Secrets of the Dead (2000–…): Season 12, Episode 4 - Cavemen Cold Case - full transcript

ANNOUNCER: Coming up,

the remains of an ancient people
are discovered buried

deep within a cave.

TRANSLATOR: This one was
just another cave,

but it proved more interesting
because it was like a container

of rather unusual remains.

ANNOUNCER: But did those remains
belong to humans?

It is not typical
for where we find
Neanderthal occupations.

ANNOUNCER: And a discovery
raises troubling questions

about our Neanderthal ancestors.

Cannibalism was why
those bones got there.



ANNOUNCER: "Caveman Cold Case,"
on "Secrets of the Dead."

Captioning made possible by
Friends of NCI

ANNOUNCER: "Secrets of the Dead"
was made possible

by contributions to your PBS
station from viewers like you.

Thank you.

NARRATOR: Deep inside a remote
cave system in northern Spain,

a gruesome investigation
is underway.

It involves the partial remains
of a group of people.

They were discovered
in March 1994,

when cavers exploring
the El Sidr?n cave system

climbed into
a small side gallery

off of the cave's main tunnel.

Hey, I found something.

Looks like human bones.



NARRATOR: The remains are
reported to authorities,

and partial skeletons
of 4 humans are exhumed.

The bones are in pieces.

Police and cavers note that
the bones don't look very old,

certainly no older than
60 or 70 years.

They believe they are
looking at the remains

of victims of
the Spanish Civil War.

They couldn't see yet
that there were cut marks
on the bones,

clear signs of cannibalism.

NARRATOR: In Madrid,

investigators compared the bones
to other human remains,

but they did not belong
to the war victims.

These bones came
from another time

and belonged
to another people...

Neanderthal.

From the cliffs of Gibraltar

to the depths of El Sidr?n cave,

scientists must reach
back in time

to identify the dead

and reconstruct
their final days.

But can they find
enough evidence

to crack this prehistoric
cold case?

Below this valley floor lies
the El Sidr?n cave system.

Here, a forensics investigation
has been in progress

for more than a decade.

The location where
the bones were found

is now known
as the Ossuary Gallery.

Every year, more
and more relics are exhumed,

and the number of dead rises.

Scientists across Spain
have joined forces.

Human fossil expert
Dr. Antonio Rosas

leads the investigation...

Dr. Carles Lalueza-Fox,

a world-renowned geneticist
from Barcelona,

hunts for ancient DNA...

and archaeologist
Dr. Marco de la Rasilla

is in charge of the excavation.

He is on his way from
the University of Oviedo

to the annual dig.

He's headed to a river valley

in the Asturias region
of northern Spain.

[Church bells ring]

Most of the young researchers
who join the dig

are Marco's students.

They come every summer to spend
up to a month working the site.

[Generator engine buzzing]

The Ossuary Gallery is more than
700 feet from the main entrance.

The entire tunnel stretches
for nearly two and a half miles.

The cave can sometimes be
an extremely dangerous
place to work.

Rain from above ground
can cause flooding,

and a puddle can quickly grow
into a raging torrent.

[Dripping of water echoing]

The Ossuary Gallery,
where the bones are found,

is slightly higher than
the main gallery.

It's safe from flooding,
but not from looters.

In the first years of the dig,
fossils were stolen.

A steel cage now keeps
the precious remains safe

75 feet below the earth.

[Man speaking Spanish]

TRANSLATOR: Because we're used
to working in caves,

this one was just another cave,
but it proved more interesting

because it was like a container
of rather unusual remains.

NARRATOR: Remains that would
take years to unearth,

transforming the once tiny
gallery into a chamber of mazes.

The site is cramped
and difficult to traverse,

but in this confined space,

more than a thousand
human bone fragments

and hundreds of stone tools
have been found so far.

Every single piece
of bone and rock,

and the soil from which
these items are excavated,

is examined,
cleaned, and logged.

The stone tools are Mousterian,
the same as those found

in a typical Neanderthal's
tool box.

But the mystery
of their presence here,

alongside so many human bones,
has haunted the scientists

since the very first day
of the excavation.

[Speaking Spanish]

TRANSLATOR: Once we had started
the excavation in El Sidr?n,

the big question was, what were
the human remains doing there?

We didn't know
what it was used for.

It could have been a home,
a burial ground,

or the remains could have come
from somewhere else

and were in
a secondary position.

We just didn't know.

NARRATOR: As the bones
and stone tools are excavated,

and their exact location
plotted,

it seems they are all in
the same layer of ancient soil--

3 feet deep, 18 feet square--

and they find something else.

Random dating reveals the relics
are all around the same age--

49,000 years.

It looks as if something,
or someone,

buried these relics here
at the same time.

John Hawks is a human
evolution expert.

He has visited dozens
of the world's most important

Neanderthal sites
and collections.

At the Vienna Natural
History Museum,

a much-awaited human
evolution exhibition

has just opened
its doors to him.

As a Neanderthal specialist,

he has watched
the unfolding investigation

at El Sidr?n
with great interest.

The cave is unlike
most other Neanderthal sites.

HAWKS: When an archaeologist
is excavating a site

and he finds things
that are together in
a fairly narrow layer,

that still doesn't mean
that they were deposited
there at the same time.

Time is compressing.

There could be hundreds,
maybe even thousands of years,

in that archaeological deposit.

It's very rare to come across
a place like El Sidr?n,

where it looks like things
might have been deposited
at the very same time.

NARRATOR: Neanderthal sites
usually contain evidence

of everyday life,
like the bones of animals

they used for food and clothing,

but the bones of people
are scarce.

El Sidr?n is just the opposite;
it has very few animal bones

and a large amount
of human remains--

further evidence the remains
were deposited in the cave

at the same time.

HAWKS: The cave at El Sidr?n
is a cold place.

It doesn't look like it would be
a great place to live,

especially where
you find these bones.

It is not typical for where
we find Neanderthal occupations.

[Birds chirping]

NARRATOR: Neanderthal occupation
sites were open to fresh air,

but also protected.

Their real estate ranged from
the humble rock shelter

by a quiet stream...

to cathedral-like rock towers
along the Mediterranean.

Scientists are studying both of
these contrasting environments.

But who were the Neanderthals?

HAWKS: The Neanderthals
were the people that occupied
the western half of Eurasia--

basically central Asia, Europe--

from 300,000 years ago or so
up to about 30,000 years ago.

They were always
a very small population,

maybe less than 50,000 people,

and they lived in a climate
that fluctuated widely

from relatively warm
periods like today

to very cold,
glacial conditions.

[Wind howling]

We used to think of Neanderthals
as being basically hunters,

and they were eating a very,
very high proportion of meat.

We've begun to find evidence
that they were making use of
a wider range of resources.

They were masters of knowing
what foods were available in
their environment.

We know from their genetics that
Neanderthals are a part of us,

but they're not the same as us,

and so, when we look at them,
we have to make that adjustment

that we're looking at somebody
very close to ourselves,

but maybe not quite
like ourselves.

NARRATOR: Inside El Sidr?n,

investigators work to uncover
a time and a people

we can scarcely comprehend.

The truth behind
what happened here

can only be deduced from
a thorough forensics
investigation.

The scientists already know
El Sidr?n was not
a typical Neanderthal home,

and they know
the stone tools and bones
were all buried together

around 49,000 years ago.

But can they find out
why they are here,

and who or what brought them
into this place?

The first clue comes
from the bones.

In Madrid,
Antonio Rosas struggles

to refit the Neanderthal remains

to find out how many people
are in the cave.

In the process, he discovers
what really happened.

He's found cut marks

in significant places
on leg and jaw bones.

[Rosas speaking Spanish]

TRANSLATOR: This means
that parts of the bodies
were cut

with the intention
of ripping away the flesh.

NARRATOR: Some of the bones
have been cracked by force.

[Rosas speaking Spanish]

TRANSLATOR:
Here we can see an impact mark
on this leg bone fragment.

This means that
the bone has been struck

and broken with a stone
in order to reach

the bone marrow inside,
which is very nutritious.

NARRATOR: Evidence enough
for Antonio Rosas

to come to a conclusion.

TRANSLATOR: In El Sidr?n,
there was an incident
of cannibalism.

It is really some of
the strongest evidence
that we have

from any Neanderthal site
that cannibalism was why
those bones got there.

NARRATOR: But can we know
who cannibalized
these Neanderthal people?

Was it our Homo sapien
ancestors?

HAWKS: Toward the end
of their existence,
after 40,000 years ago,

the Neanderthals declined
in numbers, they declined
in geographic range.

It's obvious we had something to
do with it because modern humans
show up in Europe at that time.

But at the time of El Sidr?n,

there are no evidences
of modern humans being
anywhere near the area,

so it looks like Neanderthals
were responsible,

at least as far as the evidence
we have right now.

NARRATOR: So why did these
people turn to cannibalism?

HAWKS: When we want
to understand

why Neanderthals would have
turned to cannibalism,

we have to look at
the circumstances in which
humans become cannibals.

HAWKS: When you look
across human cultures,

it happens surprisingly often.

It happens, in a lot of cases,
because of hunger.

It's true desperation,
where the only food source

you have available to you
is the bodies of your dead,

or maybe not yet dead, comrades.

There are
other contexts, though.

There are ritual contexts,
in which you're trying
to capture

the spirits of dead people
who may have been dear to you.

There are contexts where
you've conquered people,

and you want to capture
their energy by eating
their remains.

It is truly culturally
complex in humans,

and we have no reason to think
that in Neanderthals, it would
have been less complex.

[Rosas speaking Spanish]

TRANSLATOR:
What is the real significance of
this occurrence of cannibalism?

Are they symbolic
or cultural reasons?

At the moment, we don't have
any evidence to show
that a ritual occurred here.

NARRATOR: Were all
Neanderthals cannibals?

We're beginning to find
that they were as diverse
a group as modern humans.

Like us, they lived
in different environments

and probably had
different lifestyles.

To place the El Sidr?n
cannibalism in perspective,

scientists are exploring
a completely different site

at the other end
of the Iberian Peninsula.

Here, there is a rock cliff that
served as a Neanderthal refuge,

but no evidence of cannibalism
has ever been found.

Clive Finlayson is
an evolutionary ecologist,

and he thinks he's found
a Neanderthal Shangri-La.

FINLAYSON: As you come round
in a boat and look
at this cliff face,

you don't just see
one cave, Gorham's Cave.

You see another cave
and another cave,

and others going underwater,
and they were all occupied
by Neanderthals.

[Sea gulls crying]

This was the Neanderthal city.

NARRATOR: El Sidr?n
is dark and cool,

but the path to Gorham's Cave
is bright and hot.

FINLAYSON: The Neanderthals
had been living in Gibraltar
for a long time,

probably much longer
than 60,000 years ago.

The surprising thing here
was not when they started,
but when they finished.

And we found a half a campfire

at the top of Gorham's Cave
which we excavated,

and we took samples
for radiocarbon dating,

and the surprising result
that came back was 28,000 years.

That makes them
the most recent population

of Neanderthals to have survived
anywhere on the planet today.

NARRATOR: El Sidr?n's story is
of a single instance in time.

Inside the Gibraltar cave,
events that happened

over tens of thousands of years
are being pieced together.

Clive's team has excavated
hundreds of stone tools

believed to have been made
by Neanderthals.

His partner,
underwater archaeologist
Geraldine Finlayson,

has been working at the site
with Clive since 1997.

GERALDINE FINLAYSON:
For a long time,

Neanderthals were thought
to have mainly been eating meat.

But we find, certainly
in this part of the world, that
they eat a lot of shellfish,

and here behind me,
we've got different layers
like layers in a cake,

and scattered among the layers,
you can still see the remains of

the shells that
they have collected.

We also find fish bones
and fish scales inside the cave.

It's very easy to collect fish,
so you don't need a rod or
a line to catch a fish.

Simply just toss a stone
at them, you can knock them out,

so they can be
quite easy to catch.

CLIVE FINLAYSON:
They ate all kinds of things,
whatever was out there.

If you put it together,
all that's missing

to make a good Mousterian
Neanderthal paella is rice.

Outside the cave,
the view is not the one

the Neanderthals would have had
for most of the time.

The sea level was much lower
because the global climate
was much cooler.

The coast was
4 to 5 kilometers out.

The seabed, which is
well-submerged now,

would have been the landscape
where they went out, hunted,
and gathered,

and then they came back
into this cave for shelter
and protection.

NARRATOR: Geraldine
and her dive buddy,

archaeologist Darren Far,
are about to visit a site

where Neanderthals lived
when sea levels were much lower.

It is a strange landscape.

Large pinnacles,

some with freshwater springs
at the base,

rise up from the seabed.

It's a unique and very new
investigation.

FAR: We can see valleys,
we can see river gullies,

and we actually found
upwellings of freshwater.

So they would have had
a lagoon-type system
in front of the cave,

so you can imagine that would
have attracted water birds,
a whole bunch of other things.

So it was actually quite
an idyllic landscape

for them to survive in,
possibly explaining why
they lasted here so long.

NARRATOR: Rocks collected
from these pinnacles
will be compared

with the stone tools found
in the Gibraltar cave site.

But the real work lies ahead.

Using techniques
usually seen on land,

the team must set up grid lines

and meticulously record
what they find underwater.

If Neanderthals did live here,

perhaps their bones are
still buried at depth.

But because they are now
90 feet below the surface,

after only 20 minutes,

they have to leave the site
or risk the bends.

Finding evidence here
will be a slow process.

And the past does not give up
its secrets easily.

Deep within El Sidr?n,

the scientists now know
Neanderthals were cannibalized

by their own kind,
but their task is not over.

Finding out how the remains
and tools actually got

into this cave will require
extraordinary detective work.

For the scientists,
figuring out how the bones

and the stones ended up
in this place in the cave

was really the breakthrough.

NARRATOR: The discovery comes
when Marco and his team are back

in their lab at
the University of Oviedo

and take a closer look
at the stone tools.

El Sidr?n is not a place
where Neanderthals lived,

but among the many
excavated stone pieces,

they find proof of
the manufacture of stone tools.

[de la Rasilla speaking Spanish]

TRANSLATOR: We found evidence
of the production of what
we call lithic flakes.

NARRATOR: These flakes
are the by-product

of a core rock being struck
to make a tool.

[Speaking Spanish]

TRANSLATOR: With this tool,
you can cut meat, make other
tools, and even crack bones.

It's as sharp as a razor blade.

NARRATOR: Looking closely at
the edges of the lithic flakes

and what they believe are
the core rocks,

Marco's team sees a pattern...

...and attempts
to refit the pieces.

Here is irrefutable
evidence of a moment

49,000 years ago,

when someone made stone tools.

But these tools were not made
inside the El Sidr?n cave.

If they were, some of the flakes
would have been found

close to each other
when they were excavated.

Experiments have shown
that flakes don't scatter,

but the fitted pieces
here were found

up to a yard away
from one another.

It's as if they'd just dropped
into the Ossuary Gallery
from above.

The team finds many more
stone flakes, rock cores,

and bone in a configuration

familiar to scientists.

When all the finds
at the site are plotted,

another pattern emerges--
a cone shape.

It's known as a debris flow cone

and is a common
geological phenomenon.

HAWKS: In El Sidr?n,
we have a cone of sediment,

and it represents something
that just fell into the cave.

[de la Rasilla speaking Spanish]

TRANSLATOR: When this geological
phenomena occurred,

everything moved inside,

so logically, everything
appeared together.

NARRATOR: And the stone tools
used to take flesh from bone

are still as sharp
as the day they were made.

[de la Rasilla speaking Spanish]

TRANSLATOR: The fact that
everything appeared together
inside the cave means

there was a clear activity
related to cannibalism,

and the stone tools were
used for that purpose.

[Dripping water echoing]

NARRATOR: The El Sidr?n
investigators find
a logical point

where the bones
and stone tools entered,

right above
the Ossuary Gallery,

but it no longer opens
to the surface.

The real story of what happened
to the people of El Sidr?n

lies outside the cave.

The karst landscape above
the cave is constantly
reshaping itself.

Huge sinkholes appear when
acidic rain dissolves
the limestone.

They will eventually crumble
into caverns below.

But the collapse in El Sidr?n
was not a slow process.

If it were, the remains
would have been scavenged.

Wolves and other predators
shared the Neanderthal's world.

[Rosas speaking Spanish]

TRANSLATOR: The fact
that there were very few
carnivore teeth marks

shows us that the bones,
the bodies, were only exposed
to the air for a short period.

The burial process
was very fast.

HAWKS: It is amazing how many
things had to fall into place

in order for all of this
evidence to tell us
what happened

at a moment in time in
the Neanderthal life.

And that evidence
in the archaeological record

is so rare, so lucky,
that it just--

it blows my mind that we're
able to figure out

what happened at
a particular moment.

NARRATOR: La Cabani?a
is near El Sidr?n.

The investigators believe
a shelter like it

could have been directly above
the Ossuary Gallery

49,000 years ago.

[Water flowing]

In ancient times,
there was a stream nearby,

similar to the one that runs
near La Cabani?a today.

The scientists suspect
that a huge storm caused
flash flooding,

resulting in a sudden collapse

that brought the Neanderthal
remains into El Sidr?n.

[Man speaking Spanish]

TRANSLATOR: The cave must have
been practically like it is now,

and in the same way we could
live here, they could have
done so in the past.

There is a roof, water,

the basic conditions
that they would have needed.

There is also silex,
the material they used
for their tools.

They would have
lived here very happily.

NARRATOR: But there was death.

The El Sidr?n investigators
believe they know what happened

in this ancient cold case.

It started with a storm.

[Thunder]

[Water dripping]

HAWKS: This is the first time
that we have a discovery like
this with Neanderthals,

where you have a group of
individuals that probably knew
each other when they were alive.

NARRATOR: Now, the greatest
challenge facing the scientists

is to give these people back
their identities.

The bone fragments don't
fit together to make even
one whole person.

In Madrid, Dr. Rosas
and his team have spent
a decade trying

to get to know the Neanderthals
of El Sidr?n better.

He has led a meticulous
forensics investigation

to find the age, sex,
and health of the victims.

Each year,
more evidence is exhumed

and the death toll rises.

It started at 4

and is now much higher.

For scientist
Almudena Estalrrich,

the teeth hold the key to
identifying each of the bodies.

[Estalrrich speaking Spanish]

TRANSLATOR: We know that the
teeth belong to a certain kind
of individual for many reasons.

In the first place,
the wear is the same.

In other words, all the teeth
are in the same state--

eroded or not eroded--

and mainly because of the marks
on the sides of the teeth,

caused by friction, so they
serve as a kind of fingerprint.

They're the same now
as when the teeth were together.

NARRATOR: In this way,
they discover a much higher
death toll than expected.

[Rosas speaking Spanish]

TRANSLATOR: There are
12 individuals represented--

6 adults and 6 children.

Among the children, there are
3 teenagers close to maturity.

There is one child
around 5 years of age,

another approximately
8 years old,

and a very young one
of around two years of age.

NARRATOR: The investigators know
the Neanderthals' age and sex.

They know they were cannibalized

and how they ended up
inside the cave.

But there is one more thing
they hope to find,

something that may offer
the ghosts of El Sidr?n

a type of immortality--

their ancient DNA.

Genetics.

The new wave
of Neanderthal research

is about to take
the investigation
into another realm.

In Barcelona,

Carles Lalueza-Fox wants to give
ancient peoples an identity.

LALUEZA-FOX: I wanted to try
to provide an image
of the Neanderthals

that could be not just genetic
Neanderthals, but persons

with their own traits,
like just in modern humans.

NARRATOR: At the Institute
of Evolutionary Biology,

Dr. Lalueza-Fox specializes
in the extraction

and analysis of ancient DNA.

LALUEZA-FOX: Because we are
alone, and we know for sure
that we have been alone

for thousands of years
in this planet,

we don't have the concept
of what different
human species would be.

For us, it's very difficult
to imagine someone
who would be, at the same time,

very similar to us,
but also at the same time
fundamentally different to us,

and that is what
the Neanderthal would be.

[Dripping of water echoing]

Going into the cave,
I discover that was
a very special site,

probably a unique site because
the temperature was so stable
all along the year,

and it has been stable
during at least 50,000 years.

And I thought we are going
to find DNA preserved
in Neanderthals.

It's going to be there.

I was given a tour first

to check if there was
Neanderthal DNA in it.

After several weeks, I was able
to retrieve Neanderthal DNA

from that particular tooth,
but I also discovered

that the tooth was plagued
with Homo sapiens' DNA.

NARRATOR: Our human DNA is
very similar to Neanderthal DNA,

which makes separating
the two difficult.

The moment El Sidr?n
was discovered,

cavers, police, and even
scientists contaminated
the remnants

of the Neanderthals' DNA
with their own.

LALUEZA-FOX: It's difficult
to believe, but if you
breathe over the bones

or you touch a particular
bone fragment

or a Neanderthal tooth,

your DNA can go from the outside
into the inside of the specimen.

NARRATOR: Carles knew
he could not waste this
extraordinary opportunity.

LALUEZA-FOX: I decided
to implement an anti-
contamination protocol

at the excavation itself.

I put my lab
into the excavation.

NARRATOR: Now, a bone
to be tested is not exposed

until the dig is stopped,
the site is locked down,

and the excavator suits up
in sterile gear.

Carles also ensured that the DNA
of everyone who comes close

to the remains is recorded,

so he can eliminate their DNA
signature from his results.

LALUEZA-FOX: We were able
to know exactly who was
contaminating the remains,

and we were also able to compare
the Neanderthal sequences

with all the sequences of
the people that had been

not just touching the remains,
but close to the remains,

into the excavation itself.

NARRATOR: The El Sidr?n protocol
will change the way

ancient DNA is
collected and tested

throughout the world.

In his hands,
Carles may hold clues

to identifying some of
the El Sidr?n victims.

[Electric drill buzzing]

The bone powder drilled
from inside the sample

will need to go
through many processes

before Carles will know
if his protocol has been
successful.

And if DNA is found,
it will be in fragments

that will have to be
magnified, replicated,
and reconstructed.

He's looking for nuclear DNA,

which is responsible
for an individual's traits

and is passed down
from both parents.

The El Sidr?n bones will
help create a new vision
of Neanderthals.

LALUEZA-FOX: We had an image
of what Neanderthals could
look like,

and what we could say is
that Neanderthals had,
likely, red hair...

they were O blood group...
[Heart beating]

they were able to have
this bitter taste perception,

and they probably had
language abilities like us.

NARRATOR: This is the first
model of a Neanderthal created
using genetic evidence.

Carles has given physical traits
to a female from El Sidr?n...

but he still wants to know
if members of her group
were related.

To find out, he must look
for another type of DNA.

Mitochondrial DNA is passed down
from mothers to their children.

Because it changes
at a very predictable rate

over generations, it can be used
to trace lineage back

to ancestors who lived hundreds
of thousands of years ago.

Finding it will establish
whether this group of 12
were related.

The people of El Sidr?n,
they were family-related.

We don't know exactly
which were the relationships,

but we know they were
family-related.

All the 3 adult males
had exactly the same
mitochondrial DNA,

while the 3 adult females had
different mitochondrial DNA,

which is shown in modern
hunter-gatherer groups

where the females move
from one group to other,

while the males stay
in their paternal family group.

NARRATOR: Two of the women were
directly related to children
from the group,

and could have been
their mothers.

Here is the first real proof of
a Neanderthal social structure.

Here's a case where we have
maternal relatives.

That does tell us
something about the way

that ancient human groups
may have begun to be composed.

For this set of Neanderthals,
what looks like happened is

that the women were going
from one group to another,

probably at the time
that they began to mate,

and so that tells us how
the genes are moving across
Neanderthal populations.

They're moving with women.

NARRATOR: Marco de la Rasilla
has found proof that groups

did exist in the area and that
they were on the move.

[de la Rasilla speaking Spanish]

TRANSLATOR: The silex we have
discovered here was used
by these groups,

but it can also be found
in other areas near and far.

Therefore, we can conclude
that they moved around
and took raw materials

from one place to another--
for hunting or for work--

for what they needed on their
journeys to different places.

HAWKS: When you start losing
little groups because things
become harsher,

then you have a situation that
puts the entire population
genetically at risk.

They can't maintain
their adaptability
to new circumstances.

NARRATOR: The death of a family
could have isolated the
surrounding groups even further.

The distances to exchange
females would eventually be
too great.

Over time, the resulting
inbreeding would halt

the vital flow of genes
that leads to evolution.

HAWKS: We can see an event
here where we had people
that were very hungry,

where they were not able
to survive without turning

to cannibalism, and that puts
the entire survival

of this broad population
into a very interesting context.

NARRATOR: So why did populations
of Neanderthals begin to shrink?

Some say our arrival in Eurasia
was the beginning of the end.

Clive Finlayson believes
climate was the killer.

CLIVE FINLAYSON: Climate change
affected the environments

that these people occupied
across central parts of Europe

and even central parts of Asia
and even northern Europe.

NARRATOR: Ice core data
shows that between 50,000
and 30,000 years ago,

the climate see-sawed
between warm, wet periods

and cold, dry periods.

The El Sidr?n act of cannibalism
coincides with the latter.

CLIVE FINLAYSON: As that climate
changed their landscape,
their environment--

which was a wooded environment
where they would ambush-hunt
animals--

began to shrink.

Gradually the population was
being pushed back, back, back

into these strongholds
like the one we find here.

They were becoming
like pandas or tigers.

The populations were
isolated from each other,

and there was very little
gene flow between them,

and therefore they were
suffering from inbreeding

and all the kinds of effects
that small populations have.

They were there,
but their days were numbered.

Those Neanderthals
were living dead.

NARRATOR: So far, there is
no evidence pointing to climate

as the killer at El Sidr?n,
but these Neanderthals

would have needed to consume
a huge amount of food.

Getting enough energy to survive
even an ordinary winter would
have been a challenge.

[Rosas speaking Spanish]

TRANSLATOR: It is thought
that the composition of
the Neanderthal body--

not only because
of its size, but also due
to the muscular thickness

of the limbs and torso--
needed a large amount

of daily energy
for its metabolism.

This means that an individual's
daily consumption of calories,

proteins, and other nutrients
must have been very high.

Thus, certain unfavorable
environmental conditions

could have led
to physiological stress

brought on by food shortages.

NARRATOR: But we do know what
some of the family ate during
their lives at El Sidr?n.

The teeth of 5 family members
have been analyzed,

and calcified
dental plaque removed.

HAWKS: On the surfaces of teeth
of any kind of human,

we sometimes will find
calcified plaque.

Your dentist scrapes that off.

You know, it's hard work
to get it off of there,

but what it's doing is it's
capturing little particles
of the food that you eat,

and those little particles
include micro-fossils.

From that, you can tell
what kinds of plant foods
were being eaten.

NARRATOR: Molecules
of cooked grains

and also traces of bitter
green plants were found.

The presence of bitter plants
has led to speculation

that these people were using
plants as medicines.

HAWKS: El Sidr?n puts this
really interesting perspective

on this new evidence
about plant utilization because

when we look at those people,
we would initially look at them

and say, "Look at the breadth
of resources that they're using.

They're masters of knowing
what's in the landscape."

But at the same time, we know
that they're in a population

that has times of real
desperation, and so when we look

at the evidence of these
bitter plants on their teeth,
what we begin to think is,

"Oh, maybe they're really
stretching to the limit,

trying to get every
possible food that they can,"

and at the end, it just
didn't go well for this
small group of people.

NARRATOR: A family was
wiped out in El Sidr?n,

eaten by their own kind,

perhaps in an act
of desperate hunger.

HAWKS: When we look across
Neanderthal sites
all over Europe,

we see clear signs of stress.

We see their teeth are having
problems when they're forming,

which represents,
you know, times of hardship
when they're growing up.

We see evidence of hard lives
all over their skeleton,

and El Sidr?n is
one piece of evidence

that's really consistent
with the entire picture.

Neanderthal lives were,
in many cases, hard.

NARRATOR: Eventually,
that population was
whittled down to one person.

That last Neanderthal
may have lived in a place

where food was always plentiful.

CLIVE FINLAYSON:
At the time of the people
living in El Sidr?n--

in that more cold, northerly
climate, they're really having
it hard, to the point that

they're eating each other--the
Neanderthals down here carry on
doing what they've always done.

For a quarter
of a million years,

there's very little change
in this part of the world.

The climate is fairly mild.
It gets slightly dry and
slightly wetter.

But then, at 28,000 years,
the cores tell us there were
a series of droughts.

There was a period
which got really harsh--
not cold, but dry--and not only

did the Neanderthals
disappear from here,
but nobody else lived in here,

and that is quite telling,
I think, that Neanderthals
survived

for a quarter of a million
years, and we suddenly lose
their signal

when we get the worst
climactic conditions registered

by the marine cores
outside this cave.

GERALDINE FINLAYSON: It must
have been really very sad
for the last few people

to stay here and maybe realize
that they didn't come
into contact

with other groups
like they had been used to.

There must have been
the last one, and I always feel

quite emotional
when I think about them.

NARRATOR: 1,800 bones
and 400 stone relics
have been recovered.

But this is not the end
of the story.

There may be more bodies
in the cave.

Antonio Rosas
and Marco de la Rasilla

will soon take this year's finds
back to their laboratories
for analysis.

[Speaking Spanish]

TRANSLATOR: Until now, there
has been no archaeological
site in the world

that has produced
a greater number of bones
than in El Sidr?n.

It is an exceptional site
on all counts.

Finding a hundred
well-preserved
Neanderthal remains

at the same site every year
is highly unusual.

The extraordinary level
of fossil preservation

also makes this place
absolutely unique.

TRANSLATOR: There is
nothing to add.

It's just unique.

HAWKS: There's no limit
to what we will discover

as we get more and more methods
of looking at this evidence.

HAWKS: What a hard life
these people led, and what
a terrible way to go.

We still can appreciate
their lives and really begin

to understand how they fit
into this long term of existence

of a very mysterious group
of people.

NARRATOR: They have been in
the dark for 49,000 years...

and have only just begun
to tell their secrets.

ANNOUNCER: "Secrets of the Dead"
was made possible

by contributions to your PBS
station from viewers like you.

Thank you.

Captioning made possible by
Friends of NCI

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