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 piece 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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