybe it's both but the fact
is, we still don't know. And number one is time. (birds chirping)
(calm music) You might think of it as money and there might not be
enough of it in a day for you to accomplish
everything you want to but time is just a
theoretically endless sequence in which every event is contained but the thing is, it's
just that, theoretical! Time is intangible and
some geniuses believe that it's not even really happening. In physics, it's considered
simply what a clock's face reads as its existence is yet to be fully proven and yet, time is used to
establish measurements in things like velocity,
astrology, and navigation. Think about that. Physics says it cannot
establish time as a true thing but uses it to quantify other things! So the next time someone
asks you, what time is it? You can be super sassy and reveal that there
may not be time at all or if you meditate like me,
all there ever is is right now. (dramatic swooshing)
(calm music)
