WEBVTT

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Welcome to North America.

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The most diverse continent on Earth.

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The only place where you can find
every landscape from polar ice cap...

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to baking desert,
and everything in between.

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Whatever the neighborhood, there's a hero
who can make it a home.

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Smart, tough, brave, you name it.

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They all have what it takes to thrive

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in the wildest,
most beautiful continent on Earth.

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Every corner of America
calls for a different kind of hero.

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These are the Teton Mountains of Wyoming.

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The edge of North America's
biggest mountain range, the Rockies.

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With towering peaks and vast forests,

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this is a land of giants.

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But heroes come in all shapes and sizes.

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A red squirrel.

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Yeah, he's small,
but trust me, size isn't everything.

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He's collecting pinecone seeds

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to help feed him through
the long mountain winter ahead.

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He's been hard at work
for two months.

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And he's collected a stash to be proud of.

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With all those savings in the bank,
you might think he could rest easy.

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But life's not that simple.

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A freeloading black bear.

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Darn!

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He's not gonna take this lying down.

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What the...

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Seriously?

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I mean, you got to admire
the squirrel's guts.

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He's taking on a guy
a thousand times his size.

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If he gets too close,
he might end up in a pinecone sandwich.

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He tries the angry holler.

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The blitz defense.

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But dream on.

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The whole stash is gone in minutes.

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A small snack for the thief,

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a big problem for the squirrel.

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He's not defeated, though.

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He finds some new hiding spots.

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As evening falls, he's still hard at work.

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And yet more strangers show up
on his patch.

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Long-eared owls.

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They like to dine out on squirrels.

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Probably a good time to head to bed.

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While he's sleeping,
his worst nightmare comes true.

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Porcupines uncover one of his new stashes.

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And worse still, a grizzly bear,
the greediest thief of them all,

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finds the last of his buried savings.

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Morning brings a scene of...

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carnage.

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All appears lost.

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But here's why this squirrel's a hero.

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Up in a treetop,
he's been gathering a secret supply

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that the big guys didn't find.

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He didn't put all his eggs in one basket.

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Smart thinking,

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just what you need to make it
in the mountains of America.

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Mountain worlds cover one quarter
of our continent.

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From the glacier-carved Yosemite Valley
in the Sierra Nevada...

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to the volcanoes
of the Cascades and Aleutians.

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Most famous of our 300 active volcanoes
is Mount St. Helens.

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And the highest point
in the continent?

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Over 20,000 feet. Denali, in Alaska.

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Up high, the extreme cold
is the biggest challenge for life.

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Drop down to the coast,

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and there's a whole different set
of problems to overcome.

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In the South, thousands of square miles
of wetlands sit just above sea level,

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including the biggest swamp
in all of North America.

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The Atchafalaya in Louisiana.

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It's ruled over by a giant

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that's been around since
the time of the dinosaurs.

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An American alligator,
our biggest reptile.

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Up to 15 feet long, and a half a ton.

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How has her kind survived

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in America's wetlands
for 70 million years?

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Patience.

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She'll wait as long as it takes
to catch her prey.

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It helps that she can go
for two years between meals.

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Eyes and nostrils
on the top of her head

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mean that she can stay hidden underwater
while she looks for food.

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She'll eat just about anything.

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Although today,
she's gunning for a big prize.

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A white-tailed deer.

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The best grazing is right by
the water's edge.

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The younger deer have no experience
of the danger that can lie beneath.

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She has to keep it real slow.

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These guys are too wary.

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Maybe a resting deer
will be easier to approach.

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Over a short distance,

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she can strike five times faster
than a snake.

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Not today.

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But no worries.
She's got all the time in the world.

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It just takes one deer
to make one mistake,

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and she'll be waiting.

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Head north from
the low-lying swamps of the South...

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and you enter the vast American heartland.

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All along the Mississippi River,

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over the spectacular Badlands
of South Dakota,

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open country of plains, rivers,
and forests

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stretch for 3,000 miles.

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All the way to the Arctic,
where North America

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reaches closer to the North Pole
than any other continent.

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In the middle,

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the prairies are the meeting place
for weather from north and south.

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Out here, you got to be ready
for all seasons in a day.

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One minute, it's green all around.

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An hour later, snow everywhere.

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Be prepared for anything,

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whether you're big like a bison...

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...small like a prairie dog...

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or newly arrived for the breeding season.

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Like this burrowing owl.

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The greatest temperature change
ever recorded on Earth in one day

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was on the U.S. prairie,
a 100-degree swing.

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Sunny and warm again.

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And now, it's raining.

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The heartland heroes are used to it.

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Whatever!

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This hard-working prairie dog mom
takes it all in her stride.

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She's got demanding kids to worry about.

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You know the feeling.

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Out here, though,
it pays to keep one eye on the weather.

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There's no mountains to block winds
blowing from north or south.

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So when the winds shift

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and freezing cold air from the Arctic
meets baking hot air from the tropics,

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things get nasty.

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Up above the prairie dog town,

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the most violent type of thunderstorm
on Earth is forming.

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A supercell.

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The warm air is pushing up
through the cold at 100 feet per second,

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* water vapor with it.

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The thundercloud can climb
to twice the height of Mount Everest.

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The low rumble of a storm
alerts animals for miles around.

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In the most extreme supercells,

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the movement of warm and cold airstreams
creates a spinning vortex.

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The birth of one of
the planet's most destructive forces.

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A tornado.

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Over 1,000 touch down here every year.

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If you've got a burrow,
use it now.

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Wind speeds can hit
over 300 miles per hour,

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the strongest winds on Earth.

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Tornadoes are getting
more widespread as our climate warms.

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A big challenge for people,

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but for the burrow dwellers
of the Great Plains,

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a tornado is just a minor inconvenience.

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Mama prairie dog
gets straight on with rebuilding

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the front porch.

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She even gets the kids to help out.

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But wait, is that another change
in the wind?

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Oh, man!

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The heroes at the heart
of our continent

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endure the planet's wildest weather.

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Travel out
to the sunny California coast,

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and the challenges for life
are way different.

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Just offshore from Los Angeles,
there's a special breed of hero.

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Dolphins.

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The secret to their success?

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Teamwork.

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There are more dolphins
per square mile here

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than anywhere else on Earth.

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A gang like this can be 10,000 strong.

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Every one of them swimming
as fast as an Olympic sprinter can run.

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Today, they're hunting
within sight of Tinseltown.

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Working together,
they scour the ocean for prey.

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Soon, they round up
a giant school of anchovies.

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Other hunters spot the opportunity.

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Californian sea lions and diving seabirds.

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It looks like an easy meal.

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But the anchovies have a dazzling defense.

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They stay close
and coordinate their movements.

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The blur of twisting and turning fish
confuses the hunters.

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They can't pick out any single fish.

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This looks like a job for team dolphin.

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They drive a wedge into the shoal.

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Working together, they gradually break
the shoal up into smaller chunks.

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Now, it's easier to target
the individual fish.

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Every predator eats as much as it can...

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before the gatecrashers arrive.

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A humpback whale can eat 80,000 anchovies
in a single gulp.

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So, two whales together soon bring
an end to this Hollywood drama.

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Since humans were banned
from hunting whales,

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some have made a comeback here.

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Including the greatest of all.

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The blue whale.

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The biggest animal
that's ever lived.

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Up to 200 tons and 100 feet long.

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North America is one of the best places
in the world to see blue whales.

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Almost as many live here now
as there were before hunting began.

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The rich Pacific sustains
these ocean giants,

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and also giants of the land.

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Off Northern California,
fog banks form over the cool ocean.

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Breezes blow the fog inland...

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where coastal redwoods,
the tallest trees on Earth,

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absorb the fog water through their leaves.

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There are woodlands watered by the ocean
on our Atlantic Coast too.

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This is the only tropical forest
in the Lower 48.

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The South Florida home
to one of our smallest heroes.

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You're looking right at him.

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North America's tiniest toad.

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An oak toad, the size of a nickel.

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He's got to head out to eat.

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The problem is, when you're this small,

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pretty much everything else
wants to eat you.

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This little guy needs courage.

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For him, a 50-yard journey to find food
is a dangerous quest.

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With predators at every turn.

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In his path, the biggest toad in America.

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At over ten times his size,

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this cane toad could swallow him whole.

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Better hope
the big guy's not hungry.

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Oof. Lucky escape.

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It won't always be so easy, though.

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Some hunters here are hungry.

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A garter snake.

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She smells the air with her forked tongue
to track her prey.

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She's nearly on him.

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But she loses the trail.

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Maybe the toad used the smell of the snail
to mask his own scent.

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It pays to be small sometimes.

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Now, there's just one last predator
in the toad's path.

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Perhaps the most sinister of them all.

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A sundew, a carnivorous plant.

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It uses a sugary secretion
to lure in its prey.

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The ant is trapped
by the sticky droplets.

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Allowing the sundew to slowly engulf it.

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A deadly predator...

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but just what the toad's been looking for.

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He fires out his tongue
faster than the human eye can blink...

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stealing ants
from the sundew's sticky grip.

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Who doesn't love
an all-you-can-eat buffet?

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Brave and crafty,

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he's definitely a hero
of this lush coastal forest.

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Inland,
America is a drier world.

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In California, humid Pacific air
can't cross the High Sierras.

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Beyond is the driest place
in North America

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and the hottest place on Earth,
Death Valley.

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Named by European settlers

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who almost died
crossing this scorched plain.

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The western deserts are the setting

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for some of the most famous landscapes
on Earth.

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Some are the stuff of legend.

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In the stories of the Navajo,

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the 1,000-foot-tall towers
of Monument Valley...

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are the bodies of defeated monsters.

00:31:29.721 --> 00:31:33.099
The bare rock of these deserts
have been carved by the elements

00:31:33.182 --> 00:31:34.767
for thousands of years.

00:31:38.438 --> 00:31:40.189
With spectacular results.

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The Grand Canyon,
the largest canyon in America.

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Nearly 300 miles long...

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and over a mile deep.

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It's truly awe-inspiring.

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But how do you make a living here?

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Rule one. You gotta be tough.
Able to endure months of drought.

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Rule two. Everyone,
from this mountain lion

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all the way down the food chain,
has to grasp the opportunity

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when rain does make it
beyond the mountains.

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When it rains here...

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it rains here,
up to two inches an hour.

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After the storm,

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all the locals come out to drink.

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Even those,

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like this rattlesnake,
who usually stay hidden.

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For this roadrunner,

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the rain presents more than just a chance
to quench his thirst.

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He has his eye on a female.

00:33:42.812 --> 00:33:45.815
But despite his best efforts
at personal grooming,

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she's not interested.

00:33:55.408 --> 00:33:56.868
So, lucky for him,

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the rain has brought out
what he needs to impress his lady.

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Food.

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The perfect gift for a first date...

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a scorpion.

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No luck there.

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How about a juicy lizard?

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Surely, this will win her heart.

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I mean, who couldn't resist fresh lizard
delivered with a shake of the tail?

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She's leading him on a dance.

00:35:33.047 --> 00:35:34.173
She's interested.

00:35:36.759 --> 00:35:39.428
But there's trouble ahead.

00:35:41.264 --> 00:35:42.890
The rattler is still out.

00:36:04.203 --> 00:36:06.497
The shock puts her off romance.

00:36:10.585 --> 00:36:11.794
It's too bad.

00:36:13.379 --> 00:36:16.132
But no unwanted gift should go to waste.

00:36:22.471 --> 00:36:26.350
Especially in the desert,
where the good times

00:36:27.185 --> 00:36:28.644
usually don't last long.

00:36:32.690 --> 00:36:35.943
Out here, change can come fast.

00:36:42.491 --> 00:36:46.287
But for sheer scale of change,
head to the north of our continent.

00:36:56.297 --> 00:36:58.299
The White Mountains of New Hampshire.

00:36:59.800 --> 00:37:03.638
Scene of one of
the most famous transformations on Earth.

00:37:10.603 --> 00:37:15.483
As winter approaches,
the trees lose pigments from their leaves.

00:37:19.570 --> 00:37:22.031
The cue for a magical display.

00:37:26.160 --> 00:37:28.663
The fall colors of New England.

00:37:47.139 --> 00:37:49.976
The color change sweeps
through the plants

00:37:50.434 --> 00:37:52.645
and the animals.

00:37:55.022 --> 00:37:59.026
Some caterpillars here change color
with the leaves.

00:38:10.871 --> 00:38:14.417
It's a neat trick,
which means they can stay camouflaged

00:38:14.500 --> 00:38:16.585
while their home changes around them.

00:38:23.676 --> 00:38:28.139
The fall transformation is the beginning
of the great northern winter.

00:38:31.392 --> 00:38:33.936
Brutal... and beautiful.

00:38:41.986 --> 00:38:46.449
The northern lights dance
over the summit of Denali in Alaska,

00:38:48.075 --> 00:38:51.912
our highest mountain
and the coldest place on Earth

00:38:52.496 --> 00:38:53.914
outside of Antarctica.

00:39:01.547 --> 00:39:06.052
Through the long winter months,
the weak sun brings no warmth.

00:39:09.055 --> 00:39:12.266
So, you've got to be ready
to take advantage of the good times

00:39:12.892 --> 00:39:15.353
when spring finally comes.

00:39:26.280 --> 00:39:28.449
A caribou herd is on the move...

00:39:30.493 --> 00:39:33.120
seeking out the newly exposed grass.

00:39:35.706 --> 00:39:38.626
But this female has dropped
behind the herd...

00:39:41.212 --> 00:39:42.713
to have her calf.

00:39:46.384 --> 00:39:49.470
He's the last-born youngster
of this calving season.

00:39:51.389 --> 00:39:55.726
It's going to take a heroic effort
from Mom to keep him safe.

00:40:00.398 --> 00:40:03.943
At just an hour old,
she pushes him to get moving.

00:40:05.820 --> 00:40:07.613
They're vulnerable alone.

00:40:10.241 --> 00:40:14.036
Way ahead,
the herd offers safety in numbers.

00:40:26.966 --> 00:40:29.635
She's nearly caught up
with another mom and calf

00:40:29.927 --> 00:40:32.096
who are also trailing behind the herd.

00:40:35.558 --> 00:40:39.687
But her tiny, last-born calf
is struggling to keep pace.

00:40:45.526 --> 00:40:49.530
And the last place you want to be
is bringing up the rear.

00:40:52.741 --> 00:40:55.744
Grizzly bears are on the caribous' tail,

00:40:56.078 --> 00:41:00.291
recently emerged from hibernation
and very hungry.

00:41:21.729 --> 00:41:24.523
This bear is more desperate than most.

00:41:25.524 --> 00:41:29.153
She's a mother too,
with three young cubs in tow.

00:41:57.139 --> 00:42:01.435
The older calf
tries to keep safe by keeping still.

00:42:12.363 --> 00:42:13.656
But he panics.

00:42:21.830 --> 00:42:23.707
Mom calls to encourage him.

00:42:30.631 --> 00:42:32.633
But she's helpless against the bear.

00:42:44.019 --> 00:42:45.729
Some battles can't be won.

00:42:51.443 --> 00:42:54.697
This small meal won't sustain
the bears for long.

00:43:00.244 --> 00:43:03.539
The mom of the youngest calf
needs to keep him on the move.

00:43:13.007 --> 00:43:15.426
Soon, they catch up
with the rest of the herd.

00:43:23.517 --> 00:43:26.979
The caribou choose a dangerous route
to shake off the bears.

00:43:30.357 --> 00:43:36.614
Ahead of the herd is a river,
fast flowing and swollen with melted snow.

00:43:43.162 --> 00:43:48.167
It's tough for the adults.
For the calves, it can be deadly.

00:43:52.129 --> 00:43:58.010
They've only just learned to walk,
and now, it's sink or swim.

00:44:03.182 --> 00:44:06.435
The mother of the youngest calf
has brought him safely this far,

00:44:07.895 --> 00:44:09.730
but she can't help him with this.

00:44:16.028 --> 00:44:17.946
It's possible death in front...

00:44:19.823 --> 00:44:21.659
or certain death behind.

00:44:34.672 --> 00:44:39.176
Where she leads,
hopefully, he'll follow.

00:45:07.246 --> 00:45:08.706
He's struggling to swim.

00:45:46.285 --> 00:45:47.453
He's made it!

00:45:49.663 --> 00:45:52.332
The bear won't risk crossing
with her cubs.

00:45:58.547 --> 00:46:01.425
Mama caribou
has led her calf to safety.

00:46:05.721 --> 00:46:09.433
And just in time, he found his inner hero.

00:46:23.489 --> 00:46:27.367
It's ultimately the land itself
that shapes our heroes.

00:46:36.251 --> 00:46:40.130
Just look deeper
into every corner of this great continent,

00:46:42.216 --> 00:46:47.596
and you'll find beautiful landscapes,
graced by icons of the American wild.

00:46:50.224 --> 00:46:54.645
Heroes supremely adapted
to the challenges of their worlds.

00:47:02.027 --> 00:47:05.447
Striving to overcome
all that life throws at them...

00:47:10.536 --> 00:47:13.163
...and surviving
to raise new generations...

00:47:24.925 --> 00:47:29.096
...that can call
this beautiful land... home.

00:47:30.227 --> 00:47:35.983
Under these spacious skies