Nova (1974–…): Season 44, Episode 3 - Great Human Odyssey - full transcript

Numbering no more than a few thousand, tiny groups of intrepid humans began to move out of Africa-eventually dominating the planet. How did these early humans acquire the skills, technology, and talent to thrive in every environment on earth? Takes a global journey through the past, following our ancestors' footsteps out of Africa along a trail of scientific clues to help unravel the mystery of how we got where we are.

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That Homo sapiens,
our species, survived.

For 200,000 years,
the odds have been against us.

MATISOO-SMITH:
We are not indestructible.

There are evolutionary
dead ends.

There are some species
that don't survive.

NARRATOR:
Our ancestors not only survived,

they spread into every corner
of the globe.

GENEVIEVE DEWAR:
Only Homo sapiens were able

to migrate in and colonize the
world's most difficult terrain.

NARRATOR:
Even places forbidding
to any form of life,

they found a way.



WULF SCHIEFENHOVEL:
If you are not resourceful,

you die.

NARRATOR:
Follow anthropologist
Niobe Thompson

as he travels the globe

retracing our remarkable
human odyssey.

My name is Niobe.

NARRATOR:
He's looking for echoes
of the past

in the skills of people

living in remote
and demanding environments,

conditions our ancestors
had to surmount

on their journey to everywhere.

How did our greatest
of grandparents not only survive

their treacherous world,

but ultimately become
our planet's dominant species?



WILLERSLEV:
What you really find out,

they were capable
of amazing things.

NARRATOR:
"The Great Human Odyssey,"
up next on NOVA.

♪ ♪

NARRATOR:
Our species: Homo sapiens.

There are now more
than seven billion of us

living all over the world.

In every nook and cranny,

on every continent,

in places where the living
is easy and where it is harsh

and unforgiving.

We look different,

our skin
various shades of color...

Our children
a palette of their parents.

But under the skin our DNA
varies only a tiny fraction

from person to person because
we are the same species:

Homo sapiens.

JOHANSON:
Globally everyone
is Homo sapiens.

If we're united by our past,
united by our present,

we are certainly united
by our future.

NARRATOR:
We evolved for millions of years
from more primitive creatures

becoming Homo sapiens
only about 200,000 years ago.

Until recently, much of
our ancestors' early history

remained a mystery.

BERHANE ASFAW:
They never left any,

any records for us.

No video records, no pictures.

What they left for us
is their bones.

NARRATOR:
But now new discoveries
are beginning to reveal

their complex evolution,

their strategies for survival,

and their seemingly relentless
drive to reach everywhere.

Understanding how our ancestors
accomplished this feat

is driving anthropologist
Niobe Thompson

on his own around the world
journey.

That looks like
a hand axe to me.

NARRATOR:
He's exploring important
archaeological sites,

and observing the world's
last hunter-gatherers

to understand how our ancestors
were able to conquer

every environment on earth.

Our species has the unique
ability to live almost anywhere,

any climate, any temperature.

One species, everywhere.

That's astonishing.

But that's not how our story
began, far from it.

NARRATOR:
In the beginning,
Africa was our only homeland.

And East Africa's
Great Rift Valley may have been

the very place
our species evolved.

Here, more than
three million years ago,

a creature named Lucy
walked upright as we do,

yet her brain was no bigger
than an orange

and she climbed trees
like an ape.

Over time, a bewildering array
of ancestors

evolved more human-like
features,

but remained small brained
and very primitive.

By two million years ago,
bigger-brained creatures

like Homo erectus emerged
and began making larger

and more sophisticated
stone tools.

ASFAW:
Once they start using
stone tools,

that means they had access
to high-energy food

that might have triggered
the expansion of the brain.

NARRATOR:
Stone tools helped early humans
butcher animals

they killed or found.

And consuming more meat
helped power a growing brain.

That food source is very
important to feed our brain,

which needs a lot of energy
to maintain.

NARRATOR:
Eventually there appeared
a creature with a brain

and body type like ours.

Our Homo sapiens ancestors
had finally arrived.

But uncovering fossil evidence
of these early ancestors

is extremely rare,
as Ethiopian paleontologist

Berhane Asfaw
knows all too well.

ASFAW:
One of the reasons why we
are not getting so many humans:

the population is so small.

It's very small.

NARRATOR:
And that's why this skull
is so important.

Discovered near the
Ethiopian village of Herto,

at 160,000 years old,
Herto Man is the most complete

early human skull ever found.

He was unearthed
in the dry Middle Awash region

of northern Ethiopia.

Stay to this side.

See the ridge running up there?

All the sand stones
in here have fossils.

Stay within 100 meters of me.

(speaking foreign language)

NARRATOR:
Over the years,
an international research team

has found important
pre-human fossils in this area

of the Rift Valley.

Then in 1997, Berhane Asfaw
noticed bone fragments

that looked distinctly human.

ASFAW:
It's a child skull

shattered into 160,
over 160 pieces.

NARRATOR:
Finding fossils
crushed into pieces

by time and geologic forces
is not unusual.

So the team was astounded
when they found a nearly intact

adult skull which they carefully
wrapped for conservation.

(groans)

Perfect jacket.

NARRATOR:
Instead of the low forehead
and protruding brow ridge

of earlier species,
Herto Man has a flat face

and the distinctive round
braincase of Homo sapiens.

ASFAW:
The brain has expanded
and the face has shrunk.

It is basically a
brain-dominated individual.

All the features that it has
is exactly us.

NARRATOR:
An artist's rendering
suggests that Herto Man

would have resembled
a modern man from Africa.

But what do we really know
about him?

How did he live his life?

Today, the Herto region
is dry for much of the year

and looks like it could
hardly support any life.

But excavations have uncovered
numerous animal remains

and stone tools from a time when
the valley was far more fertile.

The Herto of our ancestors
had rich vegetation

and a lake that drew
prehistoric buffalo, hippos,

and other game they hunted
for food.

The bones of these animals
have been unearthed.

And they have
an important story to tell.

For example, we see this
cranium of a hippo,

the upper jaw.

We see a chop mark,
which must have been made

using this kind of
large cutting tool

in order to dismember
this hippo.

Humans were repeatedly feeding
on hippo meat.

NARRATOR:
Many of the skulls
were from hippo calves

that were far less dangerous
than full-grown hippos.

But humans
weren't their only hunters.

Deadly carnivores stalked
the lake,

so our ancestors needed
to be tightly organized

to avoid becoming meals
themselves.

Archaeologist Yonas Beyene
has studied all the Herto finds

and can almost visualize how
our ancestors must have hunted.

BEYENE:
These guys must have come
in a team coming in together

and moving out together.

Whatever meat they find,
they encounter,

they must cut it fast
and move out.

And that cooperation
among the group members

must have contributed
to their success as humans

in that difficult environment.

NARRATOR:
Herto tools were more versatile
than previous types--

different sizes and sharpness
for precision and power.

Somebody who makes such kind of
tool has an organized brain--

hunting together,
acting together,

and it is that social behavior,
social culture,

which pushed us,
you know, to evolve,

to evolve to what we are now.

NARRATOR:
By 150,000 years ago,
our ancestors were living

a precarious existence in
small bands of hunter-gatherers

scattered across
the African continent.

100,000 years later,
they are still hunter-gatherers,

but now they're on their way
to becoming

the most dominant species
on earth.

How did this remarkable
transformation come about?

SCHIEFENHOVEL:
We have a problem
of understanding

the power of our own species--

physical powers

and especially
the mental powers.

That is what we have
to understand.

We are an incredible
construction, Homo sapiens.

NARRATOR:
But we almost didn't make it.

Throughout the years
of our ancestors' emergence,

there were severe climate
changes.

Large swaths of Africa
became bone dry,

forcing animals and people
to seek more fertile ground.

How did our ancestors survive
these environmental crises?

What did they do
when the food and water ran out?

They clearly made it
because we are here.

The question is:
how did they do it?

Niobe Thompson has come
to Southern Africa's

Kalahari Desert to meet
and observe the San Bushmen.

Niobe.

Obe.
Obe.

Yeah.

NARRATOR:
Although many of the San
have been moved

out of their traditional
homeland,

small groups continue

the resilient ways
of their ancestors.

Anthropologists like Niobe have
been observing such societies

for decades trying to understand
their social, cultural,

and spiritual beliefs,

and how they live
their day-to-day lives,

from the food they eat to the
natural medicines they use.

Living in one of the world's
driest environments,

members of this group can still
survive in traditional ways.

Niobe accepts an invitation
to follow the men on a hunt.

This will give him
a rare opportunity to see

if these hunters
display strategies our ancestors

might have used to find food
in this desolate landscape.

One of the techniques the
San are known for is called

"persistence hunting."

Humans are not built
to be natural killers

like the great carnivores
of Africa.

They haven't the speed,
power, teeth, or claws.

We also do not have
much body hair,

and that's to our advantage.

In the hot sun, lions
and other fur-covered animals

need to release body heat
by panting or sweating

through their tongues.

Humans can sweat from all parts
of the body, and by doing so

can endure
the intense heat longer.

Hunters like the San
can't outrun faster animals,

but they can outlast and exhaust
them before making the kill.

It is very possible our
ancestors hunted just this way.

There are few game animals
in this area of the desert,

but enough so Niobe can observe
the San's skills first hand.

We've been walking for
only for an hour now.

And what I notice is that
they are always looking down.

They are not scanning
the horizon to see the animals,

they're looking for their tracks
in the sand.

It's like they're reading
a book.

NARRATOR:
And they can still find
their prey.

(panting)

THOMPSON:
Yonas has found a spring hare.

They hooked in through its den
using their long hooked stick.

NARRATOR:
Once they've secured it,
they have their dinner.

But survival for desert people

has always been about
finding water.

THOMPSON:
We all share a voracious
appetite for water.

Our kidneys were evolved
in a jungle environment,

and so they're designed to flush
two liters of water a day.

So what would our ancestors
have done in place like this,

the Kalahari,

which sees no rain
for nine months at a stretch?

NARRATOR:
The San know the desert plants
that have an ability

to retain water--
like the Kalahari water tuber--

which can be shaved
and then squeezed

for its precious liquid.

Wherever and however
they find water,

the San know how to store it
in ostrich egg sip wells

for even drier times.

DEWAR:
You drill a hole
in one end of it,

you make it an empty vessel.

And if you find a water source
you can easily fill up

these ostrich eggshells.

And so if you're able
to carry around large number

of these ostrich egg shell
flasks,

you have a constant source
of water.

You could even
like a Hansel and Gretel,

be leaving yourself a pathway
of stored water.

Then who knows how far
you could travel.

NARRATOR:
Archaeologists
have unearthed fragments

of ostrich egg sip wells
from 100,000 years ago,

so the San are indeed
using an ancient technology

borrowed from the past.

DEWAR:
I think this is

one of the most remarkable
hallmarks

of our amazing brains is that
we can easily come up

with innovations to move
into these extreme environments.

NARRATOR:
Niobe returns to the village
where women are milling

Mongongo nuts
into a tasty paste.

Like wild game, nuts and berries
were also the food

of our ancestors.

But the San
are 10,000 generations removed

from those ancestors.

So their lives
are really quite different

than they would have been
in the past.

These desert people
have clearly retained

the kind of adaptability our
ancestors must have possessed

to survive in such
dry environments.

But even this kind
of resourcefulness

may not have been sufficient.

For there were times
when drought became so extreme,

parts of Africa turned virtually
unsustainable for human life.

CHRIS STRINGER:
So n times of great aridity.

human populations,
with their need for water

would have just disappeared from
large areas of the landscape,

and shrunk back to the places
where they could survive.

NARRATOR:
Where the drying rivers
and disappearing grasslands

of the interior made life
virtually impossible,

some of our ancestors
began searching for a place

that could sustain them,
and they found it by the sea.

♪ ♪

It was here along
South Africa's rocky coastline

that bands of early humans
would discover new sources

of nourishment and possibly

something critical
about themselves as well.

High up this cliff face,
in a cave near Pinnacle Point,

archaeologists
are uncovering evidence

that around 100,000 years ago,

early humans found refuge here.

And perhaps ideal conditions
for an unprecedented expansion

of the human mind.

Niobe has come to Pinnacle Point

to meet lead archaeologist
Curtis Marean.

CURTIS MAREAN:
I thought that coastal life

would be a refuge

primarily because the sea
is still productive.

NARRATOR:
And the plains beyond the sea

were fertile with wild game
and edible plants.

MAREAN:
So you have the plants,

the animals, and the seafood.

And those three things together
make for the ideal conditions

for the refuge.

NARRATOR:
Curtis Marean has found evidence
of several periods of occupation

now made visible in the
excavated layers of sediment.

MAREAN:
So this is an intact
hearth feature,

a place where about
80,000 years ago,

somebody came in and built
a hearth, cooked shellfish,

got up and walked away.

♪ ♪

(birds cawing)

NARRATOR:
The sea was a bountiful resource
for fish and shellfish--

both nutrient-rich foods
for the mind as well as body.

JOHN PARKINGTON:
Rather than thinking of it

that when we got smart,

we noticed that there were
all these shellfish lying around

and so we started to eat them.

Well maybe it was
the other way around.

Maybe it was
our regular consumption

of all those shellfish
that provided the nutrients

for the brain
to become better wired.

NARRATOR:
Whether it was seafood or just
an abundance of all food,

ancient humans seemed
to have thrived here

as evidenced by the many things
they left behind.

MAREAN:
There are 220,000 plotted finds.

Every individual point
contains data

about the nature
of that artifact.

And every one of these
little dots is an object

that was relevant
to human behavior.

So a lithic artifact,
a stone tool artifact,

a piece of shell, a piece
of bone, a piece of ochre.

NARRATOR:
The team found stone tools
typical of those

made by early humans.

And they also discovered
thinner blades made from a stone

called silcrete.

These slim, sharp points were
thought to have been invented

thousands of years later.

But the team is finding hundreds
of them here at Pinnacle Point.

Experiments show that
ancient humans heated silcrete

to very high temperatures.

After the rocks cooled,
they could be flaked off

in thin, razor sharp pieces.

MAREAN:
They're little tiny blades.

And the wathey were mounted
is you would take a dart--

so maybe something made
out of bone or wood,

you'd grind a slot into it, and
glue these little sharp blades

into that, and the whole idea

is true projectile
technologies--

spears throwers,
or bows and arrows.

NARRATOR:
Now, humans could stay at
a safe distance from their prey

and increase their effectiveness
as hunters.

MAREAN:
A human operating
with true projectiles,

they can dominate the planet.

NARRATOR:
To Marean, projectile technology
was a major breakthrough.

These are
multi-component tools.

So you need to know
how to make a blade.

You need to know how to make
the glue to insert it...

We're talking about a process,
a recipe right?

Right.

The whole thing is
a long recipe that's complex.

And how do we pass on recipes--
language, instruction.

And so if you don't have
language and instruction

and the ability

to hold a number of
data bits in your mind,

then you can't put those
complex technologies together.

NARRATOR:
Living amidst the rugged beauty
of South Africa's coast,

early humans created
a new blade technology

that reflected the expansion
of the human mind.

And in another cave--
called Blombos--

there is evidence
of an additional breakthrough.

Here, excavators are finding
large quantities of ochre--

our earliest paint.

It's made from crushing rocks
containing natural pigments

like reddish iron oxide.

CHRISTOPHER HENSHILWOOD:
You can look at the vast amounts

of ochre in here that's been
worked to produce powder

to make a pigmented compound,
a paint essentially,

using quite complex chemistry,

certainly complex
for 100,000 years ago.

For what?

They didn't eat it,
I don't think.

They didn't hunt lions with it.

They were probably painting
their bodies with it.

NARRATOR:
The appearance of art
has often been linked

to the emergence
of symbolic language--

a critical development in the
modernization of our species.

And Henshilwood's team has found
intriguing carved symbols

that were etched on a chunk
of ochre 75,000 years ago.

HENSHILWOOD:
The engravings are quite simple.

They're cross hatchings.

Writing's perhaps not quite
the right description.

But it's certainly a symbol
that meant something,

so it would've been
an early form of communication,

or if you want to call it,
writing.

That is a breakthrough.

That does not happen
at earlier stages.

Do you think that the people
in this cave were speaking

to each other?

Oh absolutely.

I think people were
talking to each other

on a regular basis.

How did they transmit
all of this knowledge

about the environment?

About which plants
you can eat?

About which fish
is poisonous?

They could certainly plan
for the future.

So these ochres were
an important part of life,

and they're telling you
that the human mind

was not just concentrating
on getting down

and trying to find some food
every day.

But the human mind was almost
as advanced as we are today.

NARRATOR:
To Henshilwood
and other experts,

art is the fingerprint
of a species becoming modern.

RICK POTTS:
One of the things that being
a symbolic animal does

is that it allows us

to refer to the past,
think about the present

and what's going on,

and to imagine what the future
may be and how we may act

to ensure our own survival.

NARRATOR:
To ensure their survival,
did humans begin seeking

more nourishment from places
they had never been before?

There is evidence that
the South African cave dwellers

were eating fish and shellfish
that live deeper in the ocean.

NSHILWOOD:
So we need to look at a scenario
that people were in fact

not afraid of the ocean.

It would start off
with probably the near shore,

but over time we can see
that they're also going

for deep-water species
like abalone.

Abalone are not easy to find

unless the water
is really, really low.

So the possibility is that
people could go into the water,

they could dive.

But you need to go under the
water to get those shellfish.

NARRATOR:
If our ancient ancestors
became deep-sea divers,

how exactly did they do it?

One clue may lie with
hunter-gatherers today

who, like the San Bushmen, could
give us a glimpse into the past.

Niobe has come to remote Tawi
Tawi in the southern Philippines

to observe the Badjao.

The Badjao are completely
adapted to life by the sea.

Their children are taught
to swim

almost from the moment
they are born.

This is Santarawi, one of e
last of the great Badjao divers.

As a young man,
he could hunt underwater

for five minutes at a stretch.

He can't stay submerged quite
as long now, but at age 63,

he's still remarkable.

Niobe is the first westerner
Santarawi has ever met.

Niobe.

NARRATOR:
But the old diver has agreed
to take Niobe deep into the sea

to show him his skills.

(speaking foreign language)

Good.

NARRATOR:
What the Badjao are masters of
is something called

"breath hold diving."

To observe them firsthand,
Niobe has trained a long time

for this day.

Wearing a full wetsuit,
he's going to follow Santarawi

and his son to a reef
about 80 feet below the surface.

At this depth,
a body no longer floats.

The hunters can walk
atop the coral.

When they're truly hunting,
these men would spear fish

or catch other sea animals,

diving again and again
to increase their haul.

After two minutes,
Niobe is desperate for air.

(gasping)

But Santarawi
is still quite comfortable,

even in this intense
water pressure.

His extraordinary control
seems almost superhuman.

People have been diving
to 100 meters on one breath

and remember they have to swim
back up to the surface again.

NARRATOR:
That's about 300 feet--
almost four times deeper

than Santarawi is now.

SCHAGATAY:
Very, very few
terrestrial animals,

I think probably none,
could do that.

They have a diving response
that is conserving oxygen

for the brain and heart,

the organs that need
a constant oxygen supply.

It's difficult to understand
why we are so good divers,

if we were not forced
by evolution to learn this.

NARRATOR:
Although it's difficult
to tell how extensively

ancient South Africans
foraged the deep ocean,

they clearly gathered
enough food to sustain

and even grow their population.

As a result, peoples' lives
became more stable,

and this gave them time
to think, and create,

and pass knowledge
from one generation to the next.

JOHANSON:
We're beginning to think about,
what is it that makes us human.

Well, if you look at Lucy,
it's upright walking.

That's the feature
that we share with her.

If you look a little later
in time, it's larger brains,

stone tools, bodies of modern
size and proportion.

Then hominids who lived 150,000,
200,000 years ago,

they're beginning to use
ochre to decorate their bodies,

to decorate each other.

They're making
very rudimentary art.

Once that barrier is broken,

then you feel really separate
from the rest of the world.

We didn't go from being
totally non-modern

to being totally modern
overnight.

I don't believe in the idea of,
let's say a few mutations

in the brain
that suddenly made us modern.

I think it was an accumulation
of modernity that allowed us

to have the behavioral
adaptations that enabled us

to go out of Africa
and eventually spread

to all the regions
where we are today.

NARRATOR:
By 100,000 years ago the human
population of Africa was small--

perhaps no more than 10,000
breeding-age individuals--

living in small bands
scattered across the continent.

They were in the early stages
of developing skills

that would prove invaluable when
they began to leave Africa--

probably following migrating
animals they hunted for food.

But how did our ancestors
leave Africa?

Or more precisely, where?

Around the time
of our ancestors' emergence,

the Sahara Desert
had expanded dramatically,

and along with the deserts
of Arabia,

created a formidable barrier
between Africa

and the rest of the world.

THOMPSON:
You can see how cut off
our ancestors were.

This is our original homeland.

Look at the size of the Sahara
and then Arabia.

Together they form
a massive obstacle,

and yet somehow humans found
a way from here to here.

We just haven't any idea
how they did it.

NARRATOR:
We know early humans found a way

because of an extraordinary
discovery

near Mt. Carmel in Israel.

In the 1930s, while exploring
caves called Skhul and Qafzeh,

English archaeologist
Dorothy Garrod found

ten Homo sapiens skeletons,
all over 100,000 years old.

To this day, these are
the oldest human remains

ever discovered outside Africa.

But how did these people solve
the challenge of the Sahara

and reach the Middle East?

Could they have followed
the Nile River Valley

north across the desert?

Or perhaps crossed
the Bab-al-Mandeb Strait

when sea levels were lower,
narrowing the distance

from Africa to Arabia.

Recent discoveries of hand axes
in the Arabian Peninsula

may indeed point to the Strait
as an avenue of migration

for early human wanderers.

One of those discoveries
occurred here at Jebel Faya,

an ancient settlement site
not far from Dubai.

The scientist in charge

is German archaeologist
Hans Peter Uerpmann.

And what his team is discovering
under this dry surface

tells him this wasn't always
a desert.

The team had found artifacts

from a 10,000 year-old
agricultural society.

But Uerpmann believes
they would find evidence

of far older occupations
if they just dug deeper.

The surface reminded me
of the situation

which I had before in Oman.

And this find
made me think

that we should go down
under the Neolithic.

And they started
below the Neolithic

and all the way down here,
there was nothing.

This is all sterile here.

This was all sterile.

And they startedto complain,

"Why do we dig here,
there is nothing!"

I told them you go down
as far as we can.

What did the workmen think?

Well, they thought,
"He's crazy."

(laughs)

NARRATOR:
As they dug deeper,

they began finding stone tools
like this one.

That looks like a hand axe
to me, Hans Peter.

NARRATOR:
At 120,000 years old, the axe
is about the same age and type

as those used by the
Skhul Cave people in Israel.

Although they have found
no human remains here,

Uerpmann believes the hand axes
prove humans did take advantage

of lower sea levels to cross
into Arabia from East Africa.

UERPMANN:
There was a window at the time

when the sea level was lowest,

but we always think lower sea
levels mean cold conditions.

That's for a while true.

While the sea level goes down
it's cold,

but as soon as it started
to rise it must be warm already.

And wet.

And wet,
with the warmth comes the wet.

NARRATOR:
Uerpmann's team has found
evidence that there was once

flowing water at Jebel Faya.

And this probably attracted
animals and humans.

In fact, it now seems possible
several desert regions

may have been far wetter
in ancient times.

Niobe has come
to the University of Hull

to meet paleo climate expert
Tom Coulthard.

Coulthard has figured out that
a shifting monsoon rain cycle

may have had a significant
effect on ancient Africa.

We've got like a climate model,
a paleo-climate model,

like the models we use nowadays
to model climate change.

Yes.

But transpose back
125,000 years ago.

Every 20,000 years, the earth
kind of wobbles around.

So there's kind of
a 20,000 year cycle.

It's a regular pattern.

20,000 to 40,000 years of
how far north the monsoon goes.

The monsoon belt was probably
about 700 kilometers

further north
than it is at the moment.

So whole parts
of northern Africa

that are present deserts

and receive
next to no rainfall

were receiving
quite a lot of rainfall,

the kind of amount of rainfall
we get in London.

This shift essentially
eliminated the Sahara Desert

as a barrier for humans that
were further south in Africa?

That's right.

Here we have North Africa,
we have this mountain range,

and the rain will fall
on these mountains,

and it wants to flow north,
and that's enough water

to generate rivers

that flow straight across
the Sahara.

NARRATOR:
These rivers may have reached

all the way
to the Mediterranean,

creating green corridors
before drying up once again.

What's really interesting
is 125,000 years ago

is essentially when we first
start to see modern humans

in North Africa,
and even the Middle East.

That's right.

So this climate shift
corresponds with

a really interesting time
in how we think humans

got out of Africa.

NARRATOR:
Did the Skhul Cave humans follow
one of those green corridors

to reach Israel?

We'll probably never know
exactly how

they got out of Africa,
but a bigger question is

did they become
the first of our species

to begin populating
the rest of the world?

Or did they leave Africa,
but die out

before getting further
than today's Israel?

We might know
if the Skhul people

are our out-of-Africa ancestors
if we could recover their DNA

and compare it to our own.

But DNA this old is extremely
difficult to recover.

WELLS:
Over many, many years,
many, many thousands of years

you get a mineralization
process.

So that the once living tissue
becomes like a stone.

And if it proceeds
completely to that state

then of course there is
no organic material left.

There is no DNA for you
to study.

(bell tolling)

NARRATOR:
But a recent discovery
at Cambridge University

may offer some hope.

Almost a century
after Dorothy Garrod

discovered human skeletons
in Israel, an exciting new find

has brought Niobe here.

(indistinct dialogue)

Looking through the collections,
anthropologist Marta Lahr

found an old tobacco tin
that once belonged to Garrod.

And among the bits and pieces,
she found an intact tooth.

This whole part
was missing.

Mm-hmm.

NARRATOR:
With a replica
of a skull's jawbone,

she shows Niobe where the tooth
came from...

They couldn't
quite safely put it in.

It would not have held.

NARRATOR:
...and explains
the find's significance.

LAHR:
At the moment,

to be certain
from archaeology

or anthropology when modern
people first left Africa.

NARRATOR:
But a tooth in good condition
can sometimes yield DNA

when old bones cannot.

And if they got DNA,
they might just solve

the mystery of the Skhul people.

Imagine if we get
genetics out of this.

NARRATOR:
Lahr has sent the tooth
to this man.

He's Danish geneticist
Eske Willerslev,

who's made
a formidable reputation

for decoding ancient DNA.

Everyone's genome
contains an evolutionary history

written in DNA,

which is comprised
of four chemical compounds,

abbreviated as A, T, G, and C.

Inside our cells,
the chemicals line up in pairs

along a twisted double helix
creating a biological code

that runs our bodies.

Patterns in peoples' DNA differ
because of random mutations

that can occur when the billions
of letters of our genetic code

get copied and then passed
from generation to generation.

People who are related will
share similar mutation patterns,

while those who aren't
have fewer similarities.

But embedded
in everyone's genome

are ancient mutation patterns

inherited from our very first
ancestors in Africa.

If Eske can find these patterns
in the Skhul DNA,

this could mean these are
the people who left Africa

and became the direct ancestors
to everyone in the world.

But will the tooth have
any DNA left to analyze?

At his Copenhagen lab,
Eske's team receives the package

from Cambridge
he's been waiting for.

(speaking foreign language)

My hands are shaking, right?

I mean when we talked about,
you know, now we have to drill.

Things can go wrong.

I mean, we know that, right?

When you cut a tooth it can
splinter, whatever, right?

Of course we want to do it,
and we will do it.

Certainly it's one of
the most important specimens,

human specimens,
in terms of understanding

the spread of modern humans.

And maybe it is the most
important specimen, right, so...

NARRATOR:
After a year of searching
for DNA from the tin can tooth,

they had their answer.

(speaking foreign language)

Okay.

(speaking foreign language)

NARRATOR:
Against all odds, they got
an initial hit of ancient DNA.

(speaking foreign language)

Beautiful!

(speaking foreign language)

Yeah, yeah, yeah,
beautiful!

Super beautiful!

NARRATOR:
And Niobe is there
to share txcitement,

and see the results for himself.

What you have here
is the link of the DNA.

WILLERSLEV:
This is the links of the
fragment so to speak.

This peak
is significant.

WILLERSLEV:
This is the marker,
yeah, yeah.

NARRATOR:
The big spike
is merely a marker.

The important data is in
the small bump next to it--

a fragment with a few dozen
chemical pairs

of what looks like ancient DNA.

That bump is around 40 base
pairs, you know,

the where the majority,

at the height of the top
of the bump, right?

NARRATOR:
It's a short fragment and they
will need to recover many more.

But this is a promising start.

I mean how do you feel
about this result now?

It's ancient DNA.

The question is
what ancient DNA is it, right?

I mean whether it's human
that has survived in there.

We can only find that out
by sequencing.

So... but it looks good.

Okay, good.

NARRATOR:
Sequencing is a process
to reveal the exact order

or pattern of the chemical
base letters

in the recovered sections
of DNA.

But they will need to sequence
many more DNA sections

to accurately compare patterns
in the Skhul genome

with our own.

It will be a long process,
and it may not work.

But Eske is pumped up.

WILLERSLEV:
I have to get myself a snuff.

To stem the excitement.

You aren't allowed
to eat in the lab.

(chuckles)

NARRATOR:
But ten months later,
the excitement has vanished.

Geez...

I mean I'm feeling... I mean
it's pretty disappointing.

I'll give you that.

We could see that
the fragmentation of Skhul

was just, of the DNA in Skhul,
was just severe.

And it's so fragmented
that you cannot map it uniquely

in the human genome.

NARRATOR:
But Eske's not prepared
to give up.

WILLERSLEV:
Even though the chance
is not that high,

but there's still a chance,
I think it's worth struggling

until at least
there's no more hope.

NARRATOR:
And Eske does not stay dejected
for long.

He's already working
on another ancient sample

from a different part
of the world,

and this time
he may just crack it.

Although the genetic
relationship of the Skhul people

to us remains elusive...

to experts like Berhane Asfaw,
they are not a mystery.

He believes migrations
like the Skhul people

have been occurring
for millions of years.

ASFAW:
It's not only one time

that these early humans
moved out of Africa.

They have been doing it
continuously.

Like two million years ago,

there might have been
multiple groups of populations

moved into Europe and Asia.

Whenever conditions change,
these prehistoric people,

they are not sentimentally
attached to one place.

They always follow their food.

Then as they are following
their food, before they know it,

they are far from their place
where they used to be.

NARRATOR:
When Homo sapiens began leaving
Africa about 100,000 years ago,

they were actually following
in the footsteps

of more primitive species
that had begun migrating

over a million years ago.

By 700,000 years ago one of
these early bands had reached

well into Europe and Asia.

And by 500,000 years ago,

they had spawned
two human-like species:

a group called Denisovans...

and a robust people
called the Neanderthals.

Homo sapiens would not evolve
until about 200,000 years ago.

There is genetic evidence of
contact among all three species,

but the most momentous encounter
seems to have been between

humans and Neanderthals
in the lands of today's Europe.

Humans entering Europe
about 50,000 years ago

found a landscape far different
than their African homeland.

It was colder
but had bountiful forests...

numerous lakes and rivers,

a land teeming with wildlife...

And even a species of humans

that looked and behaved
differently.

Neanderthals had lived in Europe

long before Homo sapiens
arrived.

But what were they really like?

For years they were depicted
as primitive,

ape-like and unintelligent.

But this turns out to be
a very misleading picture.

KATERINA HARVATI:
It's been calculated

the absolute volume
of Neanderthal brains

on average is actually higher
than the modern human average.

So this is maybe an indication
that they were not stupid.

They were actually
probably quite smart.

NARRATOR:
At the University of Tubingen,

Greek archaeologist
Katarina Harvati

studies Neanderthal fossils

for clues to their way of life
and their fate.

HARVATI:
The Neanderthal lineage
lived in Europe

for more than
half a million years.

Much were strongly built,
with quite wide trunks,

wide pelvis,
a lot of musculature.

And Neanderthals tend to have
the body shape

that is thought to be
cold adapted.

Now modern humans coming in,
early modern humans coming in,

they are looking very much more
African, or warm adapted,

in fact,
in their body proportions

and facial characteristics
and so on.

And did not have
any of these skeletal

or biological adaptations
to the cold.

NARRATOR:
Neanderthals were also
lighter skinned than humans

coming out of Africa because of
the latitude they evolved in.

In northern latitudes there's
less sunlight hitting our skin.

Iturns out, you have to have
allow a certain amount

of sunlight through to the
deeper layers of your skin

to synthesize vitamin D.

So people like me are mutants.

We have light skin because
we lived in northern latitudes,

we adapted to the environment.

Neanderthals, without question,

knew their environment
very well.

They were expert hunters.

But I don't think any
modern human had any illusions

about the strength
of the Neanderthals.

They knew that
if they were attacked,

they were probably goners.

But humans arrived in Europe
with superior weaponry

like bows and arrows,
and spears they could throw,

while the Neanderthals had only
developed thrusting spears.

HARVATI:
Modern people rely very much
on long distance weaponry.

Neanderthals didn't have
this sort of weaponry.

They really had to be extremely
fit and extremely strong

in order to be able
to just pull it off.

NARRATOR:
It is tempting to assume humans
used their superior weaponry

to kill off the Neanderthals.

But recent genetic findings
indicate the two groups

were closer than once thought.

STRINGER:
We know that many people today
have around a 2% input

of Neanderthal DNA
outside of Africa.

So clearly these populations
not only met and had offspring,

but that DNA came through
to the present day.

NARRATOR:
But does the fact that they
interbred tell us something

significant about relations
between the two groups?

Were they hostile or not?

HARVATI:
I think it's likely

that it wouldn't
always happen nice.

Just like with modern human
groups meeting each other.

Sometimes it's nice,
but more often it's not,

it's not peaceful.

And it involves
different degrees of violence,

different degrees
of assimilation,

different degrees
of cooperation,

and different degrees
of just avoiding each other.

NARRATOR:
But if we didn't kill them off,
why did Neanderthals go extinct

while our Homo sapiens ancestors
survived?

And can modern archaeology shed
light on this enduring mystery?

There are mountain caves
in southern Germany

that were once occupied
by Neanderthals,

abandoned and then re-occupied
by Homo sapiens,

creating a kind of
lab experiment

for archaeologist Nick Conard
to compare the two cultures.

He's been unearthing artifacts
from each occupation

and gives Niobe an insight
into his discoveries

and how he's interpreting
those finds.

CONARD:
The last Neanderthal occupation
is about here.

Starting here
we have modern humans.

And what's interesting
is when we look

at the material culture that
the modern humans made,

and compare it
to the material culture

that Neanderthals made,

the difference is
like day and night.

We find essentially
no symbolic artifacts

with the Neanderthals,

and we find the whole spectrum
of every imaginable

kind of symbolic artifacts
as soon as we get

to the period
with modern humans.

NARRATOR:
These are the symbolic artifacts
Conard's team has been finding:

carved figurines--

many out of mammoth tusk ivory.

These are among the oldest
figurative art ever discovered,

and reveal important qualities
of the people who made them.

CONARD:
They clearly have to do
with ideology,

perhaps religious beliefs
of these people.

And there's no question

humans are here doing things

that modern humans and no other
people had done before.

NARRATOR:
Among the figurines,
Conard's team found

some of the earliest musical
instruments ever discovered.

When can we prove
that people made music?

It's here and it's again
in this exact period,

slightly in excess
of 40,000 years ago.

This is a flute one.

So the wing of a swan.

You can make one of these
in an hour.

It's not a problem
to make it,

if you have good
stone tools.

The key thing
is the musical engineering

to know the exact dimensions

and exactly how
to carve the holes.

This one was
a gigantic surprise

for all of us.

NARRATOR:
It's an ivory flute,

and because it's hard
and brittle,

it would take far greater skill
than making a wooden one.

Who would make a flute
out of ivory?

So this one can be done
in one hour,

this takes about a hundred,
if you know what you're doing.

And these are functional flutes.

These are actual instruments
that we know can play notes?

Oh definitely, definitely.

You can play absolutely
beautiful music on them.

♪ ♪

Was music, in your view,
an important part

of keeping a society together?

Oh, absolutely.

I think all of these
symbolic artifacts

were the glue
that held society together.

CONARD:
The likelihood that music
is played in the caves is 100%.

The likelihood
that stories were told,

that ideas were exchanged,

that social interaction
was taking place here,

in my opinion,
is essentially certain.

NARRATOR:
To the humans who settled
in Europe,

music and art became
the building blocks

of a shared culture the
Neanderthals may have lacked.

FAGAN:
What humans brought with them
was imagination.

What they brought with them
were views of the landscape,

of trees, of animals,
which were alive.

We're the wise people.

That's why we're called
Homo sapiens.

Sapiens means "wise."

We plan, we think,
we imagine, we innovate,

and have an ability
to communicate

that was unimaginable
to the Neanderthals.

NARRATOR:
Just how much different
Neanderthals were

from Homo sapiens
remains controversial.

But both species
would be put to the test

by the onset of sudden periods
of intense cold,

signs that a new ice age
was coming.

These events were often
very rapid.

We know from climate records
that some of them happened

in less than ten years.

So the human populations
in western Europe

would have seen
this incredible chaos,

everything they were
familiar with

just disappearing--

all the plants,
all the animals--

within a few years.

NARRATOR:
Neanderthals were
cold weather people

used to icy conditions,

and as a species had survived
twice as long as Homo sapiens.

But at the end
of this deepest of freezes,

it was Neanderthals,
not Homo sapiens,

that stood on the brink
of extinction.

On Siberia's northern frontier,

Niobe has come to this frigid
and desolate spot

to meet another unique group
of hunter-gatherers.

But to find these arctic nomads,

he's had to hitch a ride
on a vintage Russian army tank.

This relic of the Cold War
is one of the few vehicles

capable of plowing
through snow and ice

to reach one of the world's
most unique cultures:

the Chukchi reindeer herders.

The Chukchi live seasonally,

part of the year
in settled villages

and the other
in the cold, open plain

with their reindeer.

Niobe has visited
the Chukchi before

and speaks to them in Russian.

(speaking Russian)

NARRATOR:
As he did with the San Bushmen,
he will stay with them

to observe their
survival skills.

(speaking Russian)

NARRATOR:
The Chukchi have been herders
for centuries,

moving seasonally
with the reindeer

that are their prime source
of food and clothing.

Niobe believes
their lifestyle and skills

are a reflection of a time

when our ancestors somehow
survived a global ice age.

It is immediately evident
they are right at home

in a land frozen solid
for nine months of the year.

In part, it's because
they've been raised here.

They have known
no other environment.

But they have also developed
superb cold-adaptive clothing

and live in small,
heat-saving shelters,

both made from animal skins.

(bleating)

(bleating)

NARRATOR:
Temperatures here can drop
below -40 degrees,

but it's warm and cozy
inside the tents,

where everyone gathers
around the fire

for food and warmth.

(speaking Russian)

NARRATOR:
Niobe is one
of the few westerners

to have spent time
with the Chukchi.

Another is Cambridge
anthropologist Piers Vitebsky,

who lived
with the Siberian nomads

and explains their ruggedness
in simple terms.

How can you put it
into words for me?

I suppose the key is

you don't have to see the cold
as an obstruction or an enemy.

Cold actually makes
the landscape easier to handle.

You can travel
immense distances.

On a sledge in winter,

you can travel hundreds of miles
in just a few days.

Then there's the food.

When you kill animals,

the land because a gigantic
open-air deep freeze.

That means you can arrange
to ambush, for example,

a herd of wandering
reindeer, caribou,

slaughter them
at far greater scale

than you could in the summer,

and you just pile them up
and use them.

NARRATOR:
A herder's life is unrelenting.

But Niobe observes that

it's women's work
that keeps the community warm.

(speaking Russian)

(speaking Russian)

NARRATOR:
Paulina is making
a pair of reindeer fur pants

for her husband Sasha.

To live in the far north,

it takes a mastery
of fur clothing,

and these women have it.

It's understanding how that fur
changes through the year

and then wearing the appropriate
hide at the appropriate time

that is the genius
of this technology.

THOMPSON:
Most of us see
an arctic environment

as utterly hostile

and as very dangerous
to survival.

I think the key trick is
to imitate the animals,

because we are
a hairless animal,

and all the other animals
around us in the cold

are very hairy.

What you have to do is
you have to take their fur

and put it all over
your own body.

There are boots in Siberia
that are made

directly from the shin fur
of reindeer.

So there's an inner boot,
and that's short fur

because it's taken
from a reindeer killed in July.

Summer fur.

In summer, so their fur
is the least

because they're actually trying
to lose heat all the time

because they hate heat.

That's what the antlers
are doing, too.

They're kind of a radiator.

THOMPSON:
Yeah, yeah.

And then over that,
you have an outer boot

which is made from fur
killed in November,

when it's at its thickest.

And even your sleeping bag
is made the same way.

(dog barking)

NARRATOR:
It's hard to believe
anything grows here

that the reindeer can eat.

But there are small bits
of edible plants

under this snow.

And these get exhausted
pretty quickly.

When they do,

it's time to pack up
and find better grazing land

or return to their villages
until the snow clears.

For the reindeer
and their keepers,

this cycle of seasonal migration
makes life possible.

The Chukchi offer Niobe and us
a glimpse

at our ancestors' ability
to adapt, innovate,

and rely on each other

even in the most challenging
of environments.

Could these traits
have given Ice Age humans

a survivability edge
over the Neanderthals?

HARVATI:
When the times are rough,

social networks suddenly become
extremely important.

It's very important if you can
go to the next group over

and somehow be connected to them

and somehow be taken in
or helped out.

NARRATOR:
Homo sapiens may have had
another advantage.

Like the Chukchi,

they carefully crafted
cold-weather clothing.

FAGAN:
Clothing was one of the most
important innovations

brought into Europe
by modern humans.

But that was made possible

by one of the most important
artifacts ever invented:

the eyed needle,
made of antler or ivory,

which enabled people
to sew clothing

and fit it to people.

NARRATOR:
But perhaps the simplest
explanation

for our ancestors' survivability
may be their greater numbers.

HARVATI:
Modern humans can reproduce
extremely fast.

The result of that is that
human population expansion

is very quick.

What we know
about Neanderthals is

not only are they living
in small groups,

but the overall population

seems to have been
extremely small.

NARRATOR:
By 40,000 years ago,

the Neanderthals, Denisovans,
and all other archaic species

were, for the most part, gone.

JOHANSON:
There were four or five species
wherever we went,

but we were the survivors
because we brought with us

very sophisticated ways
of looking at the world:

division of labor,

very extensive tool kits
for hunting and gathering,

and gradually, I think...

I don't think
it was a holocaust.

I think that
in terms of a model,

I see us displacing people.

NARRATOR:
By 25,000 years ago,
we had reached all the lands

between the Atlantic
and the Pacific,

including the Arctic...

...and were poised on the cusp
of a vast new territory.

By now, the last great ice age
had reached its peak

and the world became
even colder.

As the seas froze
and the ocean levels dropped,

a new land appeared

in the waters
of the Bering straits

that would eventually connect
North America and Asia.

This land called Beringia

would last
at least 10,000 years,

and for long stretches

may have looked like
the cold, rocky landscape

of today's far eastern Siberia.

Here, another arctic people,
the Yupik,

live off the land--
or, in this case, the sea.

And they travel over
and through the icy waters

in another echo from the past:
the skin boat umiak.

When the sea freezes solid,

people can walk or sled
across the ice.

But when the ice breaks up,

the umiak is light enough
to carry

and sturdy enough to row--
a perfect Beringian vessel.

Making one is a fairly quick
operation,

and Niobe joins in.

Up here in the Arctic,
every resource is precious,

so all the wood in this frame

has probably had
several lives already.

This could have been
a door frame once.

Now it's about to go out
to sea.

When the boat's frame is ready,

it's covered
with a single walrus skin

shaved so thin,
it's almost transparent.

What's remarkable
about this kind of boat

is that every part of it
can be found

in a completely treeless
landscape:

skin, driftwood, and bone.

Many experts believe

the first people
to enter North America

did so by working their way
along the Bering land bridge

in skin boats just like this.

They may have even trekked
at least part of the way across

when ice didn't block
their progress.

Regardless,
by 15,000 to 20,000 years ago,

our ancestors set foot
upon a land

no one but animals
had entered before.

Although archaeological
and other evidence

pointed to America's
first people

crossing the Bering straits
from Asia,

discoveries of ancient artifacts
that appeared European in origin

led to a counter-theory:
that the first Americans

actually crossed the Atlantic,
not the Pacific.

And beyond the scientific
findings,

many Native Americans believe

they are neither Asian
nor European...

That their people
have always been here.

In 1968, a chance discovery

in the hills
near Bozeman, Montana,

would begin a 45-year saga
that finally unmasked

the origins
of America's first people.

Sarah Anzick was just
two years old

when that discovery occurred
on her family's land.

ANZICK:
What I've been told is that
these construction workers

who had received permission
from my father

to extract land fill
for a local high school project

were actually
just digging the dirt out,

and one of the construction
workers noticed

one of these giant artifacts

that had come tumbling out
from the site.

NARRATOR:
To their amazement,
they would unearth

over 100 stone
and bone artifacts,

all about 13,000 years old.

Shane Doyle
is a Crow Indian historian

who has studied these artifacts

identified as belonging
to Clovis people.

DOYLE:
The Clovis culture

had a very distinctive style
of fluting that they used

to make their spear points
and their arrowheads.

So you can see how it's been
fluted down the middle here

and would actually be attached
to a larger wooden spear point.

These were all the tools
that they needed

to get by on a daily basis
by hunting and gathering.

They were hunting everything
from wooly mammoths to bison,

and so they needed these.

These were their most
precious commodities

as far as survival goes.

NARRATOR:
But why did they bury such
valuable and important items?

The answer soon became clear.

As the men dug
below the artifacts,

they were stopped
in their tracks

by a young boy's skeleton
covered in red ochre.

They had chanced
upon a burial site

of one of the oldest
human skeletons

ever discovered
in North America.

As a child, Sarah Anzick
was hardly aware

of the discovery's significance.

But she became
a molecular biologist,

and in the 1990s was working
on the Human Genome Project

when she realized an opportunity

to discover the true origins
of Native Americans

might lie with DNA from
the Clovis child's skeleton,

now carefully stored away.

ANZICK:
And I started thinking about,
"Well, you know,

we have an ancient remains
that's 13,000 years old,"

and so I kind of began
to put two and two together,

thinking, "Wow, you know,
wouldn't it be really neat

"if we could take a glimpse
into the ancient past

through the genome sequence
of this ancient individual?"

NARRATOR:
Sarah decided to contact
local Montana tribes

to see if they
would have objections

similar to those voiced
by Native Americans

when scientists tried to recover
DNA from the Kennewick Man.

The discovery
of a 9,000-year-old skeleton

in Kennewick, Washington

had triggered a contentious
legal battle.

Native Americans said
the bones were sacred

and should be reburied,

while scientists
wanted the knowledge

their DNA could provide.

The battle was ongoing

when Sarah approached
the Montana tribes

asking to do DNA studies
of the Clovis child.

One of the tribes
was quite supportive

and interested in my findings,

and the second tribe
on the other hand were not.

NARRATOR:
Sarah decided
to go forward anyway.

But she had never worked
with ancient DNA,

a far more difficult process
than sequencing fresh DNA.

So on her own time
at a private lab,

she began practicing
on old animal bones

and failed.

ANZICK:
And so at that point,
given the challenges

and the obstacles

and the heated debate
with the Kennewick man,

I just put everything aside
and took a rest.

NARRATOR:
The hiatus would last ten years.

But in 2009 over in Copenhagen,

DNA hunter Eske Willerslev,
who had been so sappointed

with the Skhul Cave
tooth results,

was asked by Sarah
to lead a new effort

to recover the genome

of what was now being called
the Anzick child.

The Copenhagen team, with Sarah
joining in, went to work.

Unlike the much older
Skhul sample,

they were able to get
strong DNA signals right away.

They focused on recovering DNA
from regions called haplogroups:

strands of DNA sharing
common mutation patterns

that go deep into the past.

They then compared
Anzick's distinctive patterns

to the genomes
of nearly 150 modern populations

around the world...

...and to a few
ancient population samples

previously decoded.

It took the team four years,

but they finally narrowed down
exactly where the genes

of the Anzick child
had come from.

These findings were really
significant.

For one, that they refuted
the Solutrean hypothesis

where the first Americans
came across the Atlantic

and they're European in descent.

They're not.

NARRATOR:
As expected, major elements
of the Anzick child's genome

came from across the Pacific.

One-third of the boy's genome
matched genes

from a 24,000-year-old
Siberian skeleton,

so he's part ancient Siberian.

His other genes matched those
of ancient East Asians,

so two-thirds of his genome
comes from them.

But this specific
genetic combination

can no longer be found

in any living populations
west of Bering Strait;

only in living Native Americans
east of the Strait.

So what does this mean?

WILLERSLEV:
So basically,
you can almost imagine,

you know, these two
very distinct groups of people

meeting each other,

interacting, and you can say
the child of those,

if you want, is actually,

genetically speaking,
Native Americans, right?

And then the question was,
when is this happening?

Where is it happening?

ANZICK:
What we believe is that
there was a cross

between eastern Asians
and Siberian

up in the Bering strait,

and they crossed
over the Bering strait

and populated the Americas.

NARRATOR:
So from the edge
of the Asian continent

or from the now vanished land
of Beringia,

the ancestors
of the Anzick child

came to North America

bearing a genetic signature
found nowhere else in the world,

and would pass it to generations
of Native Americans to come.

That would fit with the idea
that you see Native Americans

as being something genetically
completely unique.

NARRATOR:
Back in Montana,
Sarah and Eske were nervous

about releasing
the study's results,

wondering what Native American
reactions would be.

ANZICK:
We didn't want to publish

without some communication
to the local tribes

to tell them of our findings

because we didn't want them
hearing about this

for the first time
through a publication.

NARRATOR:
They invited Crow historian
Shane Doyle

to the discovery site

to assess his reaction
to the study and their findings.

It feels really good.

WILLERSLEV:
We met him at the Anzick site,
and he knew nothing about this,

what we had found,

and he became
extremely emotional.

(chanting)

WILLERSLEV:
And he took out this drum
and he start playing a song.

(chanting)

WILLERSLEV:
I was really overwhelmed
with emotion.

DOYLE:
The results show that American
Indians are from America.

We don't come
from anyplace else.

Nowhere else in the world
is there Native American DNA

except for the Americas.

NARRATOR:
But Shane told them

the tribes would now want
the child reburied.

DOYLE:
We understand that
the study's been made

and we can't go back
in time now,

and so I think
you should put the boy back.

He's given us
all this information,

and now it's time
to return the favor

and put him back
where his parents left him,

where his grandparents
shed tears for him,

and it's just
the right thing to do.

(chanting)

NARRATOR:
On a rainy fall day,

representatives
of various local tribes

joined in the solemn ceremony
to return this special child,

their most ancient relative,
to his original resting place.

(chanting)

Initially, Sarah and Eske had
misgivings about Shane's request

to rebury remains that would be
lost to science forever.

ANZICK:
I had a huge conflict.

I had a scientific community

who was telling me
how important this was,

and then I also had
the Native American communities

who were also very passionate

about seeing this child go back
to his resting place.

NARRATOR:
It had been a long and emotional
struggle for Sarah Anzick,

but in the end, she did
what she always knew she would.

ANZICK:
From the first day that
I set eyes on these remains,

I always felt like it had
a story to tell, you know?

And I just felt like
it was important

that this child had the chance
to tell his story.

NARRATOR:
And as it turns out,
the child called Anzick

is far more significant than
anyone could have imagined.

Close to 80% of all living
Native Americans

carry his genome,

and that percentage
is even higher

in Central and South America.

This means the descendants

of a single band
of Ice Age hunter-gatherers

who crossed the Bering straits
around 15,000 years ago

would eventually create

virtually all
the great civilizations

of North and South America

that flowered
long before European contact.

By 5,000 years ago,
there was just one frontier

left for humans to conquer:
the mighty Pacific.

Almost 10,000 miles wide,
the Pacific Ocean covers

about a third
of the Earth's surface.

Its islands are like
grains of sand

scattered across
a vast blue void.

Yet somehow, early humans
managed to reach them all.

LISA MATISOO-SMITH:
These are distances
that are greater than

the distance across Europe.

The whole settlement
of the Pacific

really is something that's
under-celebrated and undervalued

in terms of representing

the capabilities of these people
thousands of years ago.

They did an amazing thing.

NARRATOR:
In the 18th century,

when England's Captain Cook
arrived in the Hawaiian Islands,

he found people
he called Polynesians

had been there long before him.

How was this possible?

Cook needed navigational charts
and full-masted ships

to reach the middle
of the Pacific,

while Polynesians had
less sophisticated-looking boats

and sailed with no charts.

So how did they reach
specks of land

in the middle
of a 10,000-mile-wide ocean?

Some experts believed the first
people to reach Pacific islands

drifted on crude boats
pushed by trade winds

that blew west
from South America.

This theory of accidental drift
originated with Thor Heyerdahl,

a visionary Norwegian explorer.

In 1947, Heyerdahl
and a small crew

set off from Peru
to prove his theory.

The men built a balsawood craft
called Kon-Tiki

and just drifted westward
on the currents.

After 101 days,
they crashed into a reef

off a tiny island
in the South Pacific.

Luckily, no one drowned.

It was an extraordinary
adventure

that embedded
in the public imagination

the idea that humans from South
America settled the Pacific.

But was Heyerdahl correct?

Anxious to learn more
about the famed explorer,

Niobe traveled to Oslo
to meet Heyerdahl's son.

Well, the funny thing
with my father was that...

I'm myself a traditional
academic.

I'm trained to collect

samples, data,

analyze it, and draw conclusions
from what I have found.

My father, he jumped
to the conclusion first.

He was in many ways also
an artist with an imagination.

He srted with the conclusion
and worked his way backwards,

like a lawyer
defending his suspect.

SCHIEFENHOVEL:
To Heyerdahl,
his main idea was

those people came
from South America,

the Polynesians and those guys,

because they were sitting
in the wind in their boats

and the wind would blow them
to the northwest.

A completely anthropocentric
European idea.

NARRATOR:
And wrong as well.

Recent genetic studies
of Pacific Islanders

reveal their origins
are not in the Americas,

but in Asia.

PATRICK KIRCH:
If we look at the Polynesians

and their other
close relatives

in Micronesia
and parts of Eastern Melanesia,

they share many
of these genetic traits

all the way back to Taiwan.

So a lot of the genetic evidence

that's emerged
in the last two decades

has helped to reinforce
the picture that archaeology

and linguistics have been
giving us for quite a while.

NARRATOR:
That archaeological evidence

reveals human populations
migrated into Southeast Asia,

and by at least 40,000 years ago

had managed to reach
island groups

such as Indonesia
and the Philippines

perhaps when sea levels
were lower,

narrowing the channels.

THOMPSON:
For early humans
crossing the Asian continent,

this should have been
the end of the line:

southeast Asia,

on the edge of the mighty
Pacific Ocean,

an impassable barrier

to the further colonization
of the planet.

Except it wasn't really
a barrier.

Just like for these
Philippine Islanders today,

our ancestors found ways
to live with the sea,

and soon
they were crossing it.

NARRATOR:
The wonder is that Heyerdahl
and other experts

could not see the obvious.

There are perhaps
no other cultures

as comfortable
at living with the sea

as the inhabitants
of the Pacific Islands.

That they, and not people
from South America,

would conquer the Pacific
now seems obvious.

But how exactly did they do it?

The first thing they needed was
the right kind of boat.

There is no archaeological
evidence of the earliest boats,

but there is one place
that might offer a clue:

Papua New Guinea, the world's
largest tropical island,

which lies just west
of Indonesia.

The immense Sepik River
drains a tropical wilderness.

Here, humans live in a labyrinth
of streams and swamps,

and they travel throughout
in dugout canoes,

a vessel that probably
has been in use

for tens of thousand of years.

And these men
are still making them

as their ancestors did
many centuries ago.

THOMPSON:
How long does it take

to adze out
a canoe like this?

It takes one week.

Who's the carpenter
of this boat?

It's my older brother.

(laughing)

NARRATOR:
The craftsmanship of the
canoe-makers is extraordinary.

Over time,

Papuans took the dugout
to astonishing extremes...

By making war canoes
that were long and fast.

SCHIEFENHOVEL:
The Papuans have
very long dugouts,

and that is a very clever idea

because every sailor knows
the longer your boat,

the faster you travel.

The Papuan peoples,
as far as I know,

never had any sailing boats

because they did not venture
into the sea.

Those canoes would capsize.

NARRATOR:
Canoes are best in calm waters,
not in ocean waves,

so island people added
an outrigger.

The outer rig widens
and stabilizes

the boat's thin hull

so waves hitting the boat
from the side

can't easily tip it over.

And with a sail
to catch the wind,

these boats could move
easily and swiftly

between closer islands.

And as it turns out,

they could indeed sail
into the wind,

putting to rest Heyerdahl's idea

that they could only drift
with the wind.

Wind tunnel tests on a model
of an ancient Polynesian vessel

clearly demonstrate
they could tack,

which is how sailboats
sail into the wind.

As sailors head into the wind,
they steer the boat

from one diagonal direction
to the opposite diagonal.

Crossing the sails over

allows the wind to push the boat
forward on a zigzag path,

something every
modern sailor knows.

So island-hopping by outriggers
throughout the southern Pacific

settled this region
fairly quickly.

But it's many miles
of open ocean

to mid-Pacific islands
like Hawaii,

a perilous trip
for a small outrigger.

Somebody probably around 2,000,
2,500 years ago

gets the idea, "A-ha!

"I get rid of the outrigger,
I bring another canoe hull in,

I put them together,
and I got a catamaran"--

basically
a double-hulled canoe,

and that was then
the platform that allowed

an even greater phase
of expansion.

NARRATOR:
A catamaran is still one

of the bt sailing vessels
in the world,

swift and stable

with enough deck space
for crew and supplies.

This double-hulled replica
of an early Polynesian catamaran

called the Hokule'a

is certainly sturdy enough
for long ocean voyages.

But how did early Polynesians

navigate their immense
watery domain?

Kalepa Babayan is one
of the ship's senior navigators.

He sails the Pacific
without charts, GPS,

or instrumentation of any kind,
just as his ancestors once did.

He learned this
extraordinary skill

from the last
traditional navigator,

a legendary sailor
named Mau Piailug.

Now deceased, Mau was living
on a remote island in Micronesia

when director Sam Low
captured him on film.

LOW:
Mau Piailug was one of a handful

of navigators
who still practiced

the ancient art
of non-instrument navigation,

the ability to use the rising
and setting points of stars,

being able to find your way

across thousands of miles
of ocean

with no instruments, no charts,
with no assistance at all

from anything other than
what he had memorized.

NARRATOR:
This footage shows Mau
teaching these young men

how to navigate
by the night sky.

These lumps of coral represent

the rising and setting points
of highly visible stars.

NARRATOR:
The star called Mailap,
the big bird,

is the first to rise in the east

and the first to set
in the west,

defining two compass points.

Since the axis of the earth
always points north

toward the North Star,

by memorizing the position

of the other rising
and setting stars,

the navigators always know
where they are.

On cloudy nights or in daylight,

Mau teaches the young men
to read swells and currents

to keep the boat
on the desired path.

These are timeless
navigational skills

that enabled their ancestors
to master the mighty Pacific.

LOW:
To set out in a canoe
1,000 years ago

would have taken an almost
superhuman race of people

to be able to endure
that kind of voyage.

The ocean was always their road.

Going to sea for sea people

is one of the most natural
things you can do.

NARRATOR:
With astonishing
navigational expertise,

Pacific islanders moved swiftly
and systematically

across the ocean.

From islands east of Indonesia
beginning about 3,000 years ago,

they moved east, south,
and north,

settling one island
after another,

finally reaching Hawaii
probably around 1,200 A.D.

To Lisa Matisoo-Smith, this is
nothing less than extraordinary.

MATISOO-SMITH:
What it tells us,

this instantaneous
kind of dispersal

and continuous
successful settlement

from that point onwards,

is that these people knew
what they were doing.

These people were prepared,
they know where they're going,

and they know what they need
to survive when they get there.

They did an amazing thing
in being able to navigate,

and I think we're beginning
to value that

and recognize that skill.

NARRATOR:
Probably the last
Pacific island to be settled

was Easter Island.

Over a thousand miles
from the nearest land,

it was once thought to be as far
as the Polynesians could sail.

THOMPSON:
The Polynesians who settled here

had sailed to the most isolated
inhabitable speck of land

on the planet.

And then the transformed
this volcanic rock of an island

into a landscape
full of their ancestors.

NARRATOR:
According to island traditions,

these iconic stone figures
called moai

are revered images
of their ancestors

charged with sacred power.

At the height
of the statue-building cult,

several thousand people lived
on the small island.

Although it's a whopping
2,500 miles

from Easter Island
to South America,

could Polynesian sailors have
launched a journey from here

and reached the Americas?

The possibility
that Pacific islanders did

rests on two pieces of evidence.

First, the ordinary
sweet potato.

KIRCH:
And the sweet potato,

there's no doubt it's a plant

that was domesticated in Peru
in South America,

but it was in Polynesia
when Europeans arrived.

We know that it was
in East Polynesia.

We have archaeological
charred remains

that are dated to
about a thousand years ago.

NARRATOR:
So how did this plant
that evolved in South America

end up on Pacific islands
thousands of miles away?

Somebody got to South America

and brought
this sweet potato back.

NARRATOR:
That the people who brought it
back to the islands

were Polynesians

rests on a second piece
of evidence

recently uncovered in Chile.

Here, Dr. Jose Ramirez-Aliaga

is about to show Niobe
that discovery,

which may prove once and for all
that Polynesians

did reach South America
long before the Spanish.

RAMIREZ-ALIAGA:
I want you to see

this fantastic material
I found here in the basement.

NARRATOR:
He follows Dr. Ramirez-Aliaga
to a storage room,

where he's shown a box
of ancient skulls.

Did you know
this was here?

I didn't know
until a month ago.

So it was
rediscovered.

Exactly.

NARRATOR:
The skulls date from

about 1000 to 1300 A.D.

They were discovered
a century ago

on an island off Chile's coast,

but were stored away
until Ramirez-Aliaga found them.

He believes the skulls
are Polynesian

because of their unique shape.

I'll follow you.

All right, follow me.

What tells you that this is
a Polynesian skull, possibly?

At that time, the evidence was
the pentagonal shape,

the roof shape
in the top of this cranium.

So a flatter top?

No, no, this kind of shape here
which makes vertical sides,

and this, like, roof,
double roof on top.

So it's
the pitched roof form.

Exactly.

Our skulls in South America,
the Mapuche,

is round,
completely round.

NARRATOR:
So not round
like a South American,

but pentagonal
like a Polynesian,

and someone who lived
a hard life.

RAMIREZ-ALIAGA:
This guy had terrible
diseases, actually

THOMPSON:
Where do you see
evidence of that?

RAMIREZ-ALIAGA:
These holes sometimes
are related to anemia.

THOMPSON:
Right, so some kind
of a dietary deficit.

RAMIREZ-ALIAGA:
Yeah, exactly.

Another trait
which is very interesting

is this muscle attachment.

It's very strong.

People who work
very hard

with their necks.

Ah, okay, so carrying things
with the neck.

I mean, not carrying,
pulling with the head.

Right, right.

Terrible!

So they have muscles
like a bull

from here
to the shoulders.

Right, right.

NARRATOR:
Although the Chilean skulls

do not definitively prove

Polynesians reached
South America,

coupled with the spread
of the sweet potato,

the evidence is mounting.

I have no doubt that Polynesians
made contact with the Americas,

and I think, you know, there's
strong evidence to support that.

NARRATOR:
If Matisoo-Smith is right,

long before the more celebrated
European voyages of discovery,

Polynesians
and other native people

had crossed the entire Pacific,
shore to shore,

and landed on its islands
as naturally as seabirds.

Back in Hawaii, Niobe wants
to meet Kalepa Baybayan,

navigator of the Hokole'a.

Hi!

Hey, welcome aboard.

Nice to meet you.

NARRATOR:
Kalepa was just a teenager

when he learned the art
of traditional navigation,

and now he is preparing himself
and his crew for a sea journey

far longer than any
of his ancestors undertook.

They will attempt
to circumnavigate the globe.

And for most
of this epic journey,

they will use only
the traditional techniques

of the master sailors
of the Pacific.

BABAYAN:
You have the external compass,

which is made up
of all the natural tools:

the stars rising,
stars setting, right?

The moon, the planets,

all rising
from the one horizon,

and then the wind
and the ocean swells.

The wind and the oceanic swells
all come from the same horizon.

They all come
from the east.

You've just got
to internalizehat rhythm

and understand what direction
they're coming from.

We're very competent
and very confident navigators.

We know the Pacific
real, real well.

We're not going to sail
off the edge of the earth, so...

That's good to know.

BABAYAN:
Navigation is 24 hours a day,
seven days a week.

From the time you take the ropes
or pull your anchor

to the time you arrive at land,
you're constantly navigating.

You only know where you are
by memorizing,

each and every second,
where the canoe has traveled.

So you've got to be able

to internalize the clock
of the universe.

(trumpeting)

NARRATOR:
On May 18, 2014,
under the Hawaiian flag,

Hokule'a embarked from Oahu

on its three-year
circumnavigation of the globe.

The journey will cover
47,000 nautical miles,

with stops at 85 ports
in 26 countries.

Kalepa's crew will live
on this open deck

for months at a time.

As they prepare the Hokule'a,

they are also preparing
themselves.

Of the Hokule'a and its crew,

this journey will demand
everything.

We are finally gaining
a more complete understanding

of the heroic scop
of our very own story.

MAN:
Yeah, but does that
fit with this?

NARRATOR:
Every chapter in that story
is being enhanced

by groundbreaking scientific
discoveries all over the world.

A new set of human remains,
for example,

has been recently unearthed
in the Rift Valley

that will for the first time
provide us

with a nearly full skeleton

of one of our
earliest ancestors.

ASFAW:
This is the ear hole.

This is the kneecap.

We found both of them.

This kind of discovery
from head to toe

is very rare.

Look at this: the elbow.

Big guy, very big guy.

NARRATOR:
And with more analysis
these bones could turn out to be

among the most important

Homo sapiens remains
ever found.

ASFAW:
For sure, these are the people
who about 100,000 years ago

left Africa
and populated the world.

NARRATOR:
From small groups
of hunter-gatherers

living a precarious existence
in Africa,

our ancestors would eventually
reach every place on earth.

An epic, often harrowing
journey;

an achievement almost impossible
to imagine.

WILLERSLEV:
We have always had this idea

that man back in time
were primitive.

What you really find out:

they were capable
of amazing things.

They are adventurous,
just as we are today.

Homo sapiens is a crazy animal.

They do things which you don't
believe are possible.

ASFAW:
We are all related

to this early Homo sapiens.

Those different types of people
that you see all over the world,

genetically,
we are almost identical.

NARRATOR:
And as a species, our fates
will be forever intertwined.

We evolved from someone
like Lucy, probably,

who was very closely tied
to the natural world,

to a species that
all of a sudden is

in charge of the earth,
of the globe.

NARRATOR:
Our powerful mind
got us this far,

but what lies ahead?

Are we clever enough
for the changes to come?

In evolutionary time,
we're young--

only about 200,000 years old.

Will we continue to evolve,

or will the Homo sapiens line
die out with us?

POTTS:
We're the first species
on the planet

that has ever been aware
of the possibility

of its own extinction.

MATISOO-SMITH:
We're not indestructible.

There are evolutionary
dead ends.

There are some species
that don't survive.

JOHANSON:
We are the single
most adaptable creature.

We can sit on top of a rocket
and shoot ourselves into space.

We are incredibly adaptable.

That is, hopefully,
our salvation.

NARRATOR:
Our salvation could be
in our very name:

Homo sapiens--
a human of the mind.