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♪ ♪

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♪ ♪

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NARRATOR:
The Arctic Circle,

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Northern Alaska.

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In one of the most
inhospitable places on Earth,

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{\an1}scientists search for clues
to a mystery

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70 million years in the making.

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{\an1}They're on the hunt for
a lost world of polar dinosaurs.

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STEVE BRUSATTE:
This is not the paleontology

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{\an1}you normally see in books.

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{\an7}What we're learning about
dinosaurs

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{\an7}from these discoveries,

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it's just really
unparalleled and unprecedented.

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♪ ♪

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NARRATOR:
Alaska is the last place
on Earth

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one might expect
to find large reptiles.

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{\an1}But the discovery of fossils has
revealed dinosaurs could live

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{\an1}farther north than what
was once thought possible.

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{\an1}(power tools running)

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{\an1}Oh, we got a sweet layer
right here.

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(tools running)

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NARRATOR:
Now this team hopes to

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answer some
fundamental questions.

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{\an1}What kind of animals lived here?

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How did they survive
the Arctic winters?

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BRUSATTE:
How were they able to
endure the cold?

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How were they able
to endure the darkness?

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Where do they get their food?

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GREGORY ERICKSON:
If they were up here year-round,

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were they really
warm-blooded animals?

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NARRATOR:
Their journey will take them

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{\an1}from the frozen wilderness
of Northern Alaska

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to the mountaintops

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of Denali
National Park and Preserve

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to the south.

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RILEY BLACK:
If we can understand

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{\an1}how they survived here,

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{\an1}we might be able to understand

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{\an1}why they dominated the planet
for over 100 million years.

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♪ ♪

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NARRATOR:
A surprising story...

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(barks)

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{\an1}...of adaptation and survival...

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(birds chirping)

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against the odds.

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NARRATOR:
"Alaskan Dinosaurs."

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{\an1}Right now, on "NOVA."

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♪ ♪

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ANNOUNCER:
Major funding for "NOVA"
is provided by the following:

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(wind whipping)

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NARRATOR:
Late March,

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{\an1}Alaska's North Slope.

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28 miles
south of the Arctic Ocean,

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{\an1}a team of paleontologists

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{\an1}is on the final leg of
a 600-mile journey

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from Fairbanks to
one of the northernmost reaches

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of North America.

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{\an1}They're part of a long-term

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{\an1}joint research project
studying polar dinosaurs.

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Their plan is to

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{\an1}spend the next several days
searching for dino bones.

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PAT DRUCKENMILLER:
What makes these dinosaurs
amazing is the fact that

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they lived in an
extreme environment.

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{\an7}This isn't the sort of thing

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{\an7}we typically associate
with dinosaurs.

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{\an7}So the fact that they lived
at these latitudes

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{\an1}tells us a lot about what
dinosaurs were capable of doing.

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{\an1}It shows them at their extremes.

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NARRATOR:
Over the past 13 years,

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paleontologist
Pat Druckenmiller has made

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11 expeditions
to the North Slope

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{\an1}in search of fossils.

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{\an1}He's joined by paleobiologist
Gregory Erickson,

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also a veteran
of this field work.

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ERICKSON:
Alaska is really
paleontology's last frontier.

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{\an7}Dinosaurs were living in the
coldest environment

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{\an8}in the Cretaceous,
and it's a mystery as to,

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{\an7}you know, how they were making
it up there.

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{\an1}How did they survive?

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♪ ♪

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NARRATOR:
Here, temperatures drop to
50 below at night,

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{\an1}with wind chills plunging
even lower.

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{\an1}But despite these challenges,

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{\an1}this is the ideal time
to go fossil hunting

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on the North Slope.

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DRUCKENMILLER:
The hillside we're trying to
dig out

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likes to slump on us
in the summer.

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{\an1}But in the wintertime,
it's frozen solid

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{\an1}and we can safely excavate
into the layer.

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{\an1}(strap pulls tightly)

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NARRATOR:
Along with excavation equipment,

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{\an1}they'll be carrying everything
they need to survive,

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{\an1}including 100 gallons of
gasoline to run generators,

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one ton of wood for fire stoves,

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{\an1}and enough food to last for
over a week.

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DRUCKENMILLER:
It's been three days of travel
just to reach this point,

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{\an1}and we're not over yet,
because we now have to travel

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{\an1}about 30 miles by snow machine
to get out to the Colville River

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{\an1}and reach our actual dig site.

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(engine starts)

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♪ ♪

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NARRATOR:
The team is heading to
a fossil site

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{\an1}in the Prince Creek Formation

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{\an1}on the North Slope of Alaska.

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Through this remote,
awe-inspiring landscape

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{\an1}winds the Colville River,
flowing north from

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{\an1}the slopes of the Brooks Range
to the Beaufort Sea.

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{\an8}Along the bank
of the frozen river,

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{\an7}steep cliffs rise 100 feet.

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{\an8}This is where
geologist Robert Liscomb

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{\an7}came across mysterious bones

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{\an8}while working for an oil company

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{\an8}in 1961.

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{\an8}Later identified as
dinosaur bones,

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{\an7}the find was a surprise.

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{\an8}Dinos,
thought to be cold-blooded,

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{\an7}shouldn't be able to survive
in the cold and dark.

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{\an7}Polar dinosaurs weren't really
on paleontologists' radar

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{\an8}for most of the 20th century.

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{\an7}When you had a picture of

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what a dinosaur was
and where they lived,

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{\an1}it was often thought to be
an equatorial sort of creature,

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{\an1}a creature of warm environments,

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{\an1}of these swampy sort of
lowland environments.

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{\an1}Thinking of dinosaurs living
in the polar north,

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{\an1}that wasn't something that was
even considered.

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♪ ♪

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NARRATOR:
The discovery of
Alaskan dinosaurs

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astonishes
the scientific community...

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and puts the
Prince Creek Formation

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on the map for paleontologists.

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♪ ♪

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BLACK:
To find them in
a place like this,

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{\an1}where the environment is
so dramatically different,

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{\an1}it really does challenge what
we thought about these animals.

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NARRATOR:
So far, scientists have
identified

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{\an1}over a dozen species,
both large and small:

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herbivorous beasts
such as Pachyrhinosaurus,

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{\an1}a formidable horned ceratopsid;

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{\an1}and Ugrunaaluk, a duck-billed
dinosaur over 25 feet long;

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as well as predators
like Nanuqsaurus,

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{\an1}a fearsome tyrannosaur and
close cousin to T. rex;

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and a troodontid,
a lightly built horse-sized

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dinosaur with
deadly slasher claws.

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{\an1}The team finally arrives

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at base camp,
half a mile from the dig site.

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{\an1}It's getting dark and
the temperature is dropping,

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now down to
minus-four degrees Fahrenheit.

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The site that we're
interested in

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is at that point over there.

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{\an1}But some of our crew is
getting cold,

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{\an1}and so it's important
to get our tents up and,

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you know, get our stoves going.

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NARRATOR:
Working on the North Slope
in the late winter

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means the days are
still short and cold.

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Scientists agree,
70 million years ago,

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the Earth was
generally much warmer.

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The dinosaurs
living here, however,

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would have faced
the same inescapable reality.

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{\an7}As the Earth orbits the sun,
it rotates on a tilted axis.

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{\an8}During summer in
the Northern Hemisphere,

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{\an8}the North Pole is
angled toward the sun.

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{\an7}Areas above the Arctic Circle

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{\an8}receive 24 hours of sunlight.

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{\an7}But when Earth arrives at
the opposite side of its orbit,

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{\an7}the pattern reverses,
and the north is tilted

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{\an8}away from the sun.

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{\an7}Because during the Cretaceous,

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{\an7}Alaska was even farther north
than today,

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{\an7}the North Slope experienced
four months of total darkness.

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BRUSATTE:
The best indications

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{\an1}from all of the geological
and fossil evidence

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{\an7}is that during that darkest,
coldest winter months,

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{\an8}it would have gotten
below freezing.

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It would have been much colder

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{\an1}than almost anywhere else

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dinosaurs
would have been living.

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♪ ♪

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NARRATOR:
Early the next morning,

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{\an1}Pat and Greg visit the site

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{\an1}where the first Alaskan
dinosaurs were discovered:

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{\an1}the Liscomb Bone Bed.

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(snow crunching)

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DRUCKENMILLER:
We have somewhere around

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{\an1}6,000 catalogued bones
in our collection

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{\an1}from this one layer alone.

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{\an1}And it's also the same layer

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{\an1}that provided most of the
material

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from which we named
a new species

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{\an1}of duck-billed dinosaur

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{\an1}called Ugrunaaluk kuukpikensis.

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{\an1}The areas that we work in

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{\an1}have been long occupied
by Indigenous peoples,

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{\an1}and we think it's only fitting

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{\an1}that when we construct
a new scientific name,

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that we incorporate
words from those languages

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from the areas in which we work.

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{\an1}Ugrunaaluk kuukpikensis
has its origin

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in Inupiaq words
that mean, roughly,

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"ancient chewer
of the Colville River."

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NARRATOR:
Close cousin to Edmontosaurus
found to the south,

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{\an1}Ugrunaaluk kuukpikensis

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{\an1}is a four-ton herbivore.

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Its discovery
in Alaska's North Slope

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created a puzzle for scientists.

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{\an1}How did these large animals
manage to survive so far north?

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(dinosaur lowing)

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{\an1}Did they migrate to and from
lower latitudes each year...

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{\an1}...like caribou do today?

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ERICKSON:
If they weren't migrating,

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{\an1}how did they make a living
up here?

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You can't imagine
there was enough to eat,

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{\an1}so it's just, you know,
a bit of a mystery.

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♪ ♪

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NARRATOR:
To find clues,

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the scientists hope
to recover more bone material.

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00:12:01,633 --> 00:12:03,442
(dog barking)

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{\an1}During the Cretaceous, some 145
to 66 million years ago,

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{\an1}the section they're planning to
dig was a river floodplain.

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(birds chirping)

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{\an8}Over millennia,
some remains of dinosaurs

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{\an7}find their way into rivers.

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{\an7}Bones and other material
from different species

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{\an7}pile up at the bottom of
the river channel.

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{\an7}Layers of sediment bury
the remains.

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{\an7}Millions of years later,
a new river, the Colville,

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{\an7}carves through these layers,

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{\an8}exposing the edge of
the fossil bone bed

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{\an8}along these cliffs.

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00:12:44,433 --> 00:12:46,842
(murmuring)

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NARRATOR:
Pat examines the spot
where they found bones before.

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They've come back
to continue the work,

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but the familiar
landscape has changed.

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Huh.

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00:13:04,800 --> 00:13:06,976
{\an1}That's kind of scary.

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{\an1}It might have gone bye-bye.

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NARRATOR:
On first inspection,
things don't look promising.

238
00:13:15,800 --> 00:13:17,809
DRUCKENMILLER:
It's all slump.

239
00:13:17,833 --> 00:13:19,109
ERICKSON:
Yeah.

240
00:13:19,133 --> 00:13:20,373
DRUCKENMILLER:
The layer's gone.

241
00:13:24,733 --> 00:13:27,876
NARRATOR:
In the summer,
the faces of these cliffs

242
00:13:27,900 --> 00:13:31,776
regularly slump or
slide down into the river,

243
00:13:31,800 --> 00:13:34,900
making it dangerous
to work here.

244
00:13:36,566 --> 00:13:40,133
{\an1}That process can expose fossils
that had been hidden.

245
00:13:41,566 --> 00:13:43,976
But it can also bury
the bone layer...

246
00:13:44,000 --> 00:13:48,866
{\an1}and paleontologists...
Under tons of rock and mud.

247
00:13:50,500 --> 00:13:54,276
{\an1}The team fears its bone bed
may have been washed away.

248
00:13:54,300 --> 00:13:56,509
DRUCKENMILLER:
The hills are ungluing
themselves.

249
00:13:56,533 --> 00:13:57,742
Rack it up to

250
00:13:57,766 --> 00:14:00,809
{\an1}climate change or whatever,
but you never know.

251
00:14:00,833 --> 00:14:02,642
{\an1}The slumps can randomly just

252
00:14:02,666 --> 00:14:05,476
take out your
favorite dinosaur site.

253
00:14:05,500 --> 00:14:08,200
{\an1}Yeah, that's not good.

254
00:14:09,166 --> 00:14:12,409
NARRATOR:
Then, after further exploration,

255
00:14:12,433 --> 00:14:16,009
they find
a newly exposed outcrop.

256
00:14:16,033 --> 00:14:20,076
{\an1}Oh, it's kinda got some slump
on it.

257
00:14:20,100 --> 00:14:21,766
{\an1}All right, I'm going up
and have a look.

258
00:14:24,100 --> 00:14:25,276
NARRATOR:
Just when it looks like

259
00:14:25,300 --> 00:14:27,509
{\an1}the trip may have been
for nothing,

260
00:14:27,533 --> 00:14:31,342
{\an1}the team has a stroke of luck.

261
00:14:31,366 --> 00:14:32,842
Look at that.

262
00:14:32,866 --> 00:14:35,642
Right there.

263
00:14:35,666 --> 00:14:37,909
Woo-hoo!

264
00:14:37,933 --> 00:14:38,942
{\an1}Found the first bone!

265
00:14:38,966 --> 00:14:40,009
(man responds)

266
00:14:40,033 --> 00:14:42,609
{\an1}(sniffs)

267
00:14:42,633 --> 00:14:44,676
DRUCKENMILLER:
Oh, we got a sweet layer
right here.

268
00:14:44,700 --> 00:14:45,876
That's good.

269
00:14:45,900 --> 00:14:49,242
NARRATOR:
Pieces of bone are
clearly visible,

270
00:14:49,266 --> 00:14:52,909
sticking out of the frozen rock.

271
00:14:52,933 --> 00:14:55,176
{\an8}DRUCKENMILLER:
I whacked right through
one here.

272
00:14:55,200 --> 00:14:58,276
{\an7}It's classic bone texture.

273
00:14:58,300 --> 00:15:01,442
{\an8}NARRATOR:
For Pat, this layer is

274
00:15:01,466 --> 00:15:04,476
a paleontological gold mine.

275
00:15:04,500 --> 00:15:05,709
That's what this
bone layer is all about.

276
00:15:05,733 --> 00:15:06,776
{\an1}It's just dripping with bones.

277
00:15:06,800 --> 00:15:09,709
(tool scraping)

278
00:15:09,733 --> 00:15:10,842
(blows)

279
00:15:10,866 --> 00:15:12,042
NARRATOR:
The challenge now

280
00:15:12,066 --> 00:15:15,442
is to safely extract
the samples.

281
00:15:15,466 --> 00:15:19,309
ERICKSON:
No one's ever tried this
up here before.

282
00:15:19,333 --> 00:15:20,742
{\an1}Digging these animals up here,

283
00:15:20,766 --> 00:15:22,609
you know, basically
the end of wintertime,

284
00:15:22,633 --> 00:15:23,876
we're gonna take
the whole layer,

285
00:15:23,900 --> 00:15:25,609
rock and the bones,

286
00:15:25,633 --> 00:15:27,042
{\an1}and try to extract it.

287
00:15:27,066 --> 00:15:28,142
{\an1}Gotta find the sweet spot.

288
00:15:28,166 --> 00:15:29,209
{\an6}MAN:
Yep.
There it is.

289
00:15:29,233 --> 00:15:32,366
{\an1}(jackhammer grinding)

290
00:15:34,900 --> 00:15:37,076
NARRATOR:
They have just six days left
to collect specimens

291
00:15:37,100 --> 00:15:40,266
{\an1}before they need to return.

292
00:15:41,500 --> 00:15:44,676
{\an1}The next steps are to break up
the frozen mud and rock

293
00:15:44,700 --> 00:15:47,342
below the bone layer
with jackhammers

294
00:15:47,366 --> 00:15:50,442
{\an1}to create a working platform.

295
00:15:50,466 --> 00:15:52,742
{\an1}Then carve out several blocks
with chainsaws.

296
00:15:52,766 --> 00:15:57,842
Each chunk will be
about three feet across

297
00:15:57,866 --> 00:16:00,600
{\an1}and weigh up to 200 pounds.

298
00:16:06,133 --> 00:16:09,442
It's five days into
a ten-day expedition.

299
00:16:09,466 --> 00:16:11,609
{\an1}They still haven't extracted
a single block.

300
00:16:11,633 --> 00:16:15,533
And then they suffer
another setback.

301
00:16:17,533 --> 00:16:20,976
{\an1}The chainsaws break down.

302
00:16:21,000 --> 00:16:25,909
{\an1}It's up to head of operations
Kevin May to fix the equipment.

303
00:16:25,933 --> 00:16:28,142
MAY:
It is.

304
00:16:28,166 --> 00:16:30,676
{\an1}We have been presented with

305
00:16:30,700 --> 00:16:32,776
{\an1}some significant challenges here

306
00:16:32,800 --> 00:16:35,076
{\an1}with the temperatures.
(man coughing)

307
00:16:35,100 --> 00:16:39,642
NARRATOR:
If he can't get the chainsaws
back up and running,

308
00:16:39,666 --> 00:16:41,742
{\an1}the expedition could be over.

309
00:16:41,766 --> 00:16:43,009
Where's the other...

310
00:16:43,033 --> 00:16:45,042
{\an1}Pal, you're too soon.

311
00:16:45,066 --> 00:16:47,909
{\an1}DRUCKENMILLER:
How long do you need?

312
00:16:47,933 --> 00:16:49,409
MAY:
I was really hoping
to get over here

313
00:16:49,433 --> 00:16:52,400
{\an1}and work on the chainsaws
by myself, so...

314
00:16:54,833 --> 00:16:58,209
{\an7}You get too many PhDs
in a small area

315
00:16:58,233 --> 00:17:00,333
{\an7}and nothing gets done.

316
00:17:02,666 --> 00:17:06,609
NARRATOR:
Kevin soon discovers
a possible solution.

317
00:17:06,633 --> 00:17:09,309
Yep, that's what
shut us down last night.

318
00:17:09,333 --> 00:17:10,809
Look at that.

319
00:17:10,833 --> 00:17:14,233
{\an1}Can you thaw that, please?

320
00:17:16,800 --> 00:17:20,309
NARRATOR:
The friction from the chainsaws
melts the permafrost,

321
00:17:20,333 --> 00:17:24,966
{\an1}which seeps into the mechanics
and immediately refreezes.

322
00:17:27,366 --> 00:17:28,409
MAY:
Turns out that

323
00:17:28,433 --> 00:17:30,442
{\an1}because of these temperatures,

324
00:17:30,466 --> 00:17:34,109
we're gonna have to
repeatedly warm our chainsaws

325
00:17:34,133 --> 00:17:37,900
and get the chains
thawed out a bit.

326
00:17:43,700 --> 00:17:45,042
NARRATOR:
After a thorough cleaning,

327
00:17:45,066 --> 00:17:48,476
{\an1}the team tries again.

328
00:17:48,500 --> 00:17:52,176
(tool whirring)

329
00:17:52,200 --> 00:17:53,976
Four more days
in the biting cold

330
00:17:54,000 --> 00:17:56,142
digging,

331
00:17:56,166 --> 00:17:58,109
sawing,

332
00:17:58,133 --> 00:17:59,942
sleeping,

333
00:17:59,966 --> 00:18:02,709
and more sawing

334
00:18:02,733 --> 00:18:06,509
{\an1}before the first block
is finally freed.

335
00:18:06,533 --> 00:18:09,600
{\an1}DRUCKENMILLER:
It's coming, it's coming.

336
00:18:15,600 --> 00:18:18,042
ERICKSON:
Well done, Pat.

337
00:18:18,066 --> 00:18:19,309
We have success!

338
00:18:19,333 --> 00:18:22,476
{\an1}Yeah, that's
a really nice, big chunk.

339
00:18:22,500 --> 00:18:24,409
There's a big one right there.

340
00:18:24,433 --> 00:18:27,776
{\an7}DRUCKENMILLER:
Big, very dark,
there's one right here.

341
00:18:27,800 --> 00:18:31,809
{\an7}There's one there,
there's one there.

342
00:18:31,833 --> 00:18:35,542
{\an1}It's full of bones.

343
00:18:35,566 --> 00:18:38,542
{\an1}DRUCKENMILLER (sighing):
After all that time...

344
00:18:38,566 --> 00:18:41,309
(laughs):
We've got it.

345
00:18:41,333 --> 00:18:44,242
ERICKSON:
We're hitting the jackpot
right now.

346
00:18:44,266 --> 00:18:45,809
{\an1}This is gonna pay off.
(laughs)

347
00:18:45,833 --> 00:18:47,366
Let's bring it in for a landing.

348
00:18:48,633 --> 00:18:50,042
NARRATOR:
In total,

349
00:18:50,066 --> 00:18:54,709
{\an1}the paleontologists manage
to extract eight frozen blocks,

350
00:18:54,733 --> 00:18:57,242
{\an1}1,000 pounds to haul home.

351
00:18:57,266 --> 00:18:58,409
DRUCKENMILLER:
And now it's just a matter of

352
00:18:58,433 --> 00:19:00,676
{\an1}bringing home a bunch of rock,

353
00:19:00,700 --> 00:19:02,676
{\an1}and we'll get that stuff
back in the lab,

354
00:19:02,700 --> 00:19:06,176
{\an1}and we can prepare it out
and we'll see what we find.

355
00:19:06,200 --> 00:19:08,609
♪ ♪

356
00:19:08,633 --> 00:19:11,009
NARRATOR:
They hope the samples will

357
00:19:11,033 --> 00:19:13,776
{\an1}contain fossils that can
fill out their understanding

358
00:19:13,800 --> 00:19:19,009
{\an1}of the animals that lived here
and help answer the question

359
00:19:19,033 --> 00:19:23,376
at the heart of
the Alaskan dinosaur mystery:

360
00:19:23,400 --> 00:19:26,542
how did they survive
the dark polar winter?

361
00:19:26,566 --> 00:19:29,642
BRUSATTE:
That's a tough place
to make a living.

362
00:19:29,666 --> 00:19:31,309
How were dinosaurs
able to do that?

363
00:19:31,333 --> 00:19:34,409
{\an1}Did they have to leave,

364
00:19:34,433 --> 00:19:36,842
maybe migrate south?

365
00:19:36,866 --> 00:19:39,342
{\an8}Or were they able to
park themselves

366
00:19:39,366 --> 00:19:40,809
{\an7}in the poles year-round?

367
00:19:40,833 --> 00:19:43,776
{\an8}BLACK:
If we have evidence that they
were staying year-round,

368
00:19:43,800 --> 00:19:47,309
{\an7}it really has a powerful impact

369
00:19:47,333 --> 00:19:51,476
on what we expect of
dinosaur physiology.

370
00:19:51,500 --> 00:19:54,909
♪ ♪

371
00:19:54,933 --> 00:19:58,042
NARRATOR:
Early July.

372
00:19:58,066 --> 00:19:59,942
{\an1}At the University of Alaska

373
00:19:59,966 --> 00:20:02,009
{\an1}Museum of the North in
Fairbanks,

374
00:20:02,033 --> 00:20:04,942
the blocks from
the Prince Creek Formation

375
00:20:04,966 --> 00:20:06,776
are in the prep lab.

376
00:20:06,800 --> 00:20:08,776
♪ ♪

377
00:20:08,800 --> 00:20:10,976
{\an1}It's not just the big bones

378
00:20:11,000 --> 00:20:12,900
{\an1}the scientists are after.

379
00:20:16,266 --> 00:20:19,476
Even the tiniest
unassuming crumbs

380
00:20:19,500 --> 00:20:23,242
{\an1}could hold vital pieces
of the Alaskan dinosaur puzzle.

381
00:20:23,266 --> 00:20:26,333
♪ ♪

382
00:20:28,033 --> 00:20:32,942
{\an1}To ensure the tiniest fragment
isn't overlooked,

383
00:20:32,966 --> 00:20:36,942
{\an1}the scientists scrutinize
buckets of material

384
00:20:36,966 --> 00:20:38,800
grain by grain.

385
00:20:40,233 --> 00:20:42,276
DRUCKENMILLER:
It's a process of

386
00:20:42,300 --> 00:20:44,209
{\an7}finding a needle in a haystack,
or...

387
00:20:44,233 --> 00:20:46,276
{\an8}I liken it more
to panning for gold.

388
00:20:46,300 --> 00:20:52,209
♪ ♪

389
00:20:52,233 --> 00:20:53,676
NARRATOR:
Three years earlier,

390
00:20:53,700 --> 00:20:58,009
{\an1}on their previous expedition
to the Prince Creek Formation,

391
00:20:58,033 --> 00:21:01,842
Pat and Greg find
something exceedingly rare

392
00:21:01,866 --> 00:21:04,676
{\an1}and a potential clue to
the mystery of the lifestyle

393
00:21:04,700 --> 00:21:08,676
of polar dinosaurs:

394
00:21:08,700 --> 00:21:14,642
{\an1}very small bones they suspect
are from a very young dinosaur.

395
00:21:14,666 --> 00:21:18,100
{\an1}Some are no larger than
the head of a pin.

396
00:21:20,900 --> 00:21:24,642
{\an1}Small size alone doesn't
necessarily mean that

397
00:21:24,666 --> 00:21:28,042
{\an1}this is from a very young
individual dinosaur.

398
00:21:28,066 --> 00:21:30,942
{\an1}For that information,
I look at other clues.

399
00:21:30,966 --> 00:21:32,509
{\an1}And one of the best clues

400
00:21:32,533 --> 00:21:35,276
can be seen
in the surface texture.

401
00:21:35,300 --> 00:21:37,576
♪ ♪

402
00:21:37,600 --> 00:21:40,276
{\an1}What I'm seeing is a surface
that's highly porous,

403
00:21:40,300 --> 00:21:42,842
{\an1}as if somebody took a little pin
and pricked the surface

404
00:21:42,866 --> 00:21:44,533
over and over and over again.

405
00:21:46,633 --> 00:21:49,376
{\an1}And each of those holes
represents places

406
00:21:49,400 --> 00:21:51,409
{\an1}for little vascular canals

407
00:21:51,433 --> 00:21:54,142
where nutrients
were flowing into a bone

408
00:21:54,166 --> 00:21:56,842
{\an1}at a stage of rapid growth.

409
00:21:56,866 --> 00:22:01,009
{\an1}That sort of surface texture is
highly indicative of

410
00:22:01,033 --> 00:22:04,042
{\an1}animals' very early stages
of development.

411
00:22:04,066 --> 00:22:05,842
And by that we mean days, weeks,

412
00:22:05,866 --> 00:22:07,409
maybe as much as
a couple of months,

413
00:22:07,433 --> 00:22:09,776
meaning that
this is a great clue

414
00:22:09,800 --> 00:22:12,076
{\an1}to help identify baby bones.

415
00:22:12,100 --> 00:22:18,100
♪ ♪

416
00:22:19,733 --> 00:22:23,342
NARRATOR:
It's an unprecedented find.

417
00:22:23,366 --> 00:22:27,633
{\an1}Baby dinosaurs have never been
found this far north before.

418
00:22:30,333 --> 00:22:33,209
DRUCKENMILLER:
This was a totally unexpected
discovery.

419
00:22:33,233 --> 00:22:34,809
{\an1}When we first started to see

420
00:22:34,833 --> 00:22:37,309
{\an1}these, these small teeth and
bones,

421
00:22:37,333 --> 00:22:42,576
{\an1}it was, it was really a
jaw-dropping experience.

422
00:22:42,600 --> 00:22:44,742
NARRATOR:
Further investigation reveals

423
00:22:44,766 --> 00:22:46,742
{\an1}remains of the teeth and bones

424
00:22:46,766 --> 00:22:50,576
{\an1}of seven different species
of dinosaur,

425
00:22:50,600 --> 00:22:54,376
all in their very
earliest stages of development.

426
00:22:54,400 --> 00:22:59,142
It's evidence
that 70 million years ago,

427
00:22:59,166 --> 00:23:04,742
{\an1}several species of dinosaurs
nested in the Arctic,

428
00:23:04,766 --> 00:23:07,876
{\an1}not only living in Alaska
during the mild summer,

429
00:23:07,900 --> 00:23:10,133
{\an1}but breeding here, as well.

430
00:23:13,900 --> 00:23:17,500
DRUCKENMILLER:
It raises a whole bunch of
really interesting questions.

431
00:23:18,666 --> 00:23:20,209
{\an1}One of the most important is,

432
00:23:20,233 --> 00:23:22,542
if they reproduced
in the Arctic,

433
00:23:22,566 --> 00:23:25,409
{\an1}is it actually possible for them
to have also had time

434
00:23:25,433 --> 00:23:28,542
{\an1}to migrate to lower latitudes?

435
00:23:28,566 --> 00:23:33,376
NARRATOR:
If migratory, dinosaurs
would have to move north,

436
00:23:33,400 --> 00:23:36,076
{\an1}incubate and hatch their eggs,

437
00:23:36,100 --> 00:23:38,376
{\an1}and then return to the south,

438
00:23:38,400 --> 00:23:43,209
{\an8}2,000 miles away,
with baby dinosaurs in tow,

439
00:23:43,233 --> 00:23:47,376
{\an7}in order to escape the depth of
the polar winter shadow...

440
00:23:47,400 --> 00:23:50,942
{\an8}and all between
spring and early fall.

441
00:23:50,966 --> 00:23:53,476
{\an8}Could the hatchlings
have managed it?

442
00:23:53,500 --> 00:23:56,809
♪ ♪

443
00:23:56,833 --> 00:24:01,409
{\an1}One important clue can be found
inside specimens like this,

444
00:24:01,433 --> 00:24:05,676
less than
an eighth of an inch long.

445
00:24:05,700 --> 00:24:07,709
{\an1}It looks like a drill bit,

446
00:24:07,733 --> 00:24:11,833
but it's actually
a tooth from a baby dinosaur.

447
00:24:14,033 --> 00:24:18,942
{\an1}When teeth form, daily growth
lines are laid down.

448
00:24:18,966 --> 00:24:20,742
{\an1}And by counting those up,
one can figure out

449
00:24:20,766 --> 00:24:23,876
{\an1}how long it took dinosaurs
to incubate their eggs.

450
00:24:23,900 --> 00:24:25,876
{\an8}So we looked
at really small embryos,

451
00:24:25,900 --> 00:24:28,342
{\an8}animals that were
just about to hatch out,

452
00:24:28,366 --> 00:24:31,609
{\an1}and we were able to figure out
really large dinosaur eggs

453
00:24:31,633 --> 00:24:33,976
{\an1}took six months to incubate.

454
00:24:34,000 --> 00:24:37,442
♪ ♪

455
00:24:37,466 --> 00:24:41,942
NARRATOR:
If it took large animals
such as Ugrunaaluk

456
00:24:41,966 --> 00:24:43,509
six months to hatch,

457
00:24:43,533 --> 00:24:46,209
and eggs were laid
during the spring,

458
00:24:46,233 --> 00:24:49,876
{\an1}the dinosaurs would have
only one month to move south

459
00:24:49,900 --> 00:24:55,109
{\an1}before the onset of polar
winter.

460
00:24:55,133 --> 00:24:56,842
There's no way that
those dinosaurs

461
00:24:56,866 --> 00:25:00,009
{\an1}could have hatched out
and made a 2,000-mile trek

462
00:25:00,033 --> 00:25:04,042
{\an1}all the way down to Alberta
to warmer climatic conditions.

463
00:25:04,066 --> 00:25:06,009
{\an1}It just wasn't possible.

464
00:25:06,033 --> 00:25:08,342
{\an1}It's just unavoidable...
They were up there year-round.

465
00:25:08,366 --> 00:25:10,476
♪ ♪

466
00:25:10,500 --> 00:25:13,409
NARRATOR:
The idea that dinosaurs
lived in cold darkness

467
00:25:13,433 --> 00:25:17,976
{\an1}challenges previous assumptions
about dinosaur biology

468
00:25:18,000 --> 00:25:19,976
{\an1}and the traditional view
that they were

469
00:25:20,000 --> 00:25:24,476
{\an1}giant cold-blooded animals
like today's reptiles,

470
00:25:24,500 --> 00:25:28,942
{\an1}relying on ambient temperature
to warm their bodies.

471
00:25:28,966 --> 00:25:31,842
{\an1}What we don't find in
the Prince Creek Formation

472
00:25:31,866 --> 00:25:34,742
is evidence for
cold-blooded animals

473
00:25:34,766 --> 00:25:40,142
{\an1}such as crocodiles and turtles,
lizards, amphibians.

474
00:25:40,166 --> 00:25:44,242
{\an7}It's almost like they
were physiologically limited.

475
00:25:44,266 --> 00:25:46,342
{\an7}What we do find up there
are birds

476
00:25:46,366 --> 00:25:49,076
and mammals

477
00:25:49,100 --> 00:25:51,509
and dinosaurs.

478
00:25:51,533 --> 00:25:54,209
That alone suggested
that they were warm-blooded.

479
00:25:54,233 --> 00:25:58,109
♪ ♪

480
00:25:58,133 --> 00:26:00,242
NARRATOR:
Even if they weren't
cold-blooded,

481
00:26:00,266 --> 00:26:05,333
{\an1}how did herbivores like
Ugrunaaluk find enough food?

482
00:26:08,400 --> 00:26:11,676
Without sunlight,
many trees shed their leaves.

483
00:26:11,700 --> 00:26:17,076
{\an1}During these winter months,
food for the plant-eaters

484
00:26:17,100 --> 00:26:19,266
{\an1}would have withered or died.

485
00:26:23,400 --> 00:26:26,676
♪ ♪

486
00:26:26,700 --> 00:26:29,476
KAREN CHIN:
If we think about those
Alaskan ecosystems,

487
00:26:29,500 --> 00:26:33,242
{\an7}we have to address the fact...

488
00:26:33,266 --> 00:26:34,210
{\an8}(mouths)

489
00:26:34,234 --> 00:26:35,800
{\an7}Where do they get their food?

490
00:26:37,233 --> 00:26:40,409
NARRATOR:
Karen Chin is one of the world's
leading experts

491
00:26:40,433 --> 00:26:43,842
in dinosaur dung.

492
00:26:43,866 --> 00:26:47,176
{\an1}She's been investigating
hadrosaur diet

493
00:26:47,200 --> 00:26:49,709
{\an1}by studying the fossilized
remains of their feces,

494
00:26:49,733 --> 00:26:53,342
known as coprolites.

495
00:26:53,366 --> 00:26:57,409
♪ ♪

496
00:26:57,433 --> 00:26:59,742
{\an1}At 100 times magnification,

497
00:26:59,766 --> 00:27:02,776
even the individual
fossilized cells

498
00:27:02,800 --> 00:27:06,033
{\an1}of the dinosaur's last meal
are visible.

499
00:27:09,100 --> 00:27:12,442
{\an1}Investigating coprolites
from non-polar dinosaurs

500
00:27:12,466 --> 00:27:14,676
living in
Southern Utah and Montana,

501
00:27:14,700 --> 00:27:17,209
{\an1}Karen finds something
intriguing.

502
00:27:17,233 --> 00:27:20,409
{\an1}We can see chunks of intact
wood,

503
00:27:20,433 --> 00:27:23,342
{\an1}and that's where you see
all of the cells

504
00:27:23,366 --> 00:27:25,609
{\an1}are almost glued together.

505
00:27:25,633 --> 00:27:27,742
{\an1}They're glued together
with lignin.

506
00:27:27,766 --> 00:27:32,276
{\an1}But then you can also see
all of these loose cells

507
00:27:32,300 --> 00:27:35,742
all over the place,
in no particular order,

508
00:27:35,766 --> 00:27:39,342
{\an1}scattered all around.

509
00:27:39,366 --> 00:27:43,342
♪ ♪

510
00:27:43,366 --> 00:27:47,076
{\an1}And that indicates rotting wood.

511
00:27:47,100 --> 00:27:51,776
{\an1}To break down lignin,
it requires oxygen,

512
00:27:51,800 --> 00:27:54,976
so that can't happen
in an animal's gut.

513
00:27:55,000 --> 00:27:59,276
{\an1}It has to happen outside,
where there's access to oxygen.

514
00:27:59,300 --> 00:28:03,776
{\an1}So we know that the wood
was degraded, decomposed,

515
00:28:03,800 --> 00:28:07,000
{\an1}before it was ingested
by the dinosaur.

516
00:28:08,966 --> 00:28:10,109
{\an1}I was quite surprised...

517
00:28:10,133 --> 00:28:13,809
Why were they eating
so much wood?

518
00:28:13,833 --> 00:28:16,176
NARRATOR:
The incredible new evidence

519
00:28:16,200 --> 00:28:20,076
{\an1}suggests the southern hadrosaurs
could diversify their diets,

520
00:28:20,100 --> 00:28:24,942
{\an1}feeding on rotting wood
to survive.

521
00:28:24,966 --> 00:28:27,809
{\an1}Where are you going to get
protein if you're an herbivore?

522
00:28:27,833 --> 00:28:30,009
{\an1}You can go to a rotting log

523
00:28:30,033 --> 00:28:33,376
{\an1}where there's lots of
creepy crawlers

524
00:28:33,400 --> 00:28:36,300
like beetles and
millipedes and pill bugs.

525
00:28:39,066 --> 00:28:41,542
NARRATOR:
It raises the tantalizing
possibility

526
00:28:41,566 --> 00:28:44,009
{\an1}that this could have been a
winter food source

527
00:28:44,033 --> 00:28:48,276
{\an1}for Alaskan dinosaurs, as well.

528
00:28:48,300 --> 00:28:51,576
CHIN:
Herbivorous dinosaurs
like Ugrunaaluk

529
00:28:51,600 --> 00:28:54,042
might also have
been feeding on rotting wood

530
00:28:54,066 --> 00:28:57,042
{\an1}during the four months of the
year or so when

531
00:28:57,066 --> 00:28:59,633
{\an1}they had the polar winter.

532
00:29:02,466 --> 00:29:04,942
NARRATOR:
With the arrival of winter,

533
00:29:04,966 --> 00:29:09,000
{\an1}darkness is one problem
for the Alaskan dinosaurs.

534
00:29:10,333 --> 00:29:14,866
{\an1}They also face much colder
temperatures.

535
00:29:16,633 --> 00:29:19,376
What in their
physiology allowed them

536
00:29:19,400 --> 00:29:21,609
to remain in Alaska,
shielding them

537
00:29:21,633 --> 00:29:24,033
from the elements?

538
00:29:26,600 --> 00:29:29,909
{\an7}So for a long time, the image of
a traditional, classic dinosaur

539
00:29:29,933 --> 00:29:32,376
{\an8}was of a very scaly,
very reptilian,

540
00:29:32,400 --> 00:29:35,042
{\an8}almost a monstrous
sort of creature.

541
00:29:35,066 --> 00:29:36,942
{\an1}But lately, dinosaurs have been
getting softer,

542
00:29:36,966 --> 00:29:38,176
{\an1}they've been getting fuzzier.

543
00:29:38,200 --> 00:29:41,109
Like, dare I say it,
they're getting cute.

544
00:29:41,133 --> 00:29:42,676
{\an1}There was a early tyrannosaur

545
00:29:42,700 --> 00:29:46,776
{\an1}that lived about 125 million
years ago named Yutyrannus

546
00:29:46,800 --> 00:29:48,509
{\an1}covered almost head to tail

547
00:29:48,533 --> 00:29:50,742
{\an1}in fluffy feathers, and this
was not a small animal.

548
00:29:50,766 --> 00:29:52,176
This animal was
about 30 feet long.

549
00:29:52,200 --> 00:29:57,609
NARRATOR:
Intriguingly, Yutyrannus
lived in a part of China

550
00:29:57,633 --> 00:30:00,942
{\an1}during the early Cretaceous that
had a cool climate

551
00:30:00,966 --> 00:30:06,509
similar to Alaska
70 million years ago.

552
00:30:06,533 --> 00:30:11,409
{\an7}Most dinosaurs had simple
feathers that looked like hair.

553
00:30:11,433 --> 00:30:13,076
{\an1}Our hair keeps us warm,

554
00:30:13,100 --> 00:30:14,509
{\an1}that's what hair does
in mammals,

555
00:30:14,533 --> 00:30:17,942
{\an1}and for many dinosaurs,
they had these simple feathers

556
00:30:17,966 --> 00:30:21,266
{\an1}probably to keep their bodies
warm.

557
00:30:22,933 --> 00:30:25,142
{\an1}If dinosaurs that were living
in an area

558
00:30:25,166 --> 00:30:28,409
{\an1}of similar temperatures
earlier in the Cretaceous

559
00:30:28,433 --> 00:30:31,576
had all of these
thick coats of feathers,

560
00:30:31,600 --> 00:30:34,642
{\an1}then probably a lot of
the Alaskan dinosaurs did, too.

561
00:30:34,666 --> 00:30:36,276
{\an1}(dinosaurs chirping and lowing)

562
00:30:36,300 --> 00:30:37,542
NARRATOR:
In addition to feathers,

563
00:30:37,566 --> 00:30:41,276
{\an1}Alaskan dinosaurs may have
had other adaptations

564
00:30:41,300 --> 00:30:44,409
for surviving
colder temperatures.

565
00:30:44,433 --> 00:30:47,142
{\an1}One of the interesting groups
of dinosaurs

566
00:30:47,166 --> 00:30:49,909
{\an1}that we have represented in
our fauna

567
00:30:49,933 --> 00:30:52,409
in the Prince Creek
Formation are thescelosaurids.

568
00:30:52,433 --> 00:30:54,542
♪ ♪

569
00:30:54,566 --> 00:30:57,076
NARRATOR:
Thescelosaurids are dwarves

570
00:30:57,100 --> 00:30:59,809
in a land of Alaskan giants.

571
00:30:59,833 --> 00:31:02,876
{\an1}The smaller of two Arctic
species

572
00:31:02,900 --> 00:31:06,509
{\an1}is just 18 inches tall
at the hip.

573
00:31:06,533 --> 00:31:10,009
{\an1}Small creatures lose heat
more rapidly,

574
00:31:10,033 --> 00:31:13,509
{\an1}and they freeze a lot faster.

575
00:31:13,533 --> 00:31:17,533
So how did these
small dinos survive the cold?

576
00:31:21,166 --> 00:31:23,276
A clue can be found

577
00:31:23,300 --> 00:31:25,209
{\an1}in their Montana cousins.

578
00:31:25,233 --> 00:31:29,209
♪ ♪

579
00:31:29,233 --> 00:31:30,942
{\an7}Some species of thescelosaurs

580
00:31:30,966 --> 00:31:35,966
{\an7}were found actually preserved
in a burrow.

581
00:31:37,366 --> 00:31:38,876
{\an1}Up until about 20 years ago,

582
00:31:38,900 --> 00:31:41,433
{\an1}that's not something that
we thought dinosaurs did.

583
00:31:43,300 --> 00:31:45,742
DRUCKENMILLER:
That raises the exciting
possibility that

584
00:31:45,766 --> 00:31:49,342
perhaps the species
of thescelosaurid in Alaska

585
00:31:49,366 --> 00:31:51,642
{\an1}might also have been capable
of burrowing,

586
00:31:51,666 --> 00:31:54,676
and potentially
over-wintering by hibernating.

587
00:31:54,700 --> 00:31:56,742
♪ ♪

588
00:31:56,766 --> 00:32:00,642
NARRATOR:
Feathers and the ability
to burrow

589
00:32:00,666 --> 00:32:03,009
{\an1}aren't the only adaptations that
may have helped polar dinosaurs

590
00:32:03,033 --> 00:32:05,933
{\an1}survive the cold temperatures.

591
00:32:08,566 --> 00:32:10,942
DRUCKENMILLER:
We're finding a very exciting

592
00:32:10,966 --> 00:32:14,876
{\an1}number of bones from troodontids
in the bone bed layer

593
00:32:14,900 --> 00:32:16,842
{\an1}we excavated this winter.

594
00:32:16,866 --> 00:32:18,342
{\an1}And because they're so rare,

595
00:32:18,366 --> 00:32:21,176
{\an1}every single bone that we find
is providing

596
00:32:21,200 --> 00:32:22,742
{\an1}another new piece of the puzzle

597
00:32:22,766 --> 00:32:26,842
in understanding
what this animal was.

598
00:32:26,866 --> 00:32:28,809
♪ ♪

599
00:32:28,833 --> 00:32:32,476
NARRATOR:
Troodontids were lightweight,
fast-moving,

600
00:32:32,500 --> 00:32:35,576
and agile predators

601
00:32:35,600 --> 00:32:39,676
{\an1}with eyes set towards the front,

602
00:32:39,700 --> 00:32:44,976
{\an1}a common adaptation in predators
giving them binocular vision

603
00:32:45,000 --> 00:32:49,009
{\an1}to triangulate small,
scurrying prey.

604
00:32:49,033 --> 00:32:50,642
ERICKSON:
They're raptors, so to speak,

605
00:32:50,666 --> 00:32:55,142
{\an1}and had giant sickle claws on
their second toe,

606
00:32:55,166 --> 00:32:59,742
and clawed hands,
and menacing teeth.

607
00:32:59,766 --> 00:33:03,742
In many ways,
this was a roadrunner from Hell.

608
00:33:03,766 --> 00:33:06,642
♪ ♪

609
00:33:06,666 --> 00:33:08,576
NARRATOR:
But the Alaskan troodontid

610
00:33:08,600 --> 00:33:12,500
{\an1}has one noticeable aspect
that sets it apart.

611
00:33:14,100 --> 00:33:15,476
ERICKSON:
So I'm looking at

612
00:33:15,500 --> 00:33:21,609
{\an1}a adult troodon tooth from
the Prince Creek Formation.

613
00:33:21,633 --> 00:33:24,000
{\an1}And this is a monster,
it's a big one.

614
00:33:27,000 --> 00:33:32,442
{\an1}This tooth is probably
50% longer than we see in

615
00:33:32,466 --> 00:33:36,566
{\an1}Troodon formosus, which is a
species found down in Montana.

616
00:33:38,133 --> 00:33:40,742
{\an1}That suggests this is a
different species,

617
00:33:40,766 --> 00:33:43,342
or same species
got larger up here.

618
00:33:43,366 --> 00:33:47,042
♪ ♪

619
00:33:47,066 --> 00:33:49,642
NARRATOR:
Troodontids that lived
elsewhere

620
00:33:49,666 --> 00:33:52,476
{\an1}stood three feet at the hip.

621
00:33:52,500 --> 00:33:56,842
{\an1}But the Alaskan troodontid
was twice as tall.

622
00:33:56,866 --> 00:33:59,442
{\an1}Why would living in a harsher
environment

623
00:33:59,466 --> 00:34:03,242
{\an1}lead to a larger size?

624
00:34:03,266 --> 00:34:06,309
ERICKSON:
It's been shown with some
mammals and few other birds

625
00:34:06,333 --> 00:34:08,309
{\an1}and a few other creatures
that they get larger

626
00:34:08,333 --> 00:34:10,642
{\an1}when they live closer
to the poles.

627
00:34:10,666 --> 00:34:13,609
{\an7}It's a thermal advantage to
be bigger in a cold environment.

628
00:34:13,633 --> 00:34:16,342
{\an7}You're, you're less likely to
cool down, so to speak.

629
00:34:16,366 --> 00:34:20,842
NARRATOR:
So far, from the
Prince Creek Formation alone,

630
00:34:20,866 --> 00:34:23,809
{\an1}scientists have identified

631
00:34:23,833 --> 00:34:27,909
{\an1}at least 13 unique species
of dinosaurs specially adapted

632
00:34:27,933 --> 00:34:29,842
{\an1}to life in the Arctic.

633
00:34:29,866 --> 00:34:32,909
{\an1}But among all the species found
there,

634
00:34:32,933 --> 00:34:36,609
{\an1}one is of particular interest
to the team.

635
00:34:36,633 --> 00:34:39,109
{\an1}It's an animal that was
originally thought

636
00:34:39,133 --> 00:34:44,476
{\an1}to have evolved to be smaller,
not larger, like the troodontid.

637
00:34:44,500 --> 00:34:48,109
{\an1}That animal came to light
in 2014,

638
00:34:48,133 --> 00:34:49,642
{\an1}when another team of scientists

639
00:34:49,666 --> 00:34:52,076
working at the
Prince Creek Formation

640
00:34:52,100 --> 00:34:55,276
{\an1}announced the discovery
of Nanuqsaurus,

641
00:34:55,300 --> 00:34:57,709
{\an1}the Arctic's apex predator.

642
00:34:57,733 --> 00:35:00,476
{\an1}Ultimately, what this comes down
to is this.

643
00:35:00,500 --> 00:35:03,776
{\an1}T. rex, the most iconic dinosaur
of all,

644
00:35:03,800 --> 00:35:06,942
{\an1}how do you take that type
of animal

645
00:35:06,966 --> 00:35:08,942
{\an1}and move it into the Arctic?

646
00:35:08,966 --> 00:35:10,709
What does it become?

647
00:35:10,733 --> 00:35:15,309
NARRATOR:
Estimated to be half the size
of an adult T. rex,

648
00:35:15,333 --> 00:35:18,809
{\an1}it's labeled a dwarf species.

649
00:35:18,833 --> 00:35:22,809
{\an7}Mysteriously, it comes from
a lineage of giants,

650
00:35:22,833 --> 00:35:25,142
{\an7}but when first discovered,

651
00:35:25,166 --> 00:35:27,976
{\an7}it was thought to have bucked
the evolutionary trend

652
00:35:28,000 --> 00:35:30,709
{\an8}that suggested
tyrannosaurs evolved

653
00:35:30,733 --> 00:35:34,109
{\an8}to become larger
over millions of years.

654
00:35:34,133 --> 00:35:36,076
{\an8}BRUSATTE:
If it's tough to survive there,

655
00:35:36,100 --> 00:35:37,976
{\an7}animals often get smaller.

656
00:35:38,000 --> 00:35:39,976
It's easier to cope
with limited resources

657
00:35:40,000 --> 00:35:42,709
{\an1}if you're getting smaller,
so maybe because the Arctic

658
00:35:42,733 --> 00:35:44,742
{\an1}was a tough place to live...
It was cold, it was dark...

659
00:35:44,766 --> 00:35:47,933
{\an1}the tyrannosaurs could not
get as big there.

660
00:35:50,200 --> 00:35:53,176
NARRATOR:
But these initial findings are
made

661
00:35:53,200 --> 00:35:57,009
on just a handful of
bone fragments.

662
00:35:57,033 --> 00:36:02,500
{\an1}Leading them to wonder, was it
really as small as it looked?

663
00:36:06,066 --> 00:36:08,409
♪ ♪

664
00:36:08,433 --> 00:36:11,442
Pat and the team
haven't identified

665
00:36:11,466 --> 00:36:13,342
{\an1}any new Nanuqsaurus bones

666
00:36:13,366 --> 00:36:15,942
{\an1}from the Colville this time.

667
00:36:15,966 --> 00:36:17,742
{\an1}But there is another place

668
00:36:17,766 --> 00:36:21,800
{\an1}they hope to find evidence.

669
00:36:23,000 --> 00:36:27,642
{\an1}Not with bones, teeth, or
dinosaur droppings, however,

670
00:36:27,666 --> 00:36:30,609
{\an1}but thanks to a different record
of the past

671
00:36:30,633 --> 00:36:34,000
{\an1}preserved in the very ground
they walked on.

672
00:36:36,166 --> 00:36:38,042
Their footprints.

673
00:36:38,066 --> 00:36:41,476
BLACK:
It's not just finding
new species.

674
00:36:41,500 --> 00:36:44,009
{\an1}It's not just tracking these
animals.

675
00:36:44,033 --> 00:36:47,142
{\an1}It's really revealing a world
that we know very little about.

676
00:36:47,166 --> 00:36:48,576
{\an1}It's a unique ecosystem

677
00:36:48,600 --> 00:36:51,509
{\an1}that really doesn't have an
equivalent on our modern planet.

678
00:36:51,533 --> 00:36:56,442
NARRATOR:
Using geological maps,
Pat identifies several

679
00:36:56,466 --> 00:36:59,376
new sites in
Denali National Park where

680
00:36:59,400 --> 00:37:02,409
{\an1}dino prints might be preserved

681
00:37:02,433 --> 00:37:04,809
{\an1}in its Cretaceous rock.

682
00:37:04,833 --> 00:37:07,009
{\an1}Dinosaur tracks were first
catalogued

683
00:37:07,033 --> 00:37:10,076
here in 2005,

684
00:37:10,100 --> 00:37:14,142
{\an1}but they've never been fully
surveyed.

685
00:37:14,166 --> 00:37:15,609
Pat and his team

686
00:37:15,633 --> 00:37:17,742
{\an1}will systematically explore
these sites,

687
00:37:17,766 --> 00:37:20,076
{\an1}deep into the backcountry.

688
00:37:20,100 --> 00:37:24,309
DRUCKENMILLER:
One of the things we're
interested in investigating is,

689
00:37:24,333 --> 00:37:26,942
are dinosaurs
that lived in the polar regions

690
00:37:26,966 --> 00:37:30,209
{\an1}slightly larger than their close
relatives at lower latitudes

691
00:37:30,233 --> 00:37:31,609
or even smaller?

692
00:37:31,633 --> 00:37:35,009
♪ ♪

693
00:37:35,033 --> 00:37:39,876
NARRATOR:
450 miles south of
the Prince Creek Formation,

694
00:37:39,900 --> 00:37:45,576
{\an1}in the Alaska Range, is Denali
National Park and Preserve.

695
00:37:45,600 --> 00:37:50,409
{\an1}Its six million acres
of tundra, boreal forest,

696
00:37:50,433 --> 00:37:53,342
{\an1}and ice-capped mountains
cover an area

697
00:37:53,366 --> 00:37:55,400
equivalent in size
to the state of Vermont.

698
00:38:00,333 --> 00:38:03,942
{\an1}To get to the suspected track
sites, it's a six-mile hike

699
00:38:03,966 --> 00:38:07,709
{\an1}through unforgiving terrain.

700
00:38:07,733 --> 00:38:11,276
{\an1}The only way in is by foot.

701
00:38:11,300 --> 00:38:13,809
{\an1}There are so many things
that can go wrong.

702
00:38:13,833 --> 00:38:15,766
{\an1}You just gotta be really
on top of it.

703
00:38:18,266 --> 00:38:20,042
{\an1}This wilderness is, is
beautiful,

704
00:38:20,066 --> 00:38:23,376
{\an1}but it's beautiful because
it's a very raw place.

705
00:38:23,400 --> 00:38:28,009
♪ ♪

706
00:38:28,033 --> 00:38:29,809
NARRATOR:
During the late Cretaceous,

707
00:38:29,833 --> 00:38:33,342
Denali looked
completely different.

708
00:38:33,366 --> 00:38:37,042
♪ ♪

709
00:38:37,066 --> 00:38:39,809
{\an1}Millions of years of uplift
and faulting

710
00:38:39,833 --> 00:38:42,942
{\an1}have created the stunning
landscape seen today.

711
00:38:42,966 --> 00:38:47,142
♪ ♪

712
00:38:47,166 --> 00:38:51,342
{\an1}On Pat's last expedition
to Denali,

713
00:38:51,366 --> 00:38:54,442
they located
a huge vertical wall,

714
00:38:54,466 --> 00:38:59,700
{\an1}riddled with thousands of tracks
preserved for millions of years.

715
00:39:01,366 --> 00:39:04,009
{\an8}DRUCKENMILLER:
It's multiple layers of rock,

716
00:39:04,033 --> 00:39:05,876
{\an7}and there's over 100 feet

717
00:39:05,900 --> 00:39:08,542
{\an1}of vertical rock section
exposed here, and now

718
00:39:08,566 --> 00:39:10,476
tilted up on end.

719
00:39:10,500 --> 00:39:13,642
{\an1}So we're seeing a story told at
different levels

720
00:39:13,666 --> 00:39:16,109
and through time.

721
00:39:16,133 --> 00:39:20,276
NARRATOR:
Each depression on what
was once flat ground

722
00:39:20,300 --> 00:39:23,076
{\an1}represents a footprint.

723
00:39:23,100 --> 00:39:27,376
Occupying an area
over a football field in size,

724
00:39:27,400 --> 00:39:31,966
{\an1}it's the largest dinosaur track
site in Alaska.

725
00:39:34,466 --> 00:39:37,876
{\an1}Most prints come from one
species,

726
00:39:37,900 --> 00:39:42,366
{\an1}a duck-billed dinosaur
like Ugrunaaluk.

727
00:39:44,533 --> 00:39:48,509
Graduate student
Evan Johnson-Ransom

728
00:39:48,533 --> 00:39:50,809
examines a trackway.

729
00:39:50,833 --> 00:39:52,942
JOHNSON-RANSOM:
One of the most fun things about
duck-billed dinosaurs is

730
00:39:52,966 --> 00:39:57,042
{\an1}that they may have had different
forms of locomotion.

731
00:39:57,066 --> 00:39:58,909
{\an1}Some think that bipeds may have
been for the juveniles,

732
00:39:58,933 --> 00:40:00,576
{\an7}but for the larger adults,

733
00:40:00,600 --> 00:40:02,109
{\an7}it would have been, like,
quadrupedal, however.

734
00:40:02,133 --> 00:40:03,676
{\an7}But the jury's still out,
though.

735
00:40:03,700 --> 00:40:06,266
{\an7}It's really cool to, cool to see
these all in person, though.

736
00:40:07,866 --> 00:40:11,542
NARRATOR:
As well as providing clues
to the animals' locomotion,

737
00:40:11,566 --> 00:40:15,409
{\an1}for science writer Riley Black,

738
00:40:15,433 --> 00:40:18,109
{\an1}trackways also provide
a fascinating glimpse

739
00:40:18,133 --> 00:40:21,309
{\an1}into their behavior and world.

740
00:40:21,333 --> 00:40:22,576
{\an1}These tracks themselves are
fascinating

741
00:40:22,600 --> 00:40:23,876
{\an1}because they're fossilized
behavior.

742
00:40:23,900 --> 00:40:26,776
{\an1}In places like this, where
we have multiple tracks

743
00:40:26,800 --> 00:40:29,776
{\an8}on any given slab,
you start to ask yourself,

744
00:40:29,800 --> 00:40:32,509
{\an7}"Okay, well, why is that?"

745
00:40:32,533 --> 00:40:34,042
{\an1}Oftentimes, you'll have
something like a sandbar

746
00:40:34,066 --> 00:40:35,342
{\an1}or the edge of a lake.

747
00:40:35,366 --> 00:40:38,842
{\an1}That's the best place to sort
of skirt around it,

748
00:40:38,866 --> 00:40:40,742
{\an1}and you'll have animals going
back and forth

749
00:40:40,766 --> 00:40:42,709
{\an1}over time, making these
dinosaur dance floors.

750
00:40:42,733 --> 00:40:46,042
♪ ♪

751
00:40:46,066 --> 00:40:48,509
NARRATOR:
Over the next several days,

752
00:40:48,533 --> 00:40:54,476
{\an1}the scientists continue to probe
the surrounding area.

753
00:40:54,500 --> 00:40:59,776
{\an1}Because not all tracks are easy
to identify with the human eye,

754
00:40:59,800 --> 00:41:03,909
{\an1}the paleontologists use a tablet
equipped with the latest

755
00:41:03,933 --> 00:41:08,309
{\an1}lidar technology to document
each track they find.

756
00:41:08,333 --> 00:41:11,876
{\an7}Scanning the surface of the
print produces

757
00:41:11,900 --> 00:41:15,966
{\an7}a 3D model the scientists
can analyze further.

758
00:41:17,866 --> 00:41:22,209
{\an7}As well as prints that preserve
the impression of a foot,

759
00:41:22,233 --> 00:41:23,609
{\an7}tracks can also survive

760
00:41:23,633 --> 00:41:27,742
{\an8}as natural casts,
made by the material

761
00:41:27,766 --> 00:41:30,876
{\an7}that filled the original
imprint,

762
00:41:30,900 --> 00:41:34,866
{\an7}like this outcropping
that once filled a footprint.

763
00:41:38,366 --> 00:41:40,776
{\an8}DRUCKENMILLER:
These are classic

764
00:41:40,800 --> 00:41:43,809
{\an7}ceratopsid, or horned dinosaur,
footprints.

765
00:41:43,833 --> 00:41:47,076
{\an7}The only kind of ceratopsid
dinosaur that we know of

766
00:41:47,100 --> 00:41:50,442
{\an7}in Alaska is Pachyrhinosaurus
from Northern Alaska.

767
00:41:50,466 --> 00:41:53,042
♪ ♪

768
00:41:53,066 --> 00:41:57,376
NARRATOR:
Ceratopsids are large
plant-eating dinosaurs

769
00:41:57,400 --> 00:42:00,576
{\an1}that stand on four sturdy legs.

770
00:42:00,600 --> 00:42:06,276
{\an1}Pachyrhinosaurus perotorum
is a unique species to Alaska,

771
00:42:06,300 --> 00:42:09,542
{\an1}lacking the large horns typical
of this group.

772
00:42:09,566 --> 00:42:13,509
At seven feet high
and 18 feet long,

773
00:42:13,533 --> 00:42:16,209
{\an1}it could weigh up to four tons.

774
00:42:16,233 --> 00:42:20,933
{\an1}It's bulky and muscular,
like a modern rhinoceros.

775
00:42:31,466 --> 00:42:33,476
NARRATOR:
So far, the scientists

776
00:42:33,500 --> 00:42:37,476
{\an1}have found numerous footprints...
Not just from dinos,

777
00:42:37,500 --> 00:42:40,776
{\an1}but also of flying reptiles
and birds.

778
00:42:40,800 --> 00:42:43,276
{\an1}And they've discovered

779
00:42:43,300 --> 00:42:45,609
{\an1}an abundance of tracks
from plant-eaters,

780
00:42:45,633 --> 00:42:48,676
{\an1}sharing the land and the food

781
00:42:48,700 --> 00:42:50,776
it has to offer.

782
00:42:50,800 --> 00:42:56,276
{\an1}Where there are herbivores,
there are usually predators,

783
00:42:56,300 --> 00:42:58,633
but where are they?

784
00:43:03,600 --> 00:43:07,742
The team ascends
the mountains of Denali,

785
00:43:07,766 --> 00:43:13,166
{\an1}looking for evidence of Alaska's
Cretaceous carnivores.

786
00:43:14,433 --> 00:43:15,709
DRUCKENMILLER:
The more different

787
00:43:15,733 --> 00:43:17,676
{\an1}track types that you can record,

788
00:43:17,700 --> 00:43:20,509
the more likely you
are to figure out

789
00:43:20,533 --> 00:43:22,542
at least some
broad sense of diversity

790
00:43:22,566 --> 00:43:24,442
of the dinosaurs

791
00:43:24,466 --> 00:43:25,576
{\an1}and of other creatures,
like birds

792
00:43:25,600 --> 00:43:27,676
and possibly flying reptiles.

793
00:43:27,700 --> 00:43:30,042
{\an1}And that's one of our
big questions at this site,

794
00:43:30,066 --> 00:43:31,043
is, who was here?

795
00:43:31,067 --> 00:43:35,276
♪ ♪

796
00:43:35,300 --> 00:43:37,709
NARRATOR:
In Denali, the team

797
00:43:37,733 --> 00:43:40,742
{\an1}identifies a promising site.

798
00:43:40,766 --> 00:43:41,942
The surface appears

799
00:43:41,966 --> 00:43:46,000
{\an1}to have been trampled on by
a large creature.

800
00:43:46,933 --> 00:43:48,809
{\an1}To get a closer look,

801
00:43:48,833 --> 00:43:51,876
Pat and Greg decide
to descend the cliff face.

802
00:43:51,900 --> 00:43:53,533
(grunts)

803
00:43:58,000 --> 00:44:03,500
♪ ♪

804
00:44:06,066 --> 00:44:08,866
NARRATOR:
They scan the trackway.

805
00:44:09,866 --> 00:44:12,009
{\an1}DRUCKENMILLER (laughs):
Look at that.

806
00:44:12,033 --> 00:44:15,042
{\an1}ERICKSON:
It's almost like we, we use our
eyes to find them,

807
00:44:15,066 --> 00:44:18,766
{\an4}and that to actually see them
better.
(Druckenmiller laughs)

808
00:44:20,900 --> 00:44:22,609
{\an8}NARRATOR:
Back at the top,

809
00:44:22,633 --> 00:44:25,700
{\an7}Pat measure the dimensions
of the prints.

810
00:44:27,566 --> 00:44:31,200
{\an8}DRUCKENMILLER:
Yeah, 59 centimeters,
so that's a big footprint.

811
00:44:32,633 --> 00:44:36,009
{\an1}If I measure the width,
we'll see what we get.

812
00:44:36,033 --> 00:44:37,109
33 centimeters.

813
00:44:37,133 --> 00:44:40,742
{\an1}So the footprint is longer than
it is wide,

814
00:44:40,766 --> 00:44:42,742
{\an7}and each foot was laid down,

815
00:44:42,766 --> 00:44:44,676
{\an7}they're almost purely in a
straight line.

816
00:44:44,700 --> 00:44:50,009
NARRATOR:
All the evidence appears
to point to one creature.

817
00:44:50,033 --> 00:44:54,676
DRUCKENMILLER:
This could very well be from
a tyrannosaur.

818
00:44:54,700 --> 00:44:57,242
{\an1}Which is pretty exciting,
'cause if that's the case,

819
00:44:57,266 --> 00:45:00,376
{\an1}this is, this is the longest
tyrannosaur track site now

820
00:45:00,400 --> 00:45:01,542
{\an1}we've found in the park.

821
00:45:01,566 --> 00:45:05,209
{\an8}♪ ♪

822
00:45:05,233 --> 00:45:08,309
{\an8}NARRATOR:
But the findings are
inconclusive.

823
00:45:08,333 --> 00:45:09,942
{\an7}The prints lack detail

824
00:45:09,966 --> 00:45:12,833
{\an7}to positively identify
the track maker.

825
00:45:16,766 --> 00:45:19,742
{\an1}For a better indication of
a large predator,

826
00:45:19,766 --> 00:45:22,076
{\an1}the scientists need to find
a track

827
00:45:22,100 --> 00:45:24,209
that has preserved
the original features

828
00:45:24,233 --> 00:45:26,700
{\an1}of the dinosaur's foot.

829
00:45:30,866 --> 00:45:32,442
TYLER HUNT:
We got a good one!

830
00:45:32,466 --> 00:45:35,809
NARRATOR:
Exploring the summit
of an outcrop,

831
00:45:35,833 --> 00:45:40,342
{\an1}graduate student Tyler Hunt
makes a surprising discovery.

832
00:45:40,366 --> 00:45:43,709
{\an1}So we have one toe here,
one toe here, and one toe here.

833
00:45:43,733 --> 00:45:46,176
There's a pretty prominent
claw impression here,

834
00:45:46,200 --> 00:45:50,509
{\an7}and then I'm seeing some pads
with a raised area in between.

835
00:45:50,533 --> 00:45:53,309
{\an1}So this count of pads is pretty
indicative

836
00:45:53,333 --> 00:45:56,100
{\an1}of a theropod, along with the
shape of the toes.

837
00:45:58,766 --> 00:46:02,742
NARRATOR:
Its three skinny toes with claws
at their tips

838
00:46:02,766 --> 00:46:05,842
{\an1}points to a carnivore.

839
00:46:05,866 --> 00:46:09,109
{\an1}But which meat-eater is it?

840
00:46:09,133 --> 00:46:11,909
{\an9}HUNT:
The middle toe right here
is really long.

841
00:46:11,933 --> 00:46:13,876
{\an1}Along with this asymmetry,

842
00:46:13,900 --> 00:46:17,433
{\an1}it's pretty indicative of
a tyrannosaurid.

843
00:46:19,066 --> 00:46:22,009
{\an1}It would have been a very big
tyrannosaurid, as well.

844
00:46:22,033 --> 00:46:26,742
NARRATOR:
It's an extremely rare find:
a detailed footprint

845
00:46:26,766 --> 00:46:30,042
of a tyrannosaur.

846
00:46:30,066 --> 00:46:31,942
HUNT:
At least we got the one.

847
00:46:31,966 --> 00:46:33,342
{\an1}Now we know they're here.

848
00:46:33,366 --> 00:46:34,542
Absolutely.

849
00:46:34,566 --> 00:46:36,109
{\an1}Got really lucky there.

850
00:46:36,133 --> 00:46:38,009
{\an1}Why couldn't you find it in
a more accessible place?

851
00:46:38,033 --> 00:46:39,076
(laughs):
I know, right?

852
00:46:39,100 --> 00:46:43,942
♪ ♪

853
00:46:43,966 --> 00:46:45,242
NARRATOR:
Back at base camp,

854
00:46:45,266 --> 00:46:48,642
{\an1}Pat and theropod specialist
Evan Johnson-Ransom

855
00:46:48,666 --> 00:46:50,600
analyze the track.

856
00:46:52,300 --> 00:46:56,142
{\an1}Measuring the print reveals
the size of the creature.

857
00:46:56,166 --> 00:46:59,842
{\an8}50 centimeters, so that is
a very big theropod.

858
00:46:59,866 --> 00:47:01,176
{\an7}That's a big theropod.

859
00:47:01,200 --> 00:47:02,642
DRUCKENMILLER:
Doing the standard method

860
00:47:02,666 --> 00:47:05,576
{\an1}of four times the foot length

861
00:47:05,600 --> 00:47:08,742
would put us at at least a
two-meter hip height.

862
00:47:08,766 --> 00:47:10,209
In that other track site,

863
00:47:10,233 --> 00:47:13,176
{\an1}you found footprints of a large
duck-billed dinosaurs,

864
00:47:13,200 --> 00:47:15,576
{\an1}and so those duck-billed
dinosaurs were probably prey

865
00:47:15,600 --> 00:47:16,809
{\an1}to this large tyrannosaurid.

866
00:47:16,833 --> 00:47:18,876
DRUCKENMILLER:
They, they were top dog, right.

867
00:47:18,900 --> 00:47:20,209
{\an5}Oh, definitely.
(laughs):
Yeah.

868
00:47:20,233 --> 00:47:21,342
DRUCKENMILLER:
That was no small predator.
(laughs)

869
00:47:21,366 --> 00:47:22,709
JOHNSON-RANSOM:
Yeah.

870
00:47:22,733 --> 00:47:25,366
There's no way this is
a pygmy tyrant.

871
00:47:26,666 --> 00:47:30,209
NARRATOR:
Cretaceous Alaska's apex
Arctic predator

872
00:47:30,233 --> 00:47:34,166
{\an1}is the so-called dwarf
tyrannosaur Nanuqsaurus.

873
00:47:36,433 --> 00:47:39,309
{\an1}Over the last several years,
researchers at

874
00:47:39,333 --> 00:47:42,642
{\an1}the Museum of the North have
collected and catalogued

875
00:47:42,666 --> 00:47:46,200
{\an1}dozens of its bones from the
Prince Creek Formation.

876
00:47:48,866 --> 00:47:51,509
{\an1}Their new investigations in
the North Slope

877
00:47:51,533 --> 00:47:53,942
{\an1}shed light on the true size of

878
00:47:53,966 --> 00:47:56,776
{\an1}this mysterious carnivore.

879
00:47:56,800 --> 00:47:59,109
In the imaging lab,

880
00:47:59,133 --> 00:48:03,900
{\an1}researcher Zack Perry scans
a vertebra by laser.

881
00:48:05,766 --> 00:48:07,733
{\an1}Then digitally enlarges it.

882
00:48:09,900 --> 00:48:11,642
{\an8}What we've noticed
is that these are

883
00:48:11,666 --> 00:48:13,509
{\an8}much larger
bones than initially thought.

884
00:48:13,533 --> 00:48:15,976
{\an7}These would not fit a dwarf
tyrannosaur model.

885
00:48:16,000 --> 00:48:20,476
NARRATOR:
So just how big is
Nanuqsaurus?

886
00:48:20,500 --> 00:48:23,242
{\an1}Zack examines a tooth

887
00:48:23,266 --> 00:48:27,409
also recovered from
the Prince Creek Formation.

888
00:48:27,433 --> 00:48:29,742
This is about
a three-inch-long tooth.

889
00:48:29,766 --> 00:48:31,609
This is a massive tooth.

890
00:48:31,633 --> 00:48:33,276
It is more the size of an
Albertosaurus

891
00:48:33,300 --> 00:48:34,409
or a Gorgosaurus tooth,

892
00:48:34,433 --> 00:48:36,700
which are definitely not
dwarf tyrannosaurs.

893
00:48:38,000 --> 00:48:41,876
From this, we can infer a
similar size to those species

894
00:48:41,900 --> 00:48:43,376
{\an1}which are about 30 feet long,

895
00:48:43,400 --> 00:48:45,142
maybe about
a two-meter hip height,

896
00:48:45,166 --> 00:48:46,542
so much, much larger

897
00:48:46,566 --> 00:48:49,276
{\an1}than the initially described
size Nanuqsaurus.

898
00:48:49,300 --> 00:48:52,209
♪ ♪

899
00:48:52,233 --> 00:48:55,342
NARRATOR:
This is a tyrannosaur to rival
the biggest carnivores.

900
00:48:55,366 --> 00:48:57,042
(growling)

901
00:48:57,066 --> 00:48:59,409
{\an1}Nanuqsaurus would have had a
mouth full of these teeth.

902
00:48:59,433 --> 00:49:00,709
They're very large

903
00:49:00,733 --> 00:49:04,109
{\an1}and they have these serrations
for tearing flesh

904
00:49:04,133 --> 00:49:05,300
off of its prey.

905
00:49:08,200 --> 00:49:11,209
♪ ♪

906
00:49:11,233 --> 00:49:12,809
(roaring)

907
00:49:12,833 --> 00:49:14,276
NARRATOR:
With an estimated bite force

908
00:49:14,300 --> 00:49:18,309
{\an1}of 4,000 pounds, Nanuqsaurus is

909
00:49:18,333 --> 00:49:20,333
{\an1}the top predator in the Arctic.

910
00:49:22,300 --> 00:49:26,276
To catch its food,
it could use its serrated teeth

911
00:49:26,300 --> 00:49:30,442
{\an1}to tear flesh off its prey,
likely causing it

912
00:49:30,466 --> 00:49:32,142
to bleed to death.

913
00:49:32,166 --> 00:49:36,476
(dinosaur growling)

914
00:49:36,500 --> 00:49:37,642
♪ ♪

915
00:49:37,666 --> 00:49:41,309
{\an1}For the dino hunters, the new
finds

916
00:49:41,333 --> 00:49:43,676
{\an1}help illuminate this lost world

917
00:49:43,700 --> 00:49:47,500
and paint a picture
of its wider ecosystem.

918
00:49:48,966 --> 00:49:54,833
♪ ♪

919
00:49:59,866 --> 00:50:03,309
To support such
a big apex predator,

920
00:50:03,333 --> 00:50:05,242
{\an1}the environment must have had
more food,

921
00:50:05,266 --> 00:50:08,176
{\an1}more flora and fauna,

922
00:50:08,200 --> 00:50:11,276
{\an1}than thought possible
at such an extreme latitude.

923
00:50:11,300 --> 00:50:13,709
♪ ♪

924
00:50:13,733 --> 00:50:15,309
DRUCKENMILLER:
Pretty much everything we found

925
00:50:15,333 --> 00:50:17,442
{\an1}bones of in Northern Alaska,

926
00:50:17,466 --> 00:50:20,066
{\an1}we're finding footprints of very
similar-looking creatures here.

927
00:50:22,200 --> 00:50:24,709
ERICKSON:
We see things like duck-billed
dinosaurs,

928
00:50:24,733 --> 00:50:28,576
{\an1}horned dinosaurs, small and
large meat-eating dinosaurs.

929
00:50:28,600 --> 00:50:31,176
{\an1}And even things like birds.

930
00:50:31,200 --> 00:50:34,542
DRUCKENMILLER:
This must have been a very
productive landscape,

931
00:50:34,566 --> 00:50:37,442
{\an1}home to a really interesting
and diverse set of organisms

932
00:50:37,466 --> 00:50:41,109
{\an1}that called Denali home
70 million years ago.

933
00:50:41,133 --> 00:50:44,009
♪ ♪

934
00:50:44,033 --> 00:50:45,342
NARRATOR:
The fossils recovered

935
00:50:45,366 --> 00:50:48,776
{\an1}from the Prince Creek Formation,

936
00:50:48,800 --> 00:50:52,742
{\an1}along with the Denali tracks,
give us a compelling glimpse

937
00:50:52,766 --> 00:50:55,276
of a rich ecosystem

938
00:50:55,300 --> 00:51:00,133
{\an1}and the incredible adaptability
of these Arctic dinosaurs.

939
00:51:02,166 --> 00:51:03,542
{\an1}Here during the warmer months,

940
00:51:03,566 --> 00:51:07,542
{\an1}the landscape is a spectacular
sight,

941
00:51:07,566 --> 00:51:11,233
{\an1}covered in hundreds of
dino nests.

942
00:51:12,933 --> 00:51:15,042
{\an1}With thousands of dinosaurs

943
00:51:15,066 --> 00:51:20,676
{\an1}of different species feasting
on an abundance of plants

944
00:51:20,700 --> 00:51:24,742
{\an1}and animals, with extraordinary
adaptations

945
00:51:24,766 --> 00:51:27,342
{\an1}to survive and thrive

946
00:51:27,366 --> 00:51:31,542
in this lost world

947
00:51:31,566 --> 00:51:35,942
{\an1}of Alaskan dinosaurs.

948
00:51:35,966 --> 00:51:37,242
♪ ♪

949
00:51:37,266 --> 00:51:38,976
BRUSATTE:
Evolution is always

950
00:51:39,000 --> 00:51:41,776
{\an1}operating to fine-tune organisms

951
00:51:41,800 --> 00:51:44,076
{\an1}to their environment.

952
00:51:44,100 --> 00:51:45,242
BLACK:
The finds here

953
00:51:45,266 --> 00:51:48,276
{\an1}are going to help us zero in on
what made

954
00:51:48,300 --> 00:51:49,576
{\an1}these animals so flexible.

955
00:51:49,600 --> 00:51:52,476
{\an1}They weren't really constrained
by the temperatures

956
00:51:52,500 --> 00:51:54,109
on the planet
to a particular zone

957
00:51:54,133 --> 00:51:55,442
{\an1}or a particular range.

958
00:51:55,466 --> 00:51:58,509
{\an1}They lived in almost every
conceivable environment

959
00:51:58,533 --> 00:52:02,976
{\an1}on land, that was one of the
keys to their success.

960
00:52:03,000 --> 00:52:05,876
{\an1}So these Alaskan dinosaurs
are a prime example

961
00:52:05,900 --> 00:52:08,542
{\an1}of life finding a way.

962
00:52:08,566 --> 00:52:10,733
♪ ♪

963
00:52:32,833 --> 00:52:37,776
{\an8}♪ ♪

964
00:52:37,800 --> 00:52:39,509
{\an8}ALOK PATEL:
Discover the science
behind the news

965
00:52:39,533 --> 00:52:41,442
{\an7}with the "NOVA Now" podcast.

966
00:52:41,466 --> 00:52:44,909
{\an7}Listen at pbs.org/novanowpodcast

967
00:52:44,933 --> 00:52:48,042
{\an7}or wherever you find your
favorite podcasts.

968
00:52:48,066 --> 00:52:52,142
{\an8}ANNOUNCER:
To order this program on DVD,
visit ShopPBS

969
00:52:52,166 --> 00:52:55,109
{\an7}or call 1-800-PLAY-PBS.

970
00:52:55,133 --> 00:52:57,976
{\an7}Episodes of "NOVA" are available
with Passport.

971
00:52:58,000 --> 00:53:02,142
{\an7}"NOVA" is also available on
Amazon Prime Video.

972
00:53:02,166 --> 00:53:07,400
{\an8}♪ ♪

973
00:53:21,600 --> 00:53:26,700
{\an8}♪ ♪