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Over 66 million years ago...

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SCREECHING WAIL

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..our world...

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HIGH-PITCHED CLUCKS

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..was ruled...

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DEEP SNORT

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..by dinosaurs.

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DEEP BELLOW

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HISSES

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The largest animals that have
<font color="

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ROARS

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Today, dinosaur experts
across the globe

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are uncovering the bones
they left behind...

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..allowing us to imagine how these
creatures may have lived...

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..so that we can tell
<font color="

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..can walk again.

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Western Canada.

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Today, a majestic landscape
of snow-capped peaks...

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..turquoise lakes...

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..and mighty rivers...

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..that erode the ancient bedrock.

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The perfect conditions
<font color="

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Here, on the banks of
Red Deer River...

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..palaeontologists from
the University of Alberta...

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..are unearthing the final resting
place of a super-predator.

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Oh, wow. Yeah, that's really nice.

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Looks like a toe claw.
<font color="

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Albertosaurus -
T-rex's deadly cousin.

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These are the remains of a teenager.

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The team calls her Rose.

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Holy cow!

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Oh, wow. It keeps going.

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Inspired by their discoveries...

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<font color="

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In the Late Cretaceous,

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North America is split in two
by a vast inland sea.

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On its western shores,
a sprawling expanse of dense forests

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and rugged coastlines.

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Laramidia.

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A land in crisis.

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<font color="
temperatures down by two degrees.

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A seemingly small change,

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but enough to push the delicate
ecosystem out of balance.

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SQUAWKS

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SHRIEKING CRIES

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Food is scarce.

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Even...

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<font color="

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RUMBLING BREATHS

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Standing two-and-a-half metres tall,

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and weighing in at one tonne...

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..this is Rose...

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..the Albertosaurus.

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It's been a week
since she last ate.

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But in her sights...

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<font color="

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an older cousin of triceratops.

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A chance for Rose
to satisfy her hunger.

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Rose might just be the fastest
land predator on the planet...

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..sprinting at up to 30mph.

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BELLOWS

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ROARS

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<font color="

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At two tonnes, her target
is twice her weight...

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..with horns almost a metre long.

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Rose is starving.

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But the risk of injury
is just too great.

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Dinner will have to wait.

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71 million years later,

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<font color="

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Hey, guys, how's it going?
Hey, Mark, look at this.

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..led by Mark Powers,

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is uncovering Rose's secrets...

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Found new bones! Whoa, no way!

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..piece by piece.

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You couldn't ask for better...

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<font color="
You really couldn't.

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Each day, more remains emerge
from the ground.

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Ohh! Whoa! Oh, my God.

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Yeah! Yeah, clean it off.

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There it is!

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CHEERING

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<font color="
Rose's leg bones.

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Oh, that's so cool.

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Each fossil is exposed and restored,

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allowing the team to delve deeper
into the story of

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this long-lost super-predator.

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This is looking really good.

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<font color="
Christiana Garros

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to examine the bones
from Rose's shin.

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The tibia is not actually that huge,

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compared to some of the bigger
ones I've seen, at least. No.

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Albertosaurus is an older relative
<font color="

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It's about 79cm. OK.

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Something like that.

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..but it's becoming clear
she was a very different beast

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to her more famous cousin.

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So, long limbs, but the ones of
T-rex are quite a bit bulkier,

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<font color="

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Rose kind of really embodies
what Albertosaurus is.

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It's a very legsy animal, especially
compared to things like T-rex,

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which was incredibly huge.
Yeah. Incredibly chunky.

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<font color="

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Still has powerful jaws. Yeah.

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Maybe the optimal amount
of scary for my taste,

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that's for sure. Absolutely.

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But speed was far from
the only weapon

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in the Albertosaurus arsenal.

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<font color="
out of the ground.

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Oh, that's bone.

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But these don't belong to Rose.

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It does look like a bone from
one of the digits.

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And that's definitely
Albertosaurus, right?

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Yeah, absolutely.

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<font color="
a different-sized Albertosaurus.

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This is a huge one.

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Dinosaur hunters have discovered

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as many as 26 individuals
buried here.

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To try and say any piece belongs
to any one individual

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is kind of tough to do,
<font color="

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It's clearly a mass grave
of Albertosaurus,

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where many individuals died
together in this spot.

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And if they died together...

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..they likely lived together, too.

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LOW GROWLING

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In the cave Rose calls home,

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<font color="

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SNIFFS

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GRUNTS

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Albertosaurus are social animals.

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They live and hunt together,

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forming strong, intimate bonds.

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Rose has paired with this male
Albertosaurus the same age.

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A source of comfort...

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<font color="

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It's been over a week since
the Albertosaurus last made a kill.

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And starvation isn't the only
threat hanging over Rose.

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RUMBLING GRUNT

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The matriarch.

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Racked with intense hunger,

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she could turn on her own.

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<font color="
the pecking order.

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If she hopes to survive,

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she'll have to prove herself
when it matters most.

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It's time to go hunting.

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Ready? Let's go.

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Mark's teamed up with dinosaur
<font color="

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They're venturing further up
Red Deer River

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on the hunt for more giants.

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There's some wonderful
prospecting rocks up there.

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They reach an ancient river system,

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dating from the same time
period as Rose.

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<font color="

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We got a rib here.

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..to what might have fed
the Albertosaurus pack.

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Given its cross-section and
its size, maybe Edmontosaurus.

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I'd say Edmontosaurus, yeah.

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Edmontosaurus - a plant-eating,
duck-billed dinosaur.

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<font color="
to 30 feet long.

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Ten metres here. Jeez!

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Yeah. These things were huge.

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But a single Edmontosaurus

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wouldn't feed a hungry pack of
Albertosaurus for long.

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Holy cow!

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<font color="

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At the top of an escarpment...

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Look at the size of these honkers!

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..more fossils.

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Not bone...

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..but footprints.

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You can see, they got
the big front toe

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and the two toes on the side.

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<font color="

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which is classic Edmontosaurus,
duck-billed dinosaur.

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From the pattern of these prints,

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it looks as though these trackways
couldn't have been made

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by a single creature.

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I've got about 16-17 tracks
<font color="

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Today, there are just
a few footprints.

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But when they were created,

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there would have been many,
many more.

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We have lots of footprints from
various different individuals,

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various different ages
<font color="

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so they definitely moved
in herds, lived in herds.

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Yeah. You imagine, like,
herds of wildebeest,

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and these animals were the size
of one to two elephants.

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These fossilised footsteps suggest

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this corner of Canada
<font color="

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TRUMPETING ROARS

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..to one of the most remarkable
sights in Earth's history.

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A migrating Edmontosaurus herd.

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Thousands of plant-eating dinosaurs
moving as one.

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But an individual adult
Edmontosaurus can be

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<font color="
the largest Albertosaurus.

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BIRDSONG

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Working as a pack is the only way
to take down such colossal prey.

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Higher ground will provide
the perfect vantage point...

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..to mount an attack.

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At this time of year,

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<font color="
with Edmontosaurus...

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..but the herds are nowhere
to be seen.

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LOW GROWLING

203
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ROARS

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This is a time of intense
geological upheaval.

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As the continents move...

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00:18:03,560 --> 00:18:06,400
<font color="

207
00:18:09,960 --> 00:18:13,160
Lava and ash engulf the landscape...

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..forcing this Edmontosaurus herd

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00:18:30,080 --> 00:18:32,280
to take a much longer route
north this year.

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They're still many miles away
from the starving Albertosaurus.

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For the pack,
<font color="

212
00:19:09,080 --> 00:19:10,800
But on the horizon...

213
00:19:12,560 --> 00:19:15,000
..Rose spots an opportunity.

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00:19:30,640 --> 00:19:34,240
From the wind-carved rocks
by Rose's dig site,

215
00:19:34,240 --> 00:19:38,640
palaeontologist Colton Coppock
has made an important discovery.

216
00:19:42,320 --> 00:19:44,600
Yeah.

217
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So, here's a bit of the shaft.

218
00:19:46,320 --> 00:19:48,560
<font color="

219
00:19:48,560 --> 00:19:52,800
belonging to one of the most bizarre
creatures of the Cretaceous...

220
00:19:52,800 --> 00:19:54,720
And here's the condyle. What?!

221
00:19:54,720 --> 00:19:56,800
So, it looks like
it might be from a digit.

222
00:19:56,800 --> 00:19:58,720
There's a condyle? Yeah.

223
00:19:58,720 --> 00:20:02,120
<font color="
part of the knuckle joint.

224
00:20:02,120 --> 00:20:05,320
Very nice. I'm afraid to touch it.

225
00:20:05,320 --> 00:20:09,120
Yeah. It's just so small
and so delicate. Yeah.

226
00:20:09,120 --> 00:20:13,760
You can see the internal structure
of the bone right there.

227
00:20:13,760 --> 00:20:15,960
<font color="

228
00:20:15,960 --> 00:20:19,000
tells Mark this bone was
built for flying.

229
00:20:20,880 --> 00:20:22,800
But this was no bird.

230
00:20:22,800 --> 00:20:26,800
Even in birds, the bone is usually
a lot thicker on the outer surface.

231
00:20:26,800 --> 00:20:27,920
This is very strange.

232
00:20:29,440 --> 00:20:31,880
It can only belong to one creature.

233
00:20:34,640 --> 00:20:36,280
SQUAWKING

234
00:20:36,280 --> 00:20:41,720
<font color="
a six-metre wingspan.

235
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Cryodrakon - a giant pterosaur.

236
00:20:57,560 --> 00:21:02,440
They feed on an enormous ammonite
washed up on the spring tide.

237
00:21:09,920 --> 00:21:11,280
SQUAWKS

238
00:21:16,560 --> 00:21:20,920
The cryodrakon would make a fine
meal for Rose and her mate...

239
00:21:23,400 --> 00:21:25,800
<font color="

240
00:21:34,880 --> 00:21:36,360
SQUAWKS

241
00:21:41,040 --> 00:21:43,400
Approaching from downwind,

242
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and with the pterosaurs'
attention on their meal...

243
00:21:47,200 --> 00:21:49,400
..the youngsters close in.

244
00:22:19,000 --> 00:22:20,960
SQUAWKING

245
00:22:22,560 --> 00:22:24,360
SCREECHES

246
00:22:33,960 --> 00:22:36,560
At last, a chance to feed.

247
00:22:53,320 --> 00:22:55,320
But the pair's absence
<font color="

248
00:22:56,760 --> 00:22:58,880
..hasn't gone unnoticed.

249
00:22:58,880 --> 00:23:02,120
RUMBLING GRUNT

250
00:23:17,040 --> 00:23:21,560
Life in an Albertosaurus pack
was fraught with brutality.

251
00:23:24,160 --> 00:23:27,240
And 71 million years later,

252
00:23:27,240 --> 00:23:30,440
this violence is still written
in the bones.

253
00:23:33,320 --> 00:23:37,800
Mark and anatomist Dr Greg Funston
<font color="

254
00:23:37,800 --> 00:23:42,040
one of the largest
Albertosaurus ever discovered.

255
00:23:42,040 --> 00:23:44,840
We do actually get
a few scars along here,

256
00:23:44,840 --> 00:23:46,800
and they're kind of evenly spaced.

257
00:23:46,800 --> 00:23:49,680
Some are raised,
and some are deep gouges.

258
00:23:49,680 --> 00:23:51,400
So, could these be bite marks?

259
00:23:52,600 --> 00:23:56,800
<font color="
Albertosaurus skulls found here

260
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have teeth marks scratched
into the bone itself.

261
00:24:02,760 --> 00:24:06,400
Near your finger, there's a
little gouge in that one, too.

262
00:24:06,400 --> 00:24:09,120
Look at that. That's deep. Yeah.

263
00:24:09,120 --> 00:24:13,000
<font color="
came down from over the top.

264
00:24:13,000 --> 00:24:15,640
That would've required
tremendous amount of force,

265
00:24:15,640 --> 00:24:19,480
from this diving angle, to actually
remove that piece of bone.

266
00:24:19,480 --> 00:24:23,320
Only another Albertosaurus
could inflict this injury.

267
00:24:26,240 --> 00:24:28,560
<font color="
in this ecosystem,

268
00:24:28,560 --> 00:24:31,040
and it's still getting
beaten up day to day.

269
00:24:32,040 --> 00:24:33,760
They're maybe tussling for food,

270
00:24:33,760 --> 00:24:35,480
like you see on the savanna today,

271
00:24:35,480 --> 00:24:37,720
where lions will eat in
a certain order.

272
00:24:39,040 --> 00:24:41,320
You got two hungry Albertosaurus.

273
00:24:41,320 --> 00:24:43,840
<font color="
want to eat first.

274
00:24:43,840 --> 00:24:45,360
Only one can.

275
00:25:15,880 --> 00:25:19,480
RUMBLING GROWL

276
00:25:19,480 --> 00:25:20,960
As pack leader...

277
00:25:23,320 --> 00:25:27,120
..the matriarch is eyeing up
the youngsters' kill.

278
00:25:27,120 --> 00:25:29,280
GROWLING

279
00:25:33,080 --> 00:25:36,280
Rose is determined
to defend her prize.

280
00:25:42,800 --> 00:25:45,280
<font color="

281
00:25:45,280 --> 00:25:48,280
..leaves her in no doubt
who's in charge.

282
00:26:03,240 --> 00:26:05,000
GRUNTS

283
00:26:16,560 --> 00:26:19,520
Hungry and badly wounded,

284
00:26:19,520 --> 00:26:22,080
Rose has learnt a painful lesson.

285
00:26:26,880 --> 00:26:29,000
She'll have to play by the rules

286
00:26:29,000 --> 00:26:30,640
if she wants to survive.

287
00:26:39,800 --> 00:26:43,520
But the evidence coming out
<font color="

288
00:26:43,520 --> 00:26:47,040
not all of the Albertosaurus
behaviour was violent.

289
00:26:51,960 --> 00:26:56,320
Mark and Henry examine one of
the most intriguing discoveries.

290
00:26:57,760 --> 00:27:00,960
Rose's tiny, fossilised arm bones.

291
00:27:02,680 --> 00:27:06,480
So, we got the upper arm here,
and the forearm down there.

292
00:27:06,480 --> 00:27:09,280
<font color="
right?

293
00:27:09,280 --> 00:27:10,920
This is like the palm of the hand.

294
00:27:12,320 --> 00:27:14,880
Nobody's quite sure
what Albertosaurus used

295
00:27:14,880 --> 00:27:16,560
its minuscule arms for...

296
00:27:17,840 --> 00:27:21,480
..but the strange positioning
has given Mark an idea.

297
00:27:21,480 --> 00:27:24,080
It's quite possible
<font color="

298
00:27:24,080 --> 00:27:25,960
was to have a more flared finger,

299
00:27:25,960 --> 00:27:29,240
sticking outwards rather than,
you know, kind of down by the side,

300
00:27:29,240 --> 00:27:30,280
like a chicken wing.

301
00:27:30,280 --> 00:27:32,720
So, if this was my arm, it would
kind of be flared out like that?

302
00:27:32,720 --> 00:27:34,880
Yeah, you'd be kind of doing
<font color="

303
00:27:34,880 --> 00:27:36,920
Almost jazz hands. Yeah, exactly.

304
00:27:36,920 --> 00:27:40,400
So, Albertosaurus is clearly
using its arms for something.

305
00:27:40,400 --> 00:27:43,720
I mean, modern birds have
a wide variety of mating displays

306
00:27:43,720 --> 00:27:46,360
and behaviours. Mm-hm, yeah.

307
00:27:46,360 --> 00:27:50,400
<font color="
useless arms may have been

308
00:27:50,400 --> 00:27:53,400
vital tools for bonding.

309
00:27:53,400 --> 00:27:55,600
So, if you're going to live in
a group, you've got to have ways

310
00:27:55,600 --> 00:27:58,080
of communicating with one another
that go beyond just, you know,

311
00:27:58,080 --> 00:27:59,720
grunting and staring at each other,

312
00:27:59,720 --> 00:28:02,720
<font color="
side by side on the flank,

313
00:28:02,720 --> 00:28:04,200
reassuring one another.

314
00:28:04,200 --> 00:28:06,520
Telling each other,
"It's going to be OK, it's fine".

315
00:28:06,520 --> 00:28:08,640
A morale boost.
Yeah, exactly. Yeah.

316
00:28:35,720 --> 00:28:37,760
SNORTS AND GRUNTS

317
00:28:41,080 --> 00:28:44,600
<font color="
and badly wounded...

318
00:28:46,560 --> 00:28:48,680
..Rose needs comfort.

319
00:28:50,120 --> 00:28:52,560
DEEP GRUNT

320
00:29:01,400 --> 00:29:06,920
The young Albertosaurus take
time out together to groom.

321
00:29:12,320 --> 00:29:14,880
A soothing ritual...

322
00:29:14,880 --> 00:29:16,920
SOFT GRUNTS

323
00:29:20,160 --> 00:29:22,320
..that strengthens their bond.

324
00:29:56,200 --> 00:29:58,240
<font color="

325
00:29:59,520 --> 00:30:03,280
..the pack's luck
may be about to change.

326
00:30:17,120 --> 00:30:20,120
The Edmontosaurus
have finally made it to

327
00:30:20,120 --> 00:30:21,640
their summer feeding ground.

328
00:30:33,600 --> 00:30:37,000
Not a moment too soon for
the starving Albertosaurus.

329
00:30:41,600 --> 00:30:45,040
And despite their young age,
<font color="

330
00:30:45,040 --> 00:30:49,080
and the other youngsters will play
a crucial role in the hunt.

331
00:30:52,400 --> 00:30:55,400
The fate of the whole pack
depends on them.

332
00:31:07,360 --> 00:31:09,560
Close to Rose's dig site,

333
00:31:09,560 --> 00:31:12,320
a remarkable new fossil is emerging.

334
00:31:14,840 --> 00:31:16,240
Wow.

335
00:31:19,800 --> 00:31:21,160
Very cool.

336
00:31:24,440 --> 00:31:26,960
<font color="

337
00:31:26,960 --> 00:31:28,960
Maybe this is the dentary
going in here?

338
00:31:28,960 --> 00:31:30,920
That could be the back part,
yeah.

339
00:31:32,560 --> 00:31:35,360
But this fossil holds
another secret.

340
00:31:35,360 --> 00:31:36,920
What have we got up here?

341
00:31:38,960 --> 00:31:41,360
That looks like enamel.

342
00:31:41,360 --> 00:31:45,280
<font color="

343
00:31:45,280 --> 00:31:47,160
That's incredible.

344
00:31:48,640 --> 00:31:51,480
This is no Edmontosaurus tooth.

345
00:31:52,880 --> 00:31:55,680
This came from a meat-eater.

346
00:31:57,040 --> 00:31:58,600
Albertosaurus tooth?

347
00:32:00,080 --> 00:32:01,720
I think you're right.

348
00:32:01,720 --> 00:32:03,640
And, since we don't have
much of the root,

349
00:32:03,640 --> 00:32:05,520
it was probably lost during feeding.

350
00:32:06,880 --> 00:32:08,800
<font color="

351
00:32:10,480 --> 00:32:13,440
It's clear evidence
that the Albertosaurus pack

352
00:32:13,440 --> 00:32:16,160
did feast on Edmontosaurus.

353
00:32:19,280 --> 00:32:23,840
But it doesn't help explain how they
bought down such enormous prey...

354
00:32:25,640 --> 00:32:28,640
..and what role Rose might
have played in the hunt.

355
00:32:38,960 --> 00:32:42,440
<font color="
from the right leg.

356
00:32:42,440 --> 00:32:46,200
Quite narrow and compact for
an animal that people usually

357
00:32:46,200 --> 00:32:48,560
envision as being huge, huh?

358
00:32:51,000 --> 00:32:54,080
Mark and Christiana investigate
Rose's foot bones...

359
00:32:56,200 --> 00:32:58,960
They get a heck of a lot bigger.

360
00:32:58,960 --> 00:33:02,360
<font color="
bones of a fully-grown adult.

361
00:33:04,880 --> 00:33:09,040
While they're similar in length,
they're a very different thickness.

362
00:33:09,040 --> 00:33:12,120
So, we can see this one
is only about

363
00:33:12,120 --> 00:33:14,440
three-and-a-half centimetres
in width,

364
00:33:14,440 --> 00:33:16,280
<font color="

365
00:33:16,280 --> 00:33:18,680
we have...almost double that.

366
00:33:18,680 --> 00:33:20,960
So, it's about 6cm in width.

367
00:33:20,960 --> 00:33:23,320
Absolutely a beast -
and the same thing can be said

368
00:33:23,320 --> 00:33:24,800
about the other metatarsal.

369
00:33:26,280 --> 00:33:30,400
Rose was almost as tall
as the largest Albertosaurus,

370
00:33:30,400 --> 00:33:32,880
<font color="

371
00:33:32,880 --> 00:33:35,880
She was definitely going to be
much more agile and quick

372
00:33:35,880 --> 00:33:37,360
than these big individuals,

373
00:33:37,360 --> 00:33:40,320
which probably had a lot more
difficulty picking up speed.

374
00:33:43,080 --> 00:33:46,560
Large Albertosaurus were unlikely
to reach high speeds

375
00:33:46,560 --> 00:33:48,320
<font color="

376
00:33:52,960 --> 00:33:56,160
Meaning Rose and the
other youngsters must take on

377
00:33:56,160 --> 00:33:58,240
the most dangerous of jobs.

378
00:34:05,040 --> 00:34:07,280
LOW GROWLING

379
00:34:17,600 --> 00:34:20,840
Rose and her mate
split off from the pack.

380
00:34:26,240 --> 00:34:29,920
As the swiftest runners,
they must identify a target...

381
00:34:34,680 --> 00:34:37,240
<font color="

382
00:34:44,800 --> 00:34:48,800
But they're a fraction of the weight
of the largest Edmontosaurus.

383
00:34:48,800 --> 00:34:50,760
HISSING

384
00:34:58,400 --> 00:35:02,160
Impulsive and inexperienced,

385
00:35:02,160 --> 00:35:06,560
Rose's mate blindly charges
into the herd...

386
00:35:06,560 --> 00:35:08,680
BELLOWING

387
00:35:12,760 --> 00:35:16,160
..trying to take down one of
<font color="

388
00:35:18,640 --> 00:35:20,320
DISTANT ROAR

389
00:35:31,160 --> 00:35:34,200
DISTANT ROAR
SCREECHES

390
00:35:50,240 --> 00:35:53,120
Rose has lost her closest companion.

391
00:36:01,200 --> 00:36:05,880
And each failed hunt brings her
and the rest of the pack

392
00:36:05,880 --> 00:36:07,800
closer to starvation.

393
00:36:22,600 --> 00:36:24,960
BIRDS CALL

394
00:36:30,280 --> 00:36:33,200
<font color="

395
00:36:33,200 --> 00:36:35,000
even in times of adversity.

396
00:36:36,640 --> 00:36:38,880
They were the dominant predator
in Western Canada

397
00:36:38,880 --> 00:36:41,760
for over three million years.

398
00:36:45,120 --> 00:36:47,080
At Rose's dig site,

399
00:36:47,080 --> 00:36:50,480
part of the reason behind
their success might be emerging.

400
00:36:55,720 --> 00:36:57,400
<font color="

401
00:36:57,400 --> 00:36:59,560
An unassuming fragment of bone.

402
00:37:00,760 --> 00:37:02,640
It looks interesting.

403
00:37:02,640 --> 00:37:04,800
I thought it was a rock, actually.

404
00:37:04,800 --> 00:37:07,160
But it's got a pretty
interesting texture.

405
00:37:07,160 --> 00:37:08,720
It looks like Albertosaurus.

406
00:37:08,720 --> 00:37:13,120
And this roughened area looks to me
<font color="

407
00:37:14,520 --> 00:37:16,800
Is this a part of Rose's skull?

408
00:37:20,080 --> 00:37:21,440
That is part of the skull.

409
00:37:21,440 --> 00:37:24,920
It's probably an indication that the
skull is in several pieces at least,

410
00:37:24,920 --> 00:37:27,800
so we'll have to keep our eyes out
for any loose skull bones

411
00:37:27,800 --> 00:37:30,240
that might be scattered about
<font color="

412
00:37:38,040 --> 00:37:39,800
Whoa!

413
00:37:39,800 --> 00:37:41,440
It's Rose's ghost!

414
00:37:47,360 --> 00:37:50,240
The team estimates Rose's skull
would have been about

415
00:37:50,240 --> 00:37:52,080
two-thirds of a metre long.

416
00:37:53,400 --> 00:37:58,280
Big, but not big enough to take down
huge prey like Edmontosaurus.

417
00:38:00,080 --> 00:38:03,120
But maybe she didn't have to.

418
00:38:03,120 --> 00:38:06,320
<font color="
the jawbones of one of

419
00:38:06,320 --> 00:38:08,360
the largest Albertosaurus.

420
00:38:08,360 --> 00:38:10,800
Just look how big
and robust this jaw is.

421
00:38:10,800 --> 00:38:12,920
It's absolutely crazy.

422
00:38:12,920 --> 00:38:15,280
There's quite a few tooth sockets
on this side.

423
00:38:16,480 --> 00:38:18,920
It's the final piece of the puzzle,

424
00:38:18,920 --> 00:38:22,640
<font color="
sophisticated hunting strategy.

425
00:38:22,640 --> 00:38:25,200
Altogether, 68 teeth in the jaw.

426
00:38:26,200 --> 00:38:28,840
Lots of points of entry
into the body,

427
00:38:28,840 --> 00:38:31,720
so, basically, instead of using
the arms to grapple with prey,

428
00:38:31,720 --> 00:38:33,160
it's all about the head.

429
00:38:35,640 --> 00:38:39,360
These jaws were built to
<font color="

430
00:38:40,880 --> 00:38:43,960
A bite force that's probably
upwards of several tonnes.

431
00:38:43,960 --> 00:38:46,320
There's not much that can, you know,
protect itself from that,

432
00:38:46,320 --> 00:38:48,680
once they have their eyes on you.
Yeah.

433
00:38:50,720 --> 00:38:54,640
Rose's speed and the bite force
of these bigger animals...

434
00:38:56,360 --> 00:38:58,400
<font color="

435
00:39:00,120 --> 00:39:03,200
We could say that Rose was
the runner, and this was the muscle.

436
00:39:03,200 --> 00:39:06,360
When Rose got the animals
out on their own,

437
00:39:06,360 --> 00:39:08,920
big predator like this
probably would've come out

438
00:39:08,920 --> 00:39:10,280
and just finished the job.

439
00:39:18,600 --> 00:39:22,160
LOW GRUNTING

440
00:39:29,120 --> 00:39:31,560
<font color="

441
00:39:31,560 --> 00:39:34,040
but she must now work with
the other youngsters

442
00:39:34,040 --> 00:39:36,080
to find the easiest target.

443
00:39:40,640 --> 00:39:43,640
But with one failed hunt already,

444
00:39:43,640 --> 00:39:45,200
the pressure is on.

445
00:39:56,200 --> 00:39:59,080
SNORTS

446
00:39:59,080 --> 00:40:01,200
BELLOWS

447
00:40:11,160 --> 00:40:14,160
Rearing up on their hind legs,

448
00:40:14,160 --> 00:40:16,360
<font color="

449
00:40:16,360 --> 00:40:18,200
BELLOWS

450
00:40:21,320 --> 00:40:23,320
But Rose bides her time...

451
00:40:27,120 --> 00:40:30,120
..until she spots
an older individual.

452
00:40:34,360 --> 00:40:36,720
One that might be weaker
than the others.

453
00:40:42,760 --> 00:40:44,560
BELLOWS

454
00:40:58,920 --> 00:41:01,480
BELLOWS

455
00:41:01,480 --> 00:41:04,360
Rose can't take this
<font color="

456
00:41:07,440 --> 00:41:09,600
But she can steer her prey...

457
00:41:13,200 --> 00:41:16,280
..right towards the killing jaws

458
00:41:16,280 --> 00:41:17,720
of the matriarch.

459
00:41:21,680 --> 00:41:24,040
BELLOWS
SNARLS

460
00:41:24,040 --> 00:41:26,320
But there's still fight
in this old bull.

461
00:41:40,880 --> 00:41:42,520
SCREECHES

462
00:41:47,320 --> 00:41:48,360
GROWLS

463
00:41:50,680 --> 00:41:53,680
<font color="
to perfection.

464
00:41:55,720 --> 00:41:58,440
Finally, the pack can feed.

465
00:42:08,440 --> 00:42:10,280
And this time...

466
00:42:13,360 --> 00:42:16,800
...Rose gets her share
of the spoils.

467
00:42:38,720 --> 00:42:40,520
All right. Who's ready to jacket?

468
00:42:41,640 --> 00:42:43,880
Coming your way!

469
00:42:43,880 --> 00:42:45,680
Grab those.

470
00:42:45,680 --> 00:42:49,560
<font color="
their finds back to the lab...

471
00:42:49,560 --> 00:42:52,720
...to learn more about this
extraordinary creature.

472
00:42:54,280 --> 00:42:57,960
They carefully wrap their
discoveries in protective plaster.

473
00:42:57,960 --> 00:43:01,280
Sorry, everyone in the vicinity
is going to receive plaster

474
00:43:01,280 --> 00:43:03,800
<font color="

475
00:43:08,000 --> 00:43:09,400
One, two, three.

476
00:43:09,400 --> 00:43:10,920
Oh-oh-oh...

477
00:43:10,920 --> 00:43:13,320
It's OK, it's OK, there's lots
of rock, there's lots of rock.

478
00:43:13,320 --> 00:43:16,400
They flip them, ready for
transport back to base.

479
00:43:16,400 --> 00:43:18,880
Perfect. Beautiful.

480
00:43:18,880 --> 00:43:20,280
Now just the third one.

481
00:43:25,960 --> 00:43:28,040
<font color="

482
00:43:28,040 --> 00:43:29,760
Watch your feet, watch your feet.

483
00:43:31,320 --> 00:43:34,120
But some of Rose's remains
are too heavy

484
00:43:34,120 --> 00:43:36,800
to carry down the hillside.

485
00:43:36,800 --> 00:43:39,800
So, Mark has called in
a little help.

486
00:43:41,240 --> 00:43:44,120
Oh...love that sound.

487
00:43:47,080 --> 00:43:48,560
Hold on to your hats!

488
00:43:53,640 --> 00:43:57,920
<font color="
work would be destroyed.

489
00:44:03,360 --> 00:44:05,200
With ropes attached...

490
00:44:09,720 --> 00:44:12,560
..Rose soars through the air.

491
00:44:12,560 --> 00:44:15,080
Go, Rose! Yeah!

492
00:44:35,120 --> 00:44:39,240
But these ancient lands hold
one final surprise

493
00:44:39,240 --> 00:44:40,840
for the dino hunters.

494
00:44:42,240 --> 00:44:44,040
<font color="

495
00:44:44,040 --> 00:44:47,240
Colton has made a
once-in-a-lifetime discovery.

496
00:44:47,240 --> 00:44:50,160
Oh, what? What is that?

497
00:44:50,160 --> 00:44:53,520
Wait, hold on, that's a...
What?! Whoa.

498
00:44:53,520 --> 00:44:55,440
A tiny jawbone.

499
00:45:00,880 --> 00:45:02,480
What's this a jaw of?

500
00:45:02,480 --> 00:45:04,640
<font color="

501
00:45:04,640 --> 00:45:07,080
It's so tiny.

502
00:45:07,080 --> 00:45:10,000
This is a baby Albertosaurus.

503
00:45:10,000 --> 00:45:12,120
That's beautiful. Like a baby.

504
00:45:12,120 --> 00:45:14,400
Yeah, probably only about
a year old.

505
00:45:14,400 --> 00:45:16,760
Think this is the youngest
individual we have.

506
00:45:18,600 --> 00:45:20,920
<font color="
for a sec to make sure

507
00:45:20,920 --> 00:45:23,960
I wasn't hallucinating.

508
00:45:20,920 --> 00:45:23,960
CHRISTINA LAUGHS

509
00:45:25,240 --> 00:45:27,320
Just scratch it like a puppy.
Yeah. Look.

510
00:45:27,320 --> 00:45:28,760
THEY LAUGH

511
00:45:28,760 --> 00:45:31,880
It's more evidence of the success
of the Albertosaurus.

512
00:45:38,080 --> 00:45:42,240
<font color="
one of the pack females.

513
00:45:45,400 --> 00:45:47,880
Perhaps even Rose herself.

514
00:45:53,080 --> 00:45:55,240
LOW GROWLING

515
00:46:01,400 --> 00:46:06,000
As to how Rose died,
we may never know.

516
00:46:06,000 --> 00:46:07,560
Show-and-tell time.

517
00:46:08,720 --> 00:46:11,120
Causes of death rarely fossilise.

518
00:46:12,800 --> 00:46:15,120
<font color="

519
00:46:15,120 --> 00:46:18,040
Wow, the comparison really
pulled it together. Yeah.

520
00:46:18,040 --> 00:46:20,520
It's not even as long as the tooth.

521
00:46:20,520 --> 00:46:22,080
Oh, my God!

522
00:46:30,440 --> 00:46:33,120
And, though her death
is a mystery...

523
00:46:35,360 --> 00:46:38,640
..now at least,
<font color="

524
00:46:38,640 --> 00:46:40,840
of how she may have lived.

525
00:46:52,160 --> 00:46:55,480
Rose, the young Albertosaurus...

526
00:46:57,720 --> 00:46:59,960
..earned her rightful place...

527
00:47:02,600 --> 00:47:05,720
..hunting and surviving...

528
00:47:08,040 --> 00:47:10,280
..with her pack by her side.

529
00:47:30,880 --> 00:47:33,200
Next time...

530
00:47:33,200 --> 00:47:35,640
..a toddler makes a perilous
journey...

531
00:47:39,200 --> 00:47:42,280
<font color="
the largest dinosaur herds

532
00:47:42,280 --> 00:47:43,840
that ever lived...

533
00:47:45,120 --> 00:47:47,320
..in its fight for survival.