All language subtitles for BBC - Ape-Man, Adventures in Human Evolution 2 - First-born

25 ,000 years ago, the domination of the
world by our species had led to the

extinction of all other pre -human
ancestors, the creatures who began our

evolutionary journey.

At a place called Taung in South Africa,
archaeologists have uncovered

extraordinary evidence for the very
start of the human story.

The skull of a young pre -human creature
many millions of years old, an ancestor

from our deepest past, and its hostile
world.

The youngster wandering off a little
from the rest of the family could easily

have fallen a ready prey for a passing
eagle.

And down it came and snatched this head
off.

And carried it here into town 2 .6
million years ago.

Searching for our first human origins
means looking for traces of a world that

is millions of years old.

Evidence is almost impossible to find.

And the most fundamental question, why
human beings should have evolved at all,

is still a matter of great mystery.

Scientists everywhere are looking for
the oldest creatures that might still be

called human ancestors.

These creatures must hold the key to who
we are and where we came from.

And every now and then, there's a
discovery.

Embedded in the rock are the ghostly
fossilized traces.

of a drained creature.

It's likely that it fell in. You see
it's at the bottom of this slope, and it

could have come in through the original
entrance 25 metres above us, not have

been killed by the fall, but actually
tried to find its way out and died here

the bottom of the slope.

The layer of rock the bones come from is
over 3 million years old.

The lower bones of one leg have already
been chiseled free, but the rest remains

trapped deep in the rock.

Ron Clark believes that what he has
already found suggests that a complete

skeleton may still lie beneath the
limestone.

In the intervening space, I'm hoping
that I'll find the rest of the skeleton,

that is, the vertebrae, the pelvis, and
the upper parts of the leg bones.

The outline of a head is just visible,
still connected to a thin strand of the

spinal column.

The teeth are clearly preserved.

Here, deep in the rock, is what
scientists think may well be one of our

ancestors, a pre -human, far away from
the dark forest where its kind once

three million years ago.

We study human evolution to understand
who we are, and we really can't

understand who we are.

unless we go way back to the very
beginning of the journey.

We need to know who these very first
ancestors were, why they evolved, what

looked like, how they lived.

Because without being able to answer
these questions, we don't know where we

began. We don't know where we came from.

When people started to think about
evolution, it became immediately clear

them that there was one group of animals
that was the most similar to humans in

their body form.

And these were the primates, the monkeys
and apes.

This is a young chimpanzee, and you can
see what they met.

In the skull, the eyes face forward.

If we come down the skeleton, the hand's
very similar to a human hand. The

thumb's short, but it has the same type
of grasping ability. It can manipulate

objects just like humans can.

Now, if we're going to look for the
earliest evidence of the human line,

very logical to look for this evidence
in the same area of the world where you

find our closest relative.

And this is why people are focused on
Africa.

A storeroom near Johannesburg is home to
the fossilized skull of the young

creature that died at Taung.

The skull has a special place in the
science of human origin. It has done

than any other discovery to unlock the
mystery of our evolution.

Here is the box that contains South
Africa's crown jewels.

The layer of rock out of which it
emerged is about 2 .6

million years old.

The little creature, about three or four
years of age when it died.

That would have been a fantastic find if
that's all had come to light. But in

fact, there was more.

The brain of this small creature has
also been fossilized.

Blood vessels, arteries, even veins.

a miraculously still intact two and a
half million years later. And for

scientists, it is this living detail
that sets the Taung child apart.

I do not think that there is another
find which has made more of an impact

on man's understanding of his origins,
his quest for his roots.

The skull was blasted to the surface at
Taung, on the southern edge of the

Kalahari Desert, where miners were
quarrying for limestone.

A few weeks later, the skull arrived in
Johannesburg, sent to a man called

Raymond Dart.

He was a professor of anatomy, not an
archaeologist.

And it was something about the actual
shape of the skull that first seemed

strange.

Although clearly ape -like, it didn't
seem to correspond to any creature past

present that was known to science.

A person of lesser imagination and
initiative

might have dismissed this as a sort of
beat up chimpanzee.

The differences were minute, but for
Dart, unmistakable.

He could detect that the canine tooth
was smaller than the

canine tooth of a chimpanzee.

The face was more vertical.

than the very snouty face of a
chimpanzee.

And then, on the base of the brain cart,
Dart found

evidence that the head had been held on
a much more upright spinal

column than in the case of the apes,
where the column is oblique and the head

tends to hang forward in that fashion.

On the other hand, the brain size was
ape -like, and not

nearly of the size to be found in a
modern human child

of approximately the same age.

Sensing that this mix of ape -like and
human -like features were the signs of a

creature in the midst of great change,
Dart realized he had discovered a new

species.

He named it Australopithecus africanus,
the southern ape of Africa.

A creature two and a half million years
ago which had taken decisive

steps. in a human direction.

Professor Tobias himself made a
startling set of discoveries.

They began to answer the mystery raised
by the tiny fossilized skull.

Why, millions of years ago, were human
-like features starting to appear in

African apes?

What was causing the change?

Here, at another limestone quarry, was
extraordinary new evidence of these

apes, the strange Australopithecines.

Tobias uncovered a vast horde of fossil
bones, mainly of long -extinct species

of hyena and giraffe.

But strangely, the bones he found seemed
to have been broken deliberately, even

violently.

And when Tobias mentioned the discovery,
Dart became agitated, travelling to the

quarry to examine the broken bones for
himself.

Dart became very excited by these
because he thought he could detect

consistent set patterns of breakage
which were recurring again and

again. And you can see how it's been
cut.

With an axe, a primitive axe in order to
give it its sharp.

And he came to believe that those were
deliberately fashioned in a kind of

stone, a bone age culture preceding the
stone age culture.

And it could be used as a remarkable
dagger and even as a more formidable

Dart's breakthrough was known as the
killer ape theory, and it was his answer

how apes became us.

In creating crude weapons from bone to
survive in their violent world, Dart

thought the Australopithecines were also
evolving the beginnings of an

intelligence that would one day lead
them to humanness.

This primitive hyena jaw could rip up a
belly. With a weapon like this, they

could gouge out the eyes of any animal.

Dark thought he had solved the mystery
of how we appeared on the Earth.

Apes evolved bigger brains to be better
fighters.

and in so doing became human.

The engine of our evolution was violent.

And more australopithecine discoveries
made it possible to compare their

to ours.

The human pelvis is very different from
the pelvis of any other mammal.

It's very short. It's very squat.

You can see this by looking at the ape
pelvis, where the hip bones are very

and very flat from front to back.

Now, the first ever discovered
australopithecine pelvis.

was really quite a surprise because it's
very human -like in form.

And this can be seen clearly if you
compare it to a modern human bone from

individual about the same size.

Now, the reason this is important is
that this pelvic shape has everything to

with the fundamental human
characteristic of being able to walk on

So what we can tell about the
Australopithecines... is that although

ape -like in many features, they were
able to walk on two legs.

And because of this, we know that they
must have played a very important part

the human story.

Just as Dart first suspected, the
Australopithecine did indeed walk

unlike any mammal except us.

These creatures could now be confirmed
as the first human ancestors.

But scientists had little more than a
few isolated fossil bones, not enough

an accurate picture of the
Australopithecines.

And then, in the Hadar Mountains of
southern Ethiopia, a complete skeleton

unearthed.

A team of fossil hunters located the
remains of what must be the most famous

Australopithecine of all, a creature
they called Lucy.

Most of the specimens that one finds are
early hominins.

are just very small scraps.

But occasionally fortune smiles on you
and you discover something remarkable

like Lucy, a little more than three
million years old.

And the chances of that happening are
probably like those of winning the

lottery.

At first, scientists expected that a
complete australopithecine skeleton

display further human -like features.

But Lucy's bones revealed something very
different.

Lucy was quite small, not much more than
a metre in height.

My finger bone is really quite straight.

Lucy's is curved, and the only good
reason to have a curved finger bone like

that is that you're clasping something,
and the thing that they're liable.

able to clasp with a branch.

And if you're clasping branches, you
must be living in trees.

Lucy could have walked, but certainly
was also very at home in the trees, or

a cliff, or on a rocky outcrop.

When you take these little rib
fragments,

And you assemble them. They don't make
up a rib cage, a human sort of rib cage.

They make up a chimpanzee sort of rib
cage, which is narrow at the top and

at the base.

And that's the sort of rib cage you have
if you have a large gut.

And the reason that you have a large gut
is that your diet has a lot of

vegetable matter in, and you need the
gut in order to digest it.

And we now realize that the sorts of
changes that you would need to make from

Lucy -type animal into a human -type
animal are quite profound.

They were not like apes in a few
important ways, but in many ways they

apes.

Small, plant -eating tree -dwellers.
Although upright like us, Lucy's

showed that the first Australopithecine
ancestors were in every other way still

apes. This makes them no less
interesting.

In fact, it makes them in many ways more
interesting because we now have to see

them as animals in their own right.

Three million years ago, caves like this
gave shelter to the Australopithecines.

But the true nature of our small,
upright ancestors was being transformed

discoveries.

Dart was convinced that our early
ancestors were brutal predators.

This primitive hyena, Joe, could rip up
a belly.

He wrote about these killer apes flaking
their ravenous thirst on the hot blood

of victims and greedily devouring livid,
writhing flesh.

For him, the fossil record contained
proof of our violent origins.

Part of Dart's theory was that because
one only found the skulls, parts of the

skulls generally, of the ape men and of
the baboons,

This, to him, meant that our ancestors
had been headhunters and professional

decapitators, as he put it.

But Bob Brain wondered if there might be
another explanation for the high number

of skulls the archaeologists were
finding.

When baboons and people are eaten by
leopards, frequently the

whole skeleton disappears and all that
remains is parts of the skull.

And when he looked at the fossilised
australopithecine skulls, his instincts

were confirmed.

One of the most important bits of
evidence that made me suspect that

Dart was perhaps wrong in claiming that
we had been the predators, the killer

apes, was this skull of a child from
Swartkrans.

We're looking here at the back of the
skull, the two parietal bones, and these

have two round holes in them.

And then...

From the same part of the cave,
interestingly enough, we had the lower

mandible of a fossil leopard, the same
species as we have today.

And we found that the spacing of the
lower canines of this leopard matched

almost exactly the spacing of these two
holes in the back of this unfortunate

child's skull.

This made me conclude that we were the
hunted, not the hunters.

vulnerable ape at the mercy of
predators.

The more the archaeologists discovered
of Taung child's kind, the harder it was

to explain how they could have been
successful enough to be our ancestors.

But these delicate creatures were not on
their own.

Some of the Australopithecines are like
the tongue child.

They're very lightly built, and they're
gracile in their form. In fact, we call

them gracile Australopithecines.

Then a strange new species of ape man
began to emerge from the ground.

Other Australopithecines were very
different.

They had extremely big cheek teeth, very
heavily built jaws.

They also had very heavily built faces
and they had this strange crest that

down the center of the skull.

We call these Australopithecines the
robust Australopithecines.

The robust and the gracile had both
evolved from our earliest ape ancestors.

Something in prehistoric Africa was
changing.

The pace of evolution suddenly
accelerated, and the Australopithecines

split into two disconnected forms.

Why?

At Makapansgat, in the same caves where
Raymond Dart thought he had found the

killer ape, archaeologist Kay Reid has
come to look for clues to explain this

bizarre mutation in the
Australopithecine lion.

Channeling deep into the rock, her team
has reached a level in the cave floor

which is three million years old.

Exactly the same period the
Australopithecines began to divide into

gracile forms.

What Kay Reid has found are not the
remains of human ancestors, but the

bones of antelope.

What you can see up here, are a lot of
fossil antelopes that are about three

million years old these particular
antelopes are adapted to an environment

that's pretty wooded and lush and clues
to the prehistoric climate

come from the teeth of these long
extinct antelope these teeth indicate

there was a browsing animal it ate
leaves sometime during this period this

particular antelope became extinct it
couldn't survive its diet disappeared

you get new antelope appearing with
teeth like this that are designed for

grass so there's a big turnover at this
time where these grazing animals replace

these browsing antelopes a dramatic
climate change transformed the dark

forest to dry scrublands and savannah
three million years ago A change that

also have affected the lives of the
Australopithecine.

This is the same situation that our
early ancestors faced.

And they either had to adapt or become
extinct.

The Australopithecines' new environment
would have been very like the African

scrublands of today, harsh, dry, and
with few obvious choices of food.

And here, Kay Reid has looked for
evidence to see what the

might have done to survive.

The only potable food sources are thick
roots and tubers.

This may look like it's not very good
food, but in fact it's where most of the

nutrition in the plant resides. And
because of the environment that these

australopithecines are found in, I have
a feeling that this is the type of food

they were eating.

This new diet holds the key to the
robot's strange appearance, the great

skull crest.

The crest is for the attachment of the
big jaw muscles that help to move the

jaw. And undoubtedly, they were able to
generate really large forces between

those shaped teeth.

We think that they must have eaten a
diet that required extremely heavy

The three -million -year -old creature
at Sterkfontein has the powerful jaws of

a robust Australopithecine.

And what's remarkable about it is the
massiveness of the cheekbones in this

region here.

It seems to have the trace of a crest on
the top of the skull, indicating very

powerful jaw muscles.

But if the mighty robot could only
survive climate change by chewing plant

roots, what would the puny, vulnerable
greyfowl find to eat?

Then researchers at New York State
University made a remarkable discovery.

By coating the inside of
Australopithecine skulls with liquid

series of artificial brain casts,
perfect replicas of these prehistoric

From the shape of these casts, they saw
instantly that our bigger brain could

only have evolved from a gracile
ancestor.

Archaeologists began to wonder if the
changes that led to a bigger brain might

have been caused by a change in diet.

What we know by looking at the animals
on the African savannah is that

vegetarians don't have big brains.

Archaeologist Tom Loy has begun to find
answers in a peculiar collection of

stones. found alongside
australopithecine remains.

Until two years ago, many of them, this
one for example, were simply thought

to be just a waste bit of rock.

Wondering if there might be more to
them, Tom Loy examined the small stones

closer detail.

I've used...

a very high -power microscope, and some
biochemical tests, and established that

this part here has bone working. This
has got blood and meat tissue.

There's some hair in there.

Millions of years ago, these fragments
of stone were covered in blood and

tissue.

and more than a thousand miles up the
Great African Rift Valley.

Another team is also searching Graythar
remains for evidence of what triggered

their brain growth.

Here at Olduvai, they have uncovered a

hoard of animal bones.

At the field lab, Rob Blumenshine has
been examining the finds.

At first sight, the bones seem to have
been chewed by the carnivorous savannah

predators.

This specimen shows conspicuous tooth
marking by a large carnivore. Yet,

looking more closely, one can detect a
very faint striation on the

surface of the bone.

Cut marks like these are made from
stones.

Stones identical to those found by Tom
Loy.

This specimen is an arm bone of an
antelope, and it preserves a small

mark on this fracture edge, which was
produced when hominids rested the bone

an anvil and used a hammer stone to
break open the cavity, exposing the fat

-rich marrow inside.

Subsequently, the bone was chewed by a
carnivore.

Here in these fossilized bones is proof
that the

gracile Australopithecines had
discovered the first stone tools and

these tools on the bones of animals.

While their robust cousins were eating
tubers, The Greysauce had found meat.

For Leslie Aiello, this was a hugely
significant step.

Meat would have been very important to
our early ancestors because meat is

energy food and it's easy to digest.

Now this is important because it would
allow us to have very small digestive

systems, very small gut.

Professor Aiello believed that a smaller
gut would have had an impact on the

brain.

Guts are very expensive in energy terms.
So the smaller the guts you have, the

more energy you have for a larger brain.

But how could the tiny grey cells
compete successfully for meat with the

predators of the African savannah?

Dark man lying with fairly full belly.

Doesn't look like he ate last night.

The extinct volcano of the Ngorongoro is
home to just the kind of predators that

would once have faced the
Australopithecines.

It's clear from a place like the crater,
which is very open without many trees,

that although there is a tremendous
amount of scavengeable food available,

would not have been accessible to our
ancestors without them incurring

tremendous risk themselves from
predation.

As well as its predators, the African
savannah is also home to some of

most efficient scavengers.

Hyenas are very abundant in these open
environments and get to carcasses

and thoroughly consume them, leaving
nothing for a would -be hominid

Unable to compete on any front, the
Australopithecines needed to find meat

no one else wanted it.

This is a partial cranium of a
wildebeest that died some time ago. The

has been heavily ravaged by scavengers
who dispersed all of the edible parts

over the landscape. Yet, even in this
heavily ravaged carcass, we see that the

cranial case is intact.

the brain would have been available,
providing about 300 grams of protein and

fat. And had the carcass been less
ravaged, and, for example, the leg bones

present, when fresh, this would have
indeed provided hominids with a very

substantial meal of brains and marrow.

They could crack through the bone with
their primitive stone tools.

And when they got to the bone marrow,
they would have a very rich fatty food

that would give them higher energy, but
also give them the building blocks for

the growth of the brain.

With tools to get at bone marrow.

The Greysiles now began a great journey
that would take them far away from their

ape origins.

Experiments show archaeologists how
difficult in practice it would have been

the gray sows to make their first stone
tools.

But it was just this difficulty that
made all the difference.

In the struggle to survive, Those gray
cells who were intelligent enough to

tools would have had an advantage over
those that couldn't.

Bad tool makers would die off and good
ones would reproduce.

Here at last was exactly the kind of
evolutionary mechanism that

had been searching for.

There is a very interesting feedback
mechanism associated with it.

We have tools, we have meat, and we have
large brain sizes.

And you can't have one without the
other.

Stone tools would have allowed them
access to this high energy food

access to the meat.

And in turn, the meat would be necessary
for the growth of the large brain.

So the larger brain and the more
intelligent they were, the more

were in making tools, the more efficient
they were in being able to extract the

meat that they needed to eat. So you had
the system feeding back on itself.

Once the dietary change occurred,
because of the interrelationship of tool

and brain size, the stage was really set
for human evolution.

Taung Child, the first Australopithecine
to be discovered, belonged to a species

existing at the deepest root of the
human family tree.

A group of ape -like creatures who, with
tools and meat, had begun the long

process of developing human -like
brains, but who were still very much

at the mercy of nature.

Always been a very strange and curious
problem.

Why only a single specimen came from
here?

Why were there not others? Why did we
not have the child's parents?

It was a problem how this child came to
be alone here in the cave.

The very likely solution to the mystery
has now been presented to us, and it

explains the curious feature of an
indented or depressed fracture

which had worried me for years and
years. How did that come about? It's

just the sort of scar that one might
expect

from the great killing talon.

of an eagle.

The child was carried away to a lonely
death at Taung.

But enough of its kind managed to
survive on the African savannah and

brains large enough to allow them to
embark on the next phase of the human

story.

In the next episode, we will witness the
first emergence of our human form.

In the body of a boy who died a million
and a half years ago.