Origen de la Tierra HD - Documental Completo 2016

Earth, as far as we know, is the only habitat with life in the universe. Why? What makes our planet so special? The answers are hidden in the distant past of the Earth. To find them, we must go back in time, see the first humans who wandered the Earth, move on continents in a collision course, face killer dinosaurs,

immerse ourselves in oceans full of strange forms of life feel the cold and freezing of the glaciers and experience the fury of attacks of cosmic missiles we must travel in time until we reach the birth of the same earth then we can rebuild together the incredible history of our planet and discover why all this all of us are here the formation of the earth

Our journey begins almost 5 billion years ago. But this cannot be true. There is no trace of our beautiful blue planet. Only a rising star, our sun, surrounded by a lot of dust. We have arrived too early, even before the Earth was formed. If we accelerate time, we can see how gravity turns dust into small rocks.

It seems almost impossible that something as complex as a planet is made of nothing more than dust and rocks. For millions of years gravity was forming these rocks to form the Earth, one of at least 100 planets orbiting the Sun. But 4,540 million years ago our planet looked more like hell than a home.

The temperature is close to 1200 degrees Celsius. There is no air, only carbon dioxide, nitrogen and water vapor. It is so toxic and so hot that if we approached it further we would be engulfed and suffocated in seconds.

The newly born planet is a boiling ball of liquid rock. There are practically no solid surfaces, only an endless ocean of lava. A young planet called Theia comes directly to us. It is the size of Mars and travels at almost 15 km per second, 20 times faster than a bullet. The gravity of the intruder deforms the surface of the Earth.

The wave of the collision is rising all over the planet. It is as if both young planets became liquid. Billions of tons of debris are scattered through space. But over a thousand years gravity operates its magic and the debris are transformed into a ring of red, hot and rocky dust that surrounds the Earth.

From the ring, a ball of more than 3,000 km in diameter is formed. We are witnessing the birth of our Moon. It is much closer than the Moon we see in our time, at only 22,000 km instead of approximately 400,000. The Sun rises on a Earth in the process of cooling and sets only three hours after its departure.

The impact has made the Earth rotate so fast that a whole day only lasts six hours. Days go by fast, but the Earth changes slowly. To understand the birth of our planet, we must advance millions of years. A meteor shower. 3900 million years ago, we suffered the attack of the remains that remained of the formation of the solar system.

Look at these strange crystals that are inside the meteorites. They look like grains of salt, the same we use for fried potatoes. But inside there are tiny drops of water. It seems that these deadly missiles could contain the vital ingredient of life on Earth. Each meteorite contains only a small amount of water, but the bombing of millions of them for more than 20 million years forms water pools.

This is overflowing on solid ground. The core of the earth continues to melt, but its surface has cooled down to reach between 70 and 80 degrees, enough to form a crust. In the future, this will be the water that we drink every time we drink. Every sump, every puddle, every drop of water in the oceans has thousands of millions of years of antiquity.

And it could have traveled millions of kilometers to get to us inside a meteorite. The Earth now has a more familiar appearance, but it is still a dangerous place. That wind is fast, perhaps more than the most destructive hurricane of our days. It is a mega storm, shaken by the rapid rotation of the planet.

The Moon is so close to Earth that its gravity is overwhelming. It creates huge tides that run across the planet's surface. But over time, the Moon moves away, the waters calm down and the planet slows down its rotation. 700 million years after the birth of the planet,

The waters that create life cover its surface. But it's not just water. There's something else down there. Small islands that seem to have emerged out of nowhere. Until... ...melted rocks erupt through the crust and rise over the ocean.

Over time, lava cools down and forms a volcanic island. This is how the islands were formed. In the future, they will unite to configure the first continents. This infant planet is made up of earth and water. It begins to resemble the planet we call our home. But the atmosphere is toxic and the temperature suffocating. Nothing could live here.

Meteorites. Its rain lasts since the formation of the planet. But at this moment, 3.8 billion years ago, the assault enters a new more violent phase. Something has disturbed the orbits of these meteorites. They had already brought water, but now they contribute something more.

As they dissolve, the meteorites release their minerals and transport carbon and primitive proteins, amino acids from outer space reaching the bottom of the ocean. There everything is dark, because the sun's rays do not reach beyond 300 meters of depth and the temperature is close to zero degrees. This must be a mirage, a city of submarine chimneys.

It is not smoke, but a type of hot liquid. The sea water has been filtered to the earth's crust through its cracks. There it is heated and at its pace it collects gases and minerals. The powerful mixture comes back to the sea and creates these towers. If we add the minerals and the chemical elements of the meteorites to this, the water has become a chemical broth.

It is impossible to know how or when, but somehow these chemical substances came together to generate life. Now the water is full of microscopic organisms. These unicellular bacteria are the first forms of life on Earth. A decisive moment in the formation of the planet. Microscopic life is developing.

But then, for hundreds of millions of years, nothing changes. There is no progress, nor evolutionary progress. The only living beings are unicellular bacteria. To find more complex lives, we would need to jump in time, to 3500 million years ago, and to a shallow ocean.

They look like rocks or even plants. They seem to grow from the seabed. Each one is a mountain of living bacteria, colonies called stromatolites. As by magic, these bacteria transform the sunlight into food.

This process, called photosynthesis, uses the aluminum energy to convert carbon dioxide and water into glucose. A simple form of sugar, similar to what we put in coffee. From this magical transformation, a product emerges, a gas called oxygen. Under the water, little by little, the stromatolites fill the sea with oxygen.

In turn, oxygen turns the remains of iron from the water into oxide. This oxide covers the seabed, forming deposits of iron rock. One day we will use this mineral to build bridges, ships and skyscrapers. On the waters, oxygen is transformed into atmosphere.

These stromatolites are creating the most important element for life on Earth. Without them, there would be practically no more form of life. When we breathe again, we will do it thanks to these colonies of ancient bacteria. During the next two billion years, oxygen levels continue to rise. And as the planet rotates slower, days become longer.

now last at least 16 hours. We are discovering that forming a planet takes a long time. 1,500 million years ago, 3000 after the birth of the planet, there are still no complex forms of life. Neither plants, nor dinosaurs, nor human beings. But the Earth has something that no other planet in this solar system has: a force with the power to change everything.

Our planet is a beautiful blue ball sprinkled with volcanic islands. 1,500 million years ago it housed a primitive life. For millions of years we notice that something is reconfiguring the islands. Hidden under the ocean, the earth's crust has been divided into large plates. Below, the core of the earth remains active. It is hotter than the surface of the sun.

and that heat generates movement in the rocks under the crust. These movements pull and push the plates through the globe and with them transport islands and oceans. Millions of years pass, during which we see that our planet seems active, changing, alive. More than 400 million years later, a new and great continent called Rodinia is formed.

In the shallow waters of Rodinia, stromatolites have been exercising their magic for more than two billion years and pumping oxygen into the atmosphere. The temperature is 30 degrees Celsius and the days last 18 hours. But this is more like Mars than Earth. To find life, we will have to keep moving forward in time.

The state of Washington 750 million years ago. Some force from the ocean depth is squaring the earth's crust. It's like the world was making triceps. There's only one thing with the power to do this: the heat. It escapes from the melted core of the earth, stretching and weakening the crust. Centimeter after centimeter, year after year,

The great supercontinent splits in two. The intense geological activity has generated a large number of volcanoes that release carbon dioxide into the atmosphere. There are gases and smoke everywhere. All that carbon dioxide is mixed with water to produce acid rain. Rocks absorb it, including carbon dioxide.

At this time, on Earth, there are a lot of rocks that have flourished after the continent's fracture. So many that carbon dioxide is absorbed and is trapped in the rocks of the Earth. There is not enough carbon dioxide in the atmosphere to catch the heat of the sun and preserve it on the planet. In a few million years, the temperature drops suddenly, to 50 degrees below zero.

This ice-cold ice is the south of Australia 650 million years ago. It is the beginning of what scientists call the theory of the Earth-snowball. A period that they believe was the longest and most intense ice age that the planet has suffered. A vast wall of ice thousands of meters high. The ice is unstoppable. The more ice,

the more the light of the sun is reflected out of the planet and the faster the ice spreads. There is a second layer of ice just as high. Both extend from the poles, one to the other to be found in the equator. At this time the whole planet has been wrapped in a layer of ice 3 kilometers high. First, the planet was an incandescent fireball, now it is an ice ball.

practically all the sunlight and the heat is reflected and returns to space but nothing lasts forever something must free the earth from this cold prison and when it does who knows if life will have survived under the ice the surface is cold but the core is still at temperatures higher than the sun

Volcanoes have been erupting since the world began to freeze. But until now, neither its heat nor its power have had an effect on the ice. Volcanoes expel thousands of millions of tons of carbon dioxide. Before the Great Glaciation, the rocks of the Earth absorbed most of the CO2. But now, with the rocks wrapped in ice, nothing absorbs the gas. So this fills the atmosphere.

like a blanket, catches the heat of the sun of the whole planet. The temperatures are rising until now, 15 million years later, the ice begins to melt. It is believed that during the ice-cold period, the ice sunk the crust and that when it melted, the crust rose. This created cracks and weak points and more and more volcanoes.

Volcanoes release more carbon dioxide and make the temperature rise even more. The melt reaches its point. Oxygen levels are shot. Thanks to a series of chemical reactions, ice has created oxygen. While the planet was frozen, the ultraviolet rays of the sun reacted with water molecules in the ice to produce a chemical compound rich in oxygen.

is hydrogen peroxide, the same product with which we lighten our hair. Now, while the ice melts, hydrogen peroxide decomposes and releases huge amounts of oxygen. The earth is awakening and it is a very different place.

At that moment, 600 million years ago, the atmosphere is warmer. Like on a summer day. And the days last about 22 hours. If we add all this water, we get the perfect recipe for life.

Before the Earth was a snowball, the primitive bacteria had emerged in the oceans. But it is certain that they could not have survived at an ice age 75 times longer than the entire history of humanity. If something has lasted, the place where there will probably be more life is where we saw it for the last time: in the ocean. At that moment, 540 million years ago, in an ocean full of oxygen,

Those primitive bacteria have evolved. A handful of them must have resisted the granulation. There are plants everywhere. And something else. It looks like some kind of sclerite sloth. It's called: Wewaxia. An example of a new generation of complex multicellular organisms. We are entering one of the most dynamic periods in the history of the Earth. The Cambrian explosion.

The growing levels of oxygen allow creatures to grow and develop bone skeletons. There are worms, sponges and this. They are trilobites, distant relatives of insects, lobsters and even scorpions. Life in the oceans flourishes from microscopic bacteria to monsters like this.

It is an Anomalocaris. It measures about 60 centimeters in length. Look at its large eyes, its sharp teeth like knives, and its sharp limbs. The only thing the Anomalocaris has to do is grab its boot. The trilobite cannot turn around and its soft abdomen is exposed. These are picaeas.

They only measure about 5 cm long, but they have what could be the first dorsal spine. For millions of years, the simple structure of this creature will evolve until it becomes the dorsal spine that allows us to rise today. We sunk into the ocean waiting to find ruins of life. Instead, we have entered a life-giving world in which trilobites are born in waste

and the monsters are around. The creatures begin to adopt familiar aspects. Under the waves there are tens of thousands of animal and plant species. The progress of life seems unstoppable. We seek life on firm ground. 460 million years ago the plates move again. Below there is a new continent: Gondwana.

With a warm temperature of 30 degrees and levels of oxygen close to the current ones, these lands should be covered with plants and reptile creatures. But there is not much, except a few algae formations. There is only one explanation: the sun, whose deadly radiation inflames the surface.

The complex forms of life we have seen in the ocean are not possible on solid ground. But 50 km above, where the rays penetrate the atmosphere of the Earth, something strange is happening. When oxygen is hit by the sun's radiation, it turns into another type of gas called ozone. This gas forms a mantle around the entire planet. This ozone layer absorbs lethal radiation.

About 120 million years later, the ozone layer begins to thicken and manages to prevent more and more amounts of radiation from reaching the surface of the Earth. Without ozone, life on solid Earth would not exist. Now, shielded by radiation, life is blooming. These small, mossy fragments are the first earth plants.

By expelling more oxygen, the levels of this gas rise rapidly. 375 million years ago. There is something down there, in the water. It moves. Nothing. It is a strange fish called Tiktaalik. Its neck allows it to incorporate.

uses its fins as if they were legs and comes out of the water where the plant life is in its apogee. For more than 15 million years these creatures called tetrapods evolve, their limbs strengthen and go more and more time out of the water. Until 360 million years ago they make their home from the ground. All quadrupedal vertebrates will evolve from a creature like this.

Dinosaurs, birds, mammals... And finally, you and me. Look where we look, there are mosses and spines. Some at least 30 meters high. It is a seed carried by the wind. So far, the plants have been reproduced by means of spores, unicellular particles that need a lot of water to survive and grow.

but this seed is located kilometers from the water this embryonic plant carries the water and food it needs with it unlike a spore this seed can survive away from water for months even years the humble seeds spread life around the planet and all these trees and mottled expel even more oxygen

We could stop here and take a breath. Here we could live in this moment. We have traveled a long stretch from that pile of dust and burning rocks to a blue and green planet overflowing with life. There are no humans yet, but yes, fish, plants and this. It is a libellum, a libellum the size of an eagle.

This giant is called Meganeura. Its ancient legs have evolved to become wings, which expand the territory of the libellum hunting to an extensive area. There are a thousand feet, spiders, all kinds of bugs. These creatures, called arthropods, were the first to step on solid ground. They have been here for hundreds of millions of years.

They are almost identical to the bugs that invade our homes these days, except for one big difference. Like the Meganeura, they are monsters. We have come into a world lost in giants, in which the Nippies are two meters long and the scorpions are the size of wolves. All the oxygen in the atmosphere allows their respiratory systems to be more efficient, which facilitates the growth of their bodies.

and the Hilonomus, a creature with the appearance of a lizard. The creatures we have seen so far put their eggs in the water. However, these eggs contain all the water and nutrients that the Hilonomus offspring need. The babies are raised in their own autonomous lagoon. The egg is one of the main evolutionary advances.

Now the animals can leave the water and conquer the continent. This baby of Hilonomus will lead the way. It is a new type of creature, a reptile. Inevitably, life leads to death. There is so much dead plant matter that it accumulates and degenerates into dense layers of rotten matter.

For hundreds of millions of years, the rocks will cover these layers. The heat of the core of the earth and the pressure of the rocks on top will turn the dead plants into coal slabs. Every piece of coal that we burn to heat our homes and make our power plants work is made up of plants that perished 300 million years ago.

hidden between the matter in decomposition, more life arises. Then the seeds will germinate, the plants will grow and this páramo will revive. Life seems to have conquered the planet. A herd of creatures graze in the Siberian meadows. They are not dinosaurs and will not step on the earth until within 20 million years, but they are big.

evolution has taken a big leap forward the little lizards we saw before are now giant reptiles those are scutosauri some distant relatives of the turtles are herbivores if herbivores seem so hard predators must be very aggressive is a gorgonopsis a prehistoric murder machine perfectly designed

The teeth like sables of the gorgonopsis have hurt the scutosaur The predator watches over his prey, which is weakening due to the loss of blood Until... a moment... He withdraws Something strange is happening The ground is heating up There must be a huge pressure under the surface

There is lava, but it does not come from a single volcano. The entire environment is in eruption. It is a basalt rift. An enormous column rises from the interior of the earth, pushing the molten rock through cracks in the earth's crust. The exuberant paradise is now an inert hell. The scutosaurids and the gorgonopsids are dead.

are the first victims of the largest mass extinction that the world has witnessed: the Permian extinction. On the other side of the continent of Goduana, it is as if nothing had happened. Snow. Although the temperature is about 20 degrees Celsius. It is not snow, but ash that falls from eruptions 16,000 kilometers away.

The incandescent ash suffocates and kills animals all over the world. The atmosphere is full of sulfur dioxide from the eruptions. When it rains, the gas turns into sulfuric acid and burns everything that falls. At first it seemed that it was a local disaster, but now it is global. The Iberian eruptions increase the levels of carbon dioxide on Earth. The atmosphere is rekindled.

Water evaporates and vegetation perishes. We thought that life had finally been consolidated on the planet. But it seems that we are wrong. There are no signs of life on the continent. Although in the oceans this cannot be true. The oceans are turning pink. And the plants, the trilobites, the predators, they have all disappeared.

Everything except these pink algae. The new, warmer atmosphere must have heated the oceans depriving them of oxygen. Now nothing, except algae, survives in the stagnant waters. Siberian eruptions are transforming the entire planet. Nothing, not even the deepest bottom of the ocean, is out of reach. Look, bubbles. But it is not oxygen, but methane.

that escapes from the large deposits of this gas under the seabed. Methane is a greenhouse gas, at least 20 times more deadly than carbon dioxide. Until now, this gas had been frozen, but as the sea temperature increases, it begins to melt.

released into the atmosphere, this powerful gas makes the temperatures rise even more, up to almost 40 degrees, 6 more than before the Siberian eruptions. Now even the creatures that have survived are condemned. 500,000 years have passed since the first eruptions. During all this time, almost half a million years, lava has been pouring.

now covers a surface equivalent to that of the United States, with a layer of molten rock 6 kilometers deep. 95% of life has been liquidated. Only a handful of creatures survive, thanks to which they managed to take refuge under the face of the earth and feed on anything. But everything else is dead.

250 million years ago we return to the starting point an inert planet, almost. 50 million years have passed since practically all life on earth was eliminated and the planet has transformed 200 million years ago there is only one supercontinent called Pangea that extends from pole to pole

After the trauma of mass extinction, the planet is healing. Temperatures stabilize, acid rain is neutralizing and vegetation returns. With 95% of all life on Earth gone, the land is ready for the emergence of a new species.

A species that will dominate the planet like no other has done or has done since then. The dinosaurs. These dinosaurs are called "amosaurians". Like all their congeners, they have evolved from the handful of reptiles that survived the Permian extinction. They are 4.5 meters high and their size makes them slow and vulnerable. A Dilophosaur, two of them.

They are small and fast. The hamosaur is too much food for a Dilophosaurus, but not for two. Dinosaurs have repopulated the Earth, but no species can submit to this restless and volatile planet. The Earth's crust is thinning at this point, it is expelling lava,

and shakes with earthquakes, as if it were being tensed by an invisible force. And the same happens, until what will later be the east coast of North America. The earth's plates are back in motion. 190 million years ago, the great supercontinent of Pangea was broken. A large portion of territory has separated, and has created a hole that fills with a new ocean called, Tethys.

that extends over what is now Middle East. Currents push nutrients to coastal waters that bathe the current Saudi Arabia, Iran, Iraq and these nutrients attract fish, millions of them. With so much life, death also comes. Dead fish and plankton, carpet the sea bed. During the next 10 million years, layers of rock will bury and warm the dead creatures.

fish and the old plankton will become oil. Every litre of fuel in our cars, every piece of plastic in the world, the paint on our walls, the carpet under our feet, even the soap we use to wash ourselves, almost all of that originated in this way. 180 million years ago, the western part of the North American platform is still moving away from the Euro-Asian platform.

It happens slowly, about two and a half centimeters per year, the same speed at which our nails grow. But if we jump back in time, we see that there is a new ocean. As well as new continents, Montreal is moving away from Marrakech and New York from West Africa. The world as we know it is taking shape.

The separation between the two continents is filled up creating a great ocean, the Atlantic. And in the middle, a volcano. We have already seen platforms move. We know that it is due to the deep currents that are under the Earth's crust. A continuous process that is taking place down there at that very moment.

The entire sea bed has split in two and along it has emerged a mountain and volcano mountain range that grows taller than the Himalayas and longer than the rocky mountains. Here the water is hot, since the lava comes out of the interior of the earth. As it cools, it creates a new mountain range and a new oceanic bed.

That is what breaks Pangea, produces the separation of the platforms and reconfigures our world. It is this geological activity that makes the Earth a creative, tireless, unique place. Every time the planet is reinvented, the survivors must adapt and evolve. Things like these are ichthyosaurs.

Their reptile ancestors lived on solid ground, but when the planet changed, they did it too. They grew fins and moved to the newly created Atlantic Ocean. It is 6 meters long and fast. It moves at about 40 km per hour. It is the fastest creature in the ocean, the most effective predator, and for 50 million years dominated the seas of the planet.

But now there is a new aspirant to the crown. The pliosaur. Longer than a bus and as heavy as a truck. Its jaws are immense, eight times more powerful than the great white shark. And its teeth are 30 centimeters long. The earth and the creatures that inhabit it have changed to be unrecognizable. What used to be solid earth, now it is the Atlantic Ocean.

It was at this very point that we could see the hamosaur graze and the dilophosaur chase its prey. The world of dinosaurs is now different, but these animals are as dominant as before, they seem invincible.

This is a mammal similar to the musaraña that has evolved from a small number of mammals that survived the mass extinction of 185 million years ago. It is one of the prey of dinosaurs, that is why most mammals live in trees or underground and only come out at night. Mammals are not a threat to dinosaurs. Nothing on earth can defy its power.

Nothing on Earth. It is a large rock fragment, very large. This asteroid is 10 kilometers in diameter. It is larger than Mount Everest and travels at more than 70,000 km per hour directly to Earth. It goes to the Gulf of Mexico, just next to the Yucatan Peninsula. It moves so fast

that as we blink we will lose the impact unless we slow down time in a fraction of a second the world will change forever in the instant of impact the asteroid has a height of almost 11,000 meters the same as the planes fly passengers the asteroid hits with such an immense force that destroys everything that touches even the asteroid itself disintegrates at the moment

The impact unleashes energy equivalent to millions of nuclear bombs. No place is safe, not even up here. Some of these big rocks are the size of whole buildings' apples. The expansive wave extends from the impact zone like a machine gun after an explosion. Minutes after the impact, thousands of kilometers from where the asteroid fell,

The earth is subjected to an attack from all sides. Rocks rain, earthquakes that shake the ground, and tsunamis that punish the coasts. But the mess has only just begun. The lava and dust patch spreads and envelops the entire planet. The entire sky acts like a gigantic solar lamp.

The surface of the earth heats up to 275 degrees and vegetation begins to spontaneously inflame. Even months after the impact, smoke and ashes still block the sun's rays. With less sunlight, plants die and animals that feed on them starve to death. Against this avalanche, it is difficult to think that something can survive.

65 million years ago, the impact has rocked, burned and made the dinosaurs explode. Its 165 million year reign has come to an end. But the end of the dinosaurs is an opportunity for other species. Mammals. By living underground, they have been saved from fire and heat.

and by eating everything they can prosper while species with more selective diets die. These are the unexpected heirs of the crown of dinosaurs. One story ends and another begins. With the dinosaurs eliminated, this could be the opportunity of our ancestors. Long ago the dinosaurs were extinct, the planet is at peace.

In this new world, our ancestors mammals evolve. 47 million years ago, this lake, located in present-day Germany, should be the perfect place to locate them. This is not like the mammals we saw before. Their eyes and their brains are bigger. This is Ida, or Darwinius massile.

It doesn't look like anything to us, but the fossil evidence of our time show us that these creatures could have evolved to become monkeys, apes and, at last, humans. We are looking forward to 47 million years of evolution, which could have been one of our first known ancestors. This lake is on the crater of a volcano that spits a harmful gas.

The same lake that ended with it will keep it in its depths without oxygen. One day, when the water is removed and Ida is fossilized in stone, we will discover it and contemplate this primitive primate as the possible first beginning of our own history, the history of human life.

We are closer to understanding how everything we have seen, from the bacteria of the ocean to the underground rodents, passing through the walking fish, takes us. And we also begin to understand how our planet was formed. 47 million years ago, the atmosphere is very similar to ours. The temperature is 24 degrees Celsius. The day lasts a little less than 24 hours.

The Earth we are looking at now is almost identical to the planet we call our home. Almost. The plates of the Earth move again with the continents behind them. India moves north, towards Asia. The Indian and Asian platforms join in a titanic fight. No desire. Both begin to clench.

What once was the ocean bed rises along a line of 2500 km. A huge mountain range rises. 1500 meters. 4500 meters. More than 8000 meters. They are the Himalayas mountains. And here we have it. The highest mountain of all. Everest.

Its summit reaches the earth's air current and is at the same altitude as the flight of passenger planes. From the water melted from its peaks, large rivers are formed: the Ganges, the Indo, the Yangtze and the Yellow River. The Himalaya is like a high tower of water. One day its rivers will provide water to almost half of the human population of the world.

20 million years ago, this is our planet. With all the continents and oceans as we know them. But there is only one thing missing: Us. The human race. For humans to evolve, something somewhere on Earth must change first. Along the East African coast, among the plates that made the Earth crash, a huge crack opens.

The crack extends approximately 6,000 kilometers. Throughout its extension, the mountains grow. There it is. It looks like a monkey, not a human. It could stay in these trees forever. But the world is changing.

The mountains act as a wall that prevents the humidity of the Indian Ocean from passing into the continent. They are getting hotter and hotter, and the climate is getting drier and drier. The lush, humid forest is becoming an arid savannah. This warmer climate destroys the habitat of these creatures and forces them to intern in the continent in search of food and to stop clinging to the ground like apes.

and to stand up and walk on two feet. It is the most important step in the history of humanity. This mountain range parallel to the coast of East Africa could be the reason why we walk on two feet. It seems incredible that the random movement of two platforms of the Earth may have triggered a succession of events that led to the appearance of the first humans.

A man and a child. This could be a scene from our time. But it occurred a million and a half years ago. This is an early human species called Homo erectus. And these are the first footprints like ours.

Past and present civilizations, all the human beings who have lived, the greatest inventions, the most ingenious ideas, human history in all its splendor and complexity begins here and now. The climate changes again. 70,000 years ago the water level dropped. The separation between Africa and Arabia decreased to 13 kilometers.

The Red Sea is narrow and shallow, enough to allow this small group to cross it and leave Africa. They belong to a posterior human species known as Homo sapiens. They have managed to cross. Scientists believe that the entire world beyond Africa was populated by the descendants of these few hundred individuals.

Over time, our ancestors reproduce and spread across India, and from there to the rest of Asia and Europe. But while humans head north, a gigantic ice barrier travels south. Europe, 40,000 years ago. Our ancestors, the Homo Sapiens, are reaching more parts of the world, where they find that the planet is changing rapidly, it is cooling down,

We should be in the middle of summer, but the plants are frozen and the rivers frozen. Natural changes in the Earth's orbit, CO2 levels and the planet's hot water currents conspire to make the Earth's temperature drop. The Earth and its inhabitants enter an age of ice.

Glaciers as high as skyscrapers invade the northern hemisphere at a speed of 30 centimeters per day. Slow but inexorable, they reconfigure the landscape as they occupy it, creating great depressions. The planet will never have the same appearance as before. Now, about 20,000 years ago, the glacial system stops.

Much of the northern hemisphere is covered with ice floes up to 2.5 km thick. With billions of liters of water converted into ice, the sea level goes down. 20,000 years ago, a strip of land emerged in the sea that separates Siberia and Alaska. It is a bridge between two great continents, a door that locks humans from Asia to a new world: America.

It is the last great colonized continent, the last great human migration. At some point down there, the first Americans are found. At that moment, 14,000 years ago, the changes that caused the glacial change are reversed. When they retreat, the ice leaves a very different northern hemisphere.

The enormous depressions created by glaciers fill up with water and become the great lakes of North America. 6000 years ago, ice returned to the poles, to the Arctic and to Antarctica. After a journey of 4,500 million years, we finally arrived. We have returned home. This is our world, our moment.

Now for the first time we can recompose the incredible history of our planet and understand the how and why of everything that surrounds us today. From the skies to the water, the essential ingredient of life, the ground we step on and finally, life. Everything is the spectacular result of a chain of catastrophes and coincidences. Each triumph,

Every disaster is a step along the path that has brought us here, to all and each one of us, to now. But the history of the Earth does not end here. Many things have happened, but there is much to come. The Earth will survive for at least another 4,500 million years. Everything we have seen on this trip is only half of the story.

Imagine the wonders, the horrors and the strange creatures that remain to see our restless and creative planet. The next chapter of the history of the Earth continues without writing.