Original subtitles

Paris' Notre-Dame Cathedral suffers

a catastrophic fire, and restoration efforts reveal

something shocking hidden under its floor.

You can see human bones and hair

and textile remains.

Maybe clothing or a burial shroud?

The top of this person's skull has been sawed right off,

right across the forehead and around the back.

Record-breaking heat results in a severe drought

in the Canadian West, exposing a dark mystery.

There's a human skull,

as well as ribs and arm bones all scattered around the area.

At a depth of roughly a foot and a half,

an almost completely intact skeleton is revealed.

An ecological calamity 13,000 years ago

leads to the extinction of animal species

across the planet.

The impact of the disaster was devastating.

North America lost 70% of its large mammals,

known as megafauna.

Exactly how and why certain species survived

has been a source of fascination and debate

amongst palaeontologists for decades.

All over the world incredible discoveries

are being revealed by devastating events.

Floods, earthquakes,

droughts, hurricanes,

volcanic eruptions.

Trails of destruction expose extraordinary history.

This is Discovered by Disaster.

On April 15, 2019, Paris' famed Notre-Dame Cathedral,

a stunning example of Gothic architecture

dating to the 12th century,

became engulfed in flames.

Notre-Dame Cathedral's roof

is clad in lead, over 450 tons of it.

Now, this fire is so hot that that lead is burning,

being carried skyward in billows of yellow smoke,

and it's also raining down over the firefighters' helmets.

Barely an hour later, the iconic spire collapses,

crashing through the roof

and the cathedral's famous vaulted ceiling.

France's president promptly pledges

that Notre-Dame Cathedral will be rebuilt

more beautiful than before,

and that the job will be completed within five years.

But the problem is that the building's masonry

has suffered severe heat damage,

rendering the remaining structure unstable.

Restoration can't even start until it's made safe.

After over two years of painstaking work

ensuring that the cathedral was stable enough

to begin the restoration,

the project is finally set in motion.

Rebuilding the roof and installing a new spire

will require 100-foot-high scaffold,

weighing over 600 tons,

to be erected in the crossing of the transept.

Many Christian churches are laid out

essentially in the shape of a crucifix.

The crosspiece is called the transept.

The center, the crossing of the transept,

is an especially sacred area.

You can't put a scaffold there

unless you're sure the floor can take the weight.

Archaeologists are granted permission

to conduct an exploratory excavation

under a specific set of tiles,

to assess the ground's integrity.

As workers begin removing sand and lime from under the floor,

they make a startling discovery.

It's a head and a pair of hands,

but it's not a literal head and hands.

It's a statue of a man's head

and a pair of hands set together as though in prayer.

What is it doing here?

Hundreds more carved wood pieces turned up.

Hands, feet, faces, decorative shapes,

and carvings of plants.

None of these look like

they were just crammed in here, though.

These objects were placed here with care.

The exploratory dig faces a strict time limit.

The pieces are carefully set aside so work can proceed.

But then everything stops.

Four to six inches below

where the floor tiles had been,

there's a large metal box.

It's about six feet by a foot and a half,

and not that deep.

And it's completely sealed up.

It seems to have been warped by the weight

of the earth and stones pressing down on it.

And given the color and texture, it looks to be made of lead.

But what's inside it?

Fully uncovering the container reveals

this brass plate with a name on it.

"Antoine de la Porte."

And in French it says that Antoine de la Porte died

in his 83rd year on December 24, 1710.

This is a sarcophagus.

It's a coffin.

Burials in cathedrals, under the floor like this,

were actually practiced in Europe

throughout the medieval and modern periods.

The most sought-after placements were near the choir,

under the transept, just like this one.

But why make a coffin out of lead?

Nowadays the dangers of lead water pipes

and lead-based paints are well known.

But in medieval times, lead was a special substance.

When you burn lead, it leaves behind

a yellowish, ashy powder.

Hence, alchemists concluded,

there must be a way to turn lead into gold,

which gave lead a certain cachet.

Lead is also associated with transformation

and resurrection.

So it's perfect for transporting someone

on what would be their final journey.

So, wealthy people, members of the elite,

often had their coffins made of lead.

But was someone actually interred in this coffin?

And if so, who?

The attending archaeologists note

a small hole at one end of the sarcophagus

and use it to insert a flexible endoscopic camera,

similar to what doctors use

to see inside a patient's digestive tract.

You can see human bones and hair and textile remains.

Maybe clothing or a burial shroud?

There's tremendous potential here

to learn about medieval burial customs--

if permission can be gained

to actually open this sarcophagus up.

For now, all we've got to go on is this dated brass nameplate.

Who was Antoine de la Porte?

Historians consult the church's records

from the late 1600s and early 1700s.

The records are illuminating.

Antoine de la Porte was a canon,

which is a member of the clergy responsible for a cathedral.

Now, many of us, when we hear clergy,

might think of an ordained clerk

who lives for and serves the church,

but De la Porte was wealthy.

De la Porte gave lots of money

to Notre-Dame Cathedral, which would explain

how he got such a prestigious resting place.

At one point, he contributed funds for the renovation

of the cathedral's choir,

which included the removal of the rood screen.

The rood screen, or chancel screen,

was a feature of some churches

that separated the clergy from the congregation.

By the end of the 17th century, after the Counter-Reformation,

most churches had decided to remove their rood screens.

But Notre-Dame Cathedral hadn't done that yet.

Notre-Dame Cathedral was long overdue

to get with the times and have its rood screen dismantled,

when De la Porte offered up the money to have it done.

So those carved wood pieces

were probably parts of the rood screen.

And the way they were arranged around De la Porte's coffin,

it's now clear they were intended to form a kind of tomb.

In light of the archaeological discoveries,

a small extension of the timeframe is granted

for the exploratory excavation.

Now things get a little wild.

In that same small area under the crossing of the transept,

but a little further underground,

still only a few feet deep, another lead sarcophagus.

So, what's going on?

Were these two sarcophagi put here together?

This second sarcophagus

has no identifying nameplate, and it's of a different style.

It appears to have been molded closely

around its occupant's body.

By its different color,

it's clearly not the same alloy of lead.

And this is key, because it was buried deeper

than the first one, it may be quite a bit older.

This coffin also shows damage,

allowing archaeologists at the site

to insert their endoscopic camera in for a peek.

Again, there are bones visible,

but no hair can be seen.

But there is something the other sarcophagus doesn't have:

plants.

They around the head area and the abdomen.

So could they be for decoration?

Was this person a plant-lover?

A botanist perhaps?

The time allotted for the excavation expires

and no further extension is granted.

The sarcophagi are delivered to Toulouse University Hospital,

350 miles away, where they can be opened.

De la Porte's coffin confirms much of what archaeologists

had surmised, but offers surprises, as well.

The bones of the big toe on one of his feet

shows possible signs of gout,

which is an inflammatory arthritis

also known as the disease of kings.

All of this aligns with what we knew,

that he was wealthy and a member of the clergy.

De la Porte's teeth

are in remarkably great shape, though.

I mean, this guy was 83 years old, and it was the 1700s,

and somehow he still has great teeth.

Hats off to this man, because most 83-year-olds

in modern times can't do that.

The other, anonymous sarcophagus raises questions,

and eyebrows, from the moment it's opened.

The top of this person's skull

has been sawed right off,

right across the forehead and around the back.

They identify the plants in his coffin

as aromatic herbs, which were sometimes used in embalming.

And part of the embalming process was to remove the brain.

So, sawing the skull open.

Close examination of the leaves of the herbs

seems to confirm something for the archaeologists.

The man's chest also showed signs

of having been opened up after death,

which would also have been part of the process.

So, this person was embalmed!

But when?

Embalming did grow more common

after about the mid-16th century.

So that could be approximately when this person died.

This doesn't tell us how he died, though.

As archaeologists continue to study the skeleton,

they see that it contrasts in almost every way

to De la Porte's.

We know from the brass plate that De la Porte

lived into his 83rd year

and that he had great teeth right to the end.

This person died around the age of 30 years old,

and by then they'd already lost almost all of their teeth.

Examination of the inside of his skull

reveals the likely cause of death: chronic meningitis,

an inflammation of the layers of tissue

that cover the brain and spinal cord.

It would have been a painful end to his life.

There is one more remarkable aspect

to this person's skull: the shape.

This skull shows evidence of what's known

as intentional craniofacial remodeling.

A young child's skull, while still soft and growing,

would be wrapped with cloth to intentionally affect its shape;

another custom popular amongst the aristocracy.

And deformation of his pelvic bone

suggests he rode horses from childhood.

So it's possible he was a cavalier,

or in other words, a knight.

After two years of research,

scholars now think that the skeleton could be

Joachim du Bellay, a prominent French Renaissance poet

who died in 1560.

There are almost certainly more discoveries waiting to be made

under Notre-Dame Cathedral's floor.

Whatever's there has waited all this time.

It can probably wait a few hundred years more,

for the next opportunity,

hopefully under better circumstances.

In approximately 850 BCE, a fire tore

through a close-knit Bronze Age settlement

in what is now southeastern England,

forcing families to flee as their wood and grass homes

exploded into flames around them.

The Bronze Age is a really important

but very little understood period in our prehistory.

It's the time between the Stone Age and the Iron Age.

So, basically, how did we make that transformation

from Stonehenge to the Roman Empire?

With every new thing we learn about the Bronze Age,

the more we realize what a huge step forward it was.

But it's hard,

because aside from the bronze tools and weapons

that the age is named for,

so much of what humans made back then hasn't survived.

A few miles east

of present-day Peterborough, England,

an archaeologist acting on a local tip

visits a disused quarry known as Must Farm

and observes a handful of charred and rotting

wooden posts protruding from the ground.

Anybody else who had seen

these ugly old timbers sticking up probably assumed

that they were remnants from the quarry days.

Researchers from Cambridge University's

Archaeological Unit are summoned for a second opinion.

More posts are uncovered.

It looks like the remains of a structure.

But what was it and who built it?

A dendrochronological analysis

of at least one of these posts

determines the oak tree it came from

was felled between 1290 and 1247 BCE.

That's during the Middle Bronze Age!

So there is something to this find.

This whole area was a very different environment

until it was drained and converted to farmland

four centuries ago.

Before that, it was in its natural state, a fen;

an ancient, watery marshland

supporting all kinds of creatures and humans.

Scattered around were human bones

and a number of intentionally broken artifacts.

Personal items like jewelry and weapons

were smashed and tossed into the water.

As the excavation at Must Farm expands,

the support posts of not one but four round structures

come to light.

The largest would have covered an area

of around 500 square feet, about the size of a small apartment.

And there's also one smaller, rectangular structure.

All these platforms were originally

perhaps six or seven feet above the riverbed.

There's also evidence of what looks like

a raised walkway connecting them.

Broadening their investigation,

the archaeologists discover dozens of artifacts.

Many of the artifacts found at Must Farm are unbroken

and in remarkable condition.

There are clay pots, remains of wooden buckets, and bronze axes,

even with portions of their wooden handles.

The presence of these intact artifacts tells us

that this was not a place for the dead;

it was a place for the living.

These weren't funeral platforms; they were houses.

This place carries the echoes of daily life.

A pottery bowl still holding parts of a meal:

wheat grain porridge mixed with animal fat.

A wooden spatula rests against the inside of the bowl.

Around the round houses,

a row of ash wood posts, forming a palisade,

a protective fence or wall, is discovered.

But the palisade doesn't run

all the way around the houses.

It seems to form half of a rough oval, and then stops.

The ends of that oval shape are right up against

the edge of where the old clay quarry was.

So basically, when the quarry was active

during the 1960s and '70s, roughly half of the settlement,

including the rest of that palisade,

was unknowingly torn away.

Surveying the scene, the team notices

what appear to be roof timbers radiating out from the center.

But strangely, these roofs are sitting flat down

over the bottoms of the support posts,

as though they had collapsed straight down.

Parts of these roof timbers had clearly been

subjected to intense heat at some point.

And that's when the realization comes

that this settlement burned down,

that these houses were destroyed in a catastrophic fire.

The roofs were thatched out of three layers--

straw, turf and clay-- to make them rainproof.

That would have made them extremely heavy.

So once those oak support posts

had been compromised by the fire,

the roof would have come down and pancaked everything,

walls, floors, and all the contents inside those homes,

straight down into the water.

The moment those heavy roofs collapsed into the water,

the fire was instantly extinguished.

So, much of the material did not burn completely.

The fire that destroyed this settlement

also helped preserve it.

But what caused it?

Soot deposits are found

on parts of the surviving structures,

confirming the presence of hearths or cooking fires.

Because there's soot

only on the largely unburned roof timbers,

it's clear that those areas aren't where the fire started.

That doesn't mean the cause wasn't a cooking fire;

there's just no conclusive evidence that it was.

As carbon-dating results come in,

the archaeologists get some surprising information.

The ash posts from the palisade

yield a date range between 1000 and 800 BCE.

Now that's a lot later than the initial dating

of the houses' support posts.

Those results came back as between 1290 and 1247 BCE.

So after hundreds of years of being fine

without any protective enclosure,

did some threat suddenly make the inhabitants feel

they had to make one?

What's also interesting is that there are

scattered ash wood chips

left over from the construction of the palisade.

These chips are unburned, of course,

because they had always been underwater.

But the debris from the fire lies directly on top of them.

So the fire occurred soon after the palisade was built,

which begs the question,

was the fire the result of an enemy attack?

Further excavations at the Must Farm site

reveal a treasure trove

of well-preserved tools and weapons.

There are bronze sickles for cultivating grasses

or crops, bronze axes and curved gouges for shaping wood.

There's a stack of bronze-tipped spears

with shafts over 11 feet long in one of the houses,

and bronze swords with their edges still sharp.

Now we know that during the Bronze Age,

the human population grew, increasing competition,

and therefore violence increased overall.

So it's entirely possible

that the settlement was burnt to the ground by outsiders.

But why?

One possible reason could be simple envy.

You might call the people who lived at Must Farm well off,

in relative terms.

Among the vessels found at the site are these fine, tiny cups.

It's beautiful, detailed work,

just to make something more enjoyable to use.

This wasn't minimal, subsistence living,

so maybe this community was the envy of all others in this area.

As the team continues to investigate the settlement,

more details about the lifestyle

of its inhabitants emerge.

One of the most stunning finds

is a range of finely woven textiles,

again, miraculously preserved by the combination

of surface carbonization from the fire

and then being buried deep in the clay silt.

Clearly there's a high level

of skill and artistry involved here.

There's also a tiny, charred ball of flax thread.

with strands just 1/50 of an inch thick

that has survived three millennia in the mud.

And more than that,

elements of the whole textile-making process are here,

including part of a spindle and clay weights from a loom.

And a beautiful necklace

with beads of glass, amber, and siltstone was also found.

Isotope testing determines that the beads

came from as far away as Denmark,

400 miles across the North Sea, and Iran.

Via the waters of the fen,

boats carrying goods for trade would not only have been able

to travel between here and the North Sea,

but also to the rest of the known world.

That access to goods from faraway lands might have been

one of the reasons why this area was chosen for the settlement.

And also why others would have envied the people

who lived in those houses.

But we still can't say for certain that the settlement

was burned down by jealous neighbors.

When further detailed dating analysis

of more of the wooden posts comes back,

a pattern emerges-- one that changes

archaeologists' views of the site yet again.

It becomes clear that there are two eras

of support posts within this site.

Some posts are from an older causeway

that predates the settlement structures.

Those are the ones that were dated

during the initial excavation

and determined to be from between 1290 and 1247 BCE.

At first it wasn't clear those were from an older causeway.

They appeared to be part of these round house structures.

So the causeway was actually built first.

Three centuries later,

that causeway had fallen out of use,

and the tops of its posts would have been gone,

completely rotted away.

And then the second group of posts went in,

the supports for this round house settlement,

which was built overtop of the remains of the old causeway.

The bottom line is, this intermingling

of older and newer posts at the site

led to an initial misunderstanding

of the relative ages of the structures here.

We now understand that the Must Farm settlement

and its protective palisade

weren't built over 300 years apart,

as it originally appeared.

They were actually built at the same time.

What this means is there was no sudden need

for extra security, centuries after the settlement was built.

The need was felt from the start,

when the settlement was established, about 850 BCE.

These were clearly extremely dangerous times.

The new data also solves another mystery

that's been troubling researchers.

There's no evidence of wood-boring beetles

in the oak supports.

And you'd expect to see some.

Now we know why: The bugs never had the chance to move in.

The settlement was new.

It might only have been here for nine months or maybe a year

before the fire destroyed it.

As for what caused that fire,

and where the families who fled from it ended up,

we still don't know.

The Must Farm site is the largest assemblage

of domestic material ever recorded

from a Late Bronze Age site in Great Britain.

Its destruction by fire captured a moment in time,

a virtual snapshot of Late Bronze Age life and culture.

During the summer of 2015,

record-breaking heat roasted the Canadian west.

The provinces of Saskatchewan, Alberta and British Columbia

were severely hit.

Over the four months,

wildfires were burning at an unprecedented rate.

By the end of summer,

fires had burned up an area the size of Sicily.

Thousands of people were evacuated

from their homes and communities.

Because resources were stretched to the limit,

the Canadian military had to be called in

and international aid mobilized.

Water restrictions were put in place

to reduce consumption.

That, combined with the raging fires,

heavily impacted farmers' crop yields.

Even if their fields didn't burn,

they still couldn't water them properly.

Late in August, on a farm close to Viking, Alberta,

a farmer was surveying his devastated crops

when he came upon a badger digging around in his field.

The animal had exposed something

completely unexpected.

There's a human skull as well as ribs and arm bones

all scattered around the area.

There's also a glass bead lying with the bones.

Now, this farm has been in operation since 1937,

and there's never been any sign of a burial on that property

over those eight decades.

So who's buried here?

Because of the possibility

that it could be a crime scene,

the police were initially called in to investigate,

but they quickly concluded that no crime had taken place.

They passed the case on

to the office of the chief medical examiner.

The farmer's family had been working this land

for most of the 20th century.

But before it became farmland,

Indigenous communities had been calling this area home

for thousands of years.

So there was a good chance that the remains

were of an Indigenous person.

The colonization of Canada was carried out

in part through the signing of treaties between the government

and the Indigenous nations that populated the country.

In 1876, leaders of the Cree, Assiniboine and Ojibwe people

signed Treaty 6 with the Canadian government

and relinquished 121,000 square miles of land,

an area about the size of Germany.

A year later, Treaty 7 was signed by representatives

of the Blackfoot people, who occupied an area

of around 50,000 square miles in southern Alberta.

On paper, these treaties guaranteed

Indigenous populations reserves, annual payments,

and the continued right to hunt and fish on public lands

in exchange for the title to that very land.

In reality, the treaties signed in good faith

by Indigenous representatives across the country

never provided what they were meant to guarantee.

In effect, they were just huge land surrenders

on this enormous scale,

with the obligations that were set out on paper

for the Canadian government never being met,

even to this day.

Although some of the bones had been disinterred

by the badger, it was uncertain

where the site of the actual burial was.

So the team uses metal detectors

and eventually gets a hit.

At a depth of roughly a foot and a half,

an almost completely intact skeleton is revealed.

The pelvis has a wide and rounded shape,

indicating that this is a female.

Because of the badger's activity,

some vertebrae and other bones are missing,

so her size can't be determined by measuring the skeleton.

To determine the height of an individual,

scientists use the size of the femur

and work off a four-to-one ratio.

A femur is usually around 25% the size of an entire human,

and in this case, her femur is around 16 inches,

so she probably measured around five-foot-two.

With a height like this, it's hard to know right off the bat

if she was young or an adult when she passed away.

But she does have all her adult teeth,

meaning she's not a child.

But other than teeth, there is another way of determining age

by looking at a specific part of our bones.

Human long bones, like the femur and humerus,

have something called the epiphyseal plate,

otherwise known as a growth plate.

This is a piece of cartilage that exists in the bone

when humans are growing.

When this cartilage has turned to bone,

it's an indicator that the bone has reached maturity.

The stage of closure of this young girl's growth plates

indicates she was around 13 or 14 years of age

when she passed away.

As the analysis continues,

cavitation is discovered on parts of her vertebrae.

These are little holes, or parts of bone that have died.

And there are also signs in her shoulders

that the bone has eroded.

People lived hard, active lives back then.

But this woman was young,

so something else must have been going on.

It could be the result of brucellosis,

a bacterial infection known to damage bone in this manner.

It's a chronic infection of the lungs and also presents symptoms

that include things like joint and muscle pain,

fevers and sweating.

But whether or not this young woman died

as a result of brucellosis, we can't say,

though her quality of life would have been severely impacted.

Continuing with the excavation,

4,500 glass beads are recovered from the grave.

The beads are spherical,

and almost all of them are white,

except for 57 of them, which are turquoise.

Many of those beads are found next to her left wrist.

So it's probably true that she was wearing a bracelet

on her left arm when she was laid to rest.

There are also larger glass beads of varying size,

shape, and color found lying around her neck.

Some are barrel-shaped and turquoise,

others are medium-sized and spherical,

and there are two amber-colored ones that are hexagonal.

They likely formed part of a necklace.

The beads were produced in Europe

and shipped across the Atlantic for use by fur traders

in their dealings with Indigenous groups across Canada.

They were highly valued and traded

among Indigenous populations all across North America.

Along with the glass beads,

31 metal buttons were discovered among the remains,

most of which had a thick, black, felt-like fabric

still attached to them.

They're almost all identical--

flat, round, and made of brass.

Most of them were lying around her midriff,

while another five are found towards the end of her left arm,

close to the hand.

You can tell by the uniformity of these buttons

that they were made by some industrialized process.

So where did they come from?

Similar buttons have been found

at other trading posts in Alberta.

Archaeologists have found similar styles of buttons

at Fort George on the North Saskatchewan River

and Fort Dunvegan on the Peace River.

Both of these forts

began operating in the late 18th and early 19th centuries.

So these buttons are probably from around that same time.

But considering where they're located next to her hand,

is it fair to say they're part of a cuff?

Traders would often give gifts

that would recognize their social status or position

as leaders within their community.

Exchanging gifts was a very important practice.

It was a sign of an individual's generosity,

but it was also a way of establishing

a working relationship based on trust,

which could be the basis of future trade.

Along with the remains,

archaeologists also found a thimble and brass finger rings.

The thimble in particular can be seen

in old photographs of Blackfoot and Cree peoples.

It was sometimes used for adornment.

The girl's remains were found in an area

that in the 18th and 19th centuries

was largely occupied by the Blackfoot,

a confederacy of three

culturally and linguistically related peoples.

This location is more or less

between two trading posts,

so it could be that she was on her way to or from one of them

when she died.

She was laid to rest with a lot of thoughtfulness

and care, so she must have been traveling with a larger group.

But whether or not they were Blackfoot is hard to say.

Both Beaver and Cree groups occupied areas

to the north and east of the burial site,

so she could have been from one of those communities as well.

It has not been possible to identify

to what specific people the girl belonged to,

but in a sign of respect,

she is referred to as "our grandmother"

by both Treaty 6 and 7 representatives.

13,000 years ago, a combination of human-ignited fires,

climate change and a massive drought

destabilized the Earth's ecosystems

and led to the extinction of animal species

across the planet.

This ecological disaster occurred in the Pleistocene Era,

which spanned from 2.6 million years ago

to roughly 10,000 years ago.

The era was marked by several glacial periods, or Ice Ages,

not to mention the arrival of humans.

The impact of the disaster was devastating.

It disrupted the Earth's ecology,

and the shifts in climate and environment

were too fast for many animals to adapt,

particularly herbivores.

There was extinction on every continent,

but some areas were hit harder than others.

North America lost 70% of its large mammals,

known as megafauna.

Mammoths, mastodons, western camels,

ground sloths, giant armadillos.

I mean, those are just some of the species

that vanished from the Earth.

Not to mention

all the carnivorous animals that preyed on those things

like sabre-toothed cats and dire wolves.

So you've got entire food webs that are just scrambled.

While this event wiped out some wildlife for good,

many animals, such as coyotes, bison and mountain lions,

survived the extinction.

Exactly how and why certain species survived

has been a source of fascination and debate

amongst palaeontologists for decades.

Researchers studying the mass extinction event

notice a geographical trend that may provide some answers.

North and South American species became extinct

at a much higher rate than animals in Europe and Asia.

So, is it possible that geography played a role?

Was the Eurasian ecosystem populated with animals

that were somehow heartier, stronger or faster?

A closer look suggests there's more to it than that.

Specifically, the impact of humans arriving on the scene

and hunting for prey.

Now, many North American mammal species

weren't used to being hunted and colonized.

They were animals that had evolved in isolation,

away from humans.

In Europe and Asia, a larger percentage of mammals

had evolved alongside humans,

and so they were more accustomed to being hunted.

So the extinction rates were lower in that time period,

probably because there were big extinctions,

they were just a lot earlier on.

But human colonization is only one part of the story.

It still doesn't explain the survival of one species

over another in the same location.

For example, why did the coyote of the Southwestern US

survive the disaster,

while his larger neighbor, the sabre-toothed cat, did not?

Hoping to solve the mystery,

the researchers conduct a study of extinct animal fossils

discovered in the La Brea Tar Pits

in Los Angeles, California.

The La Brea Tar Pits are these ancient pools

of thick, sticky asphalt that has oozed to the surface

from large petroleum reservoirs.

When crude oil seeps to the surface

through cracks or fissures in the earth,

the lighter portion of the oil evaporates,

and so what's left behind is a heavy, tar-like substance.

Asphalt from the area

was used for thousands of years

by local Native Americans as a powerful glue

and as waterproof caulking for baskets and canoes.

After the arrival of Westerners, the asphalt was mined

and used for roofing by inhabitants of the nearby town

that would later become LA.

What's remarkable about the Le Brea Tar Pits,

in addition to their consistency, is their longevity.

Those pools have just been sitting there

for thousands of years.

And so in the last couple of centuries,

they have been a very exciting place

for evolutionary biologists.

The tar pits were discovered to contain

animal fossils from as far back as 40,000 years ago

until about 8,000 years ago,

a timeframe that includes the ecological disaster

and resulting extinction.

So is the answer to how and why various species survived

hidden in the sticky asphalt of the Le Brea Tar Pits?

To date, researchers have discovered evidence

of at least 59 species of mammals in the tar pits.

Mammoths, American lions, short-faced bears.

It's basically a massive prehistoric gravesite!

And this is because, going back almost 50,000 years,

the tar pits behaved as a kind death trap,

by trapping an estimated 10,000 animals.

Herbivores would get stuck in the tar

and attract carnivores with their struggle or decay.

Carnivores would then attempt to feed on them

and become stuck themselves,

creating a seemingly endless cycle of death.

The asphalt is sticky

thanks to its unique composition,

which means the fossils are extremely well-preserved.

And we're not talking about a handful of specimens;

over a million fossils have been collected.

It's a lot to process, but the abundance of data

allows scientists to examine

the patterns of extinction in detail.

The researchers focus their attention

on one surviving species in particular: the coyote.

Coyotes were the third most abundant mammal

discovered at the site.

But unlike their larger competitors

like dire wolves or American lions,

common coyotes are still seen in Los Angeles today,

so they are a direct link to their ancestors.

The most obvious difference is size.

Pleistocene coyotes weighed between 35 to 55 pounds

and overlapped in sheer size with wolves.

But today the upper limit of the coyote

is only 25 to 39 pounds.

So it might be possible that the coyote

got smaller and smaller over time

as an adaptive response

to the disappearing prey and food scarcity.

After all, smaller animals need fewer calories to survive.

But that doesn't account for the fact

that other much larger Ice Age animals survived,

and in some cases, thrived.

If you look in Alaska, enormous wild bison and moose

actually increased in numbers.

So there's more at play here than size alone.

The researchers look to the possibility

of competition among Ice Age animals.

If we assume that all carnivorous predators

were competing for the same food source,

maybe coyotes somehow won the competition

over, say, sabre-toothed cats or dire wolves.

They discovered that the cat family predators

mostly lived in forested ecosystems,

likely using the foliage as a cover

to ambush and pounce on the unsuspecting prey.

Whereas the Pleistocene dog predators,

which includes the coyote,

were much more likely to hunt for prey

in open grassland areas.

So in this case, competition was not the deciding factor

for the coyote's survival.

Tooth enamel analysis leads the researchers

to discover another possible explanation--

the coyote's ability to change its diet over time.

You look at coyotes today,

they're almost perfect Darwinian specimens

with remarkable survival skills.

They can hunt in packs as well as individually;

they're incredibly resilient;

and they've adapted to urban environments

despite human efforts to eradicate them.

So what if the secret to surviving this natural disaster

13,000 years ago

is the very same thing that has allowed them

to thrive today-- adaptable food selection?

The results of the dental analysis reveal

that before the extinction period,

the coyote's diet consisted mostly of megafauna animals,

the large herbivores.

But as these massive animals slowly disappeared,

the coyote looks like it shifted

to eating smaller mammals as well as scavenging on carcasses.

The survival skills and instincts of today's coyote

go back hundreds of thousands of years.

They're highly opportunistic, and it's served them well.

They can eat plants, flesh, scavenge through garbage,

a whole variety of food.

And it's the extinction event that forced them to adapt

even as their initial food source had vanished.

The research conducted

at the La Brea Tar Pits revealed fascinating truths

about one animal's capacity to adapt

and proved that every once in a while

a species' will to live can surpass the odds

and surprise us all.