Hey, Vsauce. Michael here.
Ten centimeters – about four inches.
This is how much taller on average people are today than they were 150 years ago.
Better nutrition and medical care early in life has allowed us to better
take advantage of the blueprints within our genes.
Blueprints that carry plans for just how big a healthy human being can get given an optimal environment.
In terms of height, those plans rarely exceed 7 feet 6 inches. But individuals with endocrine disorders,
for instance a tumour, near the pituitary gland in the brain
can experience growth that occurs more rapidly and for a longer period of time than usual.
For instance, Igor Vovkovinskiy, who at 7 foot 8 inches is the
tallest man currently living in America.
The tallest living person anywhere on Earth is Sultan Kösen, who at 8 foot 3 inches tall also holds the Guinness world record for largest hands and feet.
But the tallest person ever officially recorded was Robert Wadlow. He was the size of an average adult male
when he entered kindergarten at the age of 5.
When he died in 1940 at the age of 22, he was 8 foot 11 inches tall.
Andre the Giant was 7′ 4″.
And this is me holding a 12-ounce can. Here’s Andre doing the same.
Human size variation is fascinating, but what’s the maximum, biologically how big can a human get?
And more importantly, how big are you really? It turns out that today, now in history, average human height is probably quite near the genetic limit.
By manipulating the very genes responsible for height, we may be able to add an extra 15
centimeters or so to that average, but beyond that we are likely to hit a ceiling.
In order to regularly produce people over 8 feet tall, 2.44 meters, those people would probably need to be a different shape.
Not human shaped. This is because of the square-cube law. As a shape grows, say, taller,
its volume increases at a greater rate. Take a look at this cube.
If we make it 10 times larger, well, sure, it’s 10 times as tall,
but the area covered by its faces is 100 times larger and its volume, the space within it, is 1000 times larger. Now, since weight is connected to volume, this cube only has one hundred times the
cross-sectional area to support itself, but one thousand times the weight to support. So, if you were ten times larger, and still shaped like a person, that is
your proportions were the same as they are now, you would need to either have a skeleton
made out of something stronger than bone or bones that were monstrously thick,
like way out of proportion. But even if you solved the bone and
muscle strength problem, there would still be a whole host of
other issues. For instance, your heart wouldn’t scale up fast enough to
keep blood pumping throughout a body that large.
Animals can get that big, because their proportions
and organs are quite different. Chris Howard from Earth Unplugged
tipped me off to the giant, not human proportioned, legs of the largest land animal ever known to
have existed with the certainty of a complete skeleton, the awesomely named giraffatitan. Discovered in Tanzania and now mounted
in Berlin’s Humboldt museum it probably weighed 20 to 30 thousand kilograms. The Bruhathkayosaurus may have been even larger, but this is controversial because we
only have a few of its bones. Estimates put this guy at 140,000 kilograms.
Any larger than that, and in order to survive long enough to reproduce, an animal would need more buoyancy to
counteract its weight than air can provide.
This is one of the reasons blue whales love the water so much. The heaviest blue whale ever measured by NMML weighed in at 177,000 kilograms, making it the heaviest animal we are aware of that has ever existed.
It might be the heaviest possible, because animal size is limited
by simple geometry and the gravity of our planet. Theoretically, humans born on Mars could
grow a few inches taller, because gravity there is only one third
of what it is on earth. The trade off of course being that their
bones and muscles wouldn’t grow strong enough for them to ever visit Earth and enjoy it. The point is, in order to have
the same shape and proportions that we have now, we can’t really get that much bigger. Some of the higher estimates of the upper
limit up average human height are around 7 feet tall. A person who is more than 9 feet
tall would struggle to move around. aAd up in the 12- to 15-foot range, it would be difficult to live very long at all. But what does size mean? Where do you really begin and end?
So far we have been measuring people using their rigid boundaries.
It’s a good one to use, it’s very common, but of course, when I speak I can fill an entire room and when I shout I can fill city blocks.
That’s huge.
Of course, my voice is not a part of my physical body. It’s not part of the matter that fits
within my skin container. But it’s relevant to the question of how big a person is.
How large of an impact on their environment can a person
have using what comes directly from their bodies?
Well, Guy Murchie illustrated this quite well in his tome “The Seven Mysteries of Life.” The little solid dogs are small, but their sound and smell extend into
shapes and sizes no creature could even dream of filling up with their bodies on earth. Let’s begin with sound.
How far can your loudest shout travel?
How much bigger are you? The volume of space within which people
are aware that you exist when you shout.
Well, the loudest shout a human can make is about 88 decibels from 30 centimeters away. A shout like that will die out down below
the threshold of human hearing in our atmosphere, after traveling about 5 kilometres or 3 miles.
A person standing downwind from you might be able to make you out a little
further than that, but the point is, in space no one can hear you scream.
And on earth, from 5 kilometres away, no one can hear you scream. But could they see you scream?
Really, could they see you at all?
Well, on the surface of the earth, the furthest you can see another person is the horizon.
If you and another person are standing on the ground, that distance is about 5 kilometers or 3 miles. Any further away than that
and you will literally be hiding behind the curvature of the earth.
So what about in, say, outer space, where moving away
from another person doesn’t mean eventually hiding behind the earth.
Well, as an object moves farther and farther away, it becomes smaller and smaller.
Of course, the actual size of the object doesn’t change.
What does change to you is its angular size.
This brilliant measurement describes how much space in your visual field an object takes up. Imagine your visual field as a complete circle, 180 degrees of which go from the
horizon in front of you to the horizon behind you.
So, an object with an angular size of 90 degrees would have to be big enough and close enough, so as to take up all
the space from the horizon to right above you.
Its size is 1 degree.
The Moon takes up about half a degree at all times.
It sometimes appears larger at the horizon, but that’s because
of an illusion that AsapSCIENCE covered really well.
Te smallest angular size we can see with the naked eye is about one arc minute, a sixtieth of a degree. But given enough contrast,
we can see things like Sunspots, a mere 20 arc seconds across, a third of a sixtieth of a degree.
Plugging in numbers to do the math will tell us that with perfect conditions: outer space, no air, no obstructions,
a lot of contrast, because you are wearing bright white, the farthest away a person could see you with their naked
eye would be about 10 to 15 kilometres. Any further away than that and they will
have passed the edge of your naked eye visibility existence. But… do you smell that?
It might be you.
If we consider the senses of other animals, your smell, your scent, might be your largest earthly dimension. You know how animals like cats and dogs
have those cute little wet noses?
It’s called a rhinarium.
Rhinariums allow mammals to smell really really well.
They don’t just pick up molecules that float by, they localize them.
Air cools the wet nose, allowing the animal to tell the source of the smell. It’s the same as when you wet your
finger and stick it in the air to tell the wind’s direction. A Bloodhound can pick up and trace to you a scent trail that is days old, making your scent imprint on the earth about as large as you can move in a couple days. But the Silvertip grizzly has a sense of smell that is seven times stronger that a Bloodhound. These guys can smell things from 18 miles away, nearly 30 kilometres.
That’s probably the largest bubble we could draw around you and still call you, because it contains things that you omitted that can be
traced back to you by other living things. But if we include everything you emit, well, fundamentally we’re limited to the edges of earth’s atmosphere,
because with the exception of a few light molecules, hydrogen, helium, which escape into space, not much else leaves. There’s no medium in
space for your sound and smells to travel through. Which brings us back to light. The human body emits light,
electromagnetic radiation. Most of it is infrared light, heat.
But some of it lies within the visible spectrum, though it’s about 1,000 times dimmer than
the dimmest light the eye can see.
It seems that what little visible light you do emit is tied in some way to your circadian rhythms, meaning that around 4 p.m. everyday, you are literally visibly the brightest you will be all day.
It doesn’t need a medium to travel through. It just keeps going out into and through space, which of course brings us to Australia. If you’re not subscribed to Derek’s channel Veritasium I don’t know what you’re doing with your life.
It is amazing and he recently made a video that I have
not been able to stop thinking about. The smallest possible piece of light is a photon and the human eye can kind of perceive individual photons,
a bit better than chance. But some frogs can see individual
photons quite well. Now, in his video he explains that,
as you move away from the Sun, its angular size gets smaller and
smaller and smaller, until eventually you’re so far away from the Sun that you
can no longer see it. But it’s still there and it is still emitting light that can reach your eye, except now that light has been spread so thin
it’s not big packets of light you can see, it’s just individual photons. The Sun is still there, it’s just less frequent. Sometimes a photon hits your eye, sometimes nothing and sometimes a photon again. Well, the same thing happens to radiation emitted by you.
I Skyped with Derek this afternoon and he calculated that the human body,
seen at a distance of 168,000 kilometres would also be reduced to merely a few individual photons. Further than that and your size would no longer get smaller, it would just remain individual photons flying through space, they are, after all, indivisible.
So, your physical size is limited by geometry and biology and gravity.
Your vocal and fragrant size can be bigger but it still limited by the size of Earth. But your light, your personal glow, isn’t really bounded by anything. The photons that you are emitting right
now, the ones that don’t get absorbed by anything, have no reason to ever really stop. And they can continue conceivably past
even the observable universe, making you, in a way, completely huge and kind of immortal. And as always, thanks for watching.

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• October 2, 2019 at 11:32 pm

I’m 5 foot 1/2 inch 😂😂

• October 3, 2019 at 1:13 am

what about size in the sense of historical impact

• October 3, 2019 at 2:56 am

bold of you to assume I can see 5km away

• October 3, 2019 at 3:09 am

I don’t think being able to be smelled from 30 km away is gonna help me make the team

• October 3, 2019 at 3:27 am

Aleph null

• October 3, 2019 at 5:06 am

Bruhathkayosaurus

• October 3, 2019 at 6:21 am

the smell depends though. anyone could smell asmongold 30km away

• October 3, 2019 at 2:48 pm

my friend m: how many pees did you take?
me: 12:18

• October 3, 2019 at 2:52 pm

my vampire friend: why should i stop drinking fat people?
me: it's 15:01

• October 3, 2019 at 3:17 pm

4:00 the way you pronounced Tanzania gave me cancer of the balls

• October 3, 2019 at 3:28 pm

A silvertip bear can smell me at 30 kilometers?? WTF??? Their world must smell like SHIT! lol they can smell dead frogs down at the stream, a hare taking a shit up the mountain or even some campers Budweiser…poor thing..not the Budweiser!!!

• October 3, 2019 at 4:01 pm

sometimes the photons tell my father to hit my eye

• October 3, 2019 at 6:01 pm

Dipolodoculus- Ali-A 2018

• October 3, 2019 at 6:21 pm

i'm 11 years old and i'm 177 centymeters tall

• October 3, 2019 at 6:40 pm

My question is.. how would André jerk off?

• October 3, 2019 at 7:17 pm

Meh. If you’re not a 400 meter robot, don’t @ me.

• October 3, 2019 at 9:41 pm

2:10 Of course you're bound to hit a ceiling after a certain level, but you'll also probably hit a doorway too

• October 4, 2019 at 12:33 am

At one point in North America there was an abundance of mega-fauna I am convinced there were also mega-sapiens remains/evidence of which were covered up by the Smithsonian in the 1800's

• October 4, 2019 at 1:50 am

A little over 18 miles for Black Bears I think. A scientist documented one walking 18 miles straight to a dead carcass.

Edit: I know your IQ is still higher..

• October 4, 2019 at 4:26 am

Im 15 and 5'11

• October 4, 2019 at 5:23 am

Could that one frog see its own reflection in a mirror from 168,000km away?
Isn't your reflection always exactly half your size and wouldn't that divide the indivisible size wise?

• October 4, 2019 at 6:31 am

This goes off the topic a lot

• October 4, 2019 at 6:43 am

• October 4, 2019 at 12:05 pm

If we can’t grow higher let’s grow wider

• October 4, 2019 at 12:09 pm

Get gru, he a big boy

• October 4, 2019 at 12:29 pm

Nobody:
The clown on friday the 13th: 7:33

• October 4, 2019 at 4:20 pm

Me: 0:02

• October 4, 2019 at 4:37 pm

You can be taller than 8ft

Antman: Am I a joke to you?

• October 4, 2019 at 6:09 pm

What about the Titanasaurs? they were much larger terrestrial animals.

• October 4, 2019 at 8:34 pm

Dutch people are all time travelers from the future

• October 5, 2019 at 12:06 am

Trying to make people taller through genetic manipulation, above about 6 inches we hit a ceilling
I see what you did there Michael

• October 5, 2019 at 1:30 am

you're so eduicational I love you

• October 5, 2019 at 3:22 am

@1:27 it's crazy to me how normal these girls look. They don't look from that era. It's weird to me how it looks like they were all plucked straight from 2019 and sent back in time. It's also an odd feeling knowing that each one of these little cuties is either dead or an old woman by now.

• October 5, 2019 at 3:22 am

Why is the db of the shout measured from .3 m away?

• October 5, 2019 at 3:39 am

2:38 I find funny how americans rush desperate to metric when there's any sort of calculation needed. Why not do this with square inches and cubic inches? 🙂 Because it doesn't look as neat, nor as intuitive. Maybe we all should switch to metric whimsical music intensifies

• October 5, 2019 at 5:12 am

Render distance 1500 blocks

• October 5, 2019 at 6:20 am

i believe the brofessor has the answer for you

• October 5, 2019 at 6:59 am

Am I the only one who can see and hear at different intervals….

• October 5, 2019 at 7:16 am

why don't you ask my partner herherherherhereeeee

• October 5, 2019 at 7:20 am

Ok my theory is, there was so much oxygen in the world around when dinosaurs were which allowed them to grow to the suitable size which is huge as we can see and when the meteor hit the planet lost that oxygen meaning life had to shrink to the size of how much oxygen is on scale, so if humans were around 100 million years ago we would be adapted to the oxygen levels meaning we could technically grow extremely tall maybe even to the size of an elephant however our body would be a different shape

• October 5, 2019 at 7:31 am

bruhh… there's a dinosaur called bruh?!
4:09

• October 5, 2019 at 9:15 am

Yes, square-cube law and all that. However if the internal physiology was altered sufficiently, could the external physiology remain similar enough to still resemble a human, just three or four metres tall?

• October 5, 2019 at 2:02 pm

My effect is limitless- maybe

• October 5, 2019 at 2:10 pm

Which of course brings us to… Australia

• October 5, 2019 at 2:11 pm

He made ridiculous comedy videos then this philosophy channel. Hes clearly laughing at us now

• October 5, 2019 at 2:14 pm

What? Im immortal? Great!
Lol

• October 5, 2019 at 3:58 pm

• October 5, 2019 at 9:44 pm

10:00 when someone farts and they blame it on you

• October 6, 2019 at 1:58 am

2:02 – Neatherlands? Really? FYI, it's The Netherlands .

• October 6, 2019 at 6:08 am

Ge said in the 6 in, after that will hit a ceiling, took that wuite literally

• October 6, 2019 at 6:31 am

Where's Tan-Zany-A?

• October 6, 2019 at 6:40 am

In less than 10 seconds, he described my penis size

• October 6, 2019 at 9:35 am

But human size is not cube.. Our body is divided into various parts like arms and legs… And cylindrical and, surface area and volume has pi which is infinite..

• October 6, 2019 at 9:37 am

hi Michael! greetings to you from Russia! it is interesting to watch your videos! good for you!) a lot of things to learn! write through the translator, sorry for the mistakes )

• October 6, 2019 at 1:56 pm

how come my peepee longer than my leg??

• October 6, 2019 at 2:30 pm

0:00–0:02

• October 6, 2019 at 5:28 pm

7 miles away no one can here you or can they *vsauce music plays*

• October 6, 2019 at 5:28 pm

Does this universe make my butt look big?

• October 6, 2019 at 5:45 pm

• October 6, 2019 at 6:03 pm

I farted at 10:00 and then he said that

• October 6, 2019 at 7:04 pm

20:34:50

• October 6, 2019 at 9:10 pm

How about using lbs and normal american measurements?

• October 6, 2019 at 9:27 pm

well time to start launching all my photons out into space I guess.

• October 7, 2019 at 12:24 am

• October 7, 2019 at 2:54 am

What curvature of the earth

• October 7, 2019 at 4:32 am

What about the idea of you?

• October 7, 2019 at 10:35 am

Do… You…. Have… To… Shatner… Every… Sentence???
Seriously dude. I had enough by 6 minutes

• October 7, 2019 at 12:55 pm

What I got outta this video is that we are practically the universe. Another thought the phrase "shoot for the stars" seems kinda pointless after this video, cuz technically we are already there…

• October 7, 2019 at 1:13 pm

Hey Michael! V-Sauce here

• October 7, 2019 at 3:15 pm

3:56
Argentinosaurus*

• October 7, 2019 at 5:06 pm

1:47
I don't like the way you ask that question |:

• October 7, 2019 at 5:53 pm

He Buchered my homeland name Tanzania

• October 7, 2019 at 6:06 pm

3:34 …ANimals

• October 7, 2019 at 10:01 pm

Vsauce always reminds me of my dick size somehow…

• October 7, 2019 at 10:09 pm

10:04 is the feeling of every vsauce video

• October 7, 2019 at 10:53 pm

isn't the farthest you can see someone is when the ocean is fairly still?

• October 7, 2019 at 11:03 pm

Hey vsauce here

• October 8, 2019 at 12:28 am

I 13 and taller than him

• October 8, 2019 at 12:37 am

If humans could survive in space could they theoretically grow gigantic ? Like if gravity and weight were a non issue

• October 8, 2019 at 12:40 pm

This video is made in 2013 and it is still more professional than current videos

• October 8, 2019 at 2:15 pm

All joking aside with current diets, Humans, "in certain areas", are getting more volume as in "fatter". Oxygen levels were not mentioned here. That plays a roll. Plants gave us life and we destroy them. We are a "small" minded species. 🌲

• October 8, 2019 at 3:33 pm

5:46, Everyone ever…

• October 8, 2019 at 3:55 pm

6 years on, still don't like the way he says Tanzania in this video.

• October 8, 2019 at 4:39 pm

12:39
Of course it does

• October 8, 2019 at 9:02 pm

this was about physical size… now you're stretching this with visual scent and sound size of a persons influence to be noticed lol. yes it does mean you're bigger than your physical being but lets be honest, the intention was literal ha

• October 8, 2019 at 9:05 pm

feel like this is an inspirational video using science to show to someone depressed… "you are huge, you are light, you influence your surroundings more than ypu know" lol

• October 9, 2019 at 12:55 am

7:32

• October 9, 2019 at 1:48 am

hey

Vsauce

do you use shampoo?

• October 9, 2019 at 3:15 am

8:00 I was on board until you said "curvature of the Earth" there is no curvature of the Earth

• October 9, 2019 at 6:02 am

About half way through you're starting to get off topic…..is this a schizophrenic test dressed up as a high-IQ vid, or are you just prone to wandering onto different topics:?

• October 9, 2019 at 6:06 am

What if my circadian rhythm is fucked. Can I be bright at night?

• October 9, 2019 at 7:43 am

Huh. This video was made before the Argitinosaurus was found

• October 9, 2019 at 10:45 am

I miss vsauce before the internet making him a meme . 😔

• October 9, 2019 at 11:17 am

The intro gave me the wrong idea….

• October 9, 2019 at 11:26 am

I dunno, pretty big.

• October 9, 2019 at 11:42 am

Wat about the giant from japan

• October 9, 2019 at 2:08 pm

Yo mama so fat she needs to stay in water

• October 9, 2019 at 5:02 pm

The Good ol' days 😢

• October 9, 2019 at 5:55 pm

We all know the furthest thing you can sense is the sound a ghast makes

• October 9, 2019 at 7:29 pm

False facts i am dutch so i can be infinitly big