Did you know that Earth used to have continents that no longer exist today? Millions of years ago, there were massive landmasses that have since disappeared, either sinking beneath the ocean or breaking apart to form new continents. One of these lost continents is called Zealandia, most of which is now submerged under the Pacific Ocean! There’s also a famous one called Gondwana, which eventually split into Africa, South America, Australia, and Antarctica. These changes happen because of plate tectonics, where Earth’s crust moves over time. It’s like a giant puzzle that keeps shifting, and we’re still discovering pieces of this ancient history!
00:00Do you know how many continents there are on Earth?
00:04That's an easy one, seven.
00:06But wait a second, aren't Europe and Asia one large continent, Eurasia?
00:11It looks so when you look at the world map.
00:14Well, scientists think differently.
00:16They don't just look at bodies of land sticking out of the sea.
00:20Geoscientists study the types of rock that continents are made from.
00:23When you see the world from their perspective, the number of continents actually increases.
00:28Yes, they are not a myth.
00:31Lost continents exist.
00:32Or at least they used to.
00:34They are hiding under other landmasses.
00:37Peek-a-boo!
00:38Researchers have recently discovered one continent just like that.
00:41It's called Greater Adria.
00:44Sound familiar?
00:45Yes, it has something to do with the Adriatic Sea.
00:49This lost continent is completely buried under Europe.
00:52It collided with Europe and started to sink under it a long time ago.
00:56Today, it lies beneath Italy, Greece, and the Baltics.
01:00Its size and even shape match that of Greenland, the world's largest island.
01:05But how did geoscientists find Greater Adria?
01:08It's no longer visible, but it left some clues.
01:12Parts of it were embedded in the Alps.
01:14Other chunks were incorporated into present-day Italy and Croatia,
01:18on the other side of the Adriatic Sea.
01:20Limestone rocks from the former continent started to change
01:24once they were under the European landmass.
01:27Tremendous heat and pressure spread over tens of millions of years
01:31changed their structure.
01:33Out goes the limestone, in comes the marble.
01:36All the Greek and Roman temples you admired on your summer vacation
01:39were constructed using this marble.
01:41It was sort of a going-away gift from a long-lost continent.
01:48Greater Adria camouflaged itself well for thousands of years.
01:52But other lost continents were hiding in plain sight.
01:55Have you heard of Earth's 8th continent, Zealandia?
01:59Probably not, because it sits under the surface of the Pacific Ocean.
02:0395% of Zealandia is now underwater.
02:06Can you guess where exactly?
02:08Its name is a good hint.
02:09Under New Zealand.
02:11If you open Google Maps, you can see its outline.
02:14Look for a lighter shade of blue in the ocean.
02:17It should stretch from New Caledonia to New Zealand.
02:20This bump in the ocean floor used to be above sea level.
02:24It was about two-thirds of Australia
02:26and more than twice the landmass of Greater Adria in size.
02:30We can spot Zealandia today because it hasn't sunk too low.
02:34And that's the best way to discover other lost continents.
02:38Imagine the Earth without the oceans.
02:40The bottom of the sea isn't flat.
02:42There are mountains and trenches.
02:44You could put Mount Everest in the deepest of them,
02:47and there would still be 7,000 feet between it and sea level.
02:51This trench got so deep because of a geological process called subduction.
02:56The Pacific Plate got under the Philippine Plate.
02:59Earth's crust is made out of those plates that float in a sea of molten rock.
03:04Then they bump into each other, one goes down while the other one rises.
03:09That's how Greater Adria ended up under the European continent.
03:13Our planet is constantly on the go.
03:16We don't notice this process because it happens deep beneath our feet.
03:20120 million years ago, Australia and Antarctica were a single piece of land.
03:26Yep, the coldest and one of the hottest places on Earth were once the same territory.
03:32Antarctica said goodbye to Australia, but it didn't leave empty-handed.
03:36Today, there is an oceanic plateau in the Indian Ocean.
03:40The word plateau comes from French, and it means elevated flatland.
03:45And the name of this land sounds like the title of a Hollywood movie, Broken Ridge.
03:50Long ago, it was connected to another lost continent.
03:54Scientists believe that it made a land bridge between India and Antarctica.
03:59What was this land like?
04:00The answer possibly lies in a tiny archipelago in the southern Indian Ocean.
04:06These islands are all that is left of an ancient landmass.
04:10They have a cold climate.
04:12The islands feature glaciers because they're so close to Antarctica.
04:16But in the past, the climate must have been temperate with plenty of rainfall.
04:20The animals and plants would have been similar to those that we find in tropical regions today.
04:25The lost continent's landscape probably resembled that of New Zealand.
04:30Now, while we're in the area, can you guess which continent the island state of Madagascar once belonged to?
04:37If you guessed Africa, sorry, you were wrong.
04:40Hey, don't feel bad.
04:42Look up and to the right of the map.
04:44The correct answer is India.
04:46Some 120 million years ago, I wasn't around then,
04:50India separated from the African continent and went northeast.
04:54Madagascar wasn't quick enough and ended up as an island off the southeast coast of Africa.
04:59But there is evidence of an even greater landmass, the lost continent of Mauritia.
05:06Scientists found traces of the ancient landmass under the island of Mauritius.
05:10Today, it's a tourist hotspot.
05:13But millions of years ago, it was a real hotspot.
05:16Volcanoes and all.
05:18That's how scientists were able to retrace the steppes of Mauritia.
05:21They found a mineral that exists in rocks, which lava spews out after an eruption.
05:27The long-lost land once covered the area from Mauritius to the west coast of India.
05:32Imagine if that land existed today.
05:34It would form a great mix of Indian and African cultures.
05:38The local dishes would definitely be spicy.
05:41Now, speaking of spicy, have you had Indonesian food recently?
05:45Just 50,000 years ago, southeast Asia looked much different.
05:50There was no Sumatra, Borneo, Java, or even Australia.
05:54Just Sunda and Sa'ul, two continental masses that were divided by a deepwater trench.
06:00You had the extension of mainland southeast Asia on one side and the greater Australia on the other.
06:07Back then, Bali stood at the southernmost tip of Asia.
06:10Biologists were among the first scientists to notice the split.
06:15Species developed differently on Sunda and Sa'ul.
06:18That's why Australia has unique animals, such as the kangaroo, wombat, and platypus.
06:24And did you know that a giant kangaroo once roamed the island of New Guinea?
06:29That's because, up until the end of the last age, there was a land bridge to Australia.
06:34Today, the two islands are separated by the Torres Strait.
06:37But it's quite shallow, less than 65 feet.
06:40It's a reminder that this was once a single landmass called Sa'ul.
06:45Another ocean strait that isn't too deep separates Asia from North America.
06:50The Bering Strait sits today in the place of Beringia.
06:54This ancient landmass wasn't that big.
06:56It stretched 1,000 miles from north to south.
06:59That's just a third of the driving distance from Los Angeles to New York.
07:04Beringia was important for another reason.
07:06During the Ice Ages, it connected the whole world.
07:09Water levels were 300 feet lower than they are today.
07:13If they went even lower, you could walk from the Cape of Good Hope in Africa all the way to Cape Horn in South America.
07:20Talk about the ultimate backpacking route.
07:23Today, you can hop on an airplane and fly to pretty much any place on the globe.
07:29The world has never seemed smaller, has it?
07:32Well, it has.
07:33Some 300 to 200 million years ago, we were all one world, literally.
07:38Pangaea was a supercontinent that included all of the continents.
07:43Its name is in Greek, and it simply means all Earth.
07:47But Pangaea started to crack up.
07:50The biggest gap formed between the Americas on one side and Europe and Africa on the other.
07:55Seawater soon started pouring in, and that's how we got the Atlantic Ocean.
08:00This process is by no means over.
08:03While you are watching this video, North America is drifting further and further away from Europe at the rate of one inch per year.
08:11Doesn't seem much when compared to the average human lifespan, but in the end, all the continents will reconnect with each other, forming a supercontinent.
08:21And it wouldn't be the first time in Earth history that this happens.
08:24Honestly, I'm not going to wait around for that.
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