00:00History teaches us that a supercontinent existed about 273 to 300 million years ago.
00:08At that time, all the continents of the Earth were grouped and formed a harmonious unity.
00:14This gigantic ensemble was called Pangaea, or Pangaea, if we prefer a more sophisticated version.
00:21This term derives from ancient Greek, meaning the whole Earth.
00:25Pangaea was surrounded by a vast ocean called Pantalasa.
00:29Thus, the entirety of our planet was composed of a huge unique continent,
00:33bordered by a colossal expanse of water.
00:36This supercontinent had the shape of a gigantic C stretching from one end to the other of our globe.
00:41However, as in any evolution, things have changed.
00:45About 200 million years ago, at the beginning of the Jurassic era, that of the dinosaurs,
00:50Pangaea began its fragmentation.
00:53Contrary to the simplistic idea that continents would passively drift like icebergs,
00:58this separation gave birth to the current continents.
01:01This process also shaped the Atlantic and Indian Oceans.
01:08It was in 1912 that Alfred Wegener, a German meteorologist,
01:12presented for the first time the history of Pangaea.
01:15But how could he reconstruct events so distant in time?
01:19Visualize the core of the Earth as a gigantic chimney that emits an intense heat.
01:24This heat generates particular convection currents in the outer layer of the planet.
01:29We can assimilate this layer, the terrestrial crust,
01:32to a vast puzzle made up of multiple embedded pieces.
01:36The hot currents cause the movement of these pieces of the puzzle,
01:39which are called tectonic plates.
01:42Sometimes they move away, sometimes they collide,
01:45and other times they slide against each other.
01:48It looks like an incessant dance that takes place under our feet.
01:52One day, Wegener observed the contours of the continents
01:55and realized that the coasts of South America and Africa seemed to be intertwined.
01:59And indeed, it was the case.
02:02He then imagined that in the past,
02:04all continents were united in one and the same terrestrial mass.
02:10However, he could not simply advance this idea without providing proof.
02:14But then, how do we know that the pangea really existed?
02:18Well, several clues have allowed us to reach this remarkable discovery.
02:22One of them is comparable to a puzzle whose pieces fit together perfectly.
02:27Observe the current shapes of the continents.
02:30You will notice that they could almost completely fit together.
02:34Of course, their contours have evolved over time.
02:37This happened millions of years ago,
02:40and since then, the waters have eroded the shores.
02:43Despite everything, we still clearly distinguish their complementarity.
02:47Another clue lies in the study of fossils.
02:50We know that many prehistoric animals left traces behind them,
02:54allowing us to trace their history and identify the species that existed in the past.
02:59When scientists compared the fossils from different continents,
03:03they found a striking similarity.
03:06They belonged to the same group of animals,
03:09although they were discovered thousands of kilometers apart.
03:13It would be absurd to imagine that these animals crossed the oceans while swimming.
03:17In addition, it is unlikely that this type of animal appeared simultaneously in several places.
03:24And finally, the mountains.
03:26Imagine diving into the depths of the oceans,
03:29and discovering immense mountain ranges.
03:32These underwater reliefs and these abyssal pits
03:35look like scars showing the movement of tectonic plates.
03:39They are an additional proof that the continents are part of a much larger set.
03:44When you gather all these elements, the image becomes clear.
03:48The terrestrial continents used to form a single and even supercontinent.
03:52Since then, they have moved away from each other,
03:55but the traces of this formidable adventure remain visible in the contours of the coasts,
03:59the rocky formations they left behind them, and many other clues.
04:03It may seem obvious today,
04:06but at the time of Wegener's discovery, there were other theories.
04:10Some imagined that the continents had sunk to create the oceans.
04:14Wegener, on the other hand, had a different approach.
04:17He argued that the continents were in perpetual motion.
04:21He even forged an elegant expression to illustrate it,
04:24the drift of the continents.
04:27Subsequently, another scientist, Alexander Dutoy, joined Wegener.
04:33He brought a new perspective by suggesting the existence of two original continents,
04:38the North Laurasia and the South Gondwana.
04:41But the real revolution only occurred in the 1960s,
04:45when researchers discovered the key concept of this theory, the tectonic plates.
04:50This discovery finally allowed to confirm the ideas advanced by Wegener and Dutoy,
04:55and 50 years later, the theory was definitively validated.
04:59With time, our understanding of the planet has considerably enriched.
05:03We have discovered that the Earth had known several supercontinents throughout its history.
05:07Long before the Pangea, about a billion years ago,
05:10existed the megacontinent of Rodinia.
05:13Later, the Panoti appeared some 600 million years ago.
05:19What is fascinating is that the drift of the continents is not about to end.
05:24The continents continue to move constantly.
05:27Africa is slowly moving towards Europe,
05:30while Australia seems to be playing a tampon game with Southeast Asia.
05:35And do you know what awaits us?
05:37The formation of a new supercontinent.
05:40How will this next supercontinent emerge?
05:43Four main scenarios are drawn.
05:45New Pangea, Pangea Prochaine, Aurica and Amazia.
05:49Although these names evoke those of superheroes,
05:52they actually represent different possible configurations for the assembly of continents.
05:57Let's explore these hypotheses.
05:58Let's start with the new Pangea.
06:00Imagine the Atlantic Ocean on one side and the Pacific Ocean on the other.
06:04If things continue on their course, the Atlantic will widen more,
06:08while the Pacific will gradually shrink.
06:12In this case, the Americas, the northern part and the southern part,
06:16will end up getting closer.
06:18The Antarctic, on the other hand, will not remain on the margins.
06:21It will begin a drift north and take part in this new configuration.
06:28The Americas, accompanied by the Antarctic drifting north,
06:31will probably collide with Africa and Europe.
06:34And so, a brand new supercontinent will emerge.
06:38Now let's move on to the next Pangea.
06:41In the future, the Atlantic Ocean could get tired of its width
06:45and decide to tighten its belt a little.
06:47There are areas where the ocean floor slides under the continents,
06:52like underwater secret passages.
06:54These zones, called subduction zones,
06:58could multiply along the east coast of the Americas.
07:02If this happens, Europe and Africa and the American continent
07:06could gather again to form a supercontinent,
07:09which would then be surrounded by the Pacific Ocean.
07:12The next supercontinent, potentially envisageable, is that of Aurica.
07:17In this scenario, the Atlantic and Pacific Oceans could close again,
07:22as if they decided to take a break.
07:25But rest assured, because when an ocean disappears, another can appear.
07:29In this particular case, a brand new ocean would emerge to take its place.
07:35Imagine a huge crack crossing Asia,
07:39like a lightning bolt that opens.
07:42This crack, known as the Asian Rift Pane,
07:45would give birth to a new ocean.
07:48And with this ocean, a supercontinent would emerge,
07:51named Aurica.
07:53Australia is currently drifting north,
07:55as if it was looking for an ideal place in the heart of our planet.
07:59East Asia and America could join hand in hand.
08:03Then, Europe and Africa could connect to the Americas,
08:07and thus Aurica would be born.
08:10Finally, Asia.
08:12This supercontinent could emerge if some tectonic plates moved north,
08:16bringing with them Africa and Australia.
08:19All these territories would gather around the North Pole.
08:22With the exception of Antarctica,
08:24all continents could thus gather.
08:27Even if they meet around the North Pole,
08:30the oceans would not be completely closed.
08:33The Atlantic and the Pacific would remain open.
08:36The formation of this great gathering depends on the tectonic movements of the Earth.
08:40So far, the scenario of the New Rift seems the most plausible.
08:44All this also depends on the events that occurred after the fragmentation of the Rift.
08:48And when this new supercontinent takes shape,
08:51what will happen to the climate?
08:53How will the oceans react?
08:55And what will happen to animals and plants?
08:58These questions arouse our curiosity.
09:00But who can predict it?
09:02Maybe one day, our descendants will contemplate a map of the world
09:05where this extraordinary journey will have closed the loop.
09:08Keep feeding your curiosity and stay tuned
09:11for the next 100 million years.
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