Missing Links....Homo Erectus (1080 HD)

>> Over a million years ago,

in remote caves in
China and Indonesia,

our prehistoric
ancestors mastered fire,

shaped stone tools, and faced

ferocious predators such
as saber-tooth cave lions.

Until recently, these
ancient Asians were

thought to have
become a dead end

branch of this human tree.

Now, controversial
theories are disputing

the conventional picture of

modern man's origins in Africa.

Thirty miles South of Beijing,

in China's most famous
archaeological site,

Zhoukoudian or Dragon Bone Hill.

In this cave, dozens of

extraordinary skulls and
bones have been unearthed,

dating back a million
years to a time

when our ancestors were
not yet fully human.

Scientists call them Homo
erectus, upright man.

Although Homo erectus has

also been found in
Africa and Europe,

anthropologists have
fiercely debated

for almost a century where

these early Asians
came from and whether

they belong on a
modern family tree.

But they do know what
Homo erectors looked

like based on the skulls
that have been found.

Their eyes were set far apart
under a massive brow ridge.

Attached to the brow were

thick muscles for chewing which
moved the formidable jaw.

The size of the
jaw and the teeth,

25% bigger than our own,

revealed that Homo erectus

probably relied
on their teeth as

tools to grip and pull
objects such as animal hides.

Simple stone tools showed

that Homo erectus was
also intelligent.

The skulls vary
enormously in size,

falling in the range
of humans today.

What ideas were kindled in

the mind of these rugged
looking forebears?

What world did they face in

the China of half a
million years ago?

Back then, much of
the Earth's climate

was colder and drier.

The seas dropped
by up to 300 feet,

exposing land bridges
like the Sunda Shelf

that link the Indonesian
islands to mainland Asia.

Much of Southern Asia was
covered in tropical rainforest.

The discovery of extinct
elephants throughout

Indonesia indicate they were

open areas where large
animals could graze.

Stone tools found
with Homo erectus,

suggest he was a hunter

and would have been
attracted to big game.

We face stiff competition.

Not only were there
elephants, bears, leopards,

tigers, and rhinos, but
also saber toothed cats.

Ferocious cave lions with

huge teeth used to
tear its prey apart.

Many erectus bones from

Asian cave sites
bear gnawing marks,

suggesting their owners
were dragged to the cave

as victims of these
fierce predators.

But where did these
primitive humans come from?

Did they originate in Asia

or migrate from somewhere else?

The trail of clues
began in Indonesia,

where the very first skull of

Homo erectus was found

by an adventurous
Dutch anatomist,

Eugene Dubois, back in 1891.

Prospecting for fossils along

the banks of Javas Solo river,

Dubois unearthed a
thick skull cap,

which he was convinced
belonged to a primitive human.

At first, his finds
were ridiculed,

so he hid the bones under

the floor boards of
his home in Holland.

In 1936, German anthropologist,

Karl von Braun-Fernwald,

visited Dubois in Holland,

examined the fossils and
decided they were authentic.

Karl von Braun-Fernwald,

returned to Java
the following year,

determined to find
a well preserved

Homo erectus skull,
and he succeeded.

This time, nobody doubted
that this rugged skull with

its beetle brows and

massive jaw belonged on
the human family tree.

Other skulls eventually
surfaced in Europe and Africa.

The most spectacular was on

the shore of Kenya's
Lake Turkana.

On a broiling August
afternoon in 1984,

renowned fossil hunter
Kamoya Kimeu was

out prospecting when he

spotted a dark brown
fragment of skull.

It took five years
for a digging team to

unearth one tiny
fragment after another.

But eventually, they
assembled a unique find,

a nearly complete Homo
erectus skeleton.

Dubbed Turkana Boy,

he stood about five
feet four inches tall.

Yet surprisingly
he was still only

12-years-old when he died.

The boy's tall athletic
build is significant,

according to leading Homo

erectus scholar,
Philip Breitmeyer.

>> That particular boy weighed

perhaps 68 kilos if he
had been able to grow up.

That's 150 pounds,

perhaps a good round average for

early Homo erectus
in East Africa

was closer to 58 kilos
or about 130 pounds.

They were tall people also,

certainly quite comparable in

those respects to us
to modern humans.

Large body size would have

conferred an advantage
on Homo erectus,

and that larger people are

simply able to cover
more territory.

Larger primates,

larger mammals in
comparison to smaller ones,

usually behave that way.

Simply cover more territory
and search of food.

It's likely that Homo
erectus was also engaging in

more hunting and consuming

more meat than its
predecessors had done.

Meat is a highly caloric food,

Homo erectus would have been

able to meet its energy needs

much more efficiently if it were

doing some hunting on a regular,

more systematic basis than
had been done before.

>> Archaeologists
think Homo erectus ate

more meat because they
found the first well made

stone tools ideal for butchering

meat at erectus sites in Africa.

Once early humans
knew how to make

efficient tools and learned
how to control fire,

they were ready to leave
their African cradle

and colonize the
rest of the world,

or so archaeologists
have always assumed.

The conventional view is that

Homo erectus originated in
Africa two million years ago.

They were the first humans
to leave the continent,

spreading gradually into

the Middle East,
Europe, and Asia.

But in 1994,

a stunning series of discoveries
through these old ideas

opened a question that raised

a dramatic new possibility
about Asia's earliest humans.

The history of Asia's
earliest humans

first emerged at the
Zhoukoudian caves,

near Beijing in the 1920s.

Here emerged the
fossils that quickly

became celebrated as Peking Man,

even though many of the bones

actually belonged to
women and children.

Archaeologist Russell Chauhan

specializes in Asian prehistory.

>> When the first skull of

Peking Man was
discovered in 1929,

it generated banner headlines

in newspapers around the world.

Because for the
first time we had

truly early man in China.

Earlier finds had
been made in Java,

but this was far North.

This was in a cave context,

and this also contained

artifactual evidence,
stone tools.

None of those events happened
with the finds in Java.

This is what made this
site so significant.

>> One discovery created
a special sensation,

the evidence that
they had used fire.

>> Thick ash layers at
the site of Zhoukoudian

indicate that Peking Man had
developed the use of fire.

The use of fire was

an important cultural
hallmark in human evolution.

It allowed the exploitation
of temperate environments.

The use of fire together
with a varied tool kit,

made up of hammerstones,
choppers, points,

and scrapers, allowed
Peking Man to live in

a much colder environment
than any Homo had had before.

>> Another sensation was

created by the theory
that the bones

found in the caves were the
result of cannibal feasts.

>> The idea of cannibalism
at Zhoukoudian was first

proposed by the famous
German anatomist

Franz Weidenreich in 1940.

Weidenreich couldn't
explain how the bones

of Peking Man had
gotten into the cave.

In addition, upon
studying those remains,

he also was puzzled by
the fact that there was

a disportionate number of

skull remains to
limb bone remains.

He came up with the idea that

cannibalism was responsible
for this occurrence.

Today, we know there are

natural occurring agents that

could have brought the
bones into the cave,

such as porcupines, or

large carnivores that
made layers in caves.

We can also analyze the bones

of Peking Man for cut marks,

which would have been present

if cannibalism had occurred.

The issue of cannibalism and

Peking Man at
Zhoukoudian is now dead.

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>> Digging at Zhoukoudian
continued for

over a decade from the
1920s to the 1930s.

When the Japanese invaded China,

the digs director
Franz Weidenreich,

decided he would leave

for America and take
the fossils with him.

The fossils arrived at the port

serving Beijing on December 7th,

1941, today, the Japanese
bombed Pearl Harbor.

Casualties of war, the fossils
mysteriously vanished.

They were never seen again.

But Weidenreich had
the foreside to make

plaster casts which
survived, 14 skulls,

15 lower jaws, and more
than 200 isolated teeth,

along with over 100,000
simple stone tools.

>> We have an extensive
cultural record,

consisting of scrapers,
such as this one here,

which was likely used to scrape
out the inside of hides,

and choppers, such
as this one here,

which was used for digging.

All of these
cultural remains and

fossil remains occur throughout

the deposits at Zhoukoudian.

Dates of these deposits now

indicate that Homo
erectus spanned

the time range
from 400,000 years

ago to 700,000 years ago
at this important site.

>> Important as the
Zhoukoudian fossils are,

they are not the oldest Homo

erectus fossils
ever found in Asia.

The quest to discover
an older site led

Russell Chauhan and his
Chinese colleagues to

organize an expedition in

1991 to a remote part
of Sichuan Province.

Probing a rocky hillside
overlooking the Yangtze River,

the team began digging inside

an ancient collapsed cavern,

known as the Longyou Cave.

Eventually, they
unearthed stone tools,

extinct animal bones, and the
lower half of a human jaw.

Recently, these finds
were dated to a

staggering 1.9 million years,

as old as the earliest known

Homo erectus finds in Africa.

Then in 1994, bones from

Java triggered headlines
around the world.

One skull from Java proved
to be 1,750,000 years old.

While the others were both
over a million and a half.

Again, the implications
were shocking.

Erectus in Indonesia was as

ancient as any
erectus in Africa.

These discoveries led Chauhan
to a radical new theory.

>> Now, what does this mean?

If we want to take it
in the perspective

of these different hypothesis,

we might argue that
Homo erectus could have

evolved in Asia and
spread back in Africa,

in a sense, which
would challenge

all the conventional
wisdom on the subject.

By this, I mean, maybe
the ancestor of erectus

spread out of Africa

two and a half million years ago

populated the rest
of the old world,

and then was subsequently

reintroduced back
into Africa at 1.7.

This is a rather
radical interpretation,

but it is certainly

a plausible one given
the new dates in Asia.

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>> In fact, the new
Asian dates star

up many provocative
theories and questions.

If Homo erectus reached

China nearly two
million years ago,

did they evolve into
us, Homo sapiens?

Or was erectus in Asia

a dead end and replaced by a
second wave out of Africa?

This time, fully modern people,

the ancestors of China's
present population,

led to one of archaeology's
fiercest debates.

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>> Half a million years ago,

Homo erectus lived
in these caves near

Beijing sharing the
valley below with deer,

horses, elephants,
and cave lions.

Today, fossil casts of

so-called peaking man are kept
in the local museum where

anthropologist Russell
Choukoutien compares

the skulls of these
ancient humans to our own.

>> Here in front of us, we have

a typical skull of Homo
Erectus from Choukoutien.

You can see features
that are distinctive.

It has a very
projecting brow ridge.

The forehead slopes
quite severely back,

and it has a nucle
crest at the back.

The skull is also flattened,

where it is wider at the
base and narrow at the top.

These features are in

striking contrast to what
we see in modern humans.

In addition to the morphological
features of the skull,

it has a brain size
or cranial capacity,

roughly two-thirds of
that of modern humans.

>> At first glance,

one is struck by Peking
man's primitive appearance.

His thick brow ridges
and massive jaw

indicates that he
still relied on

his teeth, not refined tools.

Can it really be true that

Homo erectus belongs
to our family tree?

It's a tantalizing question,

and the evidence of Choukoutien
reinforces the mystery.

At one of the caves,
skulls were found

dating to relatively
recent times,

just 30,000 years ago.

The bones belong
to ice age hunters

who probably spent the winter
sheltering in the caves.

Are they the direct
descendants of

Peking Man and the ancestors
of the modern Chinese?

[BACKGROUND] Physically
identical to modern humans,

they were definitely
Homo sapiens.

But did another human branch
leave Africa a second

time and lead to the population
we see in Asia today?

In the 1980s, an
ingenious technique was

developed to trace
the genetic history

of the world's populations.

It involves sampling
the genetic material

known as mitochondrial DNA,

passed down only through
the female line.

The results showed
that all modern humans

are descended from
an ancestral Eve,

a hypothetical mother of us
all, who lived in Africa,

some 200,000-100,000 years ago.

The theory caused a sensation.

Recently major flaws were
exposed in the DNA Eve theory.

Yet archaeologists such
as Philip Witmeier,

are still convinced that
the fossil evidence

can only be explained by

a great migration of
modern humans out

of Africa 100,000 years ago.

>> Certainly, some of the
best evidence as far as

modern human origins
are concerned,

comes from Africa, particularly

from the southern
part of Africa.

I have in mind a cave called

Klasies River Mouth on the
coast of South Africa.

Klasies has yielded a
number of human fragments.

Unfortunately, the bones
are rather badly broken up.

There are mandibles with teeth,

bits of face, bits
of skull vaults,

and limb bones, also.

These materials,
insofar as we can check

them are essentially
modern in their anatomy,

hardly distinct from ourselves.

The important point
here concerns the age.

Klasies has been well-dated at

this point through a number
of lines of evidence.

The first occupation at
Klasies River Mouth dates

right back to more than
100,000 years ago.

People were resident in the
cave for a time after that.

This to my mind, constitutes

some of the strongest evidence

we have pointing to an African
origin for modern people.

>> Witmeier and others think
that modern humans spread

out of Africa 100,000 years ago

and that their
superior intelligence

and technology drove
the erectus and

its descendants in Europe
and Asia into Oblivion.

But these two
researchers disagree.

Milford Wolpoff, of

the University of Michigan
and Alan Thorne of

Australia National University
are longtime collaborators.

For years, they've taken
a maverick position

on the origin of modern humans.

They deny the conventional
out-of-Africa

theory and argue that modern
Asians evolved in a smooth,

unbroken line from
their ancient roots.

>> Now, all of this
took place with

evolution that was
within East Asia.

There's no evidence at all

of some new set of people coming

in and replacing this whole
sequence or even changing it.

It is continuous.

It comes up to people in Java,

who've got brain cases that
are in the modern range.

These people are just
as smart as you or me,

on into Australia and
on into modern people,

and in East Asia,
the same thing.

Now it's a continuous evolution.

It's not broken.

Once people leave Africa,

we don't need a second
movement out of Africa.

These people are evolving
to modernity all by

themselves in the sense

that there's a local
regional group.

Of course, they're in contact

with the rest of
the human world,

but we don't need
anybody to replace

them because they're heading

in the modern direction anyway.

That's regional continuity.

Put this into several
places in East Asia,

South East Asia, Europe,

and in Africa, and you've got
multi-regional evolution.

>> Thorns collaborator,
Milford Wolpoff claims

that the evidence from China is

particularly strong
in their favor.

>> Here's the earliest specimen
we know of from China.

It's more than a
million years old

from a site called Lanthium.

It's a upper jaw right here
just like I'm showing on

my face teeth and
a piece of cheek.

What you can see here,
if you look carefully,

is that the face is flat,

the teeth and the
crest is flat with

the cheek comes off of the face,

and it's very anterior,

very much like a
Chinese of today.

We can find that
same characteristic

here in this woman from

Joco Chan at about half the
age, about 500,000 years.

What this shows is that

the roots of the modern
North Asians are

found in people living in

Asia as long ago as
a million years.

>> But many, including Witmeier,

disagree with
Wolpoff's view that

the ancient fossil skulls have

characteristics resembling
modern Asian faces today.

>> There are a number of such
characters which are cited

in support of regional
continuity in China.

The problem is that a number
of these characters are

distributed into
other populations

spread all across the old world.

They are not limited
to the Far East,

certainly not just to China.

The flattening of the
nasal saddle, for example,

actually reached their
highest frequencies

in African populations,

well outside of the Far East.

Here again, there's a pattern,

but it's not the pattern
that one would expect to

find in support of
regional continuity.

>> For Witmeier, the
fossil bone suggests that

Homo erectus in China
became isolated,

a dead end outside the
mainstream of human evolution,

an archaic form of
human swept aside

by the spread of modern man
during the last Ice Age.

With so few fossils discovered

over such an immense
span of time,

it's not surprising
the experts can build

conflicting visions
of our human past.

>> This is all Homo sapiens.

I don't think we need
Homo erectus anymore,

and it would help us to see

our evolution if we call
them all Homo erectus.

For me, only one species of
human ever leaves Africa,

and that's us.
That's Homo sapiens.

>> I'd be quite happy to get

rid of the name Homo erectus.

It now has become a name that

doesn't have anything that
it clearly refers to.

The fact is is that once humans

appeared as Homo sapiens,

they've been human ever since,

and I think we can show
that by calling them Homo

sapiens from the very beginning

some two million years ago.

>> If Wolpoff and
Thorn are right,

it's extraordinary
to think we can

trace our origins
back directly to

those primitive-looking
cave dwellers

who had to contend
with saber tooth cats.

If they're wrong and the
ancient cave dwellers

were replaced by a second
wave of humans from Africa,

then Homo erectus
went the way of

the saber tooth cats,
pushed into extinction.

After they had survived
resourcefully,

generation after generation
for millions of years.

Whichever theory turns
out to be correct,

both represent a powerful
evolutionary drama

buried in our
distant human past.

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