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[thunder rumbling]

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NARRATOR:
The story of life on Earth...

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[loud roar]

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has been marked by a series of
catastrophic extinction events.

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Natural disasters which have
threatened to wipe out

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many of the creatures
that call our planet home.

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But, after every brush with
death, life has come back

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even stronger.

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[peaceful music]

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NARRATOR: One such event took
place 305 million years ago,

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when huge swamp forests
dominated much of the earth.

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And were home to strange
new creatures.

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[loud growling]

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But the forests were
so astonishingly successful,

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they changed the planet,

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making Earth colder and drier.

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Unfortunately, this then
drove them to extinction.

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But life returned
more resilient and diverse...

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than ever.

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[theme song]

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[insects buzzing]

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[soft roar]

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NARRATOR:
Long before the dinosaurs

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the world is dominated
by plants.

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Lush, water-logged swamp
forests cover the land.

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And down among the roots,

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live countless strange
and wonderful creatures.

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A little amphibian
called Diplocaulus.

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This is a very special
night for her.

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It’s that time of year

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when she looks for a burrow
to lay her eggs.

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[Diplocaulus croaks]

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But this riverbank
is fully booked.

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Every mother is taking
advantage of the damp night

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to find their own nesting spot.

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[loud croaks]

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All the burrows are occupied.

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As morning dawns,

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she realizes she waited
too long to book a burrow.

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So, she makes her own.

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[bright music]

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The world she lives in is
a triumph of plant power.

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Herbivores have yet to evolve

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so the vegetation can grow
untouched by all but insects.

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Horsetails and tree ferns
stretch as far

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as the eye can see.

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Towering above are scale trees,
the giants of this forest,

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but they are nothing
like the trees we know today.

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Their trunks are rigid hollow
tubes that can grow as tall

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as a 14 story building
in less than 15 years.

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[crickets chirping]

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The extent of these forests
is staggering.

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For 50 million years

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plants have been the dominant
life force on land.

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As the continents have drifted
together vast lowland basins

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have formed along the equator

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and these have filled with
billions of swamp trees.

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These forests have released
so much oxygen,

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that they’ve supercharged
the Earth’s atmosphere.

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Oxygen levels are the highest
the planet has ever seen.

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This has boosted the animals.

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Some insects have grown
enormous,

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like the Griffinfly...

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with a wingspan
as big as a crow’s.

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[Griffinfly buzzing]

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But oxygen doesn’t just
fuel growth.

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But it also fuels fire.

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Even in this wet swamp,

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a single lightning strike
can set off a forest inferno.

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Our little Diplocaulus
will be safe here

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in a labyrinth
of drowned roots.

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But water isn’t
the natural habitat

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for many forest dwellers.

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Dendromaia.

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Her dry scaly skin shows
she is a reptile,

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one of the first vertebrates
to leave the water

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and live permanently on land.

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[wood cracking]

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So, for her,
the fire is a huge threat.

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In this oxygen rich atmosphere,

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one ember can quickly
become a raging blaze.

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[tense music]

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To save herself she needs
to run now but she has a nest

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full of babies nearby
and she won’t abandon them.

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[dramatic music]

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The fire is moving so fast
she only has seconds.

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[babies Dendromaiae chitters]

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She and her babies
are surrounded by chaos.

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[babies Dendromaiae chitters]

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[wood cracking]

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NARRATOR: 305 million years ago

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dense fast-growing forests
cover the equator.

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They are so successful they
have pushed up the amount of

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oxygen in the atmosphere
to record levels.

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But all this oxygen has
intensified forest fires

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so much so that even
waterlogged wood burns.

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The fire has cut this mother
off from her babies.

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[babies Dendromaiae chitters]

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[dramatic music]

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She is desperately trying to
reach them before the flames.

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She’s got them, but now she
needs to get them out of there.

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[wood cracking]

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[calming music]

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She’s done it.

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As the wind changes direction,

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it starts to drive
the fire away.

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Our heroic mother has saved
her babies from the flames.

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The next morning,

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it looks as though
the smoke is still lingering.

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But this isn’t smoke.

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It’s something very different.

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Spores, billions of them,

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So small they are almost
invisible to the naked eye.

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These tiny spores are

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how these extraordinary
scale trees begin life.

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They need just the right
conditions to germinate,

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and the damp soil here
is perfect.

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Our Diplocaulus mom
has been busy digging.

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And she’s made her own burrow
in the riverbank.

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Here, water from the swamp
has created a tiny pool.

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This is where
she has laid her eggs.

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Over the next few weeks this
mom will dedicate herself

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to protecting her brood
until they hatch.

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Because these swamps
are filled with predators.

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[predator growling]

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They can be heard calling
through the forest.

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[growling]

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The calls are coming from giant
amphibians called Eryops.

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They are carnivores and
can grow up to eight feet long.

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These beasts are among
the largest land animals

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on the planet and things are
about to get steamy.

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It’s time for their
annual courtship.

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[Eryops calling]

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Their calls are booming
through the forest

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for one purpose...

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to attract a female
and it’s worked.

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[soft growling]

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Let the serenading begin!

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[Eryops calling]

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Hardly a classic love
ballad but it’ll do.

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Now a couple of the males want
to show off different skills.

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One male starts a new contest.

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[Eryops deep calling]

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His low frequency rumbles
make the water...dance.

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Interesting.

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But the other guy
can do that too.

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[Eryops deep calling]

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She’s still not sure
who to choose.

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This could get ugly.

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NARRATOR: Over 300 million years
before humans evolve,

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the Earth’s equatorial regions
are cloaked

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in dense swamp forests dominated
by mosses and ferns.

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The animals here thrive in the
damp, oxygen-rich atmosphere.

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These Eryops are amphibians

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and among the largest creatures
on land.

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Each as big
a silverback gorilla,

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they are formidable predators

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with a mouthful
of curved fangs.

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But they are not here to hunt,

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they are here to win a mate.

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These two suitors are
sumo wrestling, swamp-style.

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Battling to impress
a potential mate.

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[Eryops cries]

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[growling]

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[loud growling]

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Finally, a champion.

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[Eryops calling]

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The winner will stay
firmly attached

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in a slippery embrace
for hours.

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When she finally lays
her eggs,

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he will be ready
to fertilize them.

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Then, both parents abandon them.

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Of the 500 eggs she lays,

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only about 10 will survive
to adulthood.

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Down in her burrow our
Diplocaulus mom

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is a much more caring parent.

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Two weeks on and she’s still
devotedly tending her eggs.

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But she can tell something’s
not right.

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When she laid her eggs
they were underwater,

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now some are exposed.

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The water level is dropping

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and the reason lies far
beyond her little burrow.

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305 million years ago,

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while the endless forests are
producing loads of oxygen,

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they are also absorbing
huge amounts of carbon dioxide,

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a greenhouse gas that keeps
the planet warm.

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As each tree falls,
and submerges into the swamp,

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it locks the carbon away
underground.

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For millions of years,

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these trees have been rotting
down on top of each other.

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Eventually, this one period
in Earth’s history

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will create 90 per cent
of all our coal.

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This also means carbon dioxide
levels in the atmosphere

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have been dropping

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and the whole planet
has started to cool.

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Several ice sheets
have begun to grow

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over the southern continents,

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and they are expanding towards
the equator.

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With cooler seas,
there is less evaporation,

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less water in the atmosphere,
and, therefore, a drier climate.

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This means dry seasons
are getting longer

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and droughts worse
in the swamp forest.

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The consequences
could be devastating

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for our caring mother.

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As the swamp drains,

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she tries everything to keep
her babies from drying out.

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00:18:32,152 --> 00:18:33,821
And she’s not the only one.

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00:18:36,740 --> 00:18:38,826
If this drought continues
much longer,

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00:18:38,867 --> 00:18:42,704
her baby-filled burrow
will become a tomb.

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00:18:46,374 --> 00:18:50,629
But a drier swamp is not a
problem for all creatures here.

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00:18:53,340 --> 00:18:56,218
Down under the ferns
a Dendromaia shows

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00:18:56,259 --> 00:19:00,848
how reptiles managed to escape
being so dependent on water.

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00:19:04,392 --> 00:19:06,895
They lay eggs with
waterproof shells.

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00:19:08,230 --> 00:19:09,899
So they can stay on land

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00:19:09,940 --> 00:19:12,651
without the fear of their eggs
drying out.

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00:19:13,610 --> 00:19:16,738
[crickets chirping]

217
00:19:22,494 --> 00:19:25,914
[soft instrumental music]

218
00:19:28,875 --> 00:19:33,422
As night falls moonlight picks
out the glowing wing cases

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00:19:33,463 --> 00:19:35,674
of a million insects.

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00:19:37,175 --> 00:19:41,263
The deep forests belong
to the creepy crawlies,

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00:19:43,848 --> 00:19:46,727
and the biggest of these
is perhaps

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00:19:46,768 --> 00:19:51,023
the most bizarre creature
in an already weird world.

223
00:19:58,613 --> 00:20:04,703
Arthropleura, a giant millipede,
eight feet long.

224
00:20:07,122 --> 00:20:08,457
Using her antenna,

225
00:20:08,498 --> 00:20:11,543
she probes
the forest floor for food...

226
00:20:14,796 --> 00:20:17,925
creeping closer and closer

227
00:20:17,966 --> 00:20:22,304
to our young mom’s burrow
full of babies.

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00:20:24,806 --> 00:20:26,391
[squeaking]

229
00:20:28,518 --> 00:20:33,399
[dramatic instrumental playing]

230
00:20:33,440 --> 00:20:35,317
[chirping]

231
00:20:45,160 --> 00:20:47,037
Deep in the swamp forest,

232
00:20:47,078 --> 00:20:51,292
a Diplocaulus mom has laid
her eggs in a flooded burrow

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00:20:51,333 --> 00:20:55,045
to protect them from
the many predators outside.

234
00:20:56,087 --> 00:21:00,384
Unfortunately, tonight,
the entrance has been discovered

235
00:21:00,425 --> 00:21:03,262
by an eight-foot-long
Arthropleura,

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00:21:03,303 --> 00:21:05,597
a monstrous millipede.

237
00:21:07,932 --> 00:21:13,856
[tense instrumental playing]

238
00:21:13,897 --> 00:21:15,607
[chirping]

239
00:21:25,283 --> 00:21:26,952
[chirping angrily]

240
00:21:27,869 --> 00:21:29,705
But this eight-foot monster

241
00:21:29,746 --> 00:21:32,916
hasn’t met our fiercely
protective mother.

242
00:21:38,046 --> 00:21:41,508
In fact,
she is no threat at all.

243
00:21:45,178 --> 00:21:47,139
She’s a gentle giant.

244
00:21:48,807 --> 00:21:53,854
[wondrous instrumental playing]

245
00:22:00,235 --> 00:22:05,198
Soon, she finds the food
she was looking for all along...

246
00:22:07,075 --> 00:22:09,578
something rich in nutrients.

247
00:22:12,747 --> 00:22:14,624
Eryops droppings.

248
00:22:18,503 --> 00:22:25,135
[expansive instrumental playing]

249
00:22:26,010 --> 00:22:28,513
The drought is intensifying.

250
00:22:33,226 --> 00:22:36,105
The drier soil
no longer holds enough water

251
00:22:36,146 --> 00:22:38,899
to sustain
the giant scale trees.

252
00:22:41,151 --> 00:22:43,236
[loud crash]

253
00:22:44,237 --> 00:22:46,115
The swamp is
no longer wet enough

254
00:22:46,156 --> 00:22:48,450
for the spores
to germinate,

255
00:22:48,491 --> 00:22:50,869
and the trees cannot recover.

256
00:22:52,495 --> 00:22:57,209
The once endless groves
are becoming patchy and sparse.

257
00:22:59,794 --> 00:23:02,506
[chirping quietly]

258
00:23:08,511 --> 00:23:10,139
Against all the odds,

259
00:23:10,180 --> 00:23:13,225
our Diplocaulus mom has managed
to keep enough water

260
00:23:13,266 --> 00:23:16,561
in her burrow for her
eggs to survive.

261
00:23:17,353 --> 00:23:21,817
[sweeping instrumental playing]

262
00:23:27,614 --> 00:23:30,992
And now,
they’re starting to hatch.

263
00:23:31,367 --> 00:23:33,870
A miracle of new life.

264
00:23:35,288 --> 00:23:36,999
But unlike their mother,

265
00:23:37,040 --> 00:23:39,626
they can only breathe
underwater.

266
00:23:40,543 --> 00:23:42,963
For now,
they have feathery gills

267
00:23:43,004 --> 00:23:45,298
that absorb all
the oxygen they need.

268
00:23:47,008 --> 00:23:49,970
It will be eight weeks
before their lungs develop

269
00:23:50,011 --> 00:23:52,097
and they can breathe on land.

270
00:23:54,724 --> 00:23:56,310
Despite all her hard work,

271
00:23:56,351 --> 00:23:59,104
their birthing pool
is shrinking.

272
00:24:02,690 --> 00:24:05,318
Our mom is running out of time,

273
00:24:05,902 --> 00:24:10,699
and digging around on this bank
just got riskier.

274
00:24:16,663 --> 00:24:20,792
Forced by the drought to hunt
in these shallow waters...

275
00:24:21,751 --> 00:24:25,714
Orthacanthus,
a freshwater shark.

276
00:24:29,717 --> 00:24:31,678
Aquatic animals here
are now pushed

277
00:24:31,719 --> 00:24:34,097
into smaller
and smaller pockets.

278
00:24:35,557 --> 00:24:39,769
Global cooling has brought
the forests to a tipping point.

279
00:24:42,939 --> 00:24:46,735
These baby Eryops,
abandoned by their parents,

280
00:24:46,776 --> 00:24:48,612
are now stuck.

281
00:24:50,446 --> 00:24:54,743
Thousands of them,
with no space and no food.

282
00:24:59,747 --> 00:25:03,168
It’s not long before
they turn on each other.

283
00:25:06,796 --> 00:25:13,345
[sorrowful instrumental playing]

284
00:25:22,687 --> 00:25:28,235
Just one tiny tragedy in
a world that is falling apart.

285
00:25:34,198 --> 00:25:36,243
In her underground nursery,

286
00:25:36,284 --> 00:25:39,913
our Diplocaulus mom
is also desperate.

287
00:25:49,505 --> 00:25:51,550
To save her remaining babies,

288
00:25:51,591 --> 00:25:55,345
she carries them in her mouth
down to the stream.

289
00:26:36,469 --> 00:26:40,557
She has spent weeks fiercely
defending these little ones.

290
00:26:41,182 --> 00:26:44,269
Now, there’s
nothing more she can do.

291
00:26:45,144 --> 00:26:47,063
They are on their own.

292
00:26:48,898 --> 00:26:52,402
But they’re not
the ones in danger.

293
00:26:55,697 --> 00:26:59,743
[menacing instrumental playing]

294
00:27:12,588 --> 00:27:15,676
NARRATOR: After an unnaturally
long dry season,

295
00:27:15,717 --> 00:27:18,053
the swamp forest is suffering.

296
00:27:20,638 --> 00:27:24,142
Our Diplocaulus mom
has had to abandon her burrow

297
00:27:24,183 --> 00:27:25,935
to save her babies.

298
00:27:27,770 --> 00:27:29,398
Holding them in her mouth,

299
00:27:29,439 --> 00:27:31,816
she has carried
them down to the river.

300
00:27:33,401 --> 00:27:37,405
She has no idea
she’s being stalked.

301
00:27:38,197 --> 00:27:41,868
[tense instrumental playing]

302
00:27:52,170 --> 00:27:56,883
[fraught instrumental playing]

303
00:28:17,236 --> 00:28:20,407
The starving shark
has overreached.

304
00:28:26,496 --> 00:28:28,331
His last mistake.

305
00:28:33,127 --> 00:28:35,422
[chirping quietly]

306
00:28:38,090 --> 00:28:40,844
Our mom returns
to her empty burrow.

307
00:28:41,803 --> 00:28:46,516
Her best hope now is to wait
out the dry season underground.

308
00:28:53,856 --> 00:29:01,239
[poignant instrumental playing]

309
00:29:08,037 --> 00:29:09,414
The swampland forests

310
00:29:09,455 --> 00:29:12,250
are the architects of
their own destruction.

311
00:29:14,836 --> 00:29:18,715
By absorbing so much carbon
dioxide from the atmosphere,

312
00:29:18,756 --> 00:29:22,385
they set in motion
unstoppable global cooling.

313
00:29:22,969 --> 00:29:26,264
And a cooler world
is a drier world.

314
00:29:32,687 --> 00:29:35,065
Inside her burrow,
our Diplocaulus

315
00:29:35,106 --> 00:29:38,193
has made herself
a mucus cocoon to hibernate.

316
00:29:40,194 --> 00:29:42,155
But her time has passed.

317
00:29:42,196 --> 00:29:44,949
She will raise
no more babies in this forest.

318
00:29:45,741 --> 00:29:50,371
Outside, the age of plants
is coming to an end.

319
00:29:55,376 --> 00:29:57,712
Millions of years pass.

320
00:29:58,796 --> 00:30:00,465
From the west to the east,

321
00:30:00,506 --> 00:30:05,094
nearly 90% of
swamp forest trees are lost.

322
00:30:06,637 --> 00:30:07,889
And along with them,

323
00:30:07,930 --> 00:30:10,976
many of the strange
and wonderful creatures

324
00:30:11,017 --> 00:30:12,811
that depended on them.

325
00:30:13,978 --> 00:30:19,275
Eventually, the earth warms
and the ice starts to melt.

326
00:30:21,986 --> 00:30:25,406
But the land remains
a drier place.

327
00:30:26,157 --> 00:30:31,329
[sweeping instrumental playing]

328
00:30:41,005 --> 00:30:42,841
Instead of scale trees,

329
00:30:42,882 --> 00:30:46,010
other trees
now dominate the landscape.

330
00:30:48,471 --> 00:30:49,722
Conifers.

331
00:30:59,231 --> 00:31:01,234
Their crucial advantage

332
00:31:01,275 --> 00:31:04,654
is that instead of
using spores to reproduce,

333
00:31:04,695 --> 00:31:06,281
they use seeds.

334
00:31:09,408 --> 00:31:14,038
These simple packets of food
give seedlings a head start.

335
00:31:18,459 --> 00:31:23,757
[dramatic instrumental playing]

336
00:31:23,798 --> 00:31:26,092
The animals
that live in and around

337
00:31:26,133 --> 00:31:29,304
these conifer forests
have evolved...

338
00:31:32,390 --> 00:31:35,810
and become much, much bigger.

339
00:31:37,728 --> 00:31:40,523
[growling]

340
00:31:41,607 --> 00:31:46,821
[dramatic instrumental playing]

341
00:32:01,252 --> 00:32:04,422
This is a Dimetrodon.

342
00:32:08,801 --> 00:32:11,054
As long as a dump truck,

343
00:32:11,095 --> 00:32:14,432
she is the apex predator
in these forests.

344
00:32:15,599 --> 00:32:18,311
And she smells something
in the ground.

345
00:32:32,742 --> 00:32:34,285
An amphibian.

346
00:32:35,119 --> 00:32:36,663
Even in this new world,

347
00:32:36,704 --> 00:32:39,541
amphibians can survive
drier periods

348
00:32:39,582 --> 00:32:41,584
by hibernating underground.

349
00:32:45,921 --> 00:32:49,259
Unless a giant reptile with
a good sense of smell

350
00:32:49,300 --> 00:32:51,135
finds them first.

351
00:32:54,472 --> 00:32:57,517
[distant bellowing]

352
00:32:57,558 --> 00:33:02,605
A curious call reaches the
Dimetrodon like a dinner bell.

353
00:33:03,230 --> 00:33:07,193
[bellowing continues]

354
00:33:19,038 --> 00:33:20,790
Cotylorhynchus.

355
00:33:22,792 --> 00:33:25,670
A cumbersome,
plant-eating machine.

356
00:33:28,631 --> 00:33:31,342
His ancestors were carnivores,

357
00:33:31,383 --> 00:33:33,636
but his species has evolved
to become one of

358
00:33:33,677 --> 00:33:36,264
the first large herbivores.

359
00:33:38,474 --> 00:33:40,477
In the time of
the swamp forests,

360
00:33:40,518 --> 00:33:43,938
the only creatures
that ate plants were insects.

361
00:33:45,439 --> 00:33:48,026
But plants aren’t
as nutritious as meat,

362
00:33:48,067 --> 00:33:53,239
so he needs a massive gut
to break down his tough diet.

363
00:34:02,289 --> 00:34:05,376
Today, though,
something is wrong.

364
00:34:09,088 --> 00:34:10,548
Dizziness.

365
00:34:12,216 --> 00:34:13,718
Drooling.

366
00:34:15,177 --> 00:34:16,846
-Gas.
-[flatulence]

367
00:34:17,721 --> 00:34:20,767
All the signs of poisoning.

368
00:34:22,768 --> 00:34:25,271
The moment animals
started eating plants,

369
00:34:25,312 --> 00:34:29,108
plants started producing toxins
to put the herbivores off.

370
00:34:30,234 --> 00:34:34,739
And today, he swallowed
the wrong kind of leaves.

371
00:34:37,199 --> 00:34:38,785
Another symptom?

372
00:34:40,369 --> 00:34:41,579
Collapse.

373
00:34:41,620 --> 00:34:43,706
[quiet flatulence]

374
00:34:44,582 --> 00:34:46,751
He’ll have to sleep it off.

375
00:34:48,085 --> 00:34:50,379
But this could be fatal.

376
00:34:51,714 --> 00:34:57,011
Nearby,
hungry eyes are watching.

377
00:34:58,095 --> 00:35:02,934
[growling]

378
00:35:07,438 --> 00:35:08,940
NARRATOR: It is 20 million years

379
00:35:08,981 --> 00:35:11,568
since the collapse of
the swamp forests.

380
00:35:11,609 --> 00:35:14,487
Conifers now cover the land.

381
00:35:20,075 --> 00:35:24,122
Beneath their branches,
reptiles have thrived,

382
00:35:24,163 --> 00:35:26,332
and some have grown enormous.

383
00:35:26,373 --> 00:35:29,919
[distant bellowing]

384
00:35:33,297 --> 00:35:37,427
This giant herbivore has eaten
some poisonous plants

385
00:35:37,468 --> 00:35:39,345
and decided to sleep it off.

386
00:35:39,762 --> 00:35:42,056
But this
has left him vulnerable,

387
00:35:42,097 --> 00:35:44,350
and he has attracted
the attention

388
00:35:44,391 --> 00:35:46,853
of a predatory Dimetrodon.

389
00:36:01,533 --> 00:36:03,703
[Dimetrodon exhaling]

390
00:36:06,121 --> 00:36:08,040
[growling]

391
00:36:14,797 --> 00:36:18,050
[hissing]

392
00:36:21,095 --> 00:36:22,722
[hissing]

393
00:36:25,599 --> 00:36:28,144
[distant growling]

394
00:36:30,562 --> 00:36:33,065
Luckily, he has friends.

395
00:36:39,071 --> 00:36:41,157
Big friends.

396
00:36:41,949 --> 00:36:48,373
[dramatic instrumental playing]

397
00:36:48,414 --> 00:36:51,542
[growling]

398
00:36:51,583 --> 00:36:56,714
[hissing]

399
00:37:04,096 --> 00:37:07,934
The Cotylorhynchus
is part of a herd,

400
00:37:07,975 --> 00:37:10,270
a new social grouping
herbivores use

401
00:37:10,311 --> 00:37:11,938
to defend themselves.

402
00:37:17,526 --> 00:37:19,153
Some other time.

403
00:37:24,074 --> 00:37:25,910
The collapse of
the swamp forests

404
00:37:25,951 --> 00:37:28,621
ushered in
a new era on land.

405
00:37:30,831 --> 00:37:33,918
It is the dawn of
the age of reptiles.

406
00:37:34,835 --> 00:37:38,089
And there are more
and more large herbivores

407
00:37:38,130 --> 00:37:40,633
who are starting
to break up the forests.

408
00:37:41,050 --> 00:37:44,178
And their dung
helps fertilize the ground.

409
00:37:47,806 --> 00:37:49,934
For the first time,

410
00:37:49,975 --> 00:37:53,813
animals are beginning
to shape their habitats

411
00:37:53,854 --> 00:37:55,982
on a massive scale.

412
00:37:59,651 --> 00:38:02,154
It’s the way of the future.

413
00:38:03,655 --> 00:38:09,829
[sweeping instrumental playing]

414
00:38:13,874 --> 00:38:19,672
[soft instrumental playing]

415
00:38:19,713 --> 00:38:22,800
NARRATOR: Today,
rainforests once again

416
00:38:22,841 --> 00:38:25,177
dominate the Earth’s
tropical regions.

417
00:38:31,392 --> 00:38:33,102
They have evolved to be

418
00:38:33,143 --> 00:38:36,022
the most diverse
environments on Earth.

419
00:38:38,399 --> 00:38:43,070
Home to half of all our plant
and animal species.

420
00:38:44,696 --> 00:38:48,743
It’s only recently they have
come under threat from humans.

421
00:38:54,915 --> 00:38:57,377
The rate at which
they are now shrinking

422
00:38:57,418 --> 00:39:00,713
is greater than any time
in Earth’s history.

423
00:39:10,889 --> 00:39:13,768
Could our impact cause
a tipping point,

424
00:39:13,809 --> 00:39:16,062
like the ancient swamp forests,

425
00:39:16,103 --> 00:39:18,856
that brings about
a complete collapse?

426
00:39:27,072 --> 00:39:31,619
Hope for the rainforests lies in
their incredible biodiversity.

427
00:39:33,287 --> 00:39:37,249
No one part of the forest
is quite like another.

428
00:39:39,793 --> 00:39:41,546
Along with this diversity

429
00:39:41,587 --> 00:39:44,840
comes a powerful ability
to regenerate.

430
00:39:47,426 --> 00:39:52,348
Where humans abandon land,
the forest recovers.

431
00:39:56,185 --> 00:39:59,272
Two-thirds of
today’s global rainforests

432
00:39:59,313 --> 00:40:01,232
are secondary regrowth.

433
00:40:02,357 --> 00:40:05,820
Bouncing back
after human impact.

434
00:40:16,038 --> 00:40:18,082
Modern tropical rainforests

435
00:40:18,123 --> 00:40:21,293
have proven themselves
to be remarkably resilient.

436
00:40:30,469 --> 00:40:34,765
Humans just need
to give them space to recover.

437
00:40:38,101 --> 00:40:42,607
♪ I see trees of green ♪

438
00:40:42,648 --> 00:40:45,401
♪ Red roses too ♪

439
00:40:45,442 --> 00:40:50,907
♪ I watch them bloom
for me and you ♪

440
00:40:50,948 --> 00:40:55,161
♪ And I think to myself ♪

441
00:40:55,202 --> 00:41:02,043
♪ What a wonderful world ♪

442
00:41:02,084 --> 00:41:07,298
♪ Yes, I think to myself ♪

443
00:41:07,339 --> 00:41:11,677
♪ What a wonderful world ♪