Original subtitles

WILLIAM SHATNER: Shocking discoveries

revealing glimpses of mankind's ancient past,

the bones of giants that lived centuries ago

and primitive beast men

roaming the wilderness.

Of all the mysteries

that mankind has been able to solve,

one still baffles our collective curiosity.

Where did we come from?

Were human beings the result of a spontaneous,

divine creation?

divine creation? Or is it possible

Or is it possible

that we, as some evidence suggests,

evolved over time from other species?

And was there possibly a missing link

that made us what we are today?

Well, that is what we'll try and find out.

♪ ♪

(creatures chittering)

SHATNER: Since the dawn of man, human beings have wondered

how we came into existence.

how we came into existence. And throughout history,

And throughout history,

people have proposed many different theories

to try and explain the profound mystery of mankind's origins.

Since the earliest written records, it's clear

that human cultures around the world

that human cultures around the world have been curious about our origins.

have been curious about our origins.

Where did we come from? It's a great question.

And the question means something different to everyone.

Every culture has different origin stories.

Every culture has different origin stories. In many creation stories about human origins,

In many creation stories about human origins,

humans are fully formed from the start.

For example, in Genesis chapter one

of the Hebrew Bible, we get a very structured,

very orderly account of creation.

In this narrative,

through a series of spoken acts,

through a series of spoken acts, God creates the heavens, the Earth,

God creates the heavens, the Earth,

creates land, the seas,

and then populates all of these domains

with fish and birds and creeping things.

And then, on day six,

And then, on day six, God creates the humans.

God creates the humans.

And Genesis records that God

speaks the humans into existence,

male and female, in His own image and likeness.

The implication here is that these humans would look

just like we look today.

MICHIO KAKU: Throughout history, before the coming of science,

all we had were mythologies about our origins.

Stories, tales handed down generation by generation

Stories, tales handed down generation by generation over thousands of years.

over thousands of years.

That's all we had.

But then we had Charles Darwin,

and Charles Darwin said that we are related to the apes.

and Charles Darwin said that we are related to the apes. And that was a huge shock.

And that was a huge shock.

SHATNER: In 1871, Charles Darwin published

The Descent of Man, which proposed the theory

that humans and apes share a common ancestor.

SHAPIRO: The natural evolutionary history of our lineage

is that we were monkeys and then we were apes

and then, eventually, we became Homo sapiens.

But when and how this happened, it's still something

that scientists are trying to piece together

from the often fragmentary fossil record.

SHATNER: Ever since Darwin's groundbreaking work,

many have theorized that there could have been

many have theorized that there could have been a so-called "missing link"

a so-called "missing link"

between us and our primitive ancestors

that would explain how modern humans came to be.

But in recent years, scientists have suggested

that this idea may be too simplistic,

and that the truth about mankind's origins

is far more complicated and mysterious.

KIRSTEN FISHER: I think our idea that there might be

a missing link in human evolution

stems from the way humans

may be inherently uncomfortable with the idea

that evolution doesn't... hasn't progressed towards us

on purpose or with any particular direction in mind.

In the relative scheme of things,

In the relative scheme of things, we're just a very small branch

we're just a very small branch

in a much more diverse tree of living things.

Which is kind of an amazing thought.

Human evolution in the past

has been seen as a sort of line.

has been seen as a sort of line. You see that sort of typical,

You see that sort of typical,

uh, an ape hunched over and slowly standing up.

But we're now realizing that it's not true.

In our past, there were multiple different species

that actually had similar traits to modern-day humans.

that actually had similar traits to modern-day humans. And so, evolution is not linear.

And so, evolution is not linear.

It's not even a tree, it's more of like a-a brambly bush.

It's all over the place.

SHATNER: Could it be that there is not one missing link

but rather many different species

that formed the human evolutionary tree?

And if so, could they have had a significant effect

And if so, could they have had a significant effect on the origins of mankind?

on the origins of mankind?

To answer that question, perhaps we should begin

by examining the species we're most closely related to,

by examining the species we're most closely related to, the Neanderthals.

the Neanderthals.

Genetics company 23andMe announces

their at-home testing kits can now detect

how much of a person's DNA comes from the Neanderthals.

Neanderthals are an extinct species

that were very similar to humans

and died out roughly 30,000 years ago.

But the 23andMe tests have shown that there is a small percentage

of Neanderthal DNA in each and every one of us.

REAGAN: With the advent of these designer DNA tests,

it's making us rethink the way humans evolved.

Neanderthals are a subspecies of Homo sapiens.

We share a common ancestor with them

around 800, 700,000 years ago.

They existed in what is Europe, the Middle East,

and basically dominated the ice age.

And hopefully, now that we know

that we have Neanderthal DNA in our genome,

we'll be more interested in actually learning

about our past.

KAKU: This is a shock, 'cause we used to think

that we didn't mate with anybody else.

But using the science of DNA,

we begin to realize, "Hey, there was a lot of mating

that went back and forth between Neanderthals and humans."

We now have data to work with

to retrace the family tree of our race.

SHATNER: Modern humans

and Neanderthals are both what scientists refer to as hominins,

a group of species that includes mankind

and its closest relatives.

Thus far, fossils of 21 different hominin species

have been found, and new genetic discoveries

are revealing that we have much more in common

with the Neanderthals and other hominins

with the Neanderthals and other hominins than previously thought.

than previously thought.

ANDREW COLLINS: Neanderthal fossils

first came to light in the early part of the 19th century.

But at that time, they were dismissed as inferior to us.

So the idea that modern humans have Neanderthal DNA in them

is incredibly important,

because it shows that they are our distant cousins.

We're realizing now, more and more,

that they were, in every respect, human.

If you had a Neanderthal today and you dressed them in a suit,

would you know it was a Neanderthal?

The answer is probably you wouldn't.

They were great, uh, toolmakers and users.

They left behind art.

Different jewelry as well.

Different jewelry as well. We're finding out that Neanderthals

We're finding out that Neanderthals

We're finding out that Neanderthals were actually burying their dead,

were actually burying their dead,

which shows that they were invested in their loved ones.

What we've learned by studying Neanderthal DNA

is that some traits that Neanderthals had

were passed into modern human populations.

One of the traits that came from Neanderthals

was a propensity to have diabetes.

And so it ended up getting passed on,

even though it provided a little bit of a disadvantage

to those who had it.

Our closest relative is the Neanderthal,

and they're gone, but they also survive in our DNA.

and they're gone, but they also survive in our DNA. The more we can learn about them,

The more we can learn about them,

the more we learn about us.

Did the Neanderthals play an important role

Did the Neanderthals play an important role in the evolution of modern humans?

in the evolution of modern humans?

in the evolution of modern humans? Or could it be that they only represent

Or could it be that they only represent

one piece of the puzzle?

Because recently, scientists unearthed the bones

of another ancient species, in Asia,

that may have played a role in our development.

A species that was never known to exist.

SHATNER: Archaeologists conducting excavations

within the dark recesses of the Liang Bua cave

uncover the skeletal remains of a primitive human.

Oddly, the bones appear to belong to an adult

Oddly, the bones appear to belong to an adult less than four feet tall.

less than four feet tall.

And genetic analysis reveals that the person's short stature

was not due to deformity.

Remarkably, this individual belonged

to a previously unknown species

of miniature humans

that lived 60,000 years ago.

TOCHERI: The team of scientists excavating on Flores

uncovered the partial skeleton which we now know as LB-1,

or Liang Bua One.

It immediately sent shockwaves around the world.

We know it's a member of our genus Homo

because it has characteristics of its teeth and jaws

because it has characteristics of its teeth and jaws that we use to define our genus.

that we use to define our genus.

So it's these features that help us understand

that it is closely related to us, but smaller.

SHATNER: After further study, the newly discovered species

of miniature humans was given the name Homo floresiensis,

after the isle of Flores on which it was discovered.

The $64 million question is how did the ancestors

of Homo floresiensis reach Flores?

Flores is a oceanic island.

That means it's never been connected by land

to either the Asian continent or the Australian continent.

It's long been thought that only modern humans

were clever enough to somehow reach these kinds of islands

by crossing open water.

And so, to find Homo floresiensis

on this oceanic island

shows us how much we underestimate

earlier hominins in terms of their dispersal capabilities.

JIM VIEIRA: What's most interesting is they found tools

on the isle Flores.

Finding tools on this isolated Indonesian island

opens up a Pandora's box of ideas.

How did they get there,

how far back do these beings exist

and what level of sophistication did they have?

TOCHERI: Homo floresiensis disappears

roughly about 50,000 years ago.

But we only have evidence from this one cave.

And so, I think there's still a lot that we need to uncover,

to figure out the most likely explanation

for their extinction.

SHATNER: Due to their stature,

some anthropologists began calling Homo floresiensis

"the hobbits," in reference to the furry-footed characters

from Middle-earth popularized by author J.R.R. Tolkien

in his 1937 book The Hobbit,

which has led many to wonder, could hobbit-sized humans

be part of a missing link?

The hobbit is the prime example of saying, "Hang on, stop,

and start thinking of what's going on here."

As time goes, we're finding more and more evidence

that there was a range of different kinds of humans.

KAKU: In science,

we always have to keep an open mind,

we always have to keep an open mind, even when things, uh, disturb

even when things, uh, disturb

our sense of who we are and where we came from.

We're just beginning to realize that The Lord of the Rings

is really a paradigm for other species out there,

is really a paradigm for other species out there, lurking, that have not yet been discovered.

lurking, that have not yet been discovered.

Homo sapiens are not necessarily

the only game in town.

SHATNER: The discovery of Homo floresiensis

proves that humans were just one of many intelligent species

to inhabit Earth in the past.

But remarkably, there could be evidence

But remarkably, there could be evidence of not only hobbit-sized humans

of not only hobbit-sized humans

but also a species of giants that once lived

in what is now modern Russia.

The Altai Mountains, Siberia.

Archaeologists conducting excavations inside a cave

make an unexpected discovery.

They find two enormous human teeth,

twice the size of a modern person's.

What they found was some massive teeth that were so big

they thought they were cave bear teeth.

But then, they were sequenced, and they realized

it's a new human cousin who may have been seven,

eight foot tall, with massive skulls and jaws.

It's really a curveball to anthropology.

SHATNER: Further analysis of the teeth

revealed they were more than 50,000 years old,

and belonged to a previously unknown human subspecies

that has been named the Denisovans.

From what little evidence of the bones and the teeth

From what little evidence of the bones and the teeth that have been found,

that have been found,

not only at the Denisova Cave in Siberia...

...but also a huge jawbone

that was found in a cave on the Tibetan Plateau,

there is every indication that giants

really did walk the Earth in ancient times.

SHATNER: Could the human family tree

have once included a branch with actual giants?

Many experts believe it's possible,

not only because of the fossil evidence

but also because legends of extraordinarily large beings

have persisted for thousands of years.

In the European tradition, we have, uh, creatures

like giants that are very, very widespread.

We know now that folklore can last thousands of years.

So, could ancient people have encountered Denisovans

and interpreted them as giants,

as sort of brutish, as living differently from us,

but still able to, uh, interact with us?

Or maybe they dug up some bones or stumbled across them

and said, "Wow, these guys look really different than we do,"

and then came up with the stories.

I'm sure there are other archaic versions of humanity

out there that we have not yet discovered.

So I think we're just beginning to unravel the family tree.

There are other hidden branches out there

There are other hidden branches out there that have not yet been found

that have not yet been found

because we don't have evidence yet.

because we don't have evidence yet. But I think we will, as the years go by.

But I think we will, as the years go by.

Many experts now believe that early humans coexisted

with a number of different species that were similar to us.

But if that's true, then what happened to them?

Did they all just die out?

Or could some still exist in remote areas

Or could some still exist in remote areas all over the world?

all over the world?

SHATNER: 27-year-old Dean Harrison

is out for a late-night jog

in a wooded area near the town of Ormeau.

Suddenly, he sees a large creature moving in the forest.

(low grumble)

HARRISON: I got these chills

HARRISON: I got these chills that I could not explain that went

that I could not explain that went

from my head to my toes, and then back up again.

My hair went on end,

because I could hear it walking through the swamp.

Crunch, crunch, crunch.

Pulling up the foliage

Pulling up the foliage out of the ground and throwing it

out of the ground and throwing it

through the rest of the forest.

I moved my eyes to see this huge silhouette

standing there in the bush line right behind me.

We're talking about eight feet, roughly.

There was something about this that just,

alarm bells went off in my head, and I ran as fast as I could.

SHATNER: Although Dean's nighttime encounter

with the enormous creature was brief,

further research led him to believe

that he had encountered an elusive species

that is commonly referred to as the yowie.

LYLE BLACKBURN: The yowie is a hair-covered,

LYLE BLACKBURN: The yowie is a hair-covered, manlike creature that's said

manlike creature that's said

manlike creature that's said to live on the Australian mainland.

to live on the Australian mainland.

There's been thousands of sightings

of this creature over the years,

and stories of it even date back to Aboriginal legends.

HARRISON: The Aboriginals had a lot of names for this creature.

There was yahoo or yuree, yaree, youree,

depending on which dialect and-and which area

you came from that-- which, how you pronounce it.

The first sightings were written in the papers

in Australia since the 1800s.

Most people describe them like a big human.

The head sits on the shoulders and a little bit protruded.

Massive shoulders like cannonballs.

Very, very muscular. Deep, muscular chest.

Very long arms, compared to a human.

Uh, shorter legs.

Deep-set eyes and heavy eye ridges.

Uh, protruding jaw.

Quite a flat, splayed nose.

You can get them anywhere up to about nine,

even ten feet tall, some people say.

And there's no shortage of them

because the sightings are growing.

SHATNER: Dean's encounter inspired him to form a group

known as Australian Yowie Research, or AYR.

HARRISON: We have basically created a group

where people can turn to and look for the answers

once they have an encounter with one of these creatures.

On our expeditions, we've had a lot of sightings

and encounters over the course of the last 25 years

along the Great Dividing Range from the bottom end of Victoria

all the way to the top end of Australia.

SHATNER: Could a species of giant, ape-like humans

really be hiding throughout Australia?

It may sound far-fetched to some.

But the truth is that the numerous sightings

of the yowie aren't the only evidence

that a large cousin of man may still be living in the wild.

Because there are reports of similar creatures

all over the world.

The general idea of an undiscovered

large, ape-like creature living in the woods

is very common around the globe.

Whether we're talking about the Himalayas for the Yeti,

the U.S. for Bigfoot,

or whether we're talking about Australia and New Zealand

for the yowie,

this is something that appears to be a worldwide creature.

Evolutionary biologist Jane Goodall at one point said

it was possible that such a creature could exist.

And when you have someone with that sort

of a scientific reputation that will say

there is a possibility that this creature exists,

that's very compelling evidence.

BLACKBURN: If we look back at early man,

there's evidence of similar types of hominids.

If they developed in some shadowy place

and continued to survive and evolve,

these early humans could have become

what we know as Bigfoot, yowie or the Yeti.

And if we were to actually find undeniable photo

or video evidence of these creatures,

it would completely change the way we've thought

about everything, i-including our own evolution.

These creatures could be closely related to us.

This could be a branch of our own ancestral tree.

SHATNER: Is it possible that the yowie, Bigfoot and the Yeti are real,

as the countless sightings around the world suggest?

And if so, are these creatures part of a lost branch

of the human family tree?

Perhaps the answer can be found by examining a creature

that some believe left behind

that some believe left behind physical evidence of its existence

physical evidence of its existence

physical evidence of its existence high in the Himalayan mountains.

high in the Himalayan mountains.

From their Makalu base camp, located roughly 12 miles

From their Makalu base camp, located roughly 12 miles southeast of Mount Everest,

southeast of Mount Everest,

the mountain expedition team of the Indian Army

releases a photo of an unusually large set of footprints.

COLLINS: An expedition from the Indian Army

noticed very strange tracks in the snow.

And when they looked at them, they realized that each one

was 32 inches in length and 15 inches in width.

And they came to the conclusion

that they possibly belonged to the legendary Yeti.

And we know it in the West as the Abominable Snowman.

VIEIRA: The Indian Army

are not prone to throw out such sensationalistic material.

So that caught people, a lot of people, off guard.

And you look at these prints

and you start to ask the question,

and you start to ask the question, "How big a creature would create them?"

"How big a creature would create them?"

SHATNER: Curiously, this isn't the first time

that massive, bipedal footprints have been found

in the vicinity of Mount Everest.

In 1951, British mountaineer Eric Shipton captured a photo

of what appeared to be a giant footprint

with an ape-like thumb instead of a big toe.

BLACKBURN: One thing that supports the credibility

of all these sightings is that so many people

have described the same thing.

There has been numerous footprints

that have been cast and observed and photographed over the years.

And this just corroborates

the different witness sightings to suggest

that something is still out there.

The idea that massive creatures like the Yeti

are living in the wild might sound far-fetched to some,

but there have been many similar accounts

of strange, bipedal animals throughout history.

For instance, there's a particular species

that was believed to inhabit North America,

and would only come out at night.

SHATNER: Local farmer Felix Axley is planting

his first crops of the growing season

when he feels his plow catch on something beneath the soil.

He digs beneath the dirt

to find the source of the impediment

to find the source of the impediment and pulls out a strange carved statue

and pulls out a strange carved statue

of two creatures that appear to be human

but have short bodies and large, round heads.

but have short bodies and large, round heads. The face, they almost, uh, look flat,

The face, they almost, uh, look flat,

you know, and, uh,

and they showed their eyes as very prominent.

When Felix actually dug it up,

he probably didn't know what he was looking at,

so he put them on a sled and drug it

back up to his farmstead and leaned it against the well,

and it stayed there for years and years.

SHATNER: The odd statue remained a local curiosity

for more than a century, but today,

it is kept at the Cherokee County Historical Museum

because experts have determined that the carving depicts members

of a legendary civilization who the Cherokee referred to

as "the moon-eyed people."

VIEIRA: In 1797,

Benjamin Smith Barton came out with a book

and he cited a Revolutionary War veteran

who was an interface between the government

and the Cherokee people in Georgia, who told him

about the legend of the moon-eyed people.

The legend is that they were people with huge eyes

who could see at night and not so well during the day.

The Cherokee of the Appalachia of North America

entered this region around 1,000 years ago.

And when they got there, it was already occupied

by a type of population

they refer to as the moon-eyed people.

And it was said that they had existed

for many tens of thousands of years.

JOHN STAMEY: The moon-eyed people have been described

as being about three, three and a half feet tall,

and having larger heads proportionally than we do.

They've also got pale blue eyes and pale skin.

Which also means that direct sunlight is not good for them,

so they are primarily nocturnal.

BILLY PALMER: The moon-eyed people

lived on the eastern bank of the Valley River.

And then the Cherokees,

they lived between the Hiwassee and Valley River.

The Cherokees lived with the moon-eyed people

The Cherokees lived with the moon-eyed people in harmony for a while,

in harmony for a while,

but then they eventually

got in arguments for property reasons.

And so, the moon-eyed people

were displaced by the Cherokees.

SHATNER: According to legend,

after being driven westward by the Cherokee,

the moon-eyed people disappeared...

...and were never seen again.

Was there actually a primitive society of pale,

human-like beings with enormous eyes

that lived in North America?

Many experts believe it's possible,

because the Cherokee aren't the only Native Americans

whose legends speak of the moon-eyed people.

VIEIRA: What's interesting is that Lakota, Sioux,

so many tribes have legends of short people with huge eyes.

It's been said that even Lewis and Clark

met with Native tribes in South Dakota,

and were told by the Native people there

that these little people were malevolent

and had poison arrows and actually killed

some of their members.

And we're talking about fierce warriors,

not people prone to superstition.

THOMPSON: One of the very interesting aspects

is trying to overlay these sort of characters

with what we now have coming from archeology.

For example, we know that there were a lot of hominids

running around the Earth.

It's not out of the realm of possibility

that some of these stories we have

refer to long-held folklore notions

of when the world was a much more diverse place.

SHATNER: Could there have been entire civilizations

belonging to other branches of the human family tree

that disappeared from history?

It's a fascinating notion.

But in the case of the moon-eyed people,

many researchers believe that actual physical evidence

of their society still exists.

Standing atop the peak of this worn mountain

at the southern end of the Appalachians

is a jagged rock wall

is a jagged rock wall that is 855 feet long.

that is 855 feet long.

that is 855 feet long. COLLINS: The moon-eyed people,

COLLINS: The moon-eyed people,

they are accredited with the creation

of incredible structures on the side of mountains and hills

like on Fort Mountain.

In fact, there's even a sign on Fort Mountain

saying that these structures were created

by the moon-eyed people.

STAMEY: We're pretty certain

it was not built by the Cherokees,

because the Cherokee did not use rock

in their construction, they used a concoction

in their construction, they used a concoction called wattle and daub...

called wattle and daub...

...and that was straw, clay and mud.

Since it's not built by the Cherokees,

it might very well have been built by the moon-eyed people.

It might seem unbelievable that there was a race

of pale humanoids with enormous, moon-shaped eyes

that once inhabited North America,

that once inhabited North America, but there have been reports

but there have been reports

of an even more incredible creature

that dwells in the swamps of South Carolina.

A bizarre beast that is said to be part man...

...and part reptile.

SHATNER:: 17-year-old Christopher Davis

stops to change a flat tire

deep in the back roads of Scape Ore Swamp.

And he quickly senses that he is not alone.

About the time he's putting the jack and the flat tire

into the trunk of his car,

he looks up and he sees

something coming at him in the moonlight.

The closer this thing got,

the more he knew this wasn't a person.

He looked up and he saw a greenish-looking figure,

maybe about seven to eight foot tall,

and arms that draped down to the side

with three claws on each hand.

SHATNER: Sensing he could be in danger,

SHATNER: Sensing he could be in danger, Christopher bolts into the car

Christopher bolts into the car

Christopher bolts into the car and drives away as fast as he can.

and drives away as fast as he can.

and drives away as fast as he can. (engine starts)

(engine starts)

BLACKBURN: Christopher looked

in his rearview mirror

in his rearview mirror and could see this thing pursuing him.

and could see this thing pursuing him.

He was completely frightened, utterly overwhelmed

He was completely frightened, utterly overwhelmed by what he saw coming at him.

by what he saw coming at him.

Eventually, it disappeared into the darkness.

SHATNER: Christopher got home safe and sound.

But his terrifying story quickly spread through the media.

Newspapers and television stations

jumped on the bizarre encounter.

ANCHOR: Deep in the Scape Ore Swamp of South Carolina,

there reportedly lives a creature

that is part man and part beast.

A creature that 17-year-old Christopher Davis claims

attacked his car late one night on this lonely country road.

Seven feet tall.

Long arms, red eyes.

STAMEY: There was a media frenzy once the story got out.

There were stories in newspapers in Korea

There were stories in newspapers in Korea about the Lizard Man.

about the Lizard Man.

And that's just a tribute to the viralness

And that's just a tribute to the viralness of the Lizard Man.

of the Lizard Man.

SHATNER: During the media frenzy,

dozens of other eyewitnesses began contacting

the Lee County Sheriff's Office.

They all claimed to have had similar encounters

with a strange, three-fingered creature

that appeared to be part man and part reptile.

But rather than dismiss such reports,

law enforcement took them quite seriously.

They had the witnesses come in, they interviewed them--

in some cases, gave them polygraph tests.

And all of the witnesses that reported sightings

of the Lizard Man were credible.

Could there really be a reptile species

that evolved to walk upright like humans?

It may sound far-fetched,

but many researchers believe it's possible.

And as evidence,

they point to a creature in the Bible

that exhibited characteristics of both man and reptile.

FISHER: The serpent in the Garden of Eden

is not like normal serpents in that it can speak.

The Hebrew Bible describes how the serpent tricked Eve,

and as part of the punishment,

he is cursed and told that it's going to go on its belly

in the dust, which implies it had some prior, uh,

mode of locomotion that was different.

So, it may have been a walking serpent.

Some legends that develop--

you see this in some medieval artwork--

the serpent was understood to have had legs.

Some of the Jewish legends about Eve and the serpent

imply that it may have also had some kind of arms or hands

that could, uh, push her to touch the tree,

or bringing fruit to her.

So the idea of this serpent-human hybrid

So the idea of this serpent-human hybrid is a very ancient one.

is a very ancient one.

SHATNER: The notion that an ancient species

of reptiles with human characteristics

may have evolved alongside people is intriguing.

But could there be scientific evidence

But could there be scientific evidence to suggest that such beings exist?

to suggest that such beings exist?

Neuroscientists at the Max Planck Institute

publish a landmark study.

They claim to have discovered an evolutionary link

between the development of the human brain

and early reptiles that lived in the distant past.

We know that humans are mammals, and reptiles are reptiles.

But at a certain point, we had a common ancestor:

cynodonts, which lived 235 million years ago.

cynodonts, which lived 235 million years ago. They're these small-bodied creatures

They're these small-bodied creatures

that had rodent-like attributes,

even though they were still reptiles.

KIRSTEN FISHER: In evolutionary terms,

we share, uh, many features with our reptile relatives.

Things like the amniotic sac,

four limbs, elements of our neurological system,

like the basal part of the brain. Also, our cerebellum.

So we can look at any familiar reptile,

whether it's a crocodile or a turtle

and know that it is, in fact, your relative,

and know that it is, in fact, your relative, albeit a very distant relative.

albeit a very distant relative.

SHATNER: Could it be that many of the evolutionary traits

found in modern humans didn't arise from ancient primates

but rather from a reptilian ancestor millions of years ago?

And if so, is it possible that there are bizarre

human and reptile hybrids that are still alive today?

STAMEY: There have been a number of other sightings

of the Lizard Man outside of Lee County

and Sumter County in South Carolina.

There's some in Europe, there's some in South Africa.

Every one of them was about six to eight feet tall

with red eyes.

It always had red eyes.

That is one commonality that you can't get over.

And so, it is certainly possible that the Lizard Man is real.

If it was ever proven that a race of reptilians

If it was ever proven that a race of reptilians existed on Earth...

existed on Earth...

well, that would challenge everything

well, that would challenge everything we currently think about evolution.

we currently think about evolution.

Which could also be the case with some ancient skeletons

that were recently found in Africa.

Skeletons that are shedding new light

on the origins of mankind.

SHATNER: The Bloubank River valley, South Africa.

September 13, 2013.

Two amateur spelunkers enter the Rising Star Cave system

and explore its twisting depths.

Inside, they make an unexpected discovery.

Inside, they make an unexpected discovery. The cave is littered...

The cave is littered...

with the bones of 15 people.

Carbon dating reveals the bones

Carbon dating reveals the bones are more than 300,000 years old.

are more than 300,000 years old.

But even more astonishing, scientists determine the bones

belong to a previously unknown species of hominid.

They name it Homo naledi.

So, what's really remarkable about this discovery

of Homo naledi was its very small cranial capacity.

Homo naledi has a cranial capacity around

610 cubic centimeters, and anatomically modern humans

have roughly 1,270 cubic centimeters.

So, we're seeing a huge difference

between these two species living at the same exact time.

And that says a lot about human evolution,

that it's not necessarily having a giant brain

that's gonna get you far in life.

TOCHERI: The discovery of Homo naledi opened up a lot of questions

about how we thought about the evolution

about how we thought about the evolution of our species in Africa,

of our species in Africa,

where we find another species of human overlapping with us,

that shares some aspects of their anatomy with us,

but other aspects look very, very different,

showing another direction that evolution took

showing another direction that evolution took in their particular lineage.

in their particular lineage.

SHATNER: Ever since Charles Darwin published

The Origin of Species,

we've assumed that evolution favors species

that have the most desirable traits, such as intelligence.

But some researchers believe the discovery

of Homo naledi's smaller brain size

raises the possibility that survival of the fittest

may not always be the case.

REAGAN: Fittest doesn't necessarily mean

you can run a marathon, you can scale tall buildings.

It doesn't even mean you can do calculus or win a Nobel Prize.

It's whoever can survive and hack it in their environment.

SHATNER: If it's true that being the strongest, the fastest

or the smartest isn't required

to ensure the survival of a species,

could our quest to unravel mankind's origins

have been misguided all this time?

And if so, is it possible that we'll ever truly

be able to answer who we are and where we come from?

FINLAYSON: It's clear that our story is being rewritten all the time.

FINLAYSON: It's clear that our story is being rewritten all the time. We know the basics, and we know that

We know the basics, and we know that

we're part of an evolving lineage,

but I'm sure more will be found

in terms of fossils but also in terms of the DNA,

in terms of fossils but also in terms of the DNA, which has given us a lot of information

which has given us a lot of information

about makes us human.

TOCHERI: Human diversity was just so much greater

in the recent past than it is today.

Over the past hundred years, we've gone from having a handful

of species, you know, separated by vast periods of time

to a very bushy, bushy tree, family tree

full of different examples of how to be human

at different points in time over the past six million years.

It's incredible.

REAGAN: We talk about this missing link,

but we're discovering more and more species

that fit outside of what we had expected.

So it's making us rethink the way humans evolved.

And I think we're gonna continue seeing these discoveries,

to hopefully find more pieces of this puzzle that will

help us understand where we came from.

And hopefully better inform us how to keep moving forward.

Will we ever find the elusive missing link

that explains mankind's origins?

Each skull or skeleton that we uncover certainly brings us

one step closer to finding the answer.

But then again, perhaps we shouldn't assume

that the purpose of evolution is all about us.

Maybe human beings are just one piece

of a much larger mystery that, at least for the time being,

remains unexplained.

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