Original subtitles

ELLA AL-SHAMAHI: Where do we come from?

When did our story really begin?

Who were the first Homo sapiens?

Not just humans who looked like us,

but people who thought

and behaved as we do.

People we would recognize as truly one of us.

We Homo sapiens first appeared

over 300,000 years ago.

We're not the first species of human.

We're not the biggest, we're not the strongest.

We're just the latest in a long line of other humans.

Yet a few hundred thousand years later,

we are the only ones left.

How on Earth did this happen?

♪ ♪

I'm Ella Al-Shamahi,

a paleoanthropologist.

People spend their whole lives

trying to find a fossil as significant as this.

Our story is stranger and more dramatic

than most of us realize.

Thanks to groundbreaking fossil evidence,

and advances in DNA science,

we are able to picture the lives

of our ancestors as never before.

From our very earliest origins

to our migration to every corner of the globe.

From the first marks we made on cave walls

to the rise of cities.

These are the unlikely events that forged us.

Moments of chance,

but also ingenuity, of beauty and destruction.

This is us.

This is our story.

And it's what happened

in the 99% of our history

before the invention of writing,

when our story wasn't written in books,

but was written in our bones and DNA.

This is the story of what made us...

"Human."

"Origins."

Right now, on "NOVA."

♪ ♪

(birds chirping)

(giraffe bleating)

AL-SHAMAHI: We're used to living in a world filled with other species.

Over eight million share our planet with us.

But there is only one of us.

Only one human species, Homo sapiens.

And so, it's really easy to forget

that it wasn't always like this.

The world before us was alive with other human activity.

♪ ♪

When Homo sapiens first emerged,

there were at least six different human species.

And using the latest scientific data,

we can reconstruct what they might have looked like.

There were so many species of human.

You had Homo erectus, an ancestor of ours

and an incredibly successful

species because they lived for about two million years.

Now Homo erectus was actually the first in our genus

to leave Africa.

And we also think that they were the first to use fire.

There's also Homo neanderthalensis,

who you probably know as the Neanderthals.

Neanderthals lived in Europe all the way into Central Asia.

They were cold-adapted.

And they were expert hunters.

There was also Homo floresiensis,

who some people affectionately call "the Hobbit."

Because they were only about a meter tall,

so that's about three and a half feet.

Tiny, and yet adapted for living on an island.

It seems like a fantastical world.

And I can't help it; it reminds me of "Lord of the Rings."

Only instead of a world with elves and dwarfs,

you had a magical place with other humans.

♪ ♪

The human family tree had many branches.

But which branch did Homo sapiens first emerge from?

We don't know for sure,

but we're getting closer than ever to finding out.

♪ ♪

For the longest time,

we thought we knew the origins of our species.

We thought we began 200,000 years ago in East Africa.

♪ ♪

But new revelations from out here in Morocco,

from a part of Africa that people

weren't really considering, are forcing us to rethink

our very first steps on this planet.

In a remote cave in North West Africa,

a chance discovery

uncovered some mysterious human remains.

Someone was living here.

Thousands of years earlier than we imagined.

(speaking Arabic):

ABDELOUAHED BEN-NCER (speaking Arabic):

AL-SHAMAHI:

BEN-NCER:

AL-SHAMAHI: This is Jebel Irhoud 1, and it was a complete mystery,

because some of its features are very much like us,

very Homo sapiens and others are much older, much more primitive.

So, if you look at this individual's face.

Its face looks a lot like ours.

The Homo sapiens face is incredibly gracile.

We have incredibly delicate features.

They kind of tuck in under our braincase.

If you imagine a prehistoric human,

you kind of always imagine a much kind of more prognathic,

we say, much more kind of jutting forwards face.

This individual's face is much more tucked under,

it's much shorter.

But there are some features that aren't us.

Notice this brow ridge up here, this supraorbital structure.

Now look at me.

You don't get modern humans walking around today

with these massive things on top of their eyes.

Now the brain case is not us.

Can you see how round my brain case is, it's globular.

Whereas this is almost stretched out,

so it almost looks like somebody has got my braincase,

but kind of stretched the back of it out.

It's almost like...

...straight on the face is Homo sapiens,

but from the other angles, it's not us.

♪ ♪

This skull was an enigma.

An anomaly that didn't fit neatly

into the human family tree we thought we knew.

It looked partly like Homo sapiens.

And partly like an earlier kind of human.

So, the question was, was this a different species,

or could it be an early version of us?

(tools clanking, dirt brushing)

Several decades after

the initial discoveries came a breakthrough.

Archaeologists uncovered another 16 fossils.

All with the same blend of features.

And taken together with the old finds,

a fuller picture started to emerge.

BEN-NCER:

AL-SHAMAHI (speaking Arabic):

BEN-NCER:

AL-SHAMAHI:

BEN-NCER:

AL-SHAMAHI:

BEN-NCER:

AL-SHAMAHI: With each new find the evidence grew.

These were not some other species.

But Homo sapiens, with hints of an earlier ancestor.

But it wasn't until archaeologists

were able to more accurately date the remains,

that the final piece of the puzzle fell into place.

The archaeologists, using new and improved

dating techniques, were able

to give us dates for these fossils.

And they tell us that these individuals

lived about 300,000 years ago.

And that is mind-boggling because

we thought our species was only about 200,000 years old.

What these fossils tell us

is that our species,

Homo sapiens, is 100,000 years older than we thought.

We are much older than we realized.

This fossil went from being enigmatic

and a, basically a mystery,

to being one of the most important fossils

in our whole field.

♪ ♪

Thousands of miles from East Africa

where many anthropologists thought we began,

and far older than expected,

these are the earliest Homo sapiens ever found.

And they have forced us to re-think

other finds across Africa.

Which are painting an entirely new picture

of our origins, suggesting Jebel Irhoud...

...was just one of many emerging Homo sapiens populations.

It's... (exhales) it's a bit like having a peek

behind the curtain of evolution.

This is a stage in the journey to becoming us.

I wonder what it would feel like to come face to face

with one of the people from Jebel Irhoud.

(wind blowing)

If we were to look into their eyes...

...into those quite delicate features...

...would we see ourselves within them?

The answer is they were not modern humans like us, not yet.

(fire crackling)

They were an earlier stage in our evolutionary journey,

bridging the gap between us

and our more ancient human ancestors.

Our emergence was actually slow, and honestly, at the beginning

we were just not that special.

Now, early iterations of Homo sapiens

like Jebel Irhoud were popping up all over Africa.

Many anthropologists once believed in a single origin,

a sole cradle of humanity in East Africa,

but our story is far richer

and more interesting.

The latest evidence suggests the traits that make us

who we are today,

emerged in different places,

across thousands of miles,

and over hundreds of thousands of years.

Appearing bit by bit.

Like sparks igniting across the African continent.

♪ ♪

(thunder rumbling)

And yet,

Homo sapiens could have easily vanished without trace.

(lightning striking, thunder rumbling)

Because just as we were finding our place in the world...

...something threatened to wipe us out altogether.

It's in East Africa's Great Rift Valley

that we can trace the next chapter of our story.

This dynamic landscape

holds some of the clearest evidence

of the forces that set

our species on a radically new path.

When they say the Great Rift Valley

of East Africa is a dramatic place...

they're not kidding.

I mean, look at it.

I can literally hear it bubbling behind me

and it's the result of a geological process

that sees three tectonic plates tearing

away from each other,

which results in a dynamic landscape.

And even though

this part doesn't look that hospitable,

it has been a home to people

for a very long time.

In fact, the conditions here

for fossil preservation are so good,

we know that is has been a home

to people for millions of years because of the wealth

of archaeological evidence found here.

This is one of the most fossil rich regions in Africa.

Its unusual geology has preserved human remains,

but it also offers

a glimpse into the forces we think drove our evolution.

So, within the lake beds

here, if you dig deep,

you can actually extract sediment cores.

Now one here in Ethiopia was about 280 meters deep.

So that represents over 600,000 years.

And within that sediment,

it's a bit like a time machine because

bits of ancient environment are trapped.

By analyzing these sediment layers...

...scientists have uncovered a window...

...into the world some of the earliest Homo sapiens

were living in.

(thunder rumbling)

Over tens of thousands of years,

wild climate swings engulfed Africa.

(splashing footsteps)

Thrusting the different fledgling

populations of Homo sapiens...

(thunder rumbling, lightning striking)

...into a landscape of extreme

and unpredictable change.

♪ ♪

(waves crashing)

Ecosystems were transformed.

Rivers and lakes swelled.

Cutting people off.

Elsewhere, grasslands turned to desert.

Creating a struggle for survival.

That could have wiped Homo sapiens out altogether.

(baby crying)

But it didn't, it had the opposite effect.

It helped drive us forward.

Under pressure,

isolated Homo sapiens populations both learnt

new skills and genetically adapted

to the challenging conditions.

People with minds able to innovate

had a better chance of staying alive.

Then, as their climate continued to change,

the surviving groups

came back together,

they shared skills, and crucially,

interbred.

Passing their unique genes onto their children.

(water trickling)

It was a process

that began to change our ancestors permanently.

The people who survived emerged stronger than ever.

(animal bleating)

Today, most of us live in towns and cities.

And so, the reality of being affected by the climate

as a result of being a nomadic person kind of

escapes us, but you've actually got

a really good example

here with the Afar people.

They are nomadic and so they get

pushed and pulled around the landscape.

And it would have been very similar with our ancestors,

but actually, in a more extreme fashion.

These different groups,

as they were moving around, would have at times met

and when they did, they would have, of course,

shared skills and knowledge and DNA.

It was this mixing of groups that ultimately brought

us closer to becoming the Homo sapiens

we are today.

There's this new exciting theory

that suggests that our origins as a species are so much more

complicated and dynamic, involving not just East Africa,

but the whole of the African continent.

Africa was a continent rich in diversity,

and climate acted as a sort of catalyst,

blending these various groups together.

And so, we were formed as a result

of a mosaic of these different populations across Africa.

It was our diversity,

our resilience in the face of climate change.

It shaped us, our minds and our bodies

and transformed us into a new and evolved human.

(goats bleating)

We all carry an echo of what happened in Africa

at this pivotal moment.

Because what happened then, changed us forever.

♪ ♪

What began as different, scattered populations...

...in the face of adversity, came together.

Propelling us to become one,

stronger, smarter species.

♪ ♪

This is a museum that houses

some of the most important fossils in the human story.

And one of those fossils is Herto1.

Easily, one of the most significant Homo sapiens fossils

that has ever been found

and that's because this individual

is one of the very first in our lineage

that we can describe as an anatomically modern human.

Its physical characteristics and traits

are overwhelmingly similar

to those of yours and mine.

And if you look at this individual

compared to Jebel Irhoud,

look how rounded it is.

Some people have put forward

this intriguing idea that perhaps

the shape of the skull

reflects a change in brain organization.

This evolution of a rounder skull

has been linked to coordination and language skills.

And it is really exciting to consider

that this change in shape

reflects a really significant shift

in the way that Homo sapiens were starting to think.

These reorganized brains had slowly but surely

opened a gap between Homo sapiens and our ancestors.

But it wasn't only the shape of our brains that set us apart.

One of the lines of evidence for this,

are actually the teeth.

Now scientists have discovered that if you look

very closely at the teeth, what you find

are very fine lines called Perikymata; they represent

about a week in the life of an individual.

So that means

you can count how long an individual has been alive,

a bit like tree rings.

The teeth can also reveal when they erupted.

That timing can be used to estimate

how close a child is to becoming an adult.

And so, if you look at a Homo erectus individual

and compare it to, say,

a Homo sapiens living today, our species

takes an incredibly long time to get to sexual maturity.

From the lines on their teeth,

we know that Homo sapiens children

were growing up slower than earlier humans.

♪ ♪

The thinking behind it is that we needed

a really long time to learn how to use these brains of ours.

And the longer

that you exist in childhood, the longer you have to learn.

And so, this thing that is a real headache

to so many parents out there today,

that our children take so long to become fully formed.

That might actually be a huge key to our success.

♪ ♪

Reorganized minds and longer childhoods.

Our brains and bodies had evolved.

At last, we were Homo sapiens who physically looked like us.

What you might call sapiens 2.0.

♪ ♪

It was some of these modern, evolved Homo sapiens

that found their way out into the wider world.

But beyond Africa was already home to other humans.

Neanderthals had spread across central Asia and Europe.

Other parts of Asia were populated

by multiple human species,

including Homo erectus.

And there is evidence in the Middle East

of an early group of Homo sapiens.

Who followed in the footsteps

of these other human species.

We're so used to living in a world with borders

that it is easy to forget that Homo sapiens at the time

had no concept of Africa.

And so, if the climate allowed,

they ventured out and expanded into new territory.

I do love thinking about

those huge moments in our history, like,

when Homo sapiens first left Africa.

It was a massive achievement, even though they would

have had no idea of the significance of it.

And it's amazing to think that it happened

so early on in our story.

But it's in the Levant that I think

things get really interesting.

♪ ♪

Evidence has been uncovered of Homo sapiens

living in caves in the Levant

in an area now part of Israel.

And it's in this place,

they would have encountered something unexpected.

There is one mountain called Mount Carmel,

where one cave called Skhul has been found

with Homo sapiens,

and another cave on the same mountain,

called Tabun Cave,

has been found with Neanderthal individuals.

And these two peoples

were living at around the same time.

(fire crackling)

It is kind of wonderful to think about.

(tapping)

Two species perhaps sharing the same mountain

at the same time.

We don't know if they interacted.

But we do know

that while Neanderthals remained in the region,

all traces of this group of Homo sapiens vanished.

Their bloodline died out completely.

What is most fascinating about these Homo sapiens

isn't who they met; it isn't even what they achieved.

It's that all of these early dispersals failed.

We know from genetic evidence that those Homo sapiens

are not the ones who would go on

to ultimately populate the planet.

This failed migration was a stark reminder

of our fragility.

These people looked like us.

But we don't know if they thought like us.

Because what would come to define our species

wouldn't be how we look

or even the size

of our brains.

But something else altogether.

While these early migrants vanished...

...populations in Africa thrived.

Coming together to manifest some behaviors

that feel very familiar.

(insects chirping)

These behaviors would set Homo sapiens apart.

And some of the earliest traces of this

can be found in a remote cave in Botswana.

Sheila Coulson has been studying this cave

since 2004.

And she has an intriguing theory

about what might have taken place here.

COULSON: This is obviously a very large natural outcrop.

And as you can see, goes on and on.

It's seven meters long.

The front has a natural slit for a mouth,

and a natural depression for an eye and even,

if you want to go that far, a nostril up at the front.

Right. With the head rearing up,

it does, in modern eyes,

look like a snake.

The overall form has been altered

to make it look even more snake-like.

(scraping)

There are over 300

indentations that have been ground into the surface

over what is obviously an extended period of time.

When the initial excavations were conducted,

they absolutely revealed a number of questions.

One of the things found was an extremely large number

of tools that appeared to be manufactured

and then just left there in pristine condition.

These look gorgeous, I mean, they're absolutely stunning.

COULSON: Once they were manufactured,

then you did one of three things with it.

You either manufactured it perfectly

and just left it. Hm.

Or more interestingly, you burnt it.

But not burnt to just, like, throwing it in a bonfire.

It's controlled burning.

And the third and most bizarre thing that they did with them

is they made it,

manufactured it perfectly

and when they were finished,

turned it over, smashed it in the middle.

AL-SHAMAHI (voiceover): This behavior suggests that people

were likely coming here to make offerings.

Which tells us something about how their minds worked.

COULSON: Although, it's absolutely magnificent during the daytime,

it comes to life at night.

You make an offering

and hope for something back.

Asking for probably some of the things that we would ask for:

food, health, children, etcetera, etcetera.

And you just think, oh my gosh, that's some of the...

...that's some of the earliest behavior

that we know so well.

(voiceover): Some scientists believe that the people who performed

these rituals were likely

holding abstract ideas in their minds.

(rock scraping)

When I see this, this is what moves me,

because this

is who we are, in a way

that feels more us than bones.

♪ ♪

We are, as a species, obsessed with ritual.

It is religion and spirituality,

or things like the handshake or birthdays,

graduation ceremonies,

Burning Man, Glastonbury, New Year's Eve.

Profoundly and fundamentally Homo sapiens behavior.

♪ ♪

This intriguing site hints at

how our mental abilities were developing.

Forming new connections that would

embed abstract thought into our behavior.

And this wasn't just confined to ritual,

it touched every part of our lives.

(insects chittering)

(hoofbeats pounding)

♪ ♪

By 70,000 years ago,

a sophisticated new weapon began appearing

across southern Africa.

Homo sapiens were using abstract thought to innovate,

inventing complex projectile

weapons like the bow and arrow.

We were seeing the world not just as it was,

but as it could be.

It takes a lot to see the potential

in a piece of wood.

Projectile weapons were revolutionary technology

for us humans, because up until now,

we'd been using closer range hunting strategies

which were less effective, less lethal,

and yet more dangerous for the person holding the weapon.

For over two million years,

early humans mostly relied on axes and spears.

But Homo sapiens took materials...

...and imagined how they could fit together

...to engineer a more powerful weapon.

One that is safer to use.

If you look at this bow and arrow,

you can see how much knowledge is required.

You need to know where to get the wood for the bow.

You need to know about the glue.

You need to know how taut the strings should be.

So many elements that require not just

knowledge, but the ability to pass that knowledge on.

Something like this is not the result

of one person's genius.

It's the result of many, many people over many generations

inventing, reinventing, perfecting, tinkering.

We weren't just inventing.

We were adapting

and expanding our knowledge.

Human culture

was becoming more complex.

The technology was exploding.

Now, many of us think that this is a result of something

called cumulative culture,

the idea that you accumulate culture.

So, every generation builds upon the previous generations'

science and technology.

Homo sapiens were displaying a degree of cumulative culture

that went beyond the other human species

and was growing.

And as our numbers increased,

this was more powerful than any weapon.

A giant leap towards becoming the species we are today.

♪ ♪

When was our species truly born?

Was it when we first appeared?

Or when we started to look like modern humans?

Or was it when our minds lit up?

(rock scraping)

Creating,

inventing and building on our knowledge?

Each was a crucial step in our evolution.

But none would be possible without one special ingredient.

♪ ♪

The glue that binds all of our achievements together.

It leaves no direct fossil evidence,

but we can find traces of it

in some unexpected places.

In archaeology, sometimes the smallest finds

actually tell the grandest of stories.

These are tiny marine shells,

and shells like this have been found in caves in South Africa.

And they are just too small to have been collected for meat.

If you look really closely,

what you see is that they have holes in them.

Now, some of these were collected because

they already had holes,

but others were perforated by Homo sapiens.

(bird chirping)

♪ ♪

And really close examination of the shells show

that they had wear marks on them consistent

with having been worn on the body.

So that, along with these

holes in them, well it's really easy to paint a picture

of them having been strung...

...and turned into jewelry.

♪ ♪

They were also painted red; these weren't just beads,

they were symbols of value and meaning,

shared and understood by many.

(waves crashing)

Perhaps you were trading them for food, for goods.

Perhaps you'd give them as some kind of a gift, at a wedding.

Perhaps they were just a sign of friendliness,

and you can also imagine that people

would be wearing them to make themselves look good.

It would perhaps be a sign of prestige.

The most remarkable thing about these shells

is that they have been found not just in South Africa,

but all over Africa, from the south,

all the way to the north in Morocco and Algeria.

And that for me is so exciting.

Because when you look at this,

you might think, oh my God, isn't that amazing?

Humans have a kind of cultural expression

that they never had before.

Homo sapiens were now sharing complicated technology,

rituals and traditions.

They were expressing

sophisticated ideas that likely required language.

While earlier humans probably had basic language,

it's thought that Homo sapiens were speaking

to each other in a different way.

♪ ♪

Culture connected our species,

possibly across the entire continent.

All over Africa,

we understood the cultural symbolism

of these beads.

Somebody was telling you, this shell is important,

not that shell.

Red is important, not the other colors.

We had an understanding

that wasn't just you, me and our three families.

You, me and the village next door.

We had a kind of symbolism and understanding

and interconnectedness that was continent-wide.

♪ ♪

Our species' birth wasn't a single moment,

it unfolded over millennia.

Complex language and our powerful shared culture

were the final elements setting us apart from other humans.

No longer scattered groups,

we had become one connected, cooperative species.

We had become Homo sapiens.

The ancestors of us all.

Sometimes in life things come together

and this was a coming together for our species.

It was a perfect storm.

You had a change in brain.

You had language, increased numbers,

increased connectivity, cumulative culture,

better technology and weaponry, and the right climate.

But through all of this,

there was a hidden thread.

Our secret weapon is that we are

a social, cooperative species.

Friendliness, it turns out, is our superpower.

We are more than the sum of our parts,

whether it's ritual, technology, language,

all of it comes down to cooperation, in my opinion.

And that's how you go from a species

that started off feebly, unremarkably,

to one that would become so extraordinary,

one ready to explore this planet.

♪ ♪

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