Kind: captions
Language: en
foreign
North America the land that we love it
looks pretty familiar don't you think
well think again
[Music]
the crown we walk on is full of
surprises
if you know where to look is it
geologist the Grand Canyon is perhaps
the best place in the world every single
one of these layers tells its own story
about what North America was like
when that layer was deposited so you're
ready for a little time traveling I'm
Kirk Johnson the director of the
Smithsonian National Museum of Natural
History
and I'm taking off on the field trip of
a lifetime
to unlock this
of our continents Inc Eagle passed in
this episode we're going to jump back
millions of years to a North America
that's full of all kinds of unusual
creatures
[Applause]
yikes turning up in the most unexpected
places
the 14 foot long fish in Kansas that's
what I'm telling you
it's a time when much of the Midwest
was under water
[Music]
I'm on the hunt for Clues
to the amazing connection between our
land and everything that's ever lived
here
from the rise of early life when holding
my hands is a fossil it's 2 billion
years old wow through the destruction of
the biggest baddest beasts of all time
it doesn't look like much this layer is
Armageddon
making North America life
right now on Nova
[Music]
foreign
[Music]
North America today is filled with
gleaming cities
almost half a billion people
and still
spectacular wildlife
[Music]
but if we could rewind the clock and
travel back in time millions of years
life on our continent gets a whole lot
Wilder yikes
that makes a grizzly bear look like
nothing
this land is filled with the bones of
some mind-blowing ancient creatures
roamed and swam across a continent that
was completely different from the
familiar place we call home today
when you dig deep and follow the clues
you uncover an incredible fact
that powerful forces in the ground
beneath our feet and the Rocks all
around us have shaped every plant and
animal that's ever lived here
you just have to look to follow the
twists and turns
the ups and the downs
North America's Incredible life story
wow
that's amazing
in an empty corner of Utah lies a very
special landscape
is a crazy thing
[Music]
I'm flying over a remote region called
the caperowitz plateau
exciting places on the continent
I love this place because its rocks
contain a record of one of the most
important chapters in the history of
life in North America
my guide for the day is paleontologist
Joe sertich an old friend from the
Denver Museum of Nature and Science
pretty good place to be a paleontologist
huh this is awesome
[Music]
what makes the caperowitz so amazing for
paleontologists
is that it's jam-packed full of dinosaur
fossils
[Music]
they're sticking out everywhere
look at that all sorts of chunks of
little bone here looks like
this is a great place for using my
favorite little trick for testing
fossils
it actually sticks really hard the
little pores in the bone will try and
pull the water out of your tongue a real
piece of fossil bone will stick really
hard to the tip of your tongue
but Joe hasn't brought me all the way
out here to suck on a few broken bones
he has something much cooler to show me
the cast of a skull belonging to a new
species of dinosaur discovered right
here that Joe helped identify I think
you're gonna like this
whoa look at that
this is the lower jaw
well there's no doubt that guy's a meat
eater
look at that little steak knife in his
face exactly yikes
that makes a grizzly bear look like
nothing
this is a dinosaur called lithrax
Lutheran ax Lutheran ax is a pretty cool
name it actually means the king of Gore
the king of Gore yeah
who came up with that name I did you did
that's one of the things about finding
dinosaurs you get to name them you get
to come up with a name exactly
the really exciting thing about the king
of Gore
is that when you put flesh on the bones
this runx looks a lot like the much more
famous and fearsome Tyrannosaurus Rex
but it's 10 million years older
maybe he was T-Rex's great great
granddaddy
80 million years ago all of North
America
not just the caperowitz was home to
creatures like Lutheran ax
[Music]
and for the next 14 million years
our continent was like a dinosaur movie
set with a cast list featuring some of
the biggest Superstars like T-Rex
the Hadrosaurus and my favorite dinosaur
triceratops
we know this because we find their
fossils all over the place in fact of
all the dinosaur species discovered
worldwide fossils of more than a quarter
of them have been found here in North
America
the big question for me is why
what was it about North America
that made it such a dinosaur Factory
what was the continent like back then
and it could produce such a diverse cast
of Dino characters
well before we can unravel this mystery
we need to understand the intimate
connection between life and the land
the process that's been going on since
life first emerged more than three and a
half billion years ago
long before the dinosaurs roamed the
land
in a time before North America even
existed
[Music]
the Earth was covered almost entirely in
ocean
there's some intriguing evidence for
this link in an unexpected corner of the
North American Plate
[Music]
I've come here to see a rare living
fossil
one that helped change the Earth itself
without it Life as we know it might not
even exist
my guides are Marine scientists Noah
planovsky and Pamela Reed
so what did you think when you first saw
these things
you feel like you've stepped back in
time to early Earth
you'll see it's loving away my whole
life to see these things
but to see anything first we've got to
dive down about 20 feet
where we'll have a brief window of time
before powerful currents threaten to
sweep us away
we're looking for one of the oldest
organisms on our planet
[Music]
but as we descend there's not much sign
of life
[Music]
rocks
actually these rocks are the very things
I've come to see
[Music]
they're called stromatolites and believe
it or not
they're alive
[Music]
you can't see them
just beneath the surface of these
Boulders it's a thin coating of bacteria
over thousands of years these microbes
accumulated
layer after layer of mud and sand
to build Mounds up to eight feet tall
today living growing stromatolites like
these are extremely rare
but these precious examples hold a key
to the evolution of virtually all
complex life
I could stay down here for hours
but the current is getting stronger and
we don't want to get pulled out to sea
that was amazing down there current
really picked up was ripping through
there too and that is actually why
important reason for why we have these
stomatolites and what's what's special
about this spot allows them to be here
well you noticed a very strong current
when we were there all along by that
current and you also noticed there were
sand waves that were going over this
through my lights that sand will
actually bury this to my lights for
months at a time and then unbury them
again and unbury them again and then
that burial is really important to the
existence of the stromatolite
when the sand is Swept Away the
stromatolites are vulnerable to seaweed
and corals that block the Sun
the sand protects them
it keeps away the higher organisms the
seaweeds the Corals in early Earth there
were no corals and seaweeds to compete
so they actually had a much bigger
territory and they dominated the planet
for about 80 percent of Earth history
stromatolites were Kings
that's a long long time to rule
after Madeleine to the earliest
fossilized form of life we've ever found
when I'm holding my hands is a fossil a
stromatolite from North America that's
two billion years old almost 2 billion
years old
so how old do these things actually get
the oldest examples we find are 3.5
billion years old 3.5 billion years I
love it that's time that's 3.5 is almost
three quarters the entire history of the
planet
so these organisms have seen it all
they're a continuous record of Life
thriving on our planet
why were stromatolites so successful
three billion years ago our planet was
almost unrecognizable
covered by enormous oceans there were no
continents just hundreds of small
volcanic islands
belching out huge amounts of carbon
dioxide
substances
like sulfur dioxide and arsenic
which today would suffocate
[Music]
the groups that built stromatolites used
them to their advantage
the really clever thing about these
organisms is they developed a way to
thrive in the conditions back then and
issue that would have been toxic to Life
as we know it today
but how do they do it
find out Noah and I wade into the Slime
of this Shallow Lake
[Music]
this stuff is slippery man
this place is teeming with bacteria
similar to the ones that live on
stromatolites
oh look at that the same type of
organisms that form the stromatolites
are forming these mats looks like kind
of a nasty black lasagna
smells bad too
there's there's also some bubbles coming
off the water it seems like so let's see
what they are all right we have a gas
probe here let's bury it in the
microbial mat gear and see what we get
very uppermost portion
and it's what gas oxygen oxygen this is
coming out of the mat exactly
the waste product the waste product that
transformed our planet is oxygen
oxygen a waste product that's what we
breathe
but these little microbes do the
opposite
they take in carbon dioxide and water
and release oxygen
it's called photosynthesis
chemical reaction at the heart of every
green plant alive on Earth today
dermatolite bacteria to early Earth
[Music]
in a place filled with volcanoes and
water
over the course of more than two billion
years
they pumped out so much oxygen
that the atmosphere changed from what
would have been a deadly poison for us
into something that made it possible for
Life as we know it to exist
[Music]
so these things didn't only just live in
their environment they actually
transformed the environment and made it
livable for other things absolutely
it was a critical Turning Point
now a new kind of life form could
finally join the party
creatures that didn't produce oxygen but
instead consumed it
[Music]
about 640 million years ago
complex life took off with the evolution
of primitive animals like sponges
[Music]
followed a little later by a group of
jellyfish-like creatures called Nigeria
the first animals possess nerves and
muscles
[Music]
over millions of years life grew ever
more complex
fish got a skull and backbone 420
million years ago
[Music]
by this time land had emerged
so it wasn't long before the first
amphibians all themselves out of the
water and onto the shore
this led to the evolution of reptiles
and then
more than 200 million years ago
to the dinosaurs
[Music]
which brings us right back to where we
started
the big mystery
what was it about this continent that
allowed so many kinds of dinosaurs to
thrive
[Music]
you can find one clue right smack in the
middle of the U.S
in the Great Plains of Central North
America
[Music]
for most people a drive across the Great
Plains as an exercise in boredom
for me it's just the opposite it's a
geologist I think about what's beneath
the planes the stories that lie beneath
the Prairie
[Music]
just outside the town of Oakley in
Western Kansas some strange but
spectacular shapes burst up out of the
Plains
they're called Monument rocks
[Music]
this is so cool
The Story Goes that early settlers
crossing the plains use these as
landmarks to help them navigate
[Music]
one of the most amazing things about
this place is how much time it
represents
just one inch of this chalk is 700 years
that means that a foot of the chalk is 8
400 years or roughly the entire duration
of human civilization
there's about 40 feet of this stuff
above me but it's about 300 feet below
me there's literally millions of years
represented in this one place
[Music]
it's a snapshot of a time when North
America was going through some major
changes
[Music]
place is filled with fossils
[Music]
hey Chuck
long time no seeing you yeah hey Barb
how are you doing good to see and nobody
is better at finding them than Chuck
Bonner and Barbara Shelton who've hunted
for fossils in these rocks for over 40
years go find some fossils all right
sounds good oh you do well come on
when I told him I was coming by they
offered to show me their newest
Discovery that's cool that's pretty cool
[Music]
how'd you find this thing Chuck
well I was searching along those slopes
here and found some big bones sticking
out that's cool what did you think when
you first saw this Barb
lots for a little water in here yeah so
let's bring it to life
a little water reveals a skull with some
major league teeth
no question a vicious predator
this was no dinosaur
[Music]
Jaws belong to an 80 million year old
fish called zifactinus
this jaw is huge I mean this must have
been an immense fish
probably close to 14 feet long
14 foot long fish in Kansas namely a
living 14 foot long fish well if you
count you count the the bill on a Marlin
you be we're in Kansas Chuck it's a 14
foot long fish in Kansas yeah sure
[Music]
what is this ancient Marine Predator
doing 750 miles from the nearest ocean
[Music]
well it turns out 80 million years ago
the ocean was here right on top of
Kansas
it was teeing with Mighty Secret
like Chuck and Barbara's 14-foot
surfactivists
[Music]
it was covered in water
[Music]
about 130 million years ago the ocean
began to invade North America
water flooded in formed a massive Inland
Sea up to a thousand miles wide
continent into two land masses
massive larimedia in the West
and Appalachia in the east
[Music]
who would have huge consequences for
life on our continent
especially North America's dinosaurs
[Music]
back in the comparowitz in Utah where
scientists have discovered an amazing
new collection of dinosaurs
paleontologist Joe certage shows me his
latest find from this extraordinary
dinosaur graveyard
that's pretty clearly a horn yep here
you can see where the eye would have
been there's a large section of the horn
coming off
there's the tip of the horn there
it's starting to look more and more like
a brand new species
so Jurassic Park it is
or is here are remarkably different from
other dinosaurs that lived farther north
at the same time
so what is it with all this diversity
from around 100 million years ago
continent was down the middle by the
Inland sea
over time sea levels changed Shifting
the coastline back and forth all the
time
the dinosaurs of North America on their
toes
with their home turf constantly changing
groups of dinosaurs evolved over time
and adapted to their local surroundings
[Applause]
[Music]
[Applause]
Joe and his colleagues have collected an
amazing variety of dinosaurs and fossil
plants
showing how different environments drove
dinosaur diversity
so what you're saying is that these
different environments along the
coastline create different landscapes
for dinosaurs to evolve in exactly we
suspect that these different ecosystems
are driving dinosaur diversification as
dinosaurs and other animals adapt to
their local conditions and that makes
North America a dinosaur Factory exactly
as a paleontologist it's really exciting
to think that 75 million years ago this
land was full of dinosaurs of every
description
they all lived along this huge Inland
Sea that split America down the middle
and created a whole bunch of different
habitats
70 million years ago something dramatic
happened
the great North American Seaway began to
drain away
so what happened to make this in
totally vanish
[Music]
to solve that mystery I've got to head
east from Utah to Colorado
foreign
this place was also once covered by the
vast Inland Sea
[Music]
with a big sky overhead You Can See For
Miles
ah it's really great views up here 360.
but I didn't climb this hill just for
The View
I'm on the hunt for some strange looking
objects
hoping to find right under my feet
that's what I'm looking for but it's not
a very good one
rocks or clues that help explain why
North America's giant Inland Sea
disappeared
here's a pretty good one
[Music]
after rain
the water pools in them like this
[Music]
and the birds come and bathe in these
things and the locals call these things
bird baths but they're actually
something much more interesting than
that
these rocks once contained fossils of
ancient shellfish called ammonites you
can pretty clearly see the shape of the
shell you start in the center here in
spiral it goes all the way out
and in the middle there would have been
a series of Chambers the fleshy part of
the animal would have stuck out of the
shell here and it would have looked
something like a squid or an octopus
for more than 40 million years North
America's Inland sea was filled with
giant ammonites like these
but it's one thing to find marine
fossils in the Flatlands of Kansas
it's another to find them in the
mountains high above Denver
the big question here is what's going on
but I've got an altimeter here and the
altimeter says that I'm
7703 feet above sea level
that means that something took Marine
creatures and brought them to an
elevation that's more than a mile above
sea level
[Music]
it's the same thing that made North
America's Inland Sea disappear
[Music]
and driving it all is the constant
motion of the ground itself
because the surface of our planet is
broken up into pieces that slowly slide
along a conveyor belt of hot rock miles
beneath us at about two inches a year
around 70 million years ago
a piece of crust under the Pacific Ocean
was diving down at the western edge of
North America
we think that it then began to slide
right under the continent
making it rise
forcing it up inch by inch
to create an icon of the North American
landscape
the Rocky Mountains foreign
birth of this Majestic Mountain Range
was the death of North America's great
Inland Sea
as the Rockies began to rise
the land under the Inland sea was forced
up
and all of its Waters drained into what
is now the Arctic Ocean and the Gulf of
Mexico
this left the Marine creatures living in
the Inland sea literally high and dry
it's mind-boggling to think that the
bottom of the sea could be found at the
top of a mountain range but here are all
these fossils they say that it's so
[Music]
the forces under the Earth are so slow
but so relentless
over millions of years they completely
altered the shape and form of the
continent
and change the fates of the millions of
plants and animals that were living
there
very beginning
rocks and life have been intertwined
[Music]
process doesn't always move slowly
[Music]
and change doesn't always come from
Below
as our old friends the dinosaurs were
about to find out
[Music]
so I packed my bags and head north
[Music]
track down a 66 million year old Smoking
Gun
thanks so much
[Music]
oh
these are the North Dakota Badlands
[Music]
thousands of square miles of arid
gullies and Buttes
driving deep into the Badlands here on
what it's called the state highway but
it's actually Gravel Road
and right around us here is What's
called the hell Creek formation it's a
300 foot thick layer of rock that
stretches over four states and it's a
spot that I just keep coming back to
again and again
and here's a cow I'm about to hit
[Music]
I just can't get enough of this place
because hidden in these Hills is
evidence of an earth-shaking
life-changing event
to find it I'm gonna have to do a little
digging
I actually got a couple pieces of fossil
charcoal here
and that's pretty common in these
layered rocks you find evidence of the
ancient world whether it's the mud from
the bottom of the lake
the coal from the swamp or the charcoal
from an engine forest fire
and every layer used to be
the surface of the Earth at a certain
point in time now there's a stack of
these layers and I'm looking for one
layer in particular
one very thin one's very special
one very scary layer
after a few minutes of digging I find
the 66 million year old layer I've been
searching for
[Music]
there it is
right along here
it's a little rusty orange layer
doesn't look like much
but this layer is Armageddon
[Music]
show you why
I need to get in closer
[Music]
what I'll do is just set up my handy
dandy field microscope
[Music]
I'm looking at this layer under the
microscope and what I'm seeing is that
it's actually composed of little round
balls they're about a millimeter in
diameter
and these things are what used to be
little glass beads so what you've got
basically is some sort of geologic
phenomenon that's dropping beads of
glass onto an ancient landscape
so what could have happened here one way
to get a layer of glass beads in the
landscape is to have a violent event
that melts Rock and blast it in the air
as the molten rock flies to the air it
cools into glass and Rains Down on the
landscape as glass beads
all we found in this layer were glass
beads
and the most likely explanation might be
a massive volcanic eruption
foreign but there's something else
hidden within this layer that changes
the story
tiny crystals called shocked quartz
quartz is an extremely common mineral
you can you can find it all over the
planet
[Music]
but when it shows up with these parallel
lines as shocked quartz
that means it's been exposed to huge
amounts of energy
like you get at nuclear test sites
but when this layer of Earth was laid
down there were no atomic bombs
could have made a big enough bang to
shock courts
about 66 million years ago an asteroid
the size of Mount Everest was headed for
Earth
it entered the atmosphere at over 20
times the speed of a rifle bullet
and exploded with more power
than a billion atomic bombs
sending a superheated plume of vaporized
Rock shooting across North America and
over a hundred miles up into space
this cloud of Doom carried droplets of
molten glass and shocked quartz
all the way to where I found them in
North Dakota
and Beyond bringing deaths and
destruction to our planet
but what effect did it have on the
dinosaurs
for the last 30 years it's been pretty
widely thought that one of the main
groups of animals that were the victims
of this event were the dinosaurs
if this is the case
it's useful to have some real scientific
data
[Music]
30 miles down the road is a guy who can
help me with this hey Tyler Tyler Leeson
is a paleontologist who's been digging
up dinosaur fossils in these Badlands
for more than 20 years it's been a long
time buddy yeah how's it going good I
always get in a Dinosaur Land yeah right
what do you get going look at this
here we have a Tesla sword Tyler and his
crew have pulled dozens of dinosaur
skeletons from these rocks
among them big names like triceratops
and Tyrannosaurus Rex all told how many
different kinds of dinosaurs have you
found in this area two dozen we've found
all the major players here it just
happens to be one of the best places in
the world to find dinosaurs right richer
but where do we find these dinosaurs are
they below the impact layer or above
for the asteroid struck or after
so where is the asteroid impact layer
here it's right at the layer of that
Boulder right there
[Music]
so what do you get below that well we
have some really big dinosaurs we have
the big planeting dinosaurs like
triceratops and montessaurus and these
guys over here vasculosaurus
and then the thing that ate those
dinosaurs like T-Rex right
so above the asteroid impact layer what
do you get well we get you know a few
Turtles we get crocodiles some birds a
few lizards and fish
you find any dinosaurs at all above no
dinosaurs above that black line right
there
So Below is dinosaurs and above is no
dinosaurs absolutely right
nobody has ever found dinosaurs above
the asteroid impact layer in North
America or anywhere else in the planet
[Music]
to me that's pretty convinced
that this catastrophic Collision wiped
out the dinosaurs
[Music]
and they weren't the only living things
to suffer
[Music]
it's an amazing fossil Leaf just popped
out of this rock
tap a little bit more expose it
foreign
there's a leaf that hasn't seen the Sun
for 66 million years
you could even see holes in the leaf
where Cretaceous insects fed on the leaf
when it was growing in a forest that was
full of dinosaurs
and it's this world that was terminated
by the impact of the asteroid
[Music]
we lost more than half of the species of
plants
and more than half of the species of
insects he was truly an ecosystem-wide
devastating event
but even with all this Global
destruction
among the survivors was one special
group of animals that managed to hang on
the mammals
it was little mammals not unlike these
Chipmunks that survived the asteroid
impact and they survived because they
had small body size large population
size they could reproduce fast they
lived in Burrows they were almost
pre-adaptive to survive an event like
the asteroid impact
and once the dinosaurs were gone
they had the world to themselves
[Music]
in the millions of years that followed
mammals evolved and
spread and diversified
they felt every imaginable Niche on land
sea
and air
here in North America and all over the
planet
[Music]
but it's the evolution of one particular
group of mammals the primates that's of
special importance to us
but there's a huge mystery
[Music]
today except for some monkeys in Central
America the only primates native to our
continent are us human beings
if you want to see other primates like
gorillas baboons and monkeys you have to
visit a zoo
or come to a place like this
the Duke University lemur Center
[Music]
look how high that thing is going
it's an 80 Acre Site dedicated to the
study and preservation of lemurs
a group of primates that evolved in
Madagascar
[Music]
here they come there's a bunch coming at
me right now
he's eating one peanut in each hand he's
like he's eating ice cream cones
cool
this is awesome to be so close to these
things
[Music]
it's incredible how well they moved to
the forest and to actually see them
moving around the trees we'll go
straight up a tree 40 feet and then jump
probably 25 30 feet between the trees
little guys leap from tree to tree you
quickly realized that almost everything
about primates is perfectly adapted to a
tree-filled environment
and that kind of makes you wonder
we've got plenty of forests here in
North America
why don't we have primates like these
lemurs jumping through our trees
well the fact is we did
and paleontologist Doug Boyer can show
us
[Music]
well that's a nice fossil one example is
now a jumble of Bones encased in a block
of sandstone from Wyoming
this particular accumulation of Bones
happens to be about 48 million years old
there's still a lot of rock on it though
well instead of extracting every bone
physically we can scan it
[Music]
as the scanner gets to work
faint image comes into view
[Music]
now we can see something starting to
come into the world look at that there's
the elbow coming into the view
it's so tantalizing you just see the
sort of shapes in them
from the scan data Doug builds up a full
3d 3D image of the fossil
it reveals an amazing feature
we have some of the hand here here's
some of the finger bones
look how long those fingers are they're
really long
this animal had incredibly long fingers
huh
if we were to scale this animal up to
your size my fingers would be like that
long freakishly long fingers you'd have
fingers that were about nine inches long
wow
those long fingers perfect for grasping
or a Telltale sign of a primate
and thousands of early primate specimens
have been found all over America
[Music]
these little guys are about two feet
long
like the Lemurs they were great tree
climbers and probably lived on fruit
when you watch these guys moving around
the forest you realize what all these
adaptations are for the long fingers the
long toes the tail the ability to jump
when you look at the fossils it's the
same features preserved in the bones it
doesn't take an expert to realize that
those fossils belong to animals that
were like these animals and lived and
moved in forests
so how did all these ancient primates
get here where did they come from
[Music]
56 million years ago
a huge fiery Rift
opened up in what's now the North
Atlantic
an event with dramatic consequences for
North America and our entire planet
[Music]
volcanic eruptions support huge amounts
of lava for thousands of years
releasing colossal amounts of greenhouse
gases like carbon dioxide and methane
like a blanket in the atmosphere that
kept in the heat
leading to an intense period of global
warming
the change the vegetation across North
America
the cool forests covering the north turn
into dense subtropical rainforests
stretching all the way to Alaska
these trees kept their leaves all year
round providing food and shelter for
primates
[Music]
it'd make the leap for
cross a land bridge
a leafy highway to
they hung around for more than 20
million years spreading all over our
continent
s dropped sharply wiping out the
subtropical forests and their leaping
inhabitants
for millions of years nearly all of
North America would remain primate free
then around 14 000 years ago almost a
blank in geological time
a certain two-legged primate made its
entrance
pet primate of course was us
and our arrival changed everything
arrive in America
found a land full of Untold riches
We Have A Whole New World open in front
of them they can move down the coast
full of resources
whales seals deer
and the coastline is like an open
pathway a Gateway into a continent four
billion years in the making
providing us with an enormous geological
bounty
purpose of the earth hidden in the
landscape gold iron
oil and more
harness to build the vast civilization
that surrounds us today
for the first time in the history of
life in North America
here was a species that would not just
adapt to the landscape
but transform it
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thank you
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[Applause]
foreign
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