Original subtitles

[narrator] Archaeologists make a remarkable discovery

in Egypt's Valley of the Kings.

They discovered the burial chamber,

to an undiscovered tomb.

But instead of finding the remains of a burial,

the tomb was mostly empty.

Is it possible that this mysterious,

empty burial ground

was once the final resting place

of a female member of the Egyptian royal family?

Extraordinary structures are revealed

in the Jordanian desert.

[Anthea] The sheer scale of them shows

that they were clearly important.

But what were they for?

On the outside of an Israeli town,

excavations unearth a strange complex.

[Teddy] At first glance,

it looks like just a low, crumbling wall

sticking out of the sand.

But after some digging around,

they discover that it's actually part of a bigger complex.

[Dr. Amma] All told, the complex covers roughly 10,000 square feet.

So what was this place?

Ancient lost cities,

forgotten treasures,

mysterious structures.

As new technology uncovers remarkable tales,

hidden beneath the deserts of the world,

The "Secrets in the sand" will finally be revealed.

Spreading over 160 square miles of the Egyptian desert,

just east of the Nile River,

the city of Luxor is one of the hottest and driest

urban centers in the world.

[Dr. Alison] Summer temperatures

frequently hit 104 degrees Fahrenheit,

and its low annual precipitation

is on par with the driest sections of the Sahara.

[Dr. Anthony] Luxor has a special place in history

as the former city of Thebes,

the religious capital of ancient Egypt.

It's famous for its ruins of 4,000-year-old temples,

palaces, and monuments.

Some of those are still standing today,

making the city one of the largest open-air museums

in the world.

But the most renowned landmarks

are the series of tombs, west of the Nile

in an area called the Valley of the Kings.

[Dr. Dan] The Valley of the Kings was the chosen necropolis

for most of Egypt's New Kingdom rulers and pharaohs.

The Valley of the Kings is a small valley

surrounded by these steep limestone cliffs,

that is a topography that is perfect

for carving individual tombs into the hillside.

And of the 62 tombs that have been found so far,

the most famous

is that of the Boy King, Tutankhamun,

discovered with most of its artifacts intact in 1922.

A team of archaeologists

is working near the western edge of the Valley,

about a mile from where most of the rulers' tombs lay,

when they come across a surprising discovery.

They found an entrance to a 32-foot passageway,

which was almost entirely filled with debris,

so it took a long time to clear.

When they finally got through,

they discovered the burial chamber

to an undiscovered tomb.

But instead of finding the remains of a burial,

the tomb was mostly empty.

[Dr. Alison] There were fragments of clay vessels

scattered on the chamber floor.

One of the pottery pieces bore a label indicating

it had contained the substance "natron,"

which was commonly used for embalming.

So that confirmed a burial did take place,

at least initially.

[Dr. Anthony] The tomb was discovered in an area

mostly reserved for the wives,

mothers, and daughters of the pharaohs,

the Valley of the Queens.

So it was suggested that it belonged to a woman.

After all, the closest tombs in the vicinity

belonged to the wives of King Thutmose III.

Is it possible that this mysterious,

empty burial ground

was once the final resting place

of a female member of the Egyptian royal family?

A detailed survey

and investigation of the inner tomb

leads to some critical clues.

In addition to the broken shards of pottery,

there were fragments of tiling

that had fallen from the ceiling.

After piecing them together, like an ancient jigsaw puzzle,

a pattern emerged.

It was a painted blue night sky

decorated with yellow stars,

a design traditionally associated with the pharaoh.

[Dr. Dan] More significantly,

the walls were decorated

with hieroglyphic scenes from the Amduat.

That's this sacred funerary text

that describes the sun god, Ra,

as it makes this nightly journey

through the 12 regions of the underworld.

It symbolizes death and rebirth.

And as with the painted night sky,

the Amduat was typically reserved

for Egyptian rulers only.

Putting two and two together,

this undiscovered tomb

was in a section of the necropolis

populated mostly by women.

And yet it bore the distinct hallmarks

of a pharaoh's funeral rites.

So is it possible that this is the secret tomb

of a female pharaoh?

Most of Egypt's rulers were men.

One of the few exceptions was Queen Hatshepsut.

Hatshepsut was the eldest daughter

of the 18th dynasty king, Thutmose I.

She was married to her half-brother,

Thutmose II,

who inherited the throne around 1500 BCE.

Now, when Thutmose II died 13 years later,

the throne normally would've just gone

straight on to his son, Thutmose III,

but Thutmose III was still an infant,

so his wife and half-sister, Hatshepsut,

acted as regent for the young king.

[Dr. Amma] By most accounts,

her reign was a successful and peaceful one.

She defended Egypt's borders

and her foreign policy was based on trade, not war.

Seven years into her reign,

Hatshepsut was given a full royal title,

essentially making her a female king.

Interestingly, it was at this point

that she stopped being depicted as a female.

In paintings and sculptures,

she began to appear wearing male clothes and regalia,

including a beard.

Scholars believe this wasn't an attempt

on anyone's part to pass her off as a man,

but rather to indicate

she deserved the respect of a king.

The continued examination

and analysis of the tomb's walls and floor

results in a breakthrough.

[Dr. Dan] There were small pictures of a broken alabaster jar

that probably once contained ointment.

Now, the same jigsaw puzzle approach

was used to piece this jar together,

but this time, it revealed a name.

King Thutmose II.

The assembled jar also included his wife,

Queen Hatshepsut's name.

And the full inscription clearly indicates

Hatshepsut buried her husband right here.

[Dr. Amma] This was an incredible turn of events.

First discovery of a royal tomb

in the Theban necropolis in 100 years.

The implications were enormous.

Egypt was at the peak of its power in the New Kingdom

as it continued to amass great wealth

along with its growing empire.

Plus, this discovery presented an opportunity

to study a pharaoh

about whom very little was known.

[Dr. Alison] Thutmose II was an 18th dynasty pharaoh

who came to power in the second millennium BCE.

Some historical records state that during his reign,

he squashed a rebellious uprising in Nubia,

what is now northern Sudan.

There was also an indication that he may have campaigned

with his armies to the eastern Mediterranean,

as far as Syria.

[Dr. Anthony] But Thutmose II was best known

for being the king who married

the future female pharaoh of Egypt.

So was Queen Hatshepsut

truly instrumental in selecting her husband's tomb

as the inscription suggests?

If that's the case,

why did she select an area over a mile away

from the traditional burial ground?

The Valley of the Kings was the main burial ground

of the Theban necropolis for New Kingdom pharaohs

for just under 500 years.

According to tradition, the pharaohs,

including future pharaohs in line for the throne,

planned their own funerary rites,

sometimes while they were still children.

This included choosing the location

and overseeing

the full construction of the tomb.

[Dr. Amma] So Hatshepsut may have overseen the actual burial,

but it was likely Thutmose

who had the tomb constructed here.

It also appeared

that Hatshepsut had planned to be buried close by,

since an uncompleted tomb just over 1,500 feet away

was discovered with inscriptions

stating it was intended for her.

[Dr. Alison] But in another twist to the story,

when Hatshepsut eventually did pass away,

20 years after Thutmose's death,

she was interred in the Valley of the Kings,

along with the other male pharaohs.

This was likely because she had acquired

the official title and status of king.

There were likely several factors

that played a role in Thutmose's unusual tomb location,

and we may never know all of them.

But one thing was noticeable.

Unlike King Tut's tomb,

which was discovered overflowing with trinkets,

jewels, and other grave goods,

Thutmose's tomb was empty.

So you have to wonder,

was it looted by grave robbers?

Tomb raiders were a persistent problem

in New Kingdom Egypt,

and their precious stolen goods

were a normal part of the local economy.

In some cases, they were professionals,

organized gangs who knew the tomb's layout,

how to access them,

and how to sell them on the black market.

In other cases,

it was it was the families of the deceased

who stole from their tombs.

The problem was so widespread

that officials took a range of steps to prevent it,

such as carving curses on doors

to scare would-be looters away.

But it seldom worked,

and the tomb raiders were frequently brazen

and highly destructive,

smashing sarcophagi

and tearing through the mummies' wrapped textiles

to access jewels and amulets.

After a thorough assessment of the tomb,

the possibility of a raid was ruled out.

There's no evidence of looting,

no signs of forced entry,

so if the grave goods aren't there

and they weren't stolen,

they must have been moved to a different location.

So the question is, why?

A closer look at the history

of ancient Egypt's funerary practices

reveals a possible answer.

[Dr. Amma] During the Old Kingdom,

from approximately 2700 to 2200 BC,

the Pharaoh's preoccupation with death and the afterlife

led to the creation of the Great Pyramids.

The more valuable artifacts

and offerings within the tomb,

the better prepared for the afterlife.

[Dr. Alison] But this came at a cost.

The mere sight of a pyramid

essentially announced the location and the opportunity

for tomb raiders to plunder.

Eventually, officials were unable to protect the mummies

of the Old Kingdom rulers.

This, in part, is what led New Kingdom rulers

to opt for concealment and secrecy

by digging hidden tombs deep in the hills

of the Theban necropolis.

[Dr. Anthony] Despite the authorities' best efforts

to keep the new location of the tombs a secret,

looters eventually caught on.

Officials were bribed,

and many of the workers who built the graves

got conscripted by gangs to help them.

In response,

New Kingdom priests and royalty

began to secretly remove the mummies

from the underground tombs

and take them to a second,

even more hidden location,

referred to as the Royal Cache.

But the Royal Cache was intended

as a temporary hiding place for the mummies.

This wasn't an attempt

to reconstruct entirely new tombs

for each of the pharaohs.

In the case of Thutmose II,

it's hypothesized that an undiscovered second tomb,

likely does exist somewhere,

and that all those missing valuable grave goods

are probably just sitting somewhere,

waiting to be uncovered.

An extended search of the surrounding area

leads to a curious discovery.

An enormous man-made mound was discovered

not far from the original empty tomb,

made up of piles of limestone rubble

reaching 75 feet in height.

[Dr. Alison] It appeared that the mound was deliberately constructed

to conceal something underneath.

Could it be the opening

to Thutmose's second tomb location?

The excavation of the limestone mound

is still pending.

In the meantime,

the discovery of Thutmose II's original tomb

represents a crucial missing piece

in the history of Egypt's 18th dynasty.

And while it helps solve one enduring mystery

about the ancient pharaoh,

it continues to pose new questions

about his fate and his legacy.

The basalt flats of the Arabian Peninsula

extend tens of thousands of miles

across the borders of Jordan, Syria,

and Saudi Arabia.

[Dr. Anthony] These basalt fields are known as harrats,

which comes from the Arabic for "stony area"

or "lava field."

They formed millions of years ago,

when the Arabian plate began to shift away

from the African plate,

along the Red Sea Rift.

This gradual movement thinned the Earth's crust

and allowed magma to rise from the Earth's mantle

to the surface.

An archaeologist conducting aerial surveys

above the sprawling lava deserts of Jordan

spots something strange.

[Dr. Anthony] He began to notice enormous structures,

stretching across the harrats.

They were relatively uniform in shape

and clearly man-made.

But what stood out the most was their size.

[Dr. Amma] The structures are essentially huge rectangles

formed of two thick bands,

connected by much longer,

thinner rows of rock.

Today, we know these structures

as mustatils, or gates,

because of their unique shape.

[Teddy] Early surveys of the harrats

showed that the gates were often clustered

in groups of two or three,

but the total number remained a bit of a mystery

until Google Earth changed everything.

With mainstream satellite images available to the public,

archaeologists around the world

could explore the desert from their own homes.

So far, more than a thousand of these gates have been found.

We can't be sure,

but we believe they were built by nomadic tribes

thousands of years ago,

the ancestors of the modern-day Bedouin people.

The sheer scale of them shows

that they were clearly important.

But what were they for?

These extraordinary gates

aren't the only monumental sculptures

on the Arabian Peninsula.

South of the Jordanian basalt flats

lies the Harrat Khaybar,

one of Saudi Arabia's largest lava fields.

Among the volcanic cones,

vast stone shapes known as kites,

have been sculpted into the landscape.

Over 900 of these kites

have been have been spotted in Harrat Khaybar alone.

These structures are even larger than the gates,

with some measuring over a quarter of a mile long.

Many of these structures date back,

roughly to the Holocene humid period,

which spanned roughly 9000 to 5500 BCE.

Back then, the desert belt of North Africa and Arabia

was far greener and more fertile,

an ideal hunting ground for people living in the area.

And these structures weren't just random formations.

They were built with a clear and deliberate purpose.

These kites have been referred to as megatraps,

and that's exactly what they were.

It's believed the ancient nomads

used the kites' long walls or strings

to drive herds of prey toward the head,

where they would become trapped.

[Anthea] The traps would have taken weeks

or even months to build

and would have required a huge amount of manpower.

Just like the gates,

they demonstrate an advanced early engineering,

which makes us wonder

whether they served a similar function.

Could the gates farther north

have also served as huge hunting traps?

When archaeologists on the ground

get a closer look at the desert gates,

they see just how intricate these structures are,

and they discover a hidden feature.

Taking a closer look at the mustatils,

we can get a sense of how much care was taken

in their construction.

Each of the gates' long bars

is made of two parallel lines

of specially chosen flat stones

placed on their edges facing each other.

The space between these larger rocks

was then filled in with rubble.

At the top of the mustatils, we find the head,

a platform filled with rocks

that once stood several feet high

and formed the thickest band in the structure.

At the very center of the heads of most gates

lies a hidden chamber.

These chambers are relatively small,

typically 10 to 30 feet wide.

While excavating the walls of one mustatil,

a team of archaeologists makes a shocking discovery.

While excavating the walls of one mustatil,

a team of archaeologists makes a shocking discovery.

They began to uncover human bone fragments.

The bones belong to nine separate individuals,

two infants, one child,

a teenager, and five adults.

So could these structures

be something other than animal traps?

Could they actually be elaborate funerary monuments?

The search for answers leads to another nearby site,

where ancient roadways in Northwest Arabia

are flanked by mysterious stone sculptures.

[Anthea] These aren't gates or kites, but keyholes.

As the name suggests,

they're made up of two main components,

a circular section at one end placed at the point

of an elongated triangle.

Nearly 18,000 of these keyholes have been found

over roughly 100,000 square miles of the Arabian desert.

[Dr. Amma] Like the gates,

the keyholes are often grouped in elaborate formations

leading away from a central corridor.

It's believed that they may have been used

to shepherd animals into specific pastures.

But they also serve another more symbolic function.

Inside the circular ends of these structures,

we find piles of stones called cairns.

These aren't decorative.

They actually mark tombs.

Looking at them from above,

you can see that the tombs have been deliberately organized

with a central roadway,

running through them

near the widest point of the triangle.

Today, we now know these arrangements

as funerary avenues.

It could be that people wanted to bury their loved ones

on frequently traveled routes

so that their memory would be kept alive

by people passing by.

Could the monumental gates in Jordan

have served a similar function?

Excavations of ancient gates in Saudi Arabia

unearthed yet more skeletal remains.

But these bones point to a different possibility.

It turns out that many of these mustatils

contain thousands of bone fragments.

But the vast majority of these bones

aren't actually human.

They're animal bones.

There's evidence that some of these animals

were wild, like gazelles,

but most appear to have been domesticated.

[Dr. Amma] Radiocarbon dating shows us

that they're up to 7,000 years old,

which makes these stone monuments

about 2,000 years older

than both Stonehenge

or the earliest Egyptian pyramids.

[Teddy] Cattle herding would have played a central role

in the lives of ancient people

living in the region at the time,

providing a vital source of food.

But why were they buried here?

Why go to the trouble

of building such an elaborate burial ground

for animals?

As work on the mustatils continues,

researchers working a site at Yemen's Wada'ah sub-district

within the Sana'a government,

come across another remarkable cattle burial.

We found a ring of more than 40 cattle skulls

that had been planted nose-down in the earth.

At the center of the ring, there was one more skull,

also buried facing downwards.

This deliberate arrangement suggests

the skulls represented some kind of ritual

or symbolic significance.

The cattle remains were found near a stone platform

and surrounded by several hearths.

The skulls and hearths combined

paint a vivid picture of some kind of ritual feast,

one that seemingly involved

the sacrifice of domestic animals.

The discovery of ritual cattle sacrifice in Yemen

leads to a revelation for experts

working on Arabia's colossal stone gates.

We now believe that these huge stone gates

were built to host similar rituals.

Each of the gates has a narrow entrance built into its base.

These are typically less than three feet wide,

which may have been to encourage people

to enter the structure in single file.

[Dr. Amma] We can't be sure,

but the large courtyards inside the gate

could have accommodated lots of people,

perhaps an audience for the animal sacrifices.

It's thought that these mustatils

are some of the oldest monuments built

by these Neolithic cattle cults.

They've been found over an area

of just under 80,000 square miles,

which tells us that their beliefs and rituals

were extremely widespread during the late Stone Age.

Over time, the ritual significance of these sites

appears to have changed with animal sacrifices

slowly giving way to human burials.

There isn't any evidence to suggest

that the humans buried here were sacrificed themselves.

Instead, the continued use of these monuments as graveyards

only emphasizes how important these spiritual landmarks were

to the people who built them.

Today, work continues to excavate and date

even more of these enigmatic gates to chart the lives

of the ancient Arabian cattle cults.

But who or what these cults worshiped

remains an enduring mystery.

Around 35 miles southwest of Jerusalem,

in Israel's Negev desert,

lies the Bedouin town of Rahat.

With a population of just over 75,000,

it's the largest of the Bedouin cities,

but roughly 60% of the people who live there

are under the age of 18,

so its nickname is the City of Children.

[Dr. Alison] It's on the edge of a desert,

so it has a hot, semi-arid climate

and sees only about ten inches of rain each year.

The city is surrounded by small rolling hills

made up of loess, a fine material comprised

mostly of silt and dust distributed by the wind.

On the southern outskirts of town,

a team of archaeologists is carrying out excavations

in advance of a future construction project

when they unearth something surprising.

[Teddy] At first glance, it looks like just a low, crumbling wall

sticking out of the sand.

But after some digging around,

they discover that it's actually part of a bigger complex.

[Dr. Amma] It consists of several rooms

of varying sizes joined together,

some rectangular, others more square.

And they're all separated by walls

made up of stones cemented together.

All told, the complex covers roughly 10,000 square feet,

a large area,

and looks to be very old.

So what was this place?

Another stone structure was discovered

not too far from the complex of Rahat.

Researchers determined it to be

one of the oldest rural mosques ever found.

It's mostly just one small square room,

around 65 square feet,

but one of the walls isn't a straight line.

It has a half-circle jutting out

of the middle of it facing south,

the direction of Mecca,

the holy city of Islam.

The half-circle is a prayer niche called a mihrab.

[Dr. Dan] Using pottery and coins discovered at the site,

researchers figured this dates to the late 7th century

or early 8th century CE.

Now, it's known that Islam did originate

about 100 years before that in what is now Saudi Arabia,

but it didn't become the dominant religion

in this region for at least 200 years.

So finding a mosque this old is rare.

Given the mosque's proximity to the complex

and the similarities in construction style,

I think it's safe to assume that the complex

was from around the same period,

around 1,200 years ago.

But what was it?

As the team explores the complex further,

something strange happens.

When they knock on some of the stones,

they hear an echo emanating from beneath the ground.

They're able to create a small hole

to lower a camera down

and are shocked at what they see.

There's an incredible underground complex of vaults.

They're built out of limestone blocks

about 18 feet under the ground

and measuring roughly eight feet tall.

The compartments are linked by tunnels

and have arched ceilings,

also constructed out of stone.

These vaults were probably used as storage areas,

but for what?

The area around Rahat

was once an ancient farming community.

There's evidence to suggest

that the Negev had large-scale agriculture

between the 4th and 11th century CE.

[Dr. Dan] This was no easy task,

considering the environmental factors.

I mean, there was always the threat of a drought,

and a drought could last for several years,

but the people who lived here

had extremely clever ways of managing water.

[Dr. Alison] They used a damming technique,

building stone terraces into hillside plots of farmland,

and also had a system of channels

for collecting runoff from slopes.

Using these methods, they were able to grow

various legumes and grains, including wheat and barley.

So maybe the structure discovered at Rahat

was used for storing food supplies,

or even a produce marketplace of some kind.

Further investigation of the site

reveals architectural details

that may just support this theory.

The western area has a series of big rooms,

and the eastern side contains a large open hall.

These spaces would be ideal for conducting commerce

or further storage beyond the underground vaults.

[Dr. Amma] But if the complex was for storing food products

or used as a marketplace,

there would probably be evidence left behind.

But all they found in the vaults

were some clay shards from oil lamps.

So I think it's unlikely

that the structure was used for that purpose.

It must have been for something else.

[Dr. Alison] Given its size and location on the outskirts of the city,

maybe the building had a military function

for protecting Rahat from invading armies.

The vaults could have been for storing weapons

or a system of defense.

In central Turkey's historic Cappadocia region

is Derinkuyu,

an ancient city with extensive underground complexes

that some believe were vital to its defense.

During the Byzantine period,

Christians were under constant threat of attack

from the Romans.

And it's thought that these tunnels

were built to hide the people of the city from persecution.

[Dr. Amma] Some of the tunnels are not very big,

which might appear to be a design flaw.

But it was likely done on purpose

so that if attackers tried to enter,

they would have to be in a single row

and hunched over, making it easier

for defending soldiers to kill them.

Maybe the underground system at Rahat

served a similar purpose.

[Teddy] But there's no historical documentation

to indicate that this was an important town

that needed defending back then.

It was a simple, rural, agricultural community.

And there's also no archaeological evidence

of conflict.

No military artifacts were discovered.

As the team continues to investigate the site,

they find certain items

that may just provide some answers.

As the team continues

to investigate the site around Rahat,

they find certain items

that may just provide some answers.

[Dr. Alison] They came across two ovens.

Now, that might not sound like a big deal

because people had to cook, right?

But these ovens are way bigger than conventional ones.

Too big to be just for preparing regular family meals.

And right next to one of them is a water cistern.

Olive pits were also found at the site.

All of this adds up to one thing.

On top of being a residence,

this complex was probably used

to manufacture soap.

The ovens were likely used

to cook up a mixture of ingredients.

They would have needed olive oil,

which explains all the olive pits,

and they would have needed water.

And lo and behold,

one of the ovens is right next to a cistern.

[Dr. Amma] This was the perfect location for soap-making,

with all the necessary ingredients found

in the surrounding region.

Old soap recipes require saltwort plants,

which are indigenous to the Negev desert,

and olives were extensively available

in the nearby South Hebron Hills.

Soap-making in the ancient world

goes back much farther than the early Islamic period.

Soap first being used for personal hygiene

dates back to the ancient Egyptians,

around 1550 BCE.

They created a soap-like substance

by combining animal and vegetable oils

with alkaline salts

for both cleaning their bodies

and treating skin conditions.

As Islam spread to become the primary religion

in the Middle East,

an emphasis on hygiene and cleanliness emerged.

Islam is a very ritualistic religion,

and certain hygiene-related customs

are expected to be followed.

Muslims are encouraged to perform ablution,

known as Wudu,

before prayers,

which involves washing the face,

hands, arms, feet,

and rinsing the mouth and nose.

[Dr. Alison] Good grooming and the use of perfumes,

Tayyib, are also expected.

A devout Muslim should show loyalty to God

and respect for his fellow Muslims by smelling good,

particularly at group prayer.

The cleanliness of clothing, living spaces,

and the body are a high priority.

Researchers believe that the complex at Rahat

may be the oldest soap-making facility

ever discovered in Israel.

At the time, family recipes were heavily guarded secrets,

handed down from generation to generation.

And as Islam grew in popularity,

the demand for soap grew with it

and made some people extremely wealthy,

including whoever lived

in this once magnificent complex.

Tucked into the northern reaches of Egypt's

lies the Faiyum Basin,

a vast limestone depression

spanning more than 6,000 square miles.

The Faiyum Basin is incredibly unique,

because it's home to an oasis.

For thousands of years,

humans have been diverting water

from the nearby Nile River

into the basin to irrigate the land.

These irrigation systems supported large towns

during the ancient Egyptian Middle Kingdom

and the Roman period.

There are dozens of well-preserved Egyptian,

Greek, Roman, and Coptic Christian sites

dotted around the oasis,

making it an archaeological treasure trove.

As extraordinary as these ancient settlements are,

the oldest remains in the basin

predate humans by millions of years.

One of the best examples is Wadi Al-Hitan,

or Whale Valley,

a stretch of land, roughly 100 miles from Cairo,

where archaeologists have found fossils

dating back more than 40 million years

to the earliest aquatic whales

in the final stages of losing their hind legs.

For years, archaeologists have carefully cataloged

the marine mammals of the Faiyum depression.

But during a dig in the arid desert,

one team spots an entirely different set of remains.

[Anthea] They had been digging for several days

when they spotted a set of huge teeth

sticking out of the desert floor.

They quickly realized the teeth were attached

to a nearly perfectly preserved skull.

[Dr. Dan] It's some kind of mammal,

and this thing is clearly a predator.

It's got these teeth that are sharp

and look like they're perfect for slicing into prey.

Plus, it's got these big crests on the skull

that suggest it had really powerful jaws.

Based on the skull's size,

we can estimate this animal

was about the size of a modern-day leopard.

So what was it,

and how long ago did it roam the Faiyum Basin?

The discovery of the predator's skull

prompted comparisons to a set of remains

unearthed in the region 120 years earlier.

These fossils belong to a creature

known as Sekhmetops.

Sekhmetops was a formidable predator,

roughly the size of a modern-day lion

with a large, heavy head.

It shares many qualities with the newly discovered skull,

including its razor-sharp teeth,

specially adapted to bring down large prey.

So could the creature found in the Faiyum Basin

be from the same species as Sekhmetops?

Searching for answers,

the team performs a detailed analysis of the skull

in the hopes of establishing its age.

And the results are rather surprising.

The skull is around 30 million years old.

This means that this creature is from the Oligocene period,

which spanned from approximately 34 to 23 million years ago,

the same timeframe as Sekhmetops.

So it's entirely possible

that the two animals are closely related.

[Anthea] While it might be tempting to think Sekhmetops

and the newly discovered animal belong to the same species,

there are differences between them.

Besides being smaller than Sekhmetops,

the skull has distinctly feline features

with a shorter cat-like snout.

The differences between the remains

tell us that we're looking at two distinct species

of an order known as Hyaenodonta,

extinct, hypercarnivorous mammals

that lived on virtually every continent.

These animals varied widely in size and shape,

from 11 pounds to over 1,000.

The new skull represents an entirely new species

of Hyaenodon

that lived alongside Sekhmetops.

Following the tradition

of naming these ancient carnivores

after Egyptian deities,

this new species was named Bastetodon

in honor of Bastet,

the cat-headed goddess of protection and fertility.

Further analysis of the Sekhmetops

alongside the Bastetodon leads to a breakthrough.

When Sekhmetops was first discovered,

they originally placed the species

within a group of European Hyaenodons

and assumed that that's where Sekhmetops originated

before migrating to Africa.

But using the Bastetodon fossils,

that family tree has painted a very different picture.

The results of the analysis prove

that the opposite of what we once believed

was actually true.

Sekhmetops and the Bastetodon weren't European in origin.

They represented an entirely new group

of African Hyaenodons

that originated right where they were found, in Egypt.

Hyaenodons lasted as an order

for approximately 50 million years.

To survive that long,

they had to successfully survive

some of the Earth's most dramatic climactic changes.

[Teddy] One of these extreme changes

occurred around 34 million years ago,

when the planet began to cool.

Ice sheets expanded,

sea levels dropped,

and forests slowly transformed into grasslands.

Today, we know this period

as the Eocene-Oligocene boundary.

[Dr. Alison] This boundary is also known as the Grande Coupure,

or Big Break,

because of its devastating effects

on species across the world.

On the African and Arabian peninsulas alone,

approximately 60% of mammal species vanished,

but Hyaenodons survived,

with new species emerging in the wake of the disaster

and adapting to the changing environments.

[Dr. Dan] Throughout the Oligocene and the Miocene,

African Hyaenodons maintained their position

at the very top of the food chain.

And this was in part

because of their ability to adapt

and in some cases become supersized.

The global extinction of the Hyaenodons

remains an enduring mystery.

But some experts believe that the answer may lie

in dramatic environmental shifts.

During the Oligocene, about 26 million years ago,

tectonic shifts pushed the Arabian

and Eurasian plates closer together.

Over millions of years,

these shifts created new land bridges

for ancient species to spread between continents.

So creatures that were previously isolated in Europe

migrated south into Africa.

During the Miocene,

this faunal exchange really picked up,

and we start to see modern-looking predators

like cats, dogs, and hyenas appear on the African continent.

Unlike Hyaenodons,

these predators had flexible wrists and forearms

that allowed them to adopt new hunting techniques.

We now believe that these new predators

began to compete with Hyaenodons for prey.

The very same attributes that once made the Hyaenodon

so formidable may have accelerated its downfall.

Its dentition was extremely specialized,

and the predators' rigid bodies

meant that they relied almost exclusively

on their huge jaws and heads to bring down their prey.

When competition increased,

these animals may have been physically unable

to adapt to different food sources.

Eventually, they went extinct,

leaving cats and dogs

to take their place at the top of the food chain.

The exact cause of the Hyaenodon's extinction

remains a complex web of unanswered questions.

But with every new species that emerges,

our understanding of this ancient apex predator

grows a little clearer.