We Are All Related - Vsauce

LINKS:

http://www.Twitter.com/Tweetsauce
http://www.Facebook./com/VsauceGaming
Vsauce Tshirts: http://www.districtlines.com/vsauce
music by: http://www.Soundcloud.com/JakeChudnow

Bill Bryson's "A Short History of Nearly Everything": http://www.amazon.com/A-Short-History-Nearly-Everything/dp/0767908171

We're all related (Wikipedia): http://en.wikipedia.org/wiki/Pedigree_collapse

Most Recent Common Ancestor PAPER: http://tedlab.mit.edu/~dr/Papers/Rohde-MRCA-two.pdf

Most Recent Common Ancestor data excludes uncontacted peoples: http://en.wikipedia.org/wiki/Uncontacted_peoples

H Twins SCALE OF THE UNIVERSE (interactive): http://htwins.net/scale2/

Our atoms get replaced: http://askanaturalist.com/do-we-replace-our-cells-every-7-or-10-years/

TIME article on atom replacement (pay-gate): http://www.time.com/time/magazine/article/0,9171,936455,00.html

The paradox of atom replacement and identity: http://en.wikipedia.org/wiki/Ship_of_Theseus

1 billion sodium atoms: http://answers.yahoo.com/question/index?qid=20120228021643AACTqbF

How many atoms are in our body?: http://www.physicsforums.com/showthread.php?t=122923

Ehi Vsauce, Michael here and you guys

are my family.

Scientifically speaking, geneticists tell us that

every single person on Earth is at the least 50th cousins with

everybody else on Earth. It kind of has to be that way.

Thinkin' of it like this: you have two biological parents and

four biological grandparents and eight biological great-grandparents and

it keeps doubling.

Well, if you follow your family tree all the way back to

the time of the ancient Romans, 64 generations ago,

that tree will need one quintillion separate individuals,

which is a number that is larger than

the number of humans who have ever existed ever.

So what does that mean?

Well I think Bill Bryson put it best when he said

"You couldn't be here without a little incest -actually

quite a lot of incest".

Nothing ridiculous mind you,

but if you go far enough back in your family tree

you are going to find that quite frequently people who

were distantly related had kids.

In fact, if you are currently dating or married to somebody

who is from your own country and is of your own ethnicity,

there is a one in five chance that the two of you share

a common family member fewer than ten generations ago.

Furthermore, because our society is becoming more and more mobile,

our most recent common ancestor is becoming more recent.

Mathematical models are now showing us that for everybody,

every human on Earth right now,

our most recent common ancestor probably lived

only 2,000 to 4,000 years ago. A recent study

-it's a great one you should read it-

found that there was a person alive as early as 300 BC

who is related to every single person alive on Earth today.

That study also found that that person most likely

lived in Taiwan, near a busy port city so that ascendance

could quickly spread around the world.

Now all that said, you only receive half of your genetic information

from your mother and half from your father and

as you go up your tree it's quite possible that

distant and distant ancestors had literally no contribution to your genome.

So, who are you?

Have said this before but, because bacteria are

so much smaller than the average human body cell,

your body contains more bacteria than it contains its own cells.

And forget about trying to remember

every individual cell and bacteria in your body,

they're constantly dying and being replaced.

Even cells like brain cells which seem to live for a very long time

still take in new nutrients and expell waste, meaning that

within about every five years every single atom that

used to make up your body has been exchanged.

Do you remember what you were like 5 years ago?

Well, the atoms that make up your body, they sure don't.

This is a little existentially scary but

it leads to a very good question:

how many atoms are inside my body to begin with and

how much is a billion atoms?

Well, here's one way to think about this.

If you were to count one number greater every second

it would take you 12 days to count to a million.

And if you wanted to count to a billion, that would take you 32 years.

So a billion is a very large number, but not when it comes to atoms.

Atoms are so inconceivably small that even if you had a billion, say

Sodium atoms, their entire weight would only be 38 thintograms.

Each individual cell in your body, too small to be even seen by the eye,

contains 100 times more atoms

than there are stars in the Milky Way galaxy.

Multiply that by the number of cells that make up what

we call ourselves and each human body

contains more atoms than there are stars in the known universe.

Numbers that large lead to some pretty mind-blowing truths,

for instance, this one mentioned by Bill Bryson.

Because our bodies contain so many atoms, and because we so

vigorously recycle them, statistically speaking

about one billion of the atoms inside your body used to belong to Shakespeare.

A billion of your atoms used to belong to Beethoven,

a billion of the atoms in your body

right now, as you sit and watch this, used to be

inside the body of Buddha.

You could also think of it this way. A thousand years from now,

when humans first land on a planet outside of our Solar System,

that first person to step under the surface of the alien planet,

that body will contain a billion atoms, that are in you, right now.

And as always, thanks for watching.