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For over a hundred years,
we've lived with the image.

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A six-ton death machine
called Tyrannosaurus Rex.

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But today, the real nature of this
beast is at the center of a debate.

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In the Badlands of Montana,

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a maverick paleontologist is
on the trail of a mystery.

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Come with me,
we'll go back down to the Cretaceous.

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Jack Horner is determined to crack
open the secrets of a monster.

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Even if that means turning the world
of T Rex inside out.

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Can you see where we are?

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We have grown up
believing that T Rex is a predator

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and it's just hard to
get over that hump.

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Jack Horner is on the trail of
a 65-million-year-old mystery

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in search of
the real Tyrannosaurus Rex.

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In a lost world where nature
and nightmare converge,

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giant creatures rule
the Earth and sky.

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While their reign spans millions of
years, life is measured by the minute.

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Survival depends on how big you are,
how fast you are

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and the size of your teeth.

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Only one beast is feared by all.

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Smart, savage, insatiable.

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1 5 feet tall and 40 feet long,
T Rex can crush a car in its jaws.

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Summer is dinosaur hunting season,

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and paleontologist Jack Horner
is on his way to work.

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And what Horner is finding,
sets him apart

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from a hundred years
of popular belief.

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For years people have gotten the idea
that Tyrannosaurus Rex

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was this big predatory dinosaur.

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We see it in the toys
and in the movies

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and in the books that we read.

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Tyrannosaurus is always trying to
eat everything else in sight.

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I think it's an interesting idea.

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It's interesting, except
scientifically speaking no one's ever

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challenged the idea
that T Rex was a predator.

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And in fact, no one ever even had
evidence to suggest that

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it was a predator.

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I got together with
a group of students

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and decided to look at T Rex
as though no one knew

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what it had ever done for a living.

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We just started looking at
the evidence and seeing

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what the evidence said about T Rex.

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And we came up with
a whole bunch of characteristics

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that seemed to be very supportive of
T Rex being a scavenger

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rather than a predator.

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And yet, no one likes that idea.

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In fact, T Rex the predator has
never been more popular.

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And the challenge to Jack Horner
never so great.

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Was T Rex a vicious killing machine?

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Was it the cold-hearted butcher
we love to hate?

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Challenging the deadly reputation of
T Rex is nothing less than heresy.

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Jack Horner has come to
look for answers

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in the fossil remains
that lay scattered

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in the parched landscape of
the Hell Creek formation.

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As part of an ambitious
five-year project,

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Horner is working to piece together
a comprehensive vision of what life

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was like at the end of
the Cretaceous period.

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Dinosaurs existed,
there's no question about that.

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We have the bones of dinosaurs.

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We have their skeletons.

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We have their footprints.
We have their skin impressions.

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There's an awful lot of stuff
we know about them as fact.

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But when it comes to
figuring out what dinosaurs

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were like as living creatures...

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...how they walked,
what color they were

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we don't know.

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We are sort of at the mercy of
our own imaginations.

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And so we are always trying to
figure out new things

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about these animals by
finding out what's wrong

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with our present hypotheses.

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Hell Creek, Montana is nature's window
into the distant past.

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Getting to this part of the word means
leaving the paved roads hours behind

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then traveling where
there are no roads at all.

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It's June. Excavations begin on
a newly discovered T Rex.

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We are now capable of getting into
areas where people

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wouldn't normally go.

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And the Tyrannosaurus Rex is
a very good example.

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It is way out there.

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It's about as far away from a road
and water as you can get.

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After almost 65 million years,

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the land has eroded back to the time
of the cretaceous,

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revealing the world where
Tyrannosaurus Rex lived and died.

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Actually, you want to give us
some slack, we are almost out of rope.

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Okay. Wait. Hold on.

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Hold on. Wait.

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At the end of the last digging season

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a few promising bones were found
sticking out of

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the bottom of this hill.

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But Winter closed in
before the fossils could be freed.

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When we first found the site,
when we first found the T Rex,

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there was actually a little sandstone
sitting over the top of this.

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What we did was we uncovered
just a little bit of it

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and we found both legs, and part of
the tail going back into the hill,

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so they put a winterjacket
over the top of it

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and now they are going to take off
a whole bunch of dirt.

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Using pick axes, shovels and drills,
the team carefully removes

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the two stories of overburden
that entomb the precious remains.

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Since Tyrannosaurus Rex
was first discovered,

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only two-dozen skeletons
have ever been found.

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None with all of its bones.

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No one has ever found
a complete T Rex,

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and one of the things that
we're missing is a tail

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and this particular specimen that
we're digging up right now

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looks as though there's
a very good chance of

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finding a complete tail.

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Just over a century ago,
Hell Creek produced

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the world's very first T Rex.

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The skeleton uncovered by fossil
collector Barnum Brown

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was far from complete,

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but enough bones remained to cobble
together a prehistoric nightmare.

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It was named Tyrannosaurus Rex,
or Tyrant Lizard King.

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When Barnum Brown discovered T Rex,

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it had already been established
that dinosaurs were reptiles.

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So, when T Rex was put together

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and mounted in the American Museum,

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it was built just like the reptilian
model they expected it to fit.

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They stood it up, put its tail down
on the floor,

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got its head way up in the air.

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Made it just look about
as mean as it could be.

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With claws like meat hooks, a massive
jaw bristling with deadly teeth

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and spare parts borrowed
from other dinosaurs,

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Brown created the Frankenstein monster
of the Cretaceous Age.

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How could they know
to make this T Rex stand up straight,

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they were breaking its back,
neck and tail?

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Yet for most of the 20th Century,

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Tyrannosaurus Rex was seen
as the savage, upright predator

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that Barnum Brown imagined.

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It wasn't until recently that
scientific advances were reflected

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a new posture for T Rex.

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Still, the popular image of
the legendary predator remains.

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For Horner, that image was
shattered for good in 1990.

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An amateur fossil hunter
named Kathy Wankel

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brought a few peculiar looking bones

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to Jack's Museum of he Rockies
in Bozeman, Montana.

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The lives of Jack Horner
and Tyrannosaurus Rex

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would never be the same.

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It was obvious right away
that it was a Tyrannosaurus Rex arm.

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The first one ever found.

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And I was just...
I was almost beside myself.

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I mean, it was really neat to see.

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And the first thing that struck me
was how short the ulna

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and the radius were.

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Within weeks, an expedition was
dispatched to excavate

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the world's tenth Tyrannosaurus Rex.

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And what they unearthed was
the most complete T Rex

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skeleton ever found.

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With over 90% of its bones,

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the Wankel fossil offered the world
the first set of T Rex arms.

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Jack wondered why nature would endow
an aggressive, bloodthirsty predator

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with such pint-sized limbs.

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When predatory animals fight,
they have to be able to jump around.

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They tip over, they hit the ground,
they jump back up again,

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they fight some more.

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Tyrannosaurus Rex couldn't do that.

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The most striking thing about
T Rex' arm other than the fact

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that it's really tiny is the fact that
that the proportions are out of whack.

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I mean, you've got the upper arm bone
the humerus bone,

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which is pretty long,

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and the two lower arm bones,
the ulna and radius,

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which are really short.

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And you look at your own arm
and you'll see that the humerus

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and ulna and radius
are about the same length.

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And that gives us good grasping power.
We can do lots of things with that.

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But T Rex couldn't do that
kind of thing.

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When you look at the arm,

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it's actually longer than
it is in real life.

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In real life, just this hand basically
is sticking out of its body.

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The rest of
it's all encased in muscle.

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So imagine Tyrannosaurus Rex
with its tiny little arms.

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Can't grab anything.
Can't even put its hands together.

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Can't reach its mouth.

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Can't do anything but
scratch its belly.

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And here are people talking about
T Rex as being a predator.

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An animal weighing 12,000 pounds,

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having a center of gravity
that's 12 feet off the ground,

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If it tips over it has no way
of catching itself,

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which it doesn't because of
its short arms.

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It would die.
It would break its jaws.

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Break its ribs.

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T Rex is an animal that just really
cannot afford to fall down.

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Is this the fate of
the tyrant lizard king?

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Some believe what ultimately killed
T Rex rained down

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from the heavens 65 million years ago.

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An asteroid some six miles wide
crashed into the Gulf of Mexico,

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blasting dust and debris into
the upper atmosphere.

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Lethal clouds blocked the sun

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and set in motion the mass extinction
of the dinosaurs.

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Evidence of that catastrophe is seen
today in a thin layer of iridium

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that covers the globe.

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Iridium, an element rare on Earth
but common in asteroids,

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is found in rocks and sediment that
are 65 million years old.

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For dinosaur hunters, this geological
reference point marks the end of

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the Cretaceous Period.

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It's called the K/T Boundary

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So, right here, this dark area
right here, this is the K/T Boundary.

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This is the end of the dinosaur reign.

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So everything below us,
we can find dinosaurs in.

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Everything above it,
there are no dinosaurs.

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So as we go up and down in section,
paleontology really is just,

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is like time travel.

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But you have to have a very good
background in geology to know

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where you are in time.

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Otherwise you are lost in time.

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Come with me,
we'll go back down to the Cretaceous.

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The Cretaceous Period spanned
almost 80 million years.

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During that time, dinosaurs lived
and died at the edge of

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an enormous sea

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that flooded most of North America.

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As the sea withdrew, mountains formed.

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Violent storms and floods deposited
layers of rock and sediment,

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entombing the remains of a lost world.

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00:15:08,507 --> 00:15:09,769
Over millions of years,

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wind, water and erosion shaped
the canyons and valleys of

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present-day Hell Creek,

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00:15:15,180 --> 00:15:18,980
teasing to the surface the long
buried evidence of prehistoric life.

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00:15:22,488 --> 00:15:26,481
But finding the hidden clues is
a slow and painstaking process,

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where the struggle takes place
one step at a time.

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00:15:41,941 --> 00:15:44,409
This area that we're walking
around in right now...

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...has probably never been prospected.

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People have probably never been here,
actually looking for dinosaurs.

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It takes an awful lot of work
to find something good.

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Because we could walk all through
this whole thing and,

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you know, maybe we'll...

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You know, we found an ostrich
vertebrae, two of them,

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and that's good.

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That's good for the amount of time
we've been here.

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So we're doing okay.

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You might say that Jack
was destined for dinosaurs.

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At age eight he found his first fossil

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and his childhood passion
became a lifelong journey.

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While Jack searches for new clues,

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his team on the other side
of the valley

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continues to chip away the hillside

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still hoping the T Rex beneath
will provide a complete tail.

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Even when you find something,
it can be under 1 5 feet of rock,

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and so, you get very excited
when you find something,

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but then you've got to be kind of
patient about it,

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because it might take you all Summer
to actually see it.

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As the crew moves slowly down,

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Jack returns to the museum to
reexamine the evidence of

238
00:16:59,685 --> 00:17:02,085
the 65-million-year-old mystery.

239
00:17:07,426 --> 00:17:11,055
The predator-scavenger debate really
is very exciting

240
00:17:11,997 --> 00:17:15,296
because we can only answer
this question by having lots

241
00:17:15,434 --> 00:17:16,628
and lots of data,

242
00:17:16,769 --> 00:17:18,703
and the data has got to
come from the field

243
00:17:18,837 --> 00:17:20,464
and it's got to
come from the laboratory.

244
00:17:20,606 --> 00:17:22,005
It's got to come from both places.

245
00:17:44,997 --> 00:17:48,558
Once again, the Wankel skeleton
is the source for clues to

246
00:17:48,700 --> 00:17:50,895
the predator-scavenger controversy.

247
00:17:52,604 --> 00:17:56,040
Tyrannosaurus Rex is the largest
meat-eating dinosaur that

248
00:17:56,175 --> 00:17:57,767
ever lived in North America.

249
00:18:00,345 --> 00:18:05,442
But the dinosaurs that I think
are the good predatory dinosaurs,

250
00:18:05,584 --> 00:18:10,044
things like Deinonychus and
Velociraptor, and Sauronithelestes

251
00:18:10,189 --> 00:18:10,985
and so forth,

252
00:18:11,123 --> 00:18:12,215
are all small.

253
00:18:12,825 --> 00:18:15,225
They were small, agile animals,

254
00:18:15,360 --> 00:18:17,885
built very different
than Tyrannosaurus Rex.

255
00:18:22,668 --> 00:18:25,432
Can researchers determine that
any dinosaur was a killer

256
00:18:25,571 --> 00:18:26,765
from its skeleton?

257
00:18:33,679 --> 00:18:38,207
If you look at Sauronitholestes or
any of the animals like Velociraptor,

258
00:18:38,350 --> 00:18:43,617
they have big arms.
Big, long, grasping arms.

259
00:18:44,089 --> 00:18:46,956
Good, long fingers.

260
00:18:47,392 --> 00:18:51,886
Re-curved claws, big claws for
hanging on to things.

261
00:18:52,564 --> 00:18:54,031
They've got a long foot.

262
00:18:54,166 --> 00:18:57,863
They've got slashing claws
on the hind feet for actually cutting.

263
00:18:58,003 --> 00:19:02,372
There's no question that they could
slice and dice with their claw hands,

264
00:19:02,508 --> 00:19:03,998
their hands and their feet.

265
00:19:04,576 --> 00:19:09,479
They also have laterally compressed
teeth, very sharp, serrated.

266
00:19:10,482 --> 00:19:13,747
This animal is designed
to kill things.

267
00:19:19,558 --> 00:19:23,153
Can an animal's skeleton reflect
how fast it could run as well?

268
00:19:24,530 --> 00:19:27,590
We know that Sauronitholestes was
one of the fast-running dinosaurs,

269
00:19:27,733 --> 00:19:33,103
and we can tell that because it has
a relatively short femur

270
00:19:33,238 --> 00:19:34,603
compared to its tibia.

271
00:19:35,474 --> 00:19:38,739
The speed of a bipedal animal
can be determined by the ratio

272
00:19:38,877 --> 00:19:40,276
between its two leg bones.

273
00:19:40,913 --> 00:19:44,610
A short thigh and a long shin,
add up to a fast runner.

274
00:19:50,522 --> 00:19:55,550
Using that formula, Jack measures
T Rex's legs to see how fast it was.

275
00:19:59,431 --> 00:20:04,232
When we look at T Rex,
T Rex's thighbone is 50 inches long

276
00:20:05,103 --> 00:20:09,506
and T Rex's shinbone
is only 46 inches long.

277
00:20:12,744 --> 00:20:16,942
So the thighbone is longer than
the shinbone, which is the opposite

278
00:20:17,082 --> 00:20:18,515
of a fast-running animal.

279
00:20:21,253 --> 00:20:27,988
The fact that T Rex has a longer femur
than tibia, and that the dinosaurs

280
00:20:28,126 --> 00:20:31,289
we think of as being fast runners
don't have that,

281
00:20:31,430 --> 00:20:34,866
it's evidence I think
we can use to hypothesize

282
00:20:35,000 --> 00:20:41,599
that Tyrannosaurus Rex was either
a really slow runner orjust a walker.

283
00:20:53,986 --> 00:20:56,079
With legs that
weren't designed for speed

284
00:20:56,221 --> 00:20:58,416
and arms that were basically useless,

285
00:20:58,557 --> 00:21:03,392
Jack hypothesizes that T Rex
wasn't able to kill much of anything.

286
00:21:06,598 --> 00:21:09,396
The evidence keeps pointing Jack
in one direction.

287
00:21:09,901 --> 00:21:12,836
T Rex simply didn't have the tools
to be a hunter.

288
00:21:16,808 --> 00:21:20,642
We have grown up believing that
T Rex is a predator

289
00:21:21,246 --> 00:21:24,613
and it's just hard to get
over that hump.

290
00:21:28,754 --> 00:21:30,949
You know, sixth graders,
fourth graders, I mean,

291
00:21:31,089 --> 00:21:32,556
they are adamant.

292
00:21:32,691 --> 00:21:34,249
I mean, they throw things at me.

293
00:21:34,393 --> 00:21:36,327
I mean, they just
don't believe it at all.

294
00:21:37,729 --> 00:21:41,187
And yet, I grew up with T Rex
being a predator as well.

295
00:21:41,333 --> 00:21:42,459
Now I had little toys.

296
00:21:42,601 --> 00:21:45,365
You know my T Rex always chased
everything else around and ate it.

297
00:21:52,644 --> 00:21:54,441
All I've been trying to do
is get people to think

298
00:21:54,579 --> 00:21:58,037
about doing science objectively,

299
00:21:58,183 --> 00:22:01,414
not starting out with
a preconceived idea,

300
00:22:01,553 --> 00:22:05,717
they can... You know, I don't care
if T Rex was a predator.

301
00:22:06,291 --> 00:22:08,156
Show me some evidence.

302
00:22:11,663 --> 00:22:15,064
Hell Creek will oblige with one of
its oldest secrets

303
00:22:15,200 --> 00:22:16,861
and a priceless opportunity.

304
00:22:20,672 --> 00:22:24,005
Midway into the digging season,
a breakthrough discovery.

305
00:22:24,810 --> 00:22:29,304
A 68-million-year-old T Rex that
stands out from all the rest.

306
00:22:30,816 --> 00:22:33,944
Now Horner and his team
will be able to compare T Rexes

307
00:22:34,086 --> 00:22:36,554
that lived almost
three million years apart.

308
00:22:40,859 --> 00:22:44,056
But first they must free the bones
from the rock and clay.

309
00:22:46,098 --> 00:22:50,125
Named G Rex after Greg Wilson,
the researcher who discovered it,

310
00:22:50,268 --> 00:22:53,135
this is the second T Rex
discovered this summer

311
00:22:53,271 --> 00:22:55,705
and the oldest T Rex ever found.

312
00:22:59,878 --> 00:23:03,211
With surgical care,
the crew removes the age-old sediment.

313
00:23:14,226 --> 00:23:16,057
It's hard to see the bones
in the ground.

314
00:23:16,194 --> 00:23:18,685
There's one right here at our feet.

315
00:23:20,132 --> 00:23:23,499
This is the shinbone.

316
00:23:24,069 --> 00:23:28,301
This is the knee end of the shin.
The upper end of the tibia.

317
00:23:37,082 --> 00:23:39,050
Right here is the thighbone.

318
00:23:39,885 --> 00:23:43,082
And here is the knee joint
end of the thighbone.

319
00:23:46,358 --> 00:23:48,792
Often times when there's mudstone,
bone and the rock

320
00:23:48,927 --> 00:23:50,121
is about the same color.

321
00:23:51,363 --> 00:23:54,799
But you can see the shape of
the rib here.

322
00:23:54,933 --> 00:23:56,867
One here, another one right here.

323
00:23:59,871 --> 00:24:01,839
One under my foot right here.

324
00:24:05,410 --> 00:24:08,243
Basically what we are looking at here
is a partial skeleton of

325
00:24:08,380 --> 00:24:09,506
a Tyrannosaurus Rex.

326
00:24:13,919 --> 00:24:18,083
It's probably not a huge adult,
but with a length probably

327
00:24:18,223 --> 00:24:19,212
about 35 feet.

328
00:24:25,030 --> 00:24:29,057
The specimen died probably out
on a flood plain of

329
00:24:29,201 --> 00:24:32,136
a river and disarticulated.

330
00:24:32,270 --> 00:24:32,964
Came apart.

331
00:24:33,104 --> 00:24:35,072
Bones scattered around a little bit

332
00:24:35,207 --> 00:24:38,768
and it was then covered up
by subsequent flood deposits.

333
00:24:43,715 --> 00:24:46,684
The chances of uncovering
a perfectly preserved skeleton

334
00:24:46,818 --> 00:24:48,115
are almost impossible.

335
00:24:52,157 --> 00:24:55,251
When G.rex died,
its body returned to the earth.

336
00:24:56,995 --> 00:25:00,431
Its neck and head are pulled back
as rigor mortis sets in.

337
00:25:01,132 --> 00:25:04,966
Skin and muscle rot away.
Only the bones remain.

338
00:25:08,139 --> 00:25:11,631
The spring floods could easily
wash away its tiny arms,

339
00:25:12,711 --> 00:25:16,613
or break away its skull separating
at the neck and carrying it off

340
00:25:16,748 --> 00:25:18,181
in one direction or another.

341
00:25:21,253 --> 00:25:24,586
A leg could easily separate as well,
as could the vulnerable

342
00:25:24,723 --> 00:25:25,849
ends of the tail.

343
00:25:27,792 --> 00:25:31,057
The bones are then buried
and compressed under tons of mud that

344
00:25:31,196 --> 00:25:32,561
hardens into rock.

345
00:25:35,567 --> 00:25:38,502
What's left is a giant cretaceous
jigsaw puzzle scattered

346
00:25:38,637 --> 00:25:39,934
in the sediment.

347
00:25:41,640 --> 00:25:43,574
You can't predict
what you're going to find.

348
00:25:43,708 --> 00:25:45,073
You just never know.

349
00:25:45,210 --> 00:25:49,408
You could dig and dig and dig and
find the same old stuff everybody else

350
00:25:49,548 --> 00:25:50,913
found over the years...

351
00:25:51,049 --> 00:25:53,279
...and never come up with a new idea.

352
00:25:53,785 --> 00:25:58,222
Or you might be digging along and
come up with something brand new.

353
00:25:59,324 --> 00:26:04,227
Everything we find here, everything
we uncover, may or may not be a key.

354
00:26:05,096 --> 00:26:09,999
But that's the neat thing about this
whole predator-scavenger debate.

355
00:26:10,135 --> 00:26:12,535
There isn't a single thing that
it's going to tell you

356
00:26:12,671 --> 00:26:13,729
one way or another.

357
00:26:14,306 --> 00:26:15,933
There's just not a smoking gun.

358
00:26:19,878 --> 00:26:22,472
Every part of T Rex must be examined.

359
00:26:26,418 --> 00:26:30,320
To the trained eye, the half-ton
skull of Tyrannosaurus Rex

360
00:26:30,455 --> 00:26:33,219
may provide important clues to
how it survived.

361
00:26:34,125 --> 00:26:39,188
Here are the teeth, the nose,
the eyes, the brain.

362
00:26:40,231 --> 00:26:43,997
Clues to how T Rex survived
in a kill-or-be-killed world.

363
00:26:46,204 --> 00:26:50,140
If we look at a cast of the brain,
what's really obvious is this

364
00:26:50,275 --> 00:26:52,607
very enlarged area at the front.

365
00:26:53,178 --> 00:26:55,305
This is the olfactory lobe

366
00:26:55,914 --> 00:26:59,611
and right here, this small little bump
right here, that's the optic lobe.

367
00:27:00,085 --> 00:27:02,952
And this little thing right here,
that's the optic nerve.

368
00:27:03,555 --> 00:27:08,151
So we can just tell by looking at
the brain cast that Tyrannosaurus Rex

369
00:27:08,293 --> 00:27:10,887
did not have much of a sense of sight.

370
00:27:15,133 --> 00:27:18,569
It certainly wasn't the kind of animal
that could hunt at night

371
00:27:19,104 --> 00:27:23,165
and I doubt very much if it could hunt
very well in the evening

372
00:27:23,308 --> 00:27:24,366
or in the morning.

373
00:27:24,509 --> 00:27:28,605
But we look right here,
the olfactory lobe is huge.

374
00:27:28,747 --> 00:27:32,046
So from this we can see that T Rex
couldn't see well,

375
00:27:32,183 --> 00:27:34,378
but it had a tremendous sense of smell

376
00:27:35,720 --> 00:27:38,780
Perhaps a nearby hospital can help
Horner get an inside

377
00:27:38,923 --> 00:27:40,857
look at T Rex's sense of smell.

378
00:27:44,095 --> 00:27:47,724
Running the fossilized braincase of
Tyrannosaurus through a C AT scan,

379
00:27:47,866 --> 00:27:50,801
gives Jack a new view
of prehistoric anatomy.

380
00:27:52,737 --> 00:27:55,228
What we are going to do now
is just run through C AT scan slices

381
00:27:55,373 --> 00:27:59,673
that go from the opening of its nose
back to the back of its brain.

382
00:28:00,879 --> 00:28:04,542
This right here is actually
the depression that

383
00:28:04,683 --> 00:28:07,174
the olfactory lobes rest in.

384
00:28:09,688 --> 00:28:11,519
And they just keep getting
bigger and bigger.

385
00:28:13,258 --> 00:28:16,125
T Rex has a huge olfactory,
but it's a huge animal.

386
00:28:16,261 --> 00:28:19,162
And so one of the things
that's important to do

387
00:28:19,297 --> 00:28:22,391
is make comparisons with
modern animals that

388
00:28:22,534 --> 00:28:25,059
may or may not have large olfactories.

389
00:28:26,971 --> 00:28:30,236
Today's vulture is one of
the world's premier scavengers.

390
00:28:30,642 --> 00:28:33,577
It can smell a meal up
to 25 miles away.

391
00:28:35,513 --> 00:28:38,812
Like the T Rex, cross-sections of
the vulture's skull

392
00:28:38,950 --> 00:28:41,441
and olfactory lobes
are equally impressive.

393
00:28:41,586 --> 00:28:42,917
Here we see it right here again.

394
00:28:43,988 --> 00:28:47,355
It starts opening up to
a relatively large...

395
00:28:48,760 --> 00:28:51,456
Getting bigger, a lot bigger.

396
00:28:55,734 --> 00:28:58,532
When the two C AT scans
are placed side-by-side,

397
00:28:58,670 --> 00:29:03,300
Jack discovers that T Rex's olfactory
is proportionally equal to that

398
00:29:03,441 --> 00:29:04,373
of the vulture.

399
00:29:05,543 --> 00:29:06,805
Both are huge.

400
00:29:07,812 --> 00:29:11,407
The lesson from all of this
is turkey vultures are scavengers.

401
00:29:11,549 --> 00:29:16,987
And they use their huge olfactory to
smell things at long distances.

402
00:29:18,289 --> 00:29:19,881
T Rex has a huge olfactory.

403
00:29:20,024 --> 00:29:24,893
So our working hypothesis is that
T Rex used this huge olfactory

404
00:29:25,029 --> 00:29:28,157
to sense dead things
long distances away,

405
00:29:29,901 --> 00:29:33,166
and it walked to them and, ate them.

406
00:29:34,806 --> 00:29:37,434
Tyrannosaurus Rex
sniffing out leftovers?

407
00:29:38,510 --> 00:29:42,378
Jack believes the evidence leads
undeniably in that direction.

408
00:29:47,519 --> 00:29:51,888
65 million years later, dinner
is still being served in Hell Creek

409
00:29:52,023 --> 00:29:55,151
and camp manager Larry Boychuk
knows just what to offer

410
00:29:55,293 --> 00:29:56,624
hungry dinosaur hunters.

411
00:29:57,595 --> 00:30:01,861
Some want it rare, some want it alive
some want it dead.

412
00:30:02,700 --> 00:30:05,863
So that's the trick now,
is to try and please everybody.

413
00:30:06,004 --> 00:30:11,840
So, it's a trick in itself.
Just learning, just learning.

414
00:30:25,089 --> 00:30:30,026
I think it's really important that
we use our evidence

415
00:30:30,161 --> 00:30:32,288
and state what the evidence says

416
00:30:32,964 --> 00:30:36,422
and don't go beyond that.
I think that's good science.

417
00:30:37,068 --> 00:30:40,902
I think it's bad science to say that
something may have happened,

418
00:30:41,039 --> 00:30:45,533
that it may... that T Rex may
have been a predator and a scavenger,

419
00:30:46,778 --> 00:30:49,303
because I don't think there's
any evidence for it being a predator.

420
00:30:50,048 --> 00:30:52,778
And until someone comes up
with that evidence,

421
00:30:53,251 --> 00:30:54,775
I don't think we should say that.

422
00:30:56,621 --> 00:30:59,556
The best thing that we could say,
based on the evidence, is that

423
00:30:59,691 --> 00:31:03,787
T Rex was 1 00 percent scavenger.

424
00:31:05,697 --> 00:31:08,564
But there's still a lot more evidence
to be gathered

425
00:31:08,700 --> 00:31:11,760
and the hunting season
is never long enough.

426
00:31:15,406 --> 00:31:19,035
At first light, Jack and
the G Rex crew are back at work.

427
00:31:20,545 --> 00:31:22,570
Like beacons on a faraway shore,

428
00:31:22,714 --> 00:31:25,410
the bones of T Rex guide
Jack Horner ever deeper

429
00:31:25,550 --> 00:31:27,677
into the lost world of the Cretaceous.

430
00:31:28,786 --> 00:31:32,187
He and his crew save hours of
walking to G Rex by cutting

431
00:31:32,323 --> 00:31:33,381
across the lake.

432
00:31:35,326 --> 00:31:37,351
The team excavating the first T Rex

433
00:31:37,495 --> 00:31:40,089
endures a bumpy drive and
an hour hike to their site.

434
00:31:45,737 --> 00:31:47,898
For Jack, time is of the essence.

435
00:31:49,440 --> 00:31:52,238
Montana's summers are short and
the harsh Winters

436
00:31:52,377 --> 00:31:53,867
make fieldwork impossible.

437
00:32:02,086 --> 00:32:05,078
Using a process that hasn't changed
in a hundred years,

438
00:32:05,223 --> 00:32:09,353
the specimens are covered in layers of
plaster, burlap and paper.

439
00:32:09,494 --> 00:32:11,223
''Jackets'' in the dinosaur trade.

440
00:32:12,597 --> 00:32:16,260
If a jacket is too thin,
a fossil can shatter in transit.

441
00:32:16,401 --> 00:32:19,962
Make a jacket too thick and
you'll need a crane to move it.

442
00:32:21,873 --> 00:32:23,135
With time running out,

443
00:32:23,274 --> 00:32:26,801
Jack heads to the first T Rex site to
check on progress there.

444
00:32:27,578 --> 00:32:30,547
Along the way he scours
the landscape for evidence.

445
00:32:31,082 --> 00:32:33,414
But false leads are all too common.

446
00:32:34,252 --> 00:32:36,686
There's a lot of things that look like
bones that are rocks and

447
00:32:36,821 --> 00:32:38,049
a lot of rocks that look like bones.

448
00:32:38,189 --> 00:32:41,647
So it's really important that you know
what you're looking for.

449
00:32:45,096 --> 00:32:48,657
The bone usually is brown
when it's in the ground.

450
00:32:48,800 --> 00:32:53,294
But then when it weathers for a while
it bleaches, so it's white.

451
00:32:53,771 --> 00:32:56,934
And when you look at it real close,
you can see the spongy nature to it.

452
00:32:57,075 --> 00:33:00,511
You can actually see what people
refer to as the marrow.

453
00:33:01,612 --> 00:33:05,309
There's a much different texture to
the bone than there is to the rock.

454
00:33:05,783 --> 00:33:09,310
The orange, the black, brown,
these are all rocks.

455
00:33:09,754 --> 00:33:11,847
So when we're walking
through the hills,

456
00:33:11,990 --> 00:33:13,958
this is all we are looking for.

457
00:33:14,092 --> 00:33:16,583
Places where pieces of bones
have weathered out.

458
00:33:16,728 --> 00:33:17,922
Weathered down the hill.

459
00:33:18,062 --> 00:33:23,659
When we find them, we look at this
and then we just track it up the hill

460
00:33:23,801 --> 00:33:26,770
until hopefully we find
where it's coming from.

461
00:33:26,904 --> 00:33:31,170
But unfortunately, that's a lot easier
said than done.

462
00:33:35,613 --> 00:33:37,604
But sometimes people get lucky.

463
00:33:39,717 --> 00:33:43,118
A few days earlier, while eating lunch
under the shade of this cliff,

464
00:33:43,254 --> 00:33:47,122
a crewmember spotted some odd-looking
bones sticking out of the rocky wall.

465
00:33:48,259 --> 00:33:50,227
The remains of a third T Rex.

466
00:33:54,665 --> 00:33:58,897
This one is in a fine sandstone.
It's uncrushed.

467
00:33:59,037 --> 00:34:02,063
The bone is you know, dark brown.
It's just beautiful.

468
00:34:02,573 --> 00:34:08,239
So even though it's in a nasty place,
it's still very well preserved.

469
00:34:08,379 --> 00:34:10,370
And you know, in a lot of ways,

470
00:34:10,515 --> 00:34:14,975
it's kind of fun to dig up something
like this that's in kind of

471
00:34:15,119 --> 00:34:16,381
a precarious position.

472
00:34:18,856 --> 00:34:22,257
Risking his neck to excavate
this T Rex is tempting,

473
00:34:22,393 --> 00:34:25,328
but Horner puts the dig on hold
until next season.

474
00:34:26,197 --> 00:34:28,722
Jack's plate is already
full this Summer.

475
00:34:32,737 --> 00:34:36,195
Across the valley, the first T Rex
crew also plasters

476
00:34:36,340 --> 00:34:37,739
over the exposed fossil.

477
00:34:38,276 --> 00:34:41,109
Not for transit, but for protection
from the elements.

478
00:34:42,413 --> 00:34:44,973
This dinosaur will not be
coming out this season.

479
00:34:46,117 --> 00:34:49,848
While removing the overburden,
the crew made a startling discovery.

480
00:34:50,788 --> 00:34:53,484
When we got down,
the first thing they found

481
00:34:53,624 --> 00:34:57,560
was this big old hoof-like toe bone,

482
00:34:58,129 --> 00:34:59,653
which is not a Tyrannosaur.

483
00:35:00,698 --> 00:35:05,294
And basically what we have here
is just a really old duckbill dinosaur

484
00:35:05,436 --> 00:35:11,102
that has bone, a bone texture to it
that is identical to a tyrannosauroid.

485
00:35:12,944 --> 00:35:16,436
Mistaken identification is nothing
new in paleontology,

486
00:35:16,581 --> 00:35:20,745
where progress is made as much from
being wrong as from being right.

487
00:35:21,886 --> 00:35:23,148
I think this is great science.

488
00:35:24,021 --> 00:35:27,047
You can't always identify things,
but you want to identify things.

489
00:35:27,191 --> 00:35:29,318
And so you do your best
to identify it.

490
00:35:29,861 --> 00:35:33,729
And if later you learn that your
identification was wrong, it's great,

491
00:35:33,865 --> 00:35:35,799
you've falsified your hypothesis.

492
00:35:37,435 --> 00:35:39,995
Now affectionately called X Rex,

493
00:35:40,138 --> 00:35:44,438
this duckbill may still prove valuable
to the predator-scavenger debate,

494
00:35:44,575 --> 00:35:47,408
since it lived
at the same time as T Rex

495
00:35:47,545 --> 00:35:49,706
and would likely
have been something it ate.

496
00:35:50,982 --> 00:35:53,507
There is no doubt that
this duckbill dinosaur

497
00:35:53,651 --> 00:35:59,351
was a contemporary of
the Tyrannosaurus Rex that

498
00:35:59,490 --> 00:36:01,583
we are working on across the lake.

499
00:36:01,726 --> 00:36:06,527
And so, T Rex was actually feeding

500
00:36:06,664 --> 00:36:10,464
on the carcasses of the duckbill
dinosaurs after they died.

501
00:36:14,605 --> 00:36:18,041
When we're trying to figure out what
T Rex did for a living, what it ate,

502
00:36:18,176 --> 00:36:21,873
the first thing we need to do
is go to the source, go to the teeth.

503
00:36:24,048 --> 00:36:30,044
The teeth of Tyrannosaurus Rex are
the largest meat-eating dinosaur teeth

504
00:36:30,188 --> 00:36:32,053
that we know of anywhere in the world.

505
00:36:32,190 --> 00:36:38,789
Of any, any species of carnivorous
dinosaur T Rex has the largest,

506
00:36:38,930 --> 00:36:41,626
most massive of all the teeth.

507
00:36:43,501 --> 00:36:47,335
The sheer size of these teeth
is the source of both the fascination

508
00:36:47,471 --> 00:36:50,167
and the legend of
the tyrant lizard king.

509
00:36:51,642 --> 00:36:54,770
Jack wants to take a closer look at
the evidence to set

510
00:36:54,912 --> 00:36:56,106
the record straight.

511
00:36:56,747 --> 00:37:01,241
What is it that people have thought
about T Rex that made it a predator?

512
00:37:01,953 --> 00:37:04,478
And when I went back and looked at
the historical records,

513
00:37:04,622 --> 00:37:08,888
the man who named Tyrannosaurus Rex,
he was the guy that decided that

514
00:37:09,026 --> 00:37:09,890
it was a predator,

515
00:37:10,027 --> 00:37:14,521
I guess because for no particular
reason other than it was big

516
00:37:14,665 --> 00:37:15,689
and had big teeth.

517
00:37:17,201 --> 00:37:20,728
While T Rex's enormous teeth have
continued to intimidate people for

518
00:37:20,871 --> 00:37:22,065
over a hundred years,

519
00:37:22,206 --> 00:37:26,108
progress has been slow in determining
exactly how he might have used them.

520
00:37:27,311 --> 00:37:29,575
But then, a remarkable find.

521
00:37:31,382 --> 00:37:35,478
In 1990, a one-of-a-kind fossil
was discovered in Hell Creek

522
00:37:35,620 --> 00:37:38,783
with the equivalent of
65-million-year-old fingerprints

523
00:37:38,923 --> 00:37:39,912
all over it.

524
00:37:41,058 --> 00:37:44,789
The only way we can really tell what
Tyrannosaurus Rex ate

525
00:37:44,929 --> 00:37:48,126
is to find something that was actually
eaten by a Tyrannosaurus.

526
00:37:50,401 --> 00:37:52,528
This right here
is a pretty good example.

527
00:37:52,670 --> 00:37:55,503
This Is the sacrum of a Triceratops.

528
00:37:55,640 --> 00:37:59,804
And this particular sacrum has a bunch
of big puncture marks in it

529
00:37:59,877 --> 00:38:04,109
and those puncture marks just
so happen to be the right size

530
00:38:04,248 --> 00:38:05,840
for a T Rex tooth.

531
00:38:05,983 --> 00:38:09,248
So we can actually see that
a Tyrannosaurus Rex could actually

532
00:38:09,387 --> 00:38:13,483
make the puncture marks that we find
in this particular sacrum.

533
00:38:14,825 --> 00:38:20,764
So this particular bone is evidence
that Tyrannosaurus Rex ate meat.

534
00:38:21,399 --> 00:38:25,233
It's not however evidence that
Tyrannosaurus Rex killed anything.

535
00:38:25,870 --> 00:38:28,065
All we can see here
is bite marks on it.

536
00:38:28,205 --> 00:38:31,333
We can see that T Rex
was a bone crusher.

537
00:38:31,475 --> 00:38:35,104
We could see that when it ate
this animal, the animal was dead.

538
00:38:35,246 --> 00:38:38,113
And we can tell that by the fact that
we've got these deep marks

539
00:38:38,249 --> 00:38:39,944
in the bottom of the sacrum.

540
00:38:41,485 --> 00:38:45,478
The sacrum is located at the bottom of
the spine, encased in gristle.

541
00:38:46,023 --> 00:38:49,390
It's the least accessible bone
on a Triceratops' body

542
00:38:49,527 --> 00:38:52,724
and by logic,
would only have been eaten by T Rex

543
00:38:52,863 --> 00:38:55,832
after all the choicer morsels
had already been consumed.

544
00:38:59,270 --> 00:39:02,000
The clues to
the 65-million-year-old mystery

545
00:39:02,139 --> 00:39:04,039
are beginning to add up for Jack.

546
00:39:04,709 --> 00:39:08,008
From T Rex the predator to
T Rex the scavenger,

547
00:39:08,145 --> 00:39:11,512
smelling its way to dinner and
arriving after predators

548
00:39:11,649 --> 00:39:13,241
have already been served.

549
00:39:15,219 --> 00:39:19,053
T Rex was the kind of animal
that got to a carcass second.

550
00:39:20,157 --> 00:39:23,024
The predators get there first.
They get the meat.

551
00:39:23,160 --> 00:39:26,960
The scavengers get there second and
they have to crush bone.

552
00:39:27,098 --> 00:39:31,899
And T Rex being a bone-crusher,
probably is getting there second.

553
00:39:39,810 --> 00:39:42,745
The emerging image of the new T Rex
is nearly complete.

554
00:39:43,481 --> 00:39:44,880
Filling in the remaining gaps

555
00:39:45,015 --> 00:39:48,246
requires getting this year's evidence
out of the field and safely

556
00:39:48,386 --> 00:39:49,444
back to the lab.

557
00:39:50,855 --> 00:39:52,322
Getting it out
is the most important thing.

558
00:39:52,456 --> 00:39:54,390
I mean, you can work all summer,

559
00:39:54,525 --> 00:39:58,393
but if you don't get it out,
you just had fun is all.

560
00:40:01,065 --> 00:40:03,898
A hundred years ago,
using horses and wagons,

561
00:40:04,034 --> 00:40:07,492
it took weeks for Barnum Brown to get
the plaster-covered remains of

562
00:40:07,638 --> 00:40:09,697
the first T Rex out of Hell Creek.

563
00:40:10,941 --> 00:40:13,808
These days it can be done in
just an afternoon.

564
00:40:16,414 --> 00:40:20,851
For Jack, a season of backbreaking
work hangs in the balance.

565
00:40:24,622 --> 00:40:26,783
This is the oldest T Rex known.

566
00:40:26,924 --> 00:40:28,789
It's found at the bottom
of the formation.

567
00:40:28,926 --> 00:40:31,986
There are no T Rexes anywhere
that are any older than this.

568
00:40:32,129 --> 00:40:36,896
And so, if we re going to see
evolution within Tyrannosaurus Rex,

569
00:40:37,034 --> 00:40:39,400
we're going to see
arms getting smaller.

570
00:40:39,537 --> 00:40:41,471
If we are going to see
leg proportions changing.

571
00:40:41,605 --> 00:40:45,041
If we're going to see the kinds of
features that I think are important

572
00:40:45,176 --> 00:40:46,643
to a scavenging animal.

573
00:40:46,777 --> 00:40:49,337
We're going to see them first
in this thing.

574
00:40:53,117 --> 00:40:56,644
Will the oldest T Rex
ever found fuel the fire

575
00:40:56,787 --> 00:40:59,551
or end the debate
over Tyrannosaurus Rex?

576
00:41:10,868 --> 00:41:14,998
In museums across the country,
dinosaurs are the star attractions.

577
00:41:18,275 --> 00:41:20,106
T Rex gets top billing,

578
00:41:20,244 --> 00:41:23,680
sending chills of delight up
the spines of young and old.

579
00:41:25,182 --> 00:41:29,642
Beneath the display room floor,
the changing face of Tyrannosaurus Rex

580
00:41:29,787 --> 00:41:31,379
is slowly being revealed.

581
00:41:33,524 --> 00:41:37,426
In a dark corner of the museum,
an amazing one-of-a-kind specimen

582
00:41:37,561 --> 00:41:39,620
that has never been seen
by the public.

583
00:41:40,865 --> 00:41:44,562
Called Daspletosaurus,
it's in the tyrannosaur family

584
00:41:44,702 --> 00:41:46,829
and a very close cousin of T Rex.

585
00:41:47,972 --> 00:41:50,998
But what's extraordinary is that
this is a juvenile.

586
00:41:52,142 --> 00:41:54,167
Once freed of it's rocky grave,

587
00:41:54,311 --> 00:41:58,941
the body features of this youngster
may write a new chapter on T Rex.

588
00:42:00,417 --> 00:42:05,411
This juvenile Daspletosaurus
is probably the best example of

589
00:42:05,556 --> 00:42:09,014
a juvenile tyrannosaur that exists
in North America.

590
00:42:09,727 --> 00:42:13,788
So once we get the juvenile out of
the rock, we will take it

591
00:42:13,931 --> 00:42:14,727
to the hospital

592
00:42:14,865 --> 00:42:18,562
and we'll C AT scan it and
look at its olfactory.

593
00:42:18,702 --> 00:42:20,897
And we'll look at it
at the leg proportions.

594
00:42:21,038 --> 00:42:23,131
We'll look at all the stuff
that we would look at

595
00:42:23,274 --> 00:42:26,732
if we were to have,
if we had a baby T Rex.

596
00:42:28,612 --> 00:42:31,137
While a baby T Rex
has yet to be found,

597
00:42:31,282 --> 00:42:33,750
Horner is excited about
the newest addition to

598
00:42:33,884 --> 00:42:35,408
the museum's vast collection.

599
00:42:36,220 --> 00:42:38,882
G Rex, the oldest T Rex in the world.

600
00:42:41,859 --> 00:42:46,956
The skeleton that we call G.rex
is the oldest Tyrannosaurus Rex

601
00:42:47,097 --> 00:42:48,394
that's ever been found.

602
00:42:49,099 --> 00:42:54,469
And we are right now hypothesizing
that it is 68 million years old,

603
00:42:54,605 --> 00:42:59,065
as opposed to all the rest of them
that are around 65 million years old.

604
00:43:00,511 --> 00:43:03,503
The age of a fossil is calculated by
the depth of its

605
00:43:03,647 --> 00:43:04,705
location in the ground.

606
00:43:05,549 --> 00:43:09,508
The Wankel Rex was found close to
the top of the Hell Creek formation...

607
00:43:10,154 --> 00:43:12,679
G Rex was found 300 feet lower.

608
00:43:12,823 --> 00:43:15,553
In earth that is nearly
three million years older.

609
00:43:16,460 --> 00:43:19,657
By comparing specific
bones belonging to the Wankel

610
00:43:19,797 --> 00:43:21,856
with the same bones of G Rex,

611
00:43:21,999 --> 00:43:25,662
Jack can see how Tyrannosaurus Rex
evolved over time.

612
00:43:26,570 --> 00:43:30,506
What we learn from measuring the femur
and the tibia of the older T Rex

613
00:43:30,641 --> 00:43:34,975
is that the femur and the tibia
have basically the same length.

614
00:43:35,980 --> 00:43:39,313
Making a comparison to
the Wankel T Rex,

615
00:43:40,084 --> 00:43:43,076
the Wankel T Rex
has a longer femur than tibia.

616
00:43:43,654 --> 00:43:47,750
Now, I think this is
a very strong indicator.

617
00:43:48,792 --> 00:43:56,858
As T Rex is evolving,
T Rex is losing its ability to run

618
00:43:57,001 --> 00:44:00,767
and acquiring an adaptation for
long distance walking.

619
00:44:02,473 --> 00:44:05,931
The biggest mouth in the world
can't eat what it can't catch.

620
00:44:06,477 --> 00:44:10,914
So why would any predator evolve away
from running towards walking,

621
00:44:12,549 --> 00:44:14,141
unless it was a scavenger?

622
00:44:22,359 --> 00:44:24,589
If we envision T Rex as a scavenger,

623
00:44:24,728 --> 00:44:28,630
then, then we want to give it
some attributes that

624
00:44:28,766 --> 00:44:31,360
we would associate with a scavenger.

625
00:44:31,502 --> 00:44:34,369
You know, when we look at hyenas,
when we look at turkey vultures

626
00:44:34,505 --> 00:44:35,563
or any of the vultures.

627
00:44:36,540 --> 00:44:39,168
They are nasty looking,
they're vile looking.

628
00:44:39,309 --> 00:44:40,936
They are just awful looking.

629
00:44:43,347 --> 00:44:46,612
A nasty appearance
is key to scavenger survival.

630
00:44:46,750 --> 00:44:50,049
It's their primary bluff
in the cutthroat competition for food.

631
00:44:52,089 --> 00:44:55,183
The same rules of engagement applied
in the Cretaceous.

632
00:44:56,460 --> 00:45:00,954
When a Tyrannosaurus, scavenging
Tyrannosaurus, comes up to a carcass,

633
00:45:02,166 --> 00:45:04,726
the first thing it has to do
is chase away whatever is eating it.

634
00:45:06,303 --> 00:45:10,740
So if I were going to paint
a picture of Tyrannosaurus,

635
00:45:10,874 --> 00:45:12,171
it would have a red head.

636
00:45:12,309 --> 00:45:14,072
It would be really gnarly looking.

637
00:45:14,211 --> 00:45:16,509
It would have some pretty
gross features on it.

638
00:45:17,681 --> 00:45:21,640
T Rex would have been big,
nasty and stinky.

639
00:45:22,519 --> 00:45:24,612
That's my idea of T Rex.

640
00:45:37,501 --> 00:45:41,096
For now, dinosaur-hunting season
in Hell Creek is over.

641
00:45:41,872 --> 00:45:44,272
Jack takes advantage of
the final moments for

642
00:45:44,408 --> 00:45:46,103
some last minute prospecting.

643
00:45:47,277 --> 00:45:50,735
And today he gets lucky, very lucky.

644
00:45:51,849 --> 00:45:53,612
It's the last day of the season.

645
00:45:53,751 --> 00:45:55,480
The last hour of the season.

646
00:45:55,619 --> 00:46:04,323
And after an hour out,
we picked up a few cool bones.

647
00:46:05,229 --> 00:46:07,925
They don't look like much,
mostly they're just bone fragments.

648
00:46:08,065 --> 00:46:12,195
But what's really neat
are these two big pieces.

649
00:46:15,939 --> 00:46:20,103
You can see the suture. This is where
the bones actually fit together.

650
00:46:20,244 --> 00:46:23,338
And this right here is the noggin.

651
00:46:23,480 --> 00:46:27,075
This piece right here,
from a Tyrannosaurus Rex skull.

652
00:46:28,152 --> 00:46:31,417
And the fact that they came apart,
that they're in two pieces,

653
00:46:32,189 --> 00:46:34,487
means that it's a juvenile.

654
00:46:36,260 --> 00:46:39,821
So this is a cool thing.
This is a really cool thing.

655
00:46:40,764 --> 00:46:46,532
This is a piece of
a juvenile Tyrannosaurus Rex

656
00:46:47,271 --> 00:46:48,898
and the skull is still in the ground.

657
00:46:52,142 --> 00:46:54,770
It's been a record-breaking season
in Hell Creek

658
00:46:54,912 --> 00:46:57,540
with an amazing eight T Rexes found.

659
00:46:58,282 --> 00:47:01,410
But for now it's time
for Jack to call it quits.

660
00:47:05,789 --> 00:47:08,986
The mysteries that remain
in the ground outnumber those

661
00:47:09,126 --> 00:47:10,218
that have been solved.

662
00:47:10,894 --> 00:47:13,158
But in the savage realm
of the dinosaur,

663
00:47:13,297 --> 00:47:15,197
the balance of power has shifted.

664
00:47:16,366 --> 00:47:21,099
Scientific fact now challenges
the legend of the tyrant lizard king.

665
00:47:53,036 --> 00:47:57,632
The new T Rex really is very different
from the old idea.

666
00:47:58,475 --> 00:48:02,241
We now see an animal
that can't run fast, that's got short,

667
00:48:02,379 --> 00:48:04,074
little arms,
can't really catch anything,

668
00:48:05,182 --> 00:48:10,085
and really is this smarter animal
that is going in

669
00:48:10,220 --> 00:48:13,280
and taking over someone else's kill.

670
00:48:14,625 --> 00:48:16,320
So in order to do that,

671
00:48:16,460 --> 00:48:19,623
it has to be a really
nasty-looking, vile creature.

672
00:49:02,172 --> 00:49:05,938
And as our image of the king of
the dinosaurs continues to evolve,

673
00:49:06,076 --> 00:49:09,170
for Jack Horner,
only the evidence matters

674
00:49:09,313 --> 00:49:13,147
and the secrets that are hidden
in the ''Valley of the T Rex.''