Why The Earth is So Special
The answers are hidden deep in the earth
birth,
To see the first human walk on earth, face
killer dinosaurs, dive into oceans full of bizarre life-forms, feel the bitter
chill of global ice ages and experience the fury of cosmic missile attacks, we
must travel back time until we reach the birth of the earth itself then we can
piece together our planets incredible story and discover why all of us are
here.
Our journey starts almost 5 billion years
ago, but this can’t be right.
There’s no sign of our beautiful blue
planet. Just a new born star, our sun, surrounded by all its dust.
We have arrived too early before the
earth has formed. Speeding up time and we can see gravity pull the dust into
tiny rocks. It hardly seems possible but something as complex as a planet is
made from nothing but dust.
Over millions of years gravity pulls
these rocks together to form the earth, one of at least 100 planets circling
the sun.
4.54 billion years ago,
our planet more like hell than home. Up
close the temperature is over 1200 degree celcius. There is no air just CO2,N2
and water vapor. It is so hot, so toxic that if we get closer we would get
suffocated in seconds. The new born planet is a boiling ball of liquid rocks.
There’s no solid surfaces, just endless lava.
A young planet called Theia is heading
straight to us. It’s size of mars and travelling 15 Km/Sec, 20 times faster than
a bullet. The intruder’s gravity distorted the earth’s surface. The blast wave
races out around the planet. It’s as though both planets turn to liquid.
Trillions of dusts blast out into space.
But over the course of just a thousand years, gravity works its magic and turns
the rubble into a ring of red-hot dots. Now, from the rings of ball, over 3000
km wide, our moon was born. It born just 22,000 km away instead of 4,00,000 km.
The sun rises over a cooling earth and
sets just 3 hours after rises. The impact has set the earth spinning so fast
that an entire day lasts just six hours, the days may pass quickly but the
earth changes slowly. To understand the making of our planet, we need to move
fast forward.
3.9 billion years ago, a hail of meteors,
we were under attack from debris left over from the solar system formation.
Meteors were holding miner droplets of waters. It seems these deadly missiles
could contain the vital ingredient for life in earth.
There was only a small amount of water
inside a meteors but as they bombard the earth for over 20 million years, pools
of water grown. The water collects on solid ground. The earth’s core remain hot
but its surface is cooled around 70 to 80 degrees , just enough to form a
crust.
In future, we could swallow this water. When
we take a drink of every sip, every puddle , every drop water in every ocean,
is billions of years old and it may have travelled millions of km inside
meteors to reach us.
The earth is more familiar now but still it
is a dangerous place. This wind is fast perhaps faster than the most
destructive hurricane.
The moon was so close to earth that its
gravity was overwhelming. It was createing huge tide that race the planet’s
surface.
But over time, the moon moves away, the waves
calm and the planet spins slow.
700 million years after the planet birth,
live giving water covers its surface.
But not just water, there’s something
else down there, tiny islands. They seems to have appeared from nowhere until
molten rocks bursts through the earths crusts and rises up through the oceans.
Over time the lava cools and formed a
volcanic island, this is how island formed. In the future they will join
together to form the first continents.
The infant earth has water and land. It
beginning to look like a planet we call home. But the atmosphere was toxic and
the temperature is scorching. Nothing could live here.
Meteors, they have been raining down
since the earth’s formation, but now 3.8 billion years ago the assault has entered
a violent new phase.
Something has disturbed the orbits of
these meteorites. They have already brought water to the planet but they are
carrying something else too. As the meteorites dissolve, they release their
minerals and transport carbon and primitive proteins, Amino Acids from outer
space to the bottom of the oceans.
Its dark, the sun rays can’t reach beyond
300 meters and it’s close to freezing. This must be a mirage, a city of
underwater cymenes. Sea water has seeped down into the earth through cracks in
the crust, getting hotter collecting minerals and gases on the way.
It’s this potent mixture that’s spewing
back out into the ocean. Those minerals and chemicals from the meteorites and
the water has become a chemical soup.
It’s impossible to know how and when, but
somehow these chemicals has come together to form life. The water is now full
of microscopic organism. These single-celled bacteria are the earliest form of
life on earth. This is a defining moment in the making of the planet.
Microscopic life is under way. To find more
complex life we need to travel forward through time to 3.5 billion years ago
and a shallow ocean.
Bacteria were standing together and it
was more like a growing mountain, called Stromatolite.
As if by magic these bacteria turns sun
light and CO2 into food. This process is called Photosynthesis. The food is
nothing but Glucose, a simple form of sugar, similar to the stuff we put in our
coffee and these magical transformation release a byproduct, a gas called
Oxygen.
Underwater the Stromatolite slowly fills
the oceans with Oxygen. The oxygen turns traces of iron in the water into rust.
This falls to the ocean floor to form deposits of iron rich rocks. One day we
will use these minerals to build bridges, ships and skyscrapers.
Above the waves, the oxygen transformed
the atmosphere. These Stromatolites were creating the single most important element
for life on earth. Without them, virtually every living beings would not exist.
When we take our next breath, we are doing it thanks to these colonies of ancient
bacteria.
Over the next 2 billion years, oxygen
level continues to rise and as the planet spins slows, the days get longer. Now
they lost at least 16 hours. We are discovering it takes a long time to make a
planet.
1.5 billion years ago, 3 billion years after
the planets birth and there’s no complex life.
No plants, no dinosaurs, no humans but
the earth has something that no other planet has, a force with the power to
change everything.
Our planet, a beautiful blue ball, dotted
with volcanic island, one and a half billion years ago, it was home to
primitive lives.
Over millions of years, we can see
something is rearranging the islands. Hidden beneath the ocean, the earth’s
crust has broken into vast plates. Deeper, still the earth’s core is at work. It’s
hotter than the surface of the sun. It is so hot it generates movement in the
rock beneath the crust. These movements push and pull the planets around the
globe and carry the oceans and the island with them. Millions of years raced by
seeing it like this our planet seems active, changing alive.
Over 400 million years, a vast new
supercontinent takes shape, called Rodinia.
In the shallow waters around Rodinia, Stromatolites
have been working their magic for over two billion years, pumping oxygen into
the atmosphere, the temperature is 30 degree Celsius and the day is 18 hour
long.
But this looks more like Mars than Earth.
To find life here we need to move on through time.
750 million of years ago,
The intense geological activity has
spawned a mass of volcanoes. This pumped CO2 into the atmosphere. Smoke and gas
everywhere. All that CO2 mixes with water to make acid rain. The rocks absorbed
the acid rain including CO2.
There is a lot of rocks on the earth
right now exposed when the continent tore apart. So many that vast quantities
of CO2 was absorbed out of the atmosphere and locked up in the earth’s rocks.
There’s not enough CO2 in the atmosphere to trap the suns heat around the planet.
In just a few thousand years, the temperature plants to around minus -50
degrees.
It’s the start of what some scientists
call snowball earth, a period they believed to be the longest coldest ice age
ever to grip the planet.
A vast wall of ice, thousands of meters
high, the ice was unstoppable. The more ice there is the more sunlight it
reflects away from the planet and the faster the ice spreads. There was a
second ice sheet just as high. The two sheets spread away from the poles
towards each other to meet at the equator. An ice sheet up to three Kilometers
thick and tunes the entire planet.
First the planet was a molten ball of
fire, now it’s a frozen ball of ice.
Virtually all the suns light and warmth
reflects back into space. But it can’t last forever. Something must release the
earth from this frozen prison and when it does who knows whether life will have
survived beneath the ice.
The surface was frozen but the core was
still hotter than the sun’s surface. Volcanoes have been erupting since the
world began to freeze but up until now even their heat and power make no impact
on the ice.
Volcanoes pumped out billions of tons of
CO2. Before the big freeze, the earth’s rocks absorb most of the CO2. But now
with the rocks smothered in ice, there’s nothing to absorb the gas, so it fills
the atmosphere.
Like a blanket it traps the suns warmth around
the planet. Temperature rise until now, after 15 million years, the ice begins
to melt. It’s thought that during snowball earth the ice pushed the crust down,
now as it melts the crust bounces op. this creates fissures and weak spots and
more and more volcanoes. These volcanoes release more CO2 and pushed the
temperature even higher. The melt gathers momentum. Oxygen level rockets.
Through a series of chemical reaction,
the ice has created oxygen. While the planet was frozen, the sun’s ultraviolet
rays reacted with the water molecules in the ice to produce a chemical rich in
oxygen, Hydrogen Peroxide. Now as the ice melts, the Hydrogen peroxide breaks
down and release massive amount of Oxygen.
The earth is waking up and it’s a very
different place.
Now 600 million years ago, the atmosphere
was warmer and it felt like summer day and the days were about 22 hours long.
Add all this water and it’s the perfect
recipe for life. Before snowball earth, primitive bacteria had emerged in the
ocean but surely they couldn’t have survived an ice age, 75 times longer than
the entire span of human history. If something has survived then our best
chance of finding it is where we last saw life, in the ocean.
Now 540 million years ago in an ocean
full of oxygen those primitive bacteria has evolved. A handful must have clones
for the big freeze.
There were plants everywhere and
something else. It looks like some kind of armored snug. It’s called Wewak SIA.
It’s one of the new generation of complex multi-celled organisms.
We’re entering one of the most dynamic
periods in the earth’s story, the Cambrian explosion.
Increased oxygen level allow creatures to
grow larger and develop bony skeletons, there are worms, sponges and trilobite.
Life in the oceans is blossoming. From microscopic
bacteria to a sea monster like Anomalocaris. It’s about 60cm long. All
Anomalocaris has to do is take its break.
There were Pecaya just 5 or so centimeter
long but they have got what may be the first ever spine. Over millions of
years, this simple structure will evolve into spine that keeps us standing
erect.
Beneath the waves there were already tens
of thousands of plant and animal species. The advance of life seems unstoppable.
460 million years ago, the plates had
moved again, below lies a new continent, Gondwana.
Oxygen level are close to those which we
live. The land should be covered with plants, crawling with creatures. But there
was not much there, just a few algae.
There’s only one explanation, the sun. It
blasts the surface with deadly radiation. The complex life we have seen in the
ocean doesn’t stand a chance on land. But 50 kilometers, on the earth’s
atmosphere something strange was happening.
When oxygen meets the suns radiation, the
oxygen turns into another type of gas called, ozone. This has forms a blanket
around the planet. These ozone layers absorbs the suns radiation.
Over 150 million years the ozone layers
gets thicker and stops more and more suns radiation from reaching the earth’s
surface. Without this layer, lives on land, simply don’t exist.
Now shielded from radiation, life
blossoms. Those small mossy lumps are the first land plants and they are
pumping out even more oxygen.
Until 360 million years ago they make the land their home.
From a creature like this that all four-legged vertebrate will evolve.
Dinosaurs, birds, mammals and eventually you and me. We have come a long way, from
burning to a dust to a blue-green planet, bursting with life.
There are still no human but there are fish, plants and
eagle sized dragonfly. This giant is called Meganula. What were once legs have
evolved into wings extending the dragonflies hunting territory over a vast
area. There are millipedes, spider all sorts of bugs down there.
A creatures called arthropods were among the very first to
set foot on land. They have already been around for hundreds of millions of years.
They look almost identical to the bugs that invade our homes today, except from
one big difference like Mega Nura, they are monsters.
We have stumbled into a lost world of giants were millipedes
are two meters long and scorpions are the size of wolves. All the oxygen in the atmosphere allows their
respiratory systems to be more efficient and frees up space for their body to
grow up.
A lizard-like creature called Anomus, the creatures we’ve
seen so far laid their eggs in water but its eggs contain all the water and
nutrients the developing hile Anomus needs.
The babies are growing in their own self-contained pond.
The egg is a major evolution in breakthrough. Now
animals can leave the water behind and conquer the land. Anomus is the new kind
of creature that will lead the advance, a reptile. Inevitably with life comes
death there’s so much dead plant matter it builds up and decease into dense
soggy layers.
Over hundreds of millions of years, rocks will cover these
layers. Heat from the earth’s core and pressure from the overlying rocks will
transform the layers of dead plants into seams of coal. Each lump of coal we
burn today to warm our homes and fire our power-stations is made of flowers and
trees that died 300 million years ago. Amidst the decay hidden from sight life
is starting soon. Seeds will germinate plants will grow and this wasteland will
live again. Life seems have conquer the planet.
250 million years ago, a herd of creatures graze the Siberian
plants are not dinosaurs, they are the lizards, the small reptile. This creatures
are Scooter Soars, the distant relatives of turtles. They are plant eaters and
if the plant eaters look this tough the carnivores must be seriously mean
something bigger. Gorgonops, a perfectly engineered prehistoric killing machine. It hunts Scooter-Soars and other reptiles.
Earht’s shaking. There’s lava but this isn’t one single
volcano, the entire land scape is erupting. It’s a flood basalt eruption, a
massive plume of mantle is rising up from the deep inside the earth pushing
molten rocks out through fissures in the Earth’s crust. The lush paradise is
now a lifeless hell. The Scooter-Soars and the Gorgonopsids a debt, the
greatest mass extinction the world has ever seen, the Permian Extinction.
On the other side of the continent of Gondwana it’s as if
nothing happened. Snowfall when the temperature is about 20 degree Celsius?
No it is not a snowfall, its ash fallout from the eruption
some 16,000 kilometres away. The ash
burns, suffocates and kills animals around the world. The atmosphere is full of
Sulphur dioxide from the eruptions. As it rains the gas turns into Sulphuric
acid and burns everything it falls on.
At first it seems like a local disaster but now it’s gone
global. The Siberian eruption increase the Earth’s carbon dioxide levels. The atmosphere
gets hotter and the water evaporates. The vegetation dies.
We saw what life had finally found a foothold. Now it looks
like we were wrong. There are no sign of lives in the land. Even the oceans become
empty too. Oceans water turns pink. The plants, trilobite, and predators
everything’s gone except the pink algae.
The new hotter atmosphere must have heated the oceans and
stripped them of oxygen. Now nothing except algae can survive in the stagnant
water.
The Siberian eruptions are transforming the entire planet. Nothing,
not even the deepest ocean floor is beyond their reach. Gas bubbles are coming
from the bottom of the ocean. But they are not oxygen, they are methane, a greenhouse
gas and at least 20 times deadlier then carbon dioxide. It’s escaping from the
vast pocket of methane gas beneath the seabed.
Until now the gas has been frozen but as the sea temperature rises, the gas
begins to melt.
Release into the atmosphere, this powerful gas pushes up temperature
even further. Up to 40 degrees, 6 degrees hotter than before the Siberian
eruption. Now even the creatures that have made it this far are doomed.
Its 500,000 years since the eruption first begin and all
this time for half a million years the lava has been pouring out. By now it
covers an area, the size of United States with a layer of molten rocks nearly
six kilometres deep.
250 million years ago, we’re back where we started, on a
lifeless planet almost.
Its 50 million years since virtually all life on earth was
wiped out and the planets has been transformed.
its now 200 million years ago and there’s just one super
continent called Pangea, stretching from pole to pole.
After the trauma of mass extinction, the planet is healing,
temperatures are stabilizing, the acid rain is neutralizing and vegetation’s
returning. With 95% of all life on earth wiped out, the field is open to new
species to emerge.
One that will dominate the planet like no other before or since,
the dinosaurs. All dinosaurs are evolved from the handful of reptiles that have
survived the Permain Extinction.
At four and half meters tall, their size make them slow and
vulnerable. A tyrannosaurus, they are
small and fast.
Ama Saurus is too big a meal for one tyrannosaurus but not
for two.
The dinosaurs have repopulated the earth but no species contain
this restless volatile planet.
The earth’s crust is thinning here. Lava shaking with
earthquakes as though it’s being stretched by some unseen force and the same
thing is happening all the way down what will be North America’s eastern seaboard.
The earth’s plates are on the move again.
190 million years ago, the great super continent of Pangea breaks
out.
A vast slab of land has broken away you creates a chasm and
this fills with a new ocean called the Texas over what will one day be the
middle east. Currents are pushing nutrients up into the coastal waters running
along what will be Saudi Arabia, Iraq and Iran. The nutrients attract fish in
their millions and with so much of life also comes death. Dead fish and plankton
carpet the ocean floor.
Over the 10 million years, layers of rock will bury and heat
the dead creatures. Ancient fish and plankton will become oil. Every litre of
oil in our cars, every piece of plastic on the planet, the paint in our walls,
the carpet under our feet, even the soap you was with, almost all originated in
this way.
The chasm between the two continents fills to create a vast
ocean, the Atlantic. They are in the middle of volcano. We’ve seen plates move
before. We know it’s caused by currents
deep beneath the earth’s crust. This process is happening down there, right
now.
The entire seafloor has been torn in two and pushed up into
a ridge of mountain and volcanoes. It’s growing higher than the Himalayas and
longer than the Rockies.
The water’s hot here. Molten lava is forcing its way out
from deep inside the earth. As the lava cools, it’s creating a new range of
volcanic mountains and new ocean floor. This is what’s pushing the plates and
Pangea apart and rearranging the world.
It’s this geological activity that makes the earth restless,
creating unique and every time the planet reinvents itself the things that live
on it must adapt and evolve.
Things like this, the Ichthyosaurs, their reptile ancestors lived
on land but as the planet changed, so did they. They grew fins and moved into
the newly formed Atlantic Ocean. They are six meters long and fast. It travels
at about forty kilometres an hour. It’s the oceans fastest creature, the most
efficient predator and it’s ruled the earth’s oceans for 50 million years.
But now there is a new contender for the crown, Plesiosaurs,
longer than a bus and heavy as a truck. Its jaws are immense over eight times
more powerful than a great white shark and its teeth are 30 centimetres long.
The earth and the creatures that live on it has changed
beyond recognition.
The dinosaur’s world maybe different but they’re as dominant
as ever. They appear invincible.
65 million years ago, it’s a shrew-like mammal and it’s
evolved from the small number of mammals that survived the mass
extinction. It’s also prey for the dinosaurs.
This is why most mammals live in trees or underground and venture out at night.
Mammals are no threat to the dinosaurs. Nothing on earth can challenge the dinosaur’s
dominance, nothing on earth.
A lump of space rock, a large one, about 10 kilometres
across, bigger than Mount Everest, heading straight to the earth. It’s heading
to the Gulf of Mexico, just off the Yucatan Peninsula. At the moment of impact,
the asteroid’s back edge is still at nearly 11,000 meters, the same height as a
commercial aircraft flies.
The asteroid strikes with such immense force that it
destroys everything that it hits. Even the asteroid itself instantly vaporizes.
The impact unleashes the energy of millions of nuclear weapons.
No-where is safe, not even up here. Some of these boulders
are as big as entire city blocks. The blast wave races out from the impact zone
like shrapnel from an exploding bomb. Minutes after impact, thousands of kilometres
from where the asteroids struck.
The earth is under attack from every direction. Boulders rain
down, earth quakes shake the ground and tsunami batter the coasts. But the onslaught
has only just begun. The plume of molten rock and dust spreads out and engulfs
the planet. The entire sky is acting like a giant sunlit. The earth’s surface
heats up to 275 degrees. Vegetation begins to spontaneously ignite. Even months
after the impact, smoke and ash still block out the sun’s rays. With less
sunlight, plants died and the animals that eat them starve. Against this onslaught, it’s hard to see how
anything can survive.
The dinosaurs, a hundred and sixty-five million year of
reign is over. But the dinosaur demise is an opportunity for another species,
mammals. By living underground they’ve avoided the heat in the fires and by
eating anything and everything they thrive while more selective eaters
die. These are the unlikely inheritors
of the dinosaur’s crown. As one story ends, another begins. With the dinosaurs out of the way, this could
be our ancestor’s chance.
The dinosaurs are long dead and the planet is peaceful. In this
new world, our mammal ancestors are evolving.
This lake 47 million years ago in what will one day be
Germany should be the perfect place to spot them. This is not the mammals we
saw earlier. Its eyes and brain are bigger. This is Darwinian smasher lay or
EDA. She looks nothing like us but fossil evidence from our own time tells us
these creatures could evolve into monkeys, apes and eventually humans. We are looking back through 47 million years
of evolution to what may be one of our earliest known ancestors. The lake sits
on a volcanic crater. It belches out noxious gas. Now the lake that killed her
will preserve her in its oxygen depleted deaths. One day when the water has
gone and Eder is fossilized in stone, we will discover them and recognize in
this primitive primate what could be the very beginning of our own story, the
story of human.
We’re closer to understanding how everything we’ve seen ocean’s
bacteria to walking fish and subterranean rodents leads to us and to understanding
how our planet was made.
47 million years ago and the atmosphere is much like our
own. The temperature is 24 degree Celsius and a day lasts just under 24 hours. The
earth we are looking at now it almost identical to the planet we call home.
The earth’s plates have been on the move again with the
continents on their back. India moves north
towards Asia. The Indian and Asian
plates are locked in a titanic struggle. Neither plate is winning, both plates
begin to buckle. What was once a lore
contorts upwards along a two and a half thousand kilometres line. A vast mountain range rises up. These are the
Himalayas.
20 Million Years ago, this is our planet with every continent
every ocean just as we know it, except there is one thing missing, us.
For humans to evolve
something somewhere down there has to change.
4 million years ago
Along Africa’s east coast between the plates that make up
the earth’s crust, a great rift opens up. The rift stretches nearly 6,000
kilometres. Along its edge mountains grow.
The growing mountains act like wall. They stopped
moisture from the Indian Ocean passing over the land. It’s getting hotter and
drier. The lush rain forest is becoming arid savannah. The new hotter climate destroys
the creature’s habitat. It forces them to search further afield for food to
stop dragging their knuckles on the floor like Apes. To stand and walk on feet,
it’s the most important step in the human story. This mountain range along Africa’s
East Coast could be the reason we walk on two feet. It seems incredible. The random movement of
two plates may have kick-started a chain events that will lead to the first
human.
1.5 million years ago.
The man and child, it could be scene from our own time but it’s one and a half million
years ago. These are the early species of human called Homo erectus and these
are the first foot prints like our own. Civilizations past and present everyone
that’s ever lived the greatest inventions, the most brilliant ideas human
history in all its complexity and splendour begins here and now.
70 thousand years ago.
The climate changes again. Sea levels fall the
gap between Africa and Arabia shrinks down to just 13 Kilometres. The Red Sea
is narrow and shallow enough for this small group to cross out of Africa. They are
another later species of human called Homo sapiens. They have made it across. Scientists
believe every man woman and child outside of Africa is descended from these 200
or so individuals. Over time our ancestors multiply and spread out to India,
Asia and to Europe. But while human head north, a giant wall of ice travels
south.
40 thousand year age.
Europe, our Homo sapiens ancestors are arriving
only to find a world that’s changing fast. It’s getting colder. It should be
the height of summer but the plants are frostbitten, the rivers are frozen. Natural
changes in the Earth’s orbit. CO2 levels and the flow of warm water around the
planet conspire to lower the earth’s temperature. The earth and its inhabitants
enter an ice age. Places as high skyscrapers creep over the northern hemisphere
at 30 centimetre a day. Slow and powerful, they sculpt the landscape as they
move over it gouging out great depressions. The planet will never look the same
again.
20 thousand years ago.
They grind to a halt. Much of the Northern Hemisphere is covered by
ice sheets up to two and a half kilometres thick. With trillions of gallons of
water locked up as ice. Sea levels fall. A strip of land emerges from the ocean
between Siberia and Alaska. It’s a bridge between to vast continents. A gateway
that takes humans from Asia to a new world, America. It’s the last great
continent to be colonized, the last great human migration and somewhere down
there are the first Americans.
14 thousand years ago.
The changes that triggered the ice age go into
reverse. As the ice retreats it reveals a very different northern hemisphere. The
glaciers gouged out huge depressions. Now they fill with water to become North
America’s great lakes.
6 thousand year ago.
The ice retreats back to the poles to the Arctic
and Antarctic.
Today……
After four and a half billion year’s journey we’ve
made it. We’re back home. This is our world. Our time. Now for the first time
we can peace together our planets incredible story. We can understand how and
why everything we see around us is here today. From the skies above us to water
the essential ingredient for life, the ground beneath our feet and finally
life. The spectacular result of a chain
of catastrophes and coincidences. Each triumph, each disaster is a step on the
trail that leads us here. To each and every one of us right now. The earth’s
story doesn’t end here. A lot has happened but there’s more to come. The earth
will live for at least another four and a half billion years. Everything we’ve
seen on our journey is only half the story. Just imagine what wonders, what
terrors, what strange creatures lie ahead for our restless creative planet. The
next chapter of earth’s story is still to be written.
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