Original subtitles

Narrator: In the Swiss Alps, archaeologists discover

a treasure trove of ancient artifacts.

Dr. Riskin: 12 inches below the surface is this object.

It's so rusted that its shape is distorted,

but you can still tell exactly what it is. It is a knife.

Anthea Nardi: It appears as if it's double bladed,

so if it wasn't made for practical purposes,

could it have had a more sinister purpose?

Narrator: In Canada's high Arctic, strange items

reignite a 100 year-old mystery.

Dr. Agbedor: They find a tin of unopened food,

and an enamelled metal plate and cup.

Not exactly the kind of items you'd expect to find

in a desolate Arctic island.

James Ellis: But if it was a campsite,

you'd expect to find remnants of a fire, maybe food waste,

yet nothing like that was discovered.

It's very odd.

Narrator: Archaeologists conducting research high

in the Peruvian Andes stumble on something unexpected.

Dr. Leonard: They notice points and shards that look like

ancient tools made by early tool makers.

Dr. Cantor: But this area is extremely inhospitable.

So who were these people, and could they have survived

in this environment?

♪ [show theme music]

Narator: These are the strangest mysteries,

trapped in the coldest places.

♪♪

Lost relics.

♪♪

Forgotten treasures.

♪♪

Dark secrets.

♪♪

Locked in their icy tombs for ages.

♪♪

But now, as ice melts around the world,

♪♪

their stories will finally be exposed.

♪♪

♪♪

Narrator: The Alps see some of the fiercest weather

on the European continent.

Although their location is not very far north

in terms of latitude, their altitude

guarantees a steady supply of snow, wind,

ice and subzero temperatures.

Dr. Leonard: The Alps are an enormous mountain range

and stretch across the borders of several European nations,

however, only Switzerland and Austria

are considered truly Alpine nations,

because the mountains cover so much of these two countries.

Dr. Cantor: In Switzerland, you're either in the Alps

or in the foothills of the Alps.

And even if you're in the foothills,

you're at a pretty high elevation because the peaks

of the Swiss Alps frequently reach over 13,000 feet.

Narrator: In 2019, an amateur archaeologist searching an area

close to Crap-Ses in the alpine foothills

of southeastern Switzerland,

heard a faint signal from his metal detector,

indicating that a metal object lay buried beneath.

Dr. Riskin: 12 inches below the surface is this object.

It's so rusted that its shape is distorted,

but you can still tell exactly what it is. It is a knife.

Anthea Nardi: Because it's so heavily rusted,

it's hard to determine what kind of knife this is,

or where it's from.

But its shape is very different from your regular knife.

It appears as if it's double bladed,

so if it wasn't made for practical purposes,

could it have had a more sinister purpose?

Narrator: The knife is sent to a lab for analysis,

where state of the art techniques are used

to remove the rusted, corroded metal

revealing that it has a broad blade

and a very distinct horizontal pommel on the hilt.

Dr. Leonard: This isn't a knife at all!

This is a dagger, a pugio!

A sidearm that many of the soldiers of ancient Rome

wore at their waists!

But how did it get here?

Did some Roman soldier simply drop it on his travels?

Narrator: Curious whether the pugio could lead to more

ancient artifacts, professional archaeologists decide

to properly excavate the site and its surroundings.

Owing to the size of the area,

they enlist the help of the public,

who scour 370,000 square feet

with their metal detectors.

Almost immediately, they begin sounding off.

Dr. Cantor: Dispersed across this area

are several intact spears.

They're made of iron and have a triangular head

and a long narrow shaft.

Considering the discovery of the pugio,

these must be the remains of the Roman pila!

Dr. Riskin: Pila is a Latin word and it's the plural for pilum...

And a pilum is this 7 foot long javelin, basically,

that was used by soldiers in ancient Rome.

So the legionaries would use these things in battle,

they could stab with it, they could throw it,

And importantly, like the pugio,

they were also standard issue!

Anthea Nardi: Considering all of the artifacts,

and remains of their standard-issue shoes,

there was definitely some form of military activity

going on here, the dagger couldn't simply have been lost.

No evidence of a battle involving ancient Rome

has ever been found on Swiss soil,

but perhaps this could be the first?

Narrator: As the excavations continue,

hundreds of little lead pieces emerge from the soil.

Dr. Leonard: These little lead pieces are interesting.

They're all lozenge shaped,

they have a standardised length of one to one and a half inches

and they have weight of around 1 to 2 ounces.

And what's strange is that they have letters

stamped on the back.

What are these things?

Dr. Riskin: But on these ones in Switzerland,

it's not letters or names.

It's Roman numerals, and it's the Roman numerals for three,

for ten and for twelve,

that are written on the side

Narrator: One of the lozenge shaped lead pieces carries

a peculiar crack down the middle.

Anthea Nardi: This long slit is evidence

of high velocity impact!

Meaning that many of these things were flying through

the air at great speeds.

The only way for that to happen would be to fire them

from something like a slingshot,

which leads us to the conclusion that

what we're looking at here are slingshot bullets!

Dr. Leonard: So we can deduce that the numeral X

on the lead bullet means

that this was a bullet made for the 10th legion,

the XII for the 12th legion and so on.

This is pretty amazing!

It would be the equivalent of having bullets cast

exclusively for a modern day army division!

Dr. Cantor: These slingshots packed a nasty punch.

Recent experiments have demonstrated

that they were almost as strong as a bullet fired

by a .44 Magnum!

The question is, who was on the receiving end of the bullets

discovered in the Swiss Alps?

Narrator: As excavations continue,

more ancient weaponry is unearthed.

Dr. Riskin: One of these weapons is an iron ring,

with six spikes sticking out of it.

And that was probably part of a flail.

Dr. Leonard: The Rhaetians were a collection of several

different tribes occupying Europe's Alpine region

before the Roman conquest.

Although they were culturally different and lived in an area

spanning parts of today's Austria,

Germany and Switzerland,

they shared both cultural and linguistic traits.

Dr. Cantor: Not too far away in France,

there's an old Roman monument called the Tropaeum Alpium,

this translates as the Trophy of the Alps,

and it was built to celebrate the Roman victory

over all of Europe's 45 Alpine tribes!

On it is clearly written the name Suanetes,

one of several Rhaetian tribes.

We know that they were living in today's

southeastern Switzerland,

right in the path of an invading Roman army.

Narrator: The Tropaeum Alpium was specifically dedicated

to the Emperor Augustus' victory.

He reigned for 45 years starting in 31 BCE,

and is credited with ushering in the golden age

of the Roman Empire, in part made possible by their conquest

of the tribes residing in and around the Alps.

Dr. Riskin: So all these artifacts have to be the remains

of a battle fought between the Suanetes and the Romans.

And that makes it a very rare find.

This is definitely the first time we've seen

anything like this in Switzerland.

Anthea Nardi: But they were a long way from Rome,

and overseeing a military campaign in difficult terrain,

so far from their homeland, was no small feat.

So how did they do it?

Narrator: 15 miles south of the battle site at Crap-Ses,

at an elevation of 7,500 feet,

is the Septimer Pass.

Yet another amateur archaeologist is surveying

the site with his metal detector

when it begins ringing.

Dr. Leonard: In an area measuring 430 square feet,

about the size of a one bedroom apartment,

more slingshot lead comes to light.

Again, they're stamped with the numerals of the Roman third

and twelfth legion, indicating that these legions

entered Switzerland by this route and went on

to fight the Suanetes further down the valley!

Narrator: Taking over from the amateur archaeologists,

professionals arrive at the Septimer Pass,

to conduct a proper excavation.

They find several pointed iron pegs,

with an eyelet attached to the top.

Dr. Cantor: At the top of these pegs, there is evidence

that they have been flattened with a hammer.

And it's really not too hard to say what these pegs were for,

because their design hasn't changed much

in the last 2,000 years.

You can still find them at every camping store,

they're tent pegs!

Dr. Riskin: This means that the Roman legionaries

were camped out here!

Men from the 3rd, the 10th and the 12th legions

were probably stationed here, not just on their way

down the valley to go fight the Suanetes,

but also as a place to stay, and observe and control

who could make the journey across the Alps!

Dr. Leonard: The legionnaires stationed at the pass

were a vital segment in a military supply chain,

that stretched from the Swiss valleys and beyond,

all the way back to Rome.

So from a strategic point of view, occupying this pass,

at least during the months when it was actually passable,

would have been essential to the Romans.

It provided them with the logistical capacity

to strike out further, into unconquered territory.

Following their defeat of the Rhaetian tribes,

the Romans moved swiftly north,

conquering most of the European continent

as far north as the Rhine River.

♪♪

Narrator: In Canada's foreboding high Arctic

lies Axel Heiberg Island,

a frozen, uninhabited expanse of land

just 750 miles from the North Pole.

Dr. Riskin: Axel Heiberg is Canada's second northernmost

island, and it's the 32nd largest island in the world.

It's about the same size as Switzerland.

J. Ellis: It's a frigid place, with average temperatures

of almost -33 degrees Fahrenheit in January.

Around 35 percent of the island

is permanently covered in ice,

and the rest of it is mostly just bare ground,

with little to no vegetation to speak of.

Dr. Cantor: I can give you a sense of just how frozen

the ground is on Axel Heiberg.

During the 1970s, oil and gas companies did some

exploratory drilling there, to see if there were

any deposits worth pursuing.

They found that the permafrost was almost

1,600 feet thick in some places!

Narrator: A three-person research team is conducting

surveys of Axel Heiberg Island's southern shoreline

between Cape Southwest and the mouth of Surprise Fiord,

when they come across some curious items,

on the barren landscape.

Dr. Agbedor: They find a tin of unopened food,

and an enamelled metal plate and cup.

Not exactly the kind of items you'd expect to find

in a desolate Arctic island,

and from the condition that they're in,

it looks as though they've been here for a long time,

possibly even several decades.

So how did they get here?

James Ellis: Leaving behind caches of food

was a common practice among Arctic Explorers,

both the early pioneers

and into the mid-twentieth century.

In case of emergencies, they would stash supplies

along their return route,

but sometimes they never made it back to use them.

Dr. Riskin: Tinned food was a staple on even the earliest

Arctic expeditions, including one of the most famous

ill-fated journeys of them all:

the doomed Franklin Expedition.

Narrator: In May of 1845,

Sir John Franklin and his crew

of 24 officers and 110 men aboard two ships,

HMS Erebus and the HMS Terror

set sail from London in the hope of finding

an easier trade route to Asia,

across the North American continent.

They were spotted in the Canadian Arctic

by a whaling crew sometime in late July.

The expedition continued westwards and then disappeared.

Dr. Agbedor: In 1850, a search party

that was trying to locate Franklin and his men,

came across the graves of three members of the crew

on Beechey Island, which is just under 250 miles

from Axel Heiberg Island.

They also found hundreds of empty tin cans,

that once contained preserved meat.

So, could the tin food can discovered

on Axel Heiberg Island be connected

to the Franklin expedition?

Dr. Cantor: Many things about Franklin's trip

are still shrouded in mystery and lots of questions remain,

but most historians believe that he never ventured

as far north as Axel Heiberg Island.

Narrator: Exploring the area further,

the researchers discover more strange items,

that only serve to deepen the mystery.

Dr. Agbedor: There's a heavy two-gallon canister

with a cork stopper, likely used for carrying fuel.

And nearby, what looks like a tattered piece of canvas,

possibly what's left of a tent,

is also found partially buried in the ground.

It looks like this could be the remains of a campsite,

and whoever was here seems to have left in a hurry.

James Ellis: But if it was a campsite,

you'd expect to find certain things to indicate

that they may have stayed here for some time,

remnants of a fire, maybe food waste,

yet nothing like that was discovered. It's very odd.

Narrator: Not far from the canister and canvas,

something else catches the researchers' eyes.

Dr. Riskin: There's this small pile of rocks

that looks totally unnatural,

It's like somebody put it here for a reason.

And if you look among those rocks,

you find fossils,

and you find this one really nice mineral sample

that looks like it might be gypsum crystal.

It looks like, whoever was here

was doing some kind of a geological study.

But who was it, and when was it?

Narrator: Axel Heiberg Island was first sighted in 1899

during a Norwegian Arctic expedition led by Otto Sverdrup,

and named for the voyage's sponsor.

Dr. Cantor: Beyond exploration, there was also a

scientific purpose to Sverdrup's expedition.

They recorded data about ice, temperature,

and the earth's magnetism.

And collected thousands of plant and small animal specimens,

along with rock and fossil samples.

We know that Sverdrup and his men explored Axel Heiberg Island

and given the geological specimens found at our site,

is it possible that these things were left here

by the Norwegians?

Dr. Riskin: Maybe. But, it looks like

whoever was on Axel Heiberg left quickly,

like they were under duress or something.

Something bad was about to happen

and they had to take off quickly.

Thing is, there are no records

to indicate that Sverdrup and his men

ever encountered anything on this island,

that would have caused them to abandon a campsite

at the drop of a hat.

Narrator: As the researchers continue to search the site

for more clues, they come across two more items

that may help them put the pieces of the puzzle together.

James Ellis: Slightly settled in the dirt,

there's a pretty large wooden box.

Inside is an antique surveying instrument called a transit.

These devices used small telescopes to measure

horizontal and vertical angles to map elevation.

And about 15 feet away, almost completely buried

is an old compass lying face up.

Narrator: The two instruments are removed from the site

for analysis and are found to contain

some interesting details.

Dr. Cantor: The transit is engraved with the name

of the company that manufactured it.

"Max Hildebrand fr üher August Lingke u. Comp.

G.m.b.H. Freiberg Sachsen",

which translates to "Max Hildebrand, formerly

August Lingke and Company, Ltd., Freiberg, Saxony".

Dr. Agbedor: Hildebrand was a German mechanic and entrepreneur

who specialized in the design and construction

of surveying equipment.

In 1873, he moved to Freiberg and joined a precision

engineering business called "August Lingke & Compagnie",

which later became Hildebrand and Schramm.

James Ellis: The compass doesn't bear Hildebrand's name,

but the finish and patina are very similar

to that of the transit.

And when the instruments were observed closely,

it was found that the compass could be rested on protrusions

from the side of the transit.

Furthermore, the compass also had a pin

that fit a hole on the transit,

meaning, the two devices were designed to work in conjunction.

Dr. Cantor: In 1921, Hildebrand's firm merged

with the Berlin-based Wichmann Brothers,

and after that, the company was known as

the Hildebrand-Wichmann-Werke.

So this means that these instruments were made

in Freiberg sometime between the 1880s and 1921.

Narrator: The researchers on Axel Heiberg Island

are preparing to leave the site,

satisfied that they've found everything there is to find,

when they come across something that had gone overlooked.

Dr. Riskin: It must have been blown away at some point

because it's really far from the other items

and it's almost entirely buried in sand.

But they find a piece of clothing.

Maybe it's a shirt, maybe it's part of the underwear.

It has wooden buttons. And amazingly,

there's still a label attached to the collar of it.

And the writing on that label is in German.

James Ellis: So we've got German-made surveying equipment

and German-made clothing.

I think it's reasonable to assume that whoever left

these things here was probably from Germany,

which likely means one thing,

that this might be the last known camp

of Hans Kruger and his team.

Narrator: Born in Prussia in 1886,

Hans Kruger trained as a lawyer,

but eventually became involved in mining,

and settled in what is now Namibia.

After World War I, he returned to Germany to study geology

and began planning a scientific Arctic expedition.

Dr. Cantor: Details are scant, but what we do know,

is that in the spring of 1930,

Kruger and two associates departed from Bache Peninsula

on Ellesmere Island, and were accompanied by a supply team

as far as the western side of the island.

They then set off alone, heading north through Eureka Sound,

and were never heard from again.

Dr. Agbedor: When the three men failed to return that year

to Bache Peninsula, or another base

at Dundas Harbour on Devon Island,

the Royal Canadian Mounted Police launched

a search patrol in the spring of 1931.

But bad weather conditions prevented them

from reaching Axel Heiberg Island.

Several other searches were mounted in the following years,

but the men's fate ultimately eluded the authorities.

J. Ellis: Traces of the expedition were

subsequently found, and their path was documented

from Ellesmere to northernmost Axel Heiberg Island.

From there, they progressed to their final known landfall

on Meighen Island, the outermost island

in the polar continental shelf,

and this is where the trail went cold.

Narrator: Initially, observers believed that Kr üger

and his companions perished somewhere on the sea ice

between Meighen Island and Amund Ringnes Island,

thought to be their next destination.

Dr. Riskin: The prevalent thinking has been

that they probably lost their sledge.

Maybe it plunged through thin ice and then they died

because of exposure or starvation.

But what we now know because of this site, is that they made it

to the southern tip of Axel Heiberg Island.

Now, whether or not that was their final campsite,

that's still up for debate.

Dr. Agbedor: Some people believe that they did in fact stay there

for an extended period, but abandoned the site under duress.

The fact that so few provisions remained,

and that their tent had been destroyed,

suggests that the three men had experienced

a late spring snowstorm that buried everything,

and they had no time to dig things out before escaping.

Dr. Cantor: Others have argued that this isn't a campsite

at all, but rather a cache that they left behind on purpose,

intending to return at some point.

Think about it, the site is on elevated ground,

just some 60 odd feet from the shoreline,

so it would have been easily visible

from the sea ice on their return.

Also, there's no proof that the canvas

that was found was actually part of a tent.

It could've been from bags that were used

to bundle all the items together for safekeeping.

Dr. Riskin: And even if they did leave in a hurry,

why would they leave the rock samples behind?

Isn't that what they came for?

And what about the transit in the compass?

Those are valuable instruments,

and they're not that hard to carry.

So there are clearly a lot of unanswered questions.

Narrator: What the discoveries on Axel Heiberg Island represent

and what happened to Hans Kruger and his men is anyone's guess.

Their fate, like that of so many that came before them,

is only known to the endless icy expanse

of the Canadian Arctic.

♪♪

Narrator: Containing the highest peaks

in the Western Hemisphere, the Andes Mountains

are one of Earth's most impressive features,

with an expansive range of towering plateaus and peaks,

the tallest of which reaches an altitude

of over 22,000 feet.

Dr. Cantor: Spanning seven South American countries

and about 5,500 miles,

the Andes are the longest continental

mountain range in the world.

They're not a single continuous line of towering peaks

but a complex arrangement of parallel

and intersecting mountain ranges

as well as plateaus and valleys.

Dr. Leonard: The Pucuncho Basin is over 14,000 feet

above sea level in the Peruvian Andes,

making it one of the highest basins in the range.

With a cold and dry climate, the area can experience

significant temperature fluctuations from day to night,

due to its high altitude.

James Ellis: At this extreme altitude,

vegetation in the basin has adapted to its harsh climate,

while also supporting a variety of high-altitude wildlife

like llamas and alpacas, deer, and Viscachas,

rodent-like mammals,

and several types of birds.

Because of the low oxygen,

life is not booming in the basin,

but it has found a way to survive.

Narrator: While searching for a place to camp for the night,

a team of archeologists researching the mineral obsidian

happen to stumble on something they were not expecting to find.

Dr. Leonard: They notice points and shards that look like

ancient tools made by early tool makers.

And as they continue their search, they find

a natural overhang rock formation that would be ideal

for providing shelter in rough weather conditions.

Dr. Agbedor: The rock shelter opens to the north,

overlooking the eastern side of the Pucuncho Basin.

Inside, they discover rock art,

and notice the ceilings are coated in

thick soot from campfires.

And it's big enough to house about 20 to 30 people.

Dr. Cantor: Next, they find stone tools that are made

of obsidian, andesite and jasper,

all of which can be found in the region.

The tools show traces of plant starch,

probably from domesticated tubers or other plants.

Clearly, this is evidence of an ancient human presence here,

but this area is extremely inhospitable,

with low oxygen and frigid temperatures.

So who were these people and could they have survived

in this environment?

Narrator: Exploring the cave further,

the team makes another surprising discovery.

James Ellis: There is an abundance of animal bones

from creatures like Vicuña and Guanaco Camelids,

which are relatives of llamas and known for their fine wool.

The bones are butchered carefully,

using the stone tools already found.

Dr. Agbedor: The tools found show evidence that they were

not only used for hunting but also for scraping,

and processing hides to make things like clothing.

Which probably means, that people stayed at the settlement

for long periods and were more of a family or tribe,

instead of just hunters going to a hunting area

and bringing back meat.

Narrator: As the research team continues their quest

to find out more, they find something shocking...

James Ellis: Five sets of skeletal remains are found,

two adult women, and three adult men.

Radiocarbon testing dates them to the pre-Inca period,

specifically around 12,000 to 12,400 years ago,

making this the highest ice-age human settlement

ever discovered!

This discovery dates high-altitude human habitation,

nearly a millennium earlier than previously thought.

Dr. Agbedor: Low oxygen, harsh conditions, cold temperatures,

and extreme ultraviolet radiation,

make the Andes Mountains a difficult place to live.

There is also hypoxia, or mountain sickness,

that can cause headaches, vomiting, insomnia,

and just a physical drain on your body.

Dr. Leonard: At high altitudes, the air contains significantly

less oxygen than at sea level, meaning,

each breath provides fewer oxygen molecules.

To adapt to this thinner air, the Andeans have evolved

to be able to carry more oxygen in each red blood cell.

While they breathe at the same rate as people living

at sea level, Andeans can deliver oxygen more efficiently

throughout their bodies.

Dr. Cantor: These genetic adaptations have made it

so that the people living in the Andes

can survive where others can't.

But they wouldn't have had these abilities 12,000 years ago.

Those come with thousands and thousand of years of evolution.

So again we're faced with the question,

how could the people living here survive in these conditions?

Narrator: Looking at other cultures that live

at high altitudes might offer some insight

into how these ancient people were able to adapt

to living in the Pucuncho Basin.

Dr. Leonard: Tibetans are renowned for living

at some of the highest altitudes on Earth.

However, they adapt to low oxygen levels differently

than the Andean people.

Tibetans increase their oxygen intake

by taking more breaths per minute.

Additionally, their lungs produce higher amounts of a gas

called nitric oxide from the air, which widens blood vessels.

So this adaptation helps them compensate for lower

oxygen levels in their blood by increasing blood flow.

James Ellis: In the Ethiopian highlands,

locals have no issues with hypoxia.

However, unlike the Andean people or the Tibetans,

they don't appear to have any evolutionary adaptation,

they're just fine living at high altitudes

and scientists have no clue how they do it.

Narrator: If these early hunter-gatherers

in the Pucuncho Basin had not already evolved

into having these evolutionary traits,

perhaps it was other aspects of living there

that spared them high-altitude sickness.

Dr. Agbedor: There are plenty of things in the natural world

that can also help counterbalance hypoxia.

Some of which are even found

in or close to the Pucuncho Basin.

So it could very well be possible that some of these

practices were used during this time.

Dr. Cantor: Though there isn't much plant life in the region,

one plant that there is an abundance of is the yareta.

The plant is resilient and has adapted to the harsh,

high-altitude environments.

It's bright in color, and typically forms dense,

cushion-like mats or mounds.

James Ellis: In Andean cultures, Yareta has been used

traditionally for its medicinal properties,

used to treat asthma, colds and bronchitis.

It helps for illnesses with inflammation and pain

as the main symptoms.

So maybe these early people were using this plant

to help alleviate any physical problems

due to the environment they were living in.

Narrator: While all of these factors might have helped

with the survival of these people,

the environmental conditions of the time

may have been much different than previously believed.

Dr. Cantor: Finding out that these inhabitants were living

4,000 miles above sea level,

at least a millennium earlier than originally thought,

has led some researchers to revise their opinions

about how extreme the Ice Age actually was,

or at least how long it lasted.

Now it seems that the ice cold temperatures

and frozen landscapes of this ice age,

may have been punctuated by periods

of relatively mild conditions.

James Ellis: For years it was believed

that the Tibetan Plateau was covered by a vast ice shelf

for thousands of years,

leading archaeologists to assume that human habitation

in such an icy environment was impossible,

and thus they did not search for sites from that period.

However, recent findings indicate

that the Tibetan Plateau more closely resembled Arctic tundra,

instead of a complete frozen wasteland.

Dr. Agbedor: Large creatures like mammoths and mastodons

went extinct, and warmer temperatures allowed plants

and animals to move to higher elevations,

creating areas of rich resources like Pucuncho Basin.

Dr. Cantor: This means that the basin might have been a rich,

fertile hunting ground for animals such as

vicunas and guanacos 12,000 years ago.

The slightly cooler and wetter climate would have made it

much more attractive to early humans.

Narrator: As the archeologists continue to search

the surrounding area for more clues

on how these people survived, living at this high altitude,

they discover a second location on the basin's west edge.

James Ellis: It's an open-air workshop that looks like

it was specifically used for working with

the volcanic stone, obsidian.

There are 260 different tools

and even two fishtail arrowheads

made of andesite and obsidian.

Many of the tools are similar to those in the cave,

so the two sites are likely connected.

Dr. Leonard: And just over 90 miles away

is the marine campsite, Quebrada Jaguay,

which was inhabited by early Paleo Indians.

At that site, several stone tools also made of

the same obsidian from the Pucuncho Basin were found.

Dr. Agbedor: This indicates that the people

who crafted these tools, likely traveled

between the coast and the mountains,

where they hunted different animals for meat and pelts,

possibly after the rainy season,

after calves were born in the spring,

or to trade goods with different villages like Quebrada Jaguay.

James Ellis: What's interesting is that no edible plants

grow near the cave, and yet bits of edible roots

and tubers were found.

These must have been sourced from areas at lower elevations,

so again, this would add fuel to the theory,

that this tribe might have been part of a community,

and would make trips to trade goods.

Leonard: With the inhabitants of The Pucuncho Basin

leaving for long periods,

hunting and trading with other groups,

it would have allowed for knowledge to be shared

which is possibly one of the most important parts

of surviving extreme conditions.

Narrator: How the ancient people of the Pucuncho Basin

were able to inhabit the harsh environment

of the Andes mountains, is still not 100% clear,

but they are a fascinating illustration

of the human capacity for adaptability and survival.

♪♪

Narrator: Reaching over 27,000 feet in elevation,

the Himalayan Mountain "Makalu"

is one of the world's highest peaks.

James Ellis: Makalu lies on the Nepalese-Tibetan border,

just 14 miles southeast of Mount Everest.

It's situated in the Makalu Barun National Park,

which covers an area of 900 square miles.

Anthea Nardi: It's known mostly for its' beauty and aesthetics.

Its near-perfect pyramid shape shoots into the sky,

and it's bordered on all sides by stunning views

of the surrounding mountains.

Dr. Leonard: But Makalu is also known for being

one of the most difficult peaks to climb in the world.

It's a huge achievement for anyone who makes it to the top.

First you've got to ascend the steep, glacier-like sides

of the mountain in hostile, sub-zero temperatures.

The peak was only first reached in 1955,

when two French climbers claimed bragging rights.

Narrator: A Mountaineering Team of the Indian Army

is on an expedition near Makalu,

when they come across mysterious marks in the snow.

Dr. Riskin: The markings are impressions measuring

32 inches long, and about 15 inches wide.

Now they're not very deep, they're only a couple of inches.

But they're not just random shapes all over the place.

They really do look like footprints.

James Ellis: The enormous tracks don't look

to be of human origin.

So what creature is responsible for making footprints

above the treeline, in such frigid

and inhospitable conditions?

Is it evidence of the existence

of some as-yet-undiscovered animal?

Narrator: Members of the Indian Expedition team

take photographs of the markings,

and while they can't verify their origin,

the Indian Army tweets the images

out to its nearly six million followers,

adding the caption that they have

"photographic evidence of a Yeti."

James Ellis: The "Yeti," or "Abominable Snowman"

has been part of Himalayan folklore for centuries,

but it has long intrigued people all over the world.

Even Alexander the Great demanded to see

this mysterious creature, when he conquered

the Indus Valley in 326 BC.

He was told that the Yeti only lurked at higher altitudes.

Anthea Nardi: According to the folklore,

the Yeti is supposed to be this massive

part-ape/part-human figure, covered in shaggy fur.

It's been described as the "Bigfoot"

or "Sasquatch" of the mountains.

Dr. Leonard: It's said to be a solitary creature

that roams the snowy Himalayan mountains,

where humans tend not to go.

Not surprisingly, despite several eyewitness sightings

over the years, there's a great deal of mystery

surrounding the Yeti.

Including the very real possibility

that it doesn't exist.

Dr. Riskin: No bodies or bones or fossils have ever been found,

that suggests the existence of an actual Yeti. Ever!

Over all the decades of searching.

And listen, I'm as skeptical as anybody. But here's the thing.

The fact that I'm skeptical, that's irrelevant.

You have to follow the evidence wherever it leads.

And the fact is, there are markings here.

So you have to ask the question.

Could these markings, discovered by the Indian army,

be evidence of a Yeti?

Or if not...what is it?

Narrator: One leading theory behind the Yetis' existence

is that they are surviving relic populations of hominids,

or Neanderthals, an ancient relative of humans.

James Ellis: But the overwhelming scientific evidence

confirms that Neanderthals disappeared

about 30,000 years ago,

even if little pieces of them live on in the form

of DNA sequences scattered through the modern human genome.

Anthea Nardi: Another popular theory maintains

that Yetis are proof that previously "extinct" apes,

like the Gigantopithecus, are not extinct after all.

Evidence of these giant creatures,

closely related to the Orangutan,

shows they lived in the Early Pleistocene period

in Southern China.

Dr. Leonard: The extinction window of Gigantopithecus

is estimated to be between

295,000 to 215,000 years ago,

in correlation with major

environmental changes in the area.

The forest, which provided food for the giant apes,

was replaced by grassland

and the population was thought to have died off.

Is it possible, through evolution,

they adapted to colder climates

and migrated north to the mountains?

Narrator: The modern fascination with the Yeti began in the 1950s

when British explorer Eric Shipton

sighted several abnormal marks,

while he was looking for an alternative route

to climbing Mount Everest.

Dr. Riskin: Shipton and a member of his team saw

what looked like large footprints moving away

from them down a glacier.

Now, fortunately, he had the presence of mind

to take a picture of those prints

next to his pickax for size comparison.

James Ellis: When the photo was published in the press,

it created a frenzy,

particularly in the Western world.

There was something dangerous and slightly romantic about it,

that captured the public's imagination.

And while there was nothing in Shipton's discovery,

that could prove the Yeti's existence,

the figure became very real for many people.

The Nepalese government even issued a hunting licence

in the 1950s, in hopes of capturing the Yeti.

Narrator: A more recent sighting by an explorer

named Graham Hoyland, reveals telling similarities

with the markings at Makalu.

Anthea Nardi: Hoyland was an experienced climber,

who was also trekking in the Himalayas,

He and his team were trying to reach one of the world's

largest unclimbed mountains, Gangkar Punsum,

near the Tibetan border in Bhutan.

And that's where he saw the markings.

Dr. Leonard: Taking advice from a local member of his crew,

Hoyland decided to lead his team through a valley,

that's rarely travelled by Westerners.

He saw a footprint in the snow that,

to his eyes, looked freshly made.

It was much larger than a human foot,

and instead of tell-tale claw marks of a bear,

it appeared the toes of this creature had dug into the snow.

Dr. Riskin: Both discoveries are found in remote areas

of the Himalayas, and they both look like

non-human animals or, in fact,

no known animal.

Narrator: Evidence of strange, unknown creatures

wasn't just limited to Asia.

James Ellis: In the United States,

a US State Forest Service patrolman claimed

he saw a hair-covered creature

that was human in shape and form,

but was over 8 feet tall,

and looked to weigh over 800 pounds.

Which is a fairly accurate description of what's known

as "Bigfoot" or "Sasquatch."

Anthea Nardi: Other Forest Service personnel were called in

to survey the area, and they found evidence of footprints

that were far too large to be from any known primate,

15 inches long and 7 inches across.

However, when they made plaster casts

of three of the found prints,

they revealed that the first digit was "non-opposable, "

a clear indication of being a Hominid,

or some kind of species of 'ape.'

Dr. Leonard: The discovery, along with the Makalu discovery,

certainly raises the possibility

that "Bigfoot" and "Yeti"-like creatures

may roam the world across continents.

Without samples of hard physical evidence,

it's difficult to prove.

However, the US State Department didn't take any chances.

They even created rules on how people were to behave

in its presence, if they happened to run into a Yeti.

Narrator: The 20th century obsession with the Yeti,

Bigfoot, Sasquatch, and other mysterious creatures

gave rise to a phenomenon called "Cryptozoology",

the study and pursuit of unknown lifeforms.

Dr. Leonard: The main goal or mission of Cryptozoologists,

is to prove the existence of these figures.

And the most concrete, rock-solid method to do this,

is with DNA samples and analysis.

Dr. Riskin: In 2012, a team of scientists

at the University of Oxford, led by geneticist Brian Sykes,

sent out this request to get as much material as they could.

They wanted Bigfoot, Sasquatch and Yeti samples

from anywhere they could get them,

any museum, any individual collection

anywhere in the world.

James Ellis: They got a sizeable response,

a total of 57 samples were received,

including hair, fur, teeth, and feces!

The team then subjected the samples to macroscopic,

microscopic and infrared fluorescence,

to eliminate obvious "non-hairs."

Anthea Nardi: The sequences were compared to "GenBank" samples

for species identification,

to see if there was a match with existing animals.

GenBank is essentially an open-source database,

containing all publicly known and available DNA.

Narrator: Despite the wide range in age and condition

of the donated specimens,

Sykes' team yielded sequences

with 100% species identification.

Dr. Leonard: In other words, every sample could be traced

either to an existing lifeform or from pre-existing,

extinct life forms.

One hair sample had a 100% match with DNA recovered

from a Pleistocene fossil of a polar bear jawbone,

but it didn't match the DNA of a modern polar bear.

That suggests it was from a sub-species of bear

that may be a descendent of the ancient polar bear,

which has survived unidentified for millennia,

in the world's highest mountains!

James Ellis: Another hair sample came from an animal,

shot by an experienced hunter in Ladakh, India,

west of the Himalayas, 40 years ago.

The hunter reported that the behaviour of the animal he shot,

was very different from a Brown Bear,

with which he was very familiar.

Narrator: Professor Sykes concluded there was likely

a real, biological animal behind the Yeti myth.

Anthea Nardi: He suspected that the collected hairs

were either from a previously unidentified bear species,

a new colour variant of a polar bear,

or a hybrid of a polar bear and a brown bear.

Although nothing could be proven,

the existence of an undiscovered life-form, similar to a bear,

but not any bear known to us yet,

is incredible to think about.

So, is it possible the "Yeti" footprints discovered

by the Indian army at Makula,

belong to a surviving species of ancient polar bear,

or some kind of hybrid species?

James Ellis: Unfortunately, there's no DNA,

human or otherwise, available to be collected at the Makalu site.

The members of the expedition team

only have the imprinted markings in the snow to go on.

But imagine if they had been able to collect

even one hair sample,

it could unlock the whole mystery.

Narrator: The magic and mythology

of the enigmatic "Yeti" lives on.

And the answer to it's true identity and origin,

is yet to be discovered...

♪♪