La Antártida, ahora un vasto desierto helado, oculta bajo su manto de hielo indicios fascinantes de un mundo perdido donde prosperaban dinosaurios y criaturas prehistóricas. Hace millones de años, este continente era un lugar próspero cubierto de grandes bosques. Gigantescos titanosaurios vagaban libremente por sus valles, mientras que los protomamíferos se movían ágilmente entre la vegetación. Esta lejana época nos revela que la Antártida no siempre fue la inhóspita región que conocemos hoy.
Uno de los hallazgos más emocionantes es el Cryolophosaurus, considerado como el T-Rex de la Antártida. Este carnívoro, con sus impresionantes características, habitó durante el período jurásico y es un símbolo de la diversidad de vida que existía en un entorno completamente diferente al actual. Los fósiles descubiertos en esta región han proporcionado valiosa información sobre su fauna, ayudándonos a entender la evolución y los cambios climáticos que han transformado el continente.
El estudio de estos antiguos ecosistemas es crucial no solo para los paleontólogos, sino también para todos aquellos interesados en la historia natural del planeta. A través de la investigación, podemos aprender sobre el impacto del cambio climático en la biodiversidad y cómo los ecosistemas se adaptan a lo largo del tiempo. La Antártida es, sin duda, un testimonio de los tiempos antiguos que merece ser explorado y descubierto.
#Hashtags: #Antártida #Dinosaurios #Paleontología
**Keywords:** Antártida, dinosaurios, Cryolophosaurus, ecosistemas prehistóricos, titanosaurios, fósiles, cambio climático, historia natural, evolución, investigaciones paleontológicas.
Uno de los hallazgos más emocionantes es el Cryolophosaurus, considerado como el T-Rex de la Antártida. Este carnívoro, con sus impresionantes características, habitó durante el período jurásico y es un símbolo de la diversidad de vida que existía en un entorno completamente diferente al actual. Los fósiles descubiertos en esta región han proporcionado valiosa información sobre su fauna, ayudándonos a entender la evolución y los cambios climáticos que han transformado el continente.
El estudio de estos antiguos ecosistemas es crucial no solo para los paleontólogos, sino también para todos aquellos interesados en la historia natural del planeta. A través de la investigación, podemos aprender sobre el impacto del cambio climático en la biodiversidad y cómo los ecosistemas se adaptan a lo largo del tiempo. La Antártida es, sin duda, un testimonio de los tiempos antiguos que merece ser explorado y descubierto.
#Hashtags: #Antártida #Dinosaurios #Paleontología
**Keywords:** Antártida, dinosaurios, Cryolophosaurus, ecosistemas prehistóricos, titanosaurios, fósiles, cambio climático, historia natural, evolución, investigaciones paleontológicas.
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00:00:00ANTARCTICA
00:00:05Antarctica.
00:00:08A continent frozen in the confines of the earth,
00:00:13practically devoid of animal and plant life.
00:00:19But millions of years ago,
00:00:23this was a land of enormous dinosaurs
00:00:26that inhabited an exuberant and forest ecosystem.
00:00:34Here, agile predators hunted fast prey.
00:00:43This huge continent also served as a refuge
00:00:47for resistant creatures that survived a massive extinction
00:00:52and for giant reptiles that were more than a ton of weight.
00:01:03A team of scientists entered this lost world,
00:01:09hoping to unravel the secrets of the mysterious past of Antarctica.
00:01:14They ventured into the most inhospitable place on earth,
00:01:19where to look for fossils.
00:01:28The ancestral land.
00:01:31Dinosaurs of the frozen continent.
00:01:39More than a century ago,
00:01:41the extraction of the last fossils of a dinosaur
00:01:45contributed to changing the idea
00:01:48that Antarctica was nothing more than an inaccessible frozen territory.
00:01:53This has been one of the most extraordinary experiences of my life
00:01:58and the most difficult.
00:02:01Antarctica.
00:02:09Incredibly, this was the largest carnivore
00:02:13of the lower Jurassic on our planet.
00:02:19And it was discovered on the southernmost continent,
00:02:23of which it was thought until just 100 years ago
00:02:26that it had never housed any kind of prehistoric life.
00:02:31After the discovery of the Cryolophosaurus,
00:02:35others arrived, such as the Glacialisaurus.
00:02:39There were even signs that the largest dinosaurs on earth
00:02:43had used Antarctica as a terrestrial bridge.
00:02:52But how did the forests, plants and animals
00:02:56survive in a polar continent
00:02:59that bears four months of total darkness a year?
00:03:05And how did some Antarctic creatures manage
00:03:09to survive a massive extinction
00:03:12that ravaged life on the other continents?
00:03:19In short, how did the dinosaurs
00:03:22dominate the lost world of Antarctica?
00:03:26ANTARCTICA
00:03:32To reach the borders of the earth,
00:03:35scientists are preparing in Christchurch, New Zealand,
00:03:39the trampoline to reach the frozen continent.
00:03:45Dr. Nate Smith, along with Drs. Patty River and Libby Ives,
00:03:51will join a dozen scientists
00:03:53to carry out a summer expedition
00:03:56to the Transantarctic Mountains.
00:03:59The last time Nate was here was in 2011.
00:04:03Now he wants to repeat the success of that mission.
00:04:07It's always exciting when you get to Christchurch.
00:04:11It's when you really realize
00:04:14that you're about to travel to Antarctica to work on the ground.
00:04:18But before you go to your destination,
00:04:20you have to finish all the details.
00:04:23Safety is important.
00:04:26This is the third time that Dr. Patty River,
00:04:29a prehistoric plant expert, is going to Antarctica.
00:04:33We always have to carry walkie-talkies with us.
00:04:37So don't forget to book a pocket for a walkie-talkie.
00:04:41Right.
00:04:43For me, right now, Antarctica is that great unknown.
00:04:46It's this great red anorak.
00:04:49Right now, all the possibilities are absolutely crazy.
00:04:53Shackleton on three.
00:04:55One, two, three.
00:04:57Shackleton!
00:05:01The rocks at the top of the Transantarctic Mountains
00:05:05that surround the glaciers
00:05:07are an ideal place to look for fossils.
00:05:10This time I'm really excited to go to the Shackleton Glacier,
00:05:13a place I've never been to before.
00:05:16Because it has been a very well-known location
00:05:19in the history of Antarctic exploration,
00:05:22as well as for paleontology in the last 50 years.
00:05:27Surprisingly, this huge continent
00:05:30hasn't completely frozen up until just 15 million years ago.
00:05:38The layer of ice would completely cover the United States of America.
00:05:44The speed of the winds and low temperatures
00:05:48can't be found anywhere else on Earth.
00:05:52If you think about it,
00:05:54the amount of ice in Antarctica is enough to drive you crazy.
00:05:58The continent covers just over 14 million square kilometres,
00:06:02and about 98% of this area is covered in ice.
00:06:07But the history of how the world of ice was created
00:06:11began a long time ago, 300 million years ago.
00:06:18At that time, the world was mainly formed
00:06:21by a supercontinent called Pangea.
00:06:24It extended from the northern hemispheres
00:06:28to the frozen southern hemispheres.
00:06:31At this point in the history of the world,
00:06:33the layer of ice in Antarctica is melting
00:06:37due to an early global warming of the Earth.
00:06:47250 million years ago,
00:06:50this polar world went from being a fridge
00:06:53to becoming a greenhouse.
00:06:56And little by little, it split into two great continents.
00:06:59Eurasia, in the north,
00:07:02and Gondwana, in the south.
00:07:08But they are still not inhabited by dinosaurs.
00:07:12There is still time to get there.
00:07:15Strange and wonderful predecessors
00:07:18are already wandering through their forests and swamps.
00:07:30Among them, the most common creature of that era,
00:07:34a resistant herbivore the size of a dog called Listrosaurus.
00:07:40They occupied all of Gondwana's territory
00:07:43and were discovered in Antarctica in the late 1960s.
00:07:46They had a kind of fangs on their snouts
00:07:49and something like a beak, a short and plump tail,
00:07:52and very robust limbs.
00:08:00Here, some giant amphibians also prospered.
00:08:06Before the era of the crocodiles,
00:08:09they occupied a similar niche with a similar bite.
00:08:29They hunted smaller animals, like the Listrosaurus.
00:08:40The Listrosaurus belonged to a group of reptiles
00:08:44similar to the mammals that evolved
00:08:47to become real mammals.
00:08:53These little creatures played a key role
00:08:56in the theory of plate tectonics.
00:09:03Five decades ago,
00:09:06science did not quite accept the idea
00:09:09that the great continents were separating more and more.
00:09:13The Listrosaurus of Antarctica served as irrefutable proof
00:09:17when fossils were found thousands of kilometers away,
00:09:21in southern Africa.
00:09:24It was a great discovery to find the first Listrosaurus in the 70s
00:09:28because the theory of plate tectonics was beginning to settle
00:09:32and suddenly the same animal appears in Africa and Antarctica,
00:09:36which had a huge impact.
00:09:39We have found this animal in South Africa,
00:09:42in Antarctica, in India, in China, in Russia, in Australia.
00:09:46It is clear that this animal could not cross the oceans,
00:09:49so it had to come ashore to all those places.
00:09:53The fact of finding the same species of plants and animals
00:09:57in Antarctica that we found in other southern continents
00:10:01was the tip for the skeptics of the theory of plate tectonics
00:10:05about the position of the continents in the past
00:10:09and that still today they continue to move.
00:10:14Antarctica is the most inhospitable place on Earth
00:10:17to explore in search of fossils.
00:10:21Most of the continent is inaccessible
00:10:24since the surface is covered by huge layers of ice.
00:10:28But at some points the rock emerges from the ice.
00:10:32This is the reason why numerous expeditions
00:10:36have the Transantarctic mountains as their destination.
00:10:40Even so, their secrets are kept buried under the frozen rocks
00:10:44in the most inaccessible places.
00:10:48Millhammer, currently retired,
00:10:51spent 50 years exploring this lost world,
00:10:54full of dangers and difficulties.
00:10:58The first two trips were hard.
00:11:01You are isolated there with just a handful of people.
00:11:04But you have to choose the right people
00:11:07with whom you are going to travel to Antarctica.
00:11:10That is something I learned,
00:11:12that you have been great companions.
00:11:15We love you.
00:11:17Nate Smith was a weak student.
00:11:20But this time he leads a joint expedition.
00:11:23And one of his goals is to solve this mystery
00:11:26that intrigues the experts since they began to find fossils there.
00:11:32How could plants and animals like the Listeria survive
00:11:36in the total polar darkness of winter?
00:11:42Despite the constant displacement of the continents,
00:11:45Antarctica has never separated too much from the polar circle
00:11:49in which darkness reigns for four months a year.
00:11:54One of the eternal mysteries of Antarctic paleontology
00:11:58is to know how these ecosystems lived in high latitudes
00:12:02in a system of polar light.
00:12:13The expeditions are always carried out during the summer months
00:12:17in which they can enjoy the solar light 24 hours a day,
00:12:22so they can work with light as many hours as they want.
00:12:28After a few days of preparation in Grace Church,
00:12:31the time has come to leave.
00:12:34Antarctica is one of the hardest places in the world
00:12:38to look for fossils, and this is largely due to logistics
00:12:42to be able to get there and work on the continent.
00:12:47Smile, guys!
00:13:04It is a six-hour flight on board an American Air Force plane
00:13:09from Grace Church, New Zealand, to the frozen continent.
00:13:19Located at the northern end of the island of Ross,
00:13:23McMurdo, managed by the United States, is the largest scientific base.
00:13:28This base, which houses 200 people,
00:13:32will be their home for a week,
00:13:35in which they will prepare their trip to the Sackleton Glacier.
00:13:45It is a mixture of a remote mining settlement
00:13:49and a small liberal arts faculty.
00:13:53And it is designed to resist terrible storms.
00:13:58On the ground, scientists face real risks.
00:14:06Antarctica is such an isolated place,
00:14:09and the weather conditions are so extreme,
00:14:12that it is a very dangerous place to work,
00:14:15and you have to adopt many security measures
00:14:18and undergo a demanding training.
00:14:21One of the biggest risks is the cracks,
00:14:23huge holes that can be opened without prior notice.
00:14:33All field scientists must learn to get out of them
00:14:37by climbing in case of falling into one.
00:14:41Even in the warmest months,
00:14:44storms, very strong winds and very extreme temperatures can occur.
00:14:48That is why we follow a special training
00:14:50before we enter the terrain.
00:14:53We receive training on the cracks,
00:14:56methods to sort glaciers,
00:14:59and to be prepared for those conditions.
00:15:03Soon, living under a sack will be their world for six weeks.
00:15:11As if warning them of what awaits them,
00:15:14a strong storm falls over Antarctica.
00:15:21We have had a very bad weather,
00:15:24and we have to delay the transfer to our camp,
00:15:27and obviously we cannot fly in this weather.
00:15:31They will take everything they need
00:15:34to spend six weeks in the traditional mountains of Antarctica.
00:15:38Once the storm has passed,
00:15:41they are transported to the depths of Antarctica.
00:15:57Now they are completely alone.
00:16:00They have no one to rely on.
00:16:03They have no one to rely on.
00:16:05They are completely alone,
00:16:08hundreds of kilometers from the nearest aid,
00:16:11and thousands of miles from civilization.
00:16:17Somehow you get the feeling that you are arriving to another planet.
00:16:20Their mission is to understand
00:16:23the most transcendental mass extinction
00:16:26in the history of the planet,
00:16:29which took place 250 million years ago.
00:16:38They intend to reach a well-known crest of sacred rocks,
00:16:42which has been preserved for thousands of years.
00:16:46They intend to reach a well-known crest of Sakelton,
00:16:50called Collinson Ridge.
00:16:53With decades of experience behind him,
00:16:56Bill Hammer gave advice to Nate and his team
00:16:59before embarking on the trip.
00:17:02The hardest place to reach,
00:17:05although it will be one of your best locations,
00:17:08is Collinson Ridge.
00:17:11There we find very interesting things,
00:17:13you have to get to the glacier,
00:17:16get down here, 45 minutes on a snowmobile,
00:17:19and a one-hour hike uphill to the top.
00:17:23But today, the helicopter transfer
00:17:26makes it one of the most accessible places
00:17:29for the search for fossils.
00:17:36Many of the places we go to,
00:17:39we are the first people who have stepped on them.
00:17:41It's an indescribable feeling.
00:17:44Another amazing thing about this place
00:17:47is that if there is no wind and you move away from your companions,
00:17:50the silence is total.
00:17:59You can't find anywhere else in the world
00:18:02where it's possible to experience total silence like here,
00:18:05and it's nice, it's kind of irritating, but it's nice.
00:18:08They are divided into smaller teams.
00:18:11The sedimentologists are located
00:18:14in a mountainous cliff on the outskirts
00:18:17where a key geological event occurred.
00:18:20All of this corresponds to the lower Triassic,
00:18:23so we are facing something that is about 252 million years old
00:18:27and that is trapped in time as a sample of that flood event.
00:18:31It's incredible.
00:18:34Somewhere between where I am now
00:18:36and about three feet above me,
00:18:39between 70 and 90 percent of the plants
00:18:42and animals around the world disappeared.
00:18:48The transition between the Permian and the Triassic
00:18:51is marked by what paleontologists call
00:18:54the Great Mortality.
00:18:5770 percent of terrestrial animals died,
00:19:00as well as 95 percent of marine life.
00:19:06All because of a widespread destruction
00:19:09of forests, plants and nutrient ecosystems.
00:19:15It was a catastrophe for planet Earth.
00:19:25The mass extinction at the end of the Permian was colossal.
00:19:29Life was at the edge of the knife
00:19:32and it meant a fundamental remodeling and reorganization
00:19:34of the ecosystems.
00:19:37The expedition to Antarctica
00:19:40is looking for samples of the roots of this period,
00:19:43both earlier and later.
00:19:49At 2,100 meters,
00:19:52Pete Makovicky and Akiko Shinja
00:19:55have found a fossil of the Istrosaurus
00:19:58embedded in the frozen rock.
00:20:01We are in the process of extracting
00:20:04what we found this morning.
00:20:07We think it is an Istrosaurus,
00:20:10although it is an assumption based
00:20:13mainly on the size of the specimen.
00:20:16This discovery is just another indication
00:20:19that there were still Istrosaurus around here
00:20:22after the Great Mortality.
00:20:25It is a lineage of survivors.
00:20:30One of the few lineages of terrestrial animals
00:20:32that managed to survive
00:20:35the great extinction of the Permian.
00:20:38But how did it survive?
00:20:41And what was Antarctica like afterwards?
00:20:49Forests are disappearing all over the world
00:20:52as a hot and toxic land
00:20:55ends up with life everywhere.
00:20:57All over Siberia,
00:21:00the mantle of the earth
00:21:03spat out huge volcanic lava beds
00:21:06that covered an area
00:21:09equivalent to half the size of the United States,
00:21:12with a thickness of several kilometers.
00:21:15This activity released
00:21:18huge amounts of carbon dioxide
00:21:21that heated the temperature
00:21:24to levels exceeding 10.5 degrees Celsius.
00:21:27This created too much heat
00:21:30for the survival of most animals.
00:21:33And ultimately led to a total reorganization
00:21:36of the ecosystems.
00:21:39And we also see a general alteration
00:21:42in the communities of plants,
00:21:45so that there are no forests
00:21:48after the transition between eras.
00:21:54Only the most resistant
00:21:57and adaptable species remain.
00:22:09Ancestors of the cockroach, of course.
00:22:14And the prolacerta,
00:22:17a creature similar to a lizard
00:22:20that preceded dinosaurs and crocodiles.
00:22:23The prolacerta existed about 250 million years ago.
00:22:25It is one of the first animals found
00:22:28after the great extinction of the Permian-Triassic.
00:22:31Its name means before the lizards,
00:22:34although they are actually relatives
00:22:37of dinosaurs and crocodiles.
00:22:40It belongs to the reptile lineage,
00:22:43so in a way it is the most similar
00:22:46to a dinosaur that we find
00:22:49from the lower Triassic.
00:22:52Extracting animals from the frozen rock
00:22:55is very difficult.
00:23:00Scientists have spent a long time
00:23:03focusing on places in the world
00:23:06where access and extraction are easier.
00:23:10But on many occasions
00:23:13they stumble upon the bones by chance.
00:23:16The lost world of Antarctica
00:23:19has remained hidden
00:23:22in an inaccessible continent
00:23:25for just over a century.
00:23:28No one even suspected that Antarctica
00:23:31was covered with forests
00:23:34and that there were prehistoric animals wandering around.
00:23:38So, what changed?
00:23:42The first explorers arrived in the region.
00:23:47Robert Scott discovered the first clues in 1912.
00:23:50Scott and his team tried to get to the South Pole
00:23:53when they stumbled upon rocks
00:23:56with fossils of leaves printed on them.
00:24:00Despite the extreme conditions,
00:24:03the explorers took them with them.
00:24:07But as we know,
00:24:10Scott and his team died there,
00:24:13so the fossils of Glossopteris
00:24:15were later found on a sled
00:24:18near their corpses.
00:24:21This changed our perspective
00:24:24on Antarctica and its geological history.
00:24:27As a paleontologist,
00:24:30I think it's amazing
00:24:33that these people found these remains
00:24:36and were able to recognize their importance
00:24:39to understand that Antarctica
00:24:42had been a very different place
00:24:45in the past.
00:24:48The discovery of this plant proof
00:24:51implied that the forests had previously covered
00:24:54this great continent in warmer times.
00:25:01But how did the forests survive
00:25:04in the extremes of the polar latitudes
00:25:07where the darkness was total for months?
00:25:16Scott only found leaves in Antarctica,
00:25:19but the fossilized trees of a nearby neighbor
00:25:22can give us some clues
00:25:25that help us solve this mystery.
00:25:29There was a time when New Zealand
00:25:32was much closer to the frozen polar continent
00:25:35than it is today.
00:25:38It was part of the ancient Gondwana
00:25:41in the South, joined to Antarctica and Australia.
00:25:44About 83 million years ago,
00:25:47New Zealand tore itself apart
00:25:50anchored to its own tectonic plate
00:25:53and drifted along the South-West Pacific
00:25:56carrying a biological load
00:25:59of primitive animals and plant life.
00:26:05What are we looking for?
00:26:08We're looking for fossilized wood.
00:26:10Dr. Patti Reiber, paleobotanist,
00:26:13and Dr. Libby Ives, sedimentologist,
00:26:16visited a very rare example of
00:26:19170 million year old fossilized trees
00:26:22in the South Island, New Zealand.
00:26:26Is it possible that these fossilized trees
00:26:29are a time capsule
00:26:32and offer us a window
00:26:35to look into the ancient Antarctica?
00:26:40Look, Patti.
00:26:42What?
00:26:44Look at this.
00:26:46It's incredible.
00:26:48Between the pools that leave the tides
00:26:51there are petrified trees.
00:26:54How tall do you think they are?
00:26:57Is this the total length?
00:27:00No, this is just the central trunk.
00:27:03It's one of the few places on Earth
00:27:06where we have a fossil forest
00:27:08that hasn't been moved from where they were
00:27:11when they were living trees.
00:27:14These forests probably grew in the polar circle
00:27:17or near it when New Zealand was thousands of miles
00:27:20further south.
00:27:23What's certain is that the trees in Antarctica
00:27:26had to survive months of polar darkness.
00:27:29These are plants that grew in a dark environment
00:27:32for four months,
00:27:35and the sun didn't set for another four months.
00:27:38It's not like that today.
00:27:41How did plants manage to do that?
00:27:44To keep on living and survive?
00:27:47So, we've got this really long tree,
00:27:50and if you crouch,
00:27:53you can even see the rings.
00:27:56These rings show that the tree grew
00:27:59until it was about 90 years old
00:28:02and remained inactive for certain periods,
00:28:05like an extreme version of the current winter
00:28:08that causes the leaves to fall
00:28:11and interrupt the growth.
00:28:14Could it be a strategy of the polar winter,
00:28:17or simply a variation of a normal winter?
00:28:20To find out,
00:28:23we have to keep on investigating.
00:28:30In the Sackleton Glacier,
00:28:33Patty has found the oldest trees
00:28:35buried in the frozen rocks.
00:28:38I did study the rings of these trees,
00:28:41and what they do is they work at full speed,
00:28:44and suddenly they stop very quickly.
00:28:47It's almost instantaneous.
00:28:50The variation in the rings of the trees
00:28:53indicates these periods of extreme inactivity
00:28:56in which growth was interrupted very quickly
00:28:59compared to today.
00:29:02But this doesn't completely solve the mystery.
00:29:06Current plants and trees
00:29:09wouldn't survive this tension
00:29:12and would die during the months of complete darkness.
00:29:15How did they manage to come back to life
00:29:18with such long periods without doing photosynthesis?
00:29:23There is an old lineage plant
00:29:26that could help us.
00:29:29The Ginkgo tree.
00:29:32The only survivor
00:29:35of the Triassic period
00:29:38and direct descendant of its prehistoric cousin
00:29:41solves the mystery.
00:29:45Scientists introduced ginkgo plants
00:29:48along with others in experimental greenhouses
00:29:51to emulate the polar seasons.
00:29:57To imitate the polar atmosphere of the Cretaceous,
00:29:59they experimented with another ingredient,
00:30:02carbon dioxide.
00:30:06The phase of the Great Morte
00:30:09at the end of the Permian period
00:30:12greatly increased CO2 levels.
00:30:15During the upper Cretaceous period,
00:30:18the current levels were still doubling.
00:30:21Surprisingly,
00:30:24ginkgo plants survived the experiment.
00:30:27They did it by absorbing more energy
00:30:30during the simulated summer
00:30:33to compensate for the simulated polar winter
00:30:36in which they were submerged in a vegetative period.
00:30:39The higher levels of CO2
00:30:42turned out to be key to their survival.
00:30:45The evidence that the Glosopteris trees
00:30:48that Scott found
00:30:51were destroyed by the Great Morte
00:30:53remains evident even today in Antarctica.
00:31:01We go from having wood everywhere,
00:31:04in these deposits of the aluvial plain,
00:31:07to having nothing at all.
00:31:10However, in the Middle Triassic,
00:31:13other plants such as the ancestors of ginkgo
00:31:16had already returned.
00:31:19The environment of toxicity
00:31:22that had ended with so many creatures
00:31:25has already dissipated
00:31:28and has been replaced by subtropical forests,
00:31:31rivers and watercourses,
00:31:34which allowed new species of aquatic creatures,
00:31:37fearsome amphibians,
00:31:40to occupy the niches of predators and prey.
00:31:43The fossils extracted from the frozen rock
00:31:45in the 1980s by Wilhammer and others
00:31:48drew a new panorama of an Antarctica
00:31:51that was recovering during this period.
00:31:55This included a giant amphibian
00:31:58the size of a crocodile
00:32:01that has not been found anywhere else on Earth,
00:32:04called Antartosuchus.
00:32:07It took more than 20 years
00:32:10to join the remains and identify them.
00:32:12I was lucky to be able to study,
00:32:15along with Bill, an animal called Antartosuchus,
00:32:18which had a skull between 75 cm and 1 m,
00:32:21so the entire animal was about 3 m long.
00:32:24If we could see it today,
00:32:27we would probably think it looks like a giant salamander,
00:32:30but these were the most common animals
00:32:33in the Middle Triassic in Antarctica.
00:32:36It is a fact that the most diverse group of animals
00:32:39that we have found to have survived
00:32:42since today we usually consider amphibians
00:32:45a barometer of environmental degradation.
00:32:48However, they have survived all the great extinctions
00:32:51since the Devonian and they did very well in the Triassic.
00:32:54But in Gondwana,
00:32:57this great amphibian was surpassed
00:33:00by a giant predator reptile.
00:33:06The Erythrosuchus.
00:33:09Although to date
00:33:12it has not been discovered in South Africa,
00:33:15it is assumed that it lived in the then-nearby Antarctica
00:33:18during the Middle Triassic.
00:33:21It is possible that this animal
00:33:24will also reach Antarctica.
00:33:27The Erythrosuchus would have been one of the largest predators
00:33:30of its time in the Triassic period.
00:33:33It was a monster of 3 m,
00:33:36with a head of almost 1 m in length,
00:33:39with longer legs
00:33:42than a crocodile,
00:33:45and teeth almost the same size as those of a Tyrannosaurus rex.
00:33:48This early reptile
00:33:51was one of the predecessors of dinosaurs
00:33:54and the super predator of its time.
00:34:08Even so,
00:34:10the Erythrosuchus is not a force
00:34:13that can be taken lightly.
00:34:30This great predator occupies a niche
00:34:33whose time is running out.
00:34:36Slowly but constantly,
00:34:39dinosaurs begin to evolve,
00:34:42small at first.
00:34:47The days of the Erythrosuchus
00:34:50are counted as the next great extinction approaches.
00:34:56Although it is not the end for some amphibians.
00:35:00The Themnospondyls are the main group
00:35:02to which the Antarctosuchus belongs.
00:35:05There are people who believe that modern amphibians,
00:35:08such as frogs and salamanders,
00:35:11actually come from the Themnospondyls.
00:35:14So somehow they are still among us,
00:35:17although these huge amphibians disappeared
00:35:20and had their apogee in the Triassic.
00:35:26Around this time,
00:35:29fossil records show a new extinction.
00:35:32This event gave rise to the transition
00:35:35between the Triassic and the Jurassic.
00:35:38At the end of the Triassic period,
00:35:41about 200 million years ago,
00:35:44perhaps up to 70% of all life forms were lost.
00:35:47The cause is still a mystery.
00:35:51It is one of the great less known extinctions
00:35:54because the dinosaurs survived it.
00:35:57So some of the first dinosaurs
00:35:59that already existed at that time
00:36:02managed to survive extinction
00:36:05because the end of the Triassic
00:36:08eliminated a large number of its competitors.
00:36:11So the success of the dinosaurs
00:36:14may be due only to the coincidence of that great extinction
00:36:17at the end of the upper Triassic.
00:36:20This event, the fourth great extinction
00:36:23that occurred on Earth from the dawn of life,
00:36:26allowed the rise of the dinosaurs,
00:36:29who were the dominant terrestrial animals on the planet.
00:36:33As the Earth recovered,
00:36:36life on the southernmost continents of Gondwana
00:36:39was different from other territories.
00:36:42But Nate and his team
00:36:45are still looking for an answer
00:36:48to how the creatures of Antarctica
00:36:51managed to survive the long polar nights.
00:36:54Unlike plants,
00:36:56animals must conserve energy
00:36:59in a totally different way.
00:37:02By making such a small number of expeditions
00:37:05to this part of the globe,
00:37:08time goes against it to find the answers.
00:37:13Back to the Shackleton Glacier.
00:37:18Luckily, this time the weather conditions
00:37:21have been favorable
00:37:23and they have been able to spend more time on the ground
00:37:26looking for clues about the mysteries of the polar vertebrates.
00:37:31But this frozen desert
00:37:34is the most inhospitable place on Earth
00:37:37to dig in search of fossils.
00:37:40Given the scarce erosion of Antarctica,
00:37:43they must look for minute traces
00:37:46on the surface of the rocks.
00:37:49When the paleontologists locate them,
00:37:51they go to electric saws to extract them.
00:37:56The first thing I saw when I walked along this slope
00:37:59is a leg.
00:38:02This here is a hind leg
00:38:05and it is quite articulated, as it would have been in life.
00:38:08So what I'm working on here is
00:38:11with an early relative of reptiles called Procolophon,
00:38:14which was a small-sized animal that dug burrows.
00:38:17So this is a kind of animal
00:38:19that fled from lower latitudes in South Africa
00:38:22to higher latitudes here in Antarctica.
00:38:31The Procolophon is a type of primitive reptile
00:38:34of a size similar to the Gila monster,
00:38:37a reptile of our time that stalks the deserts today.
00:38:43This whole block that we have cut
00:38:46contains a range of different bones.
00:38:49What we'll do is sort of clean it,
00:38:52take it and lug it back to the helicopter
00:38:55and catalog it back to Shackleton Camp.
00:38:58We'll skip one of the big blocks
00:39:01and slip it over.
00:39:08Studying a small reptile like the Procolophon
00:39:11can lead to great discoveries.
00:39:15Perhaps primitive reptiles had some property
00:39:17that helps us understand
00:39:20how some Antarctic animals survived
00:39:23the long polar nights?
00:39:27How did they orient themselves in the dark
00:39:30to hunt enough food to survive?
00:39:36If an ancient reptile could be resurrected,
00:39:39what secrets could it tell us?
00:39:43In New Zealand, there is a creature like this.
00:39:48The separation of Gondwana 80 million years ago
00:39:51left us with an animal that is still alive
00:39:54and that boasts of a very ancient lineage.
00:39:59The Tuatara.
00:40:02An extraordinarily rare reptile
00:40:05that lives without drawing attention
00:40:08in the temperate forests of this country
00:40:11of the South Pacific.
00:40:14It is the only member that remains alive
00:40:17for 70 million years.
00:40:20Today, New Zealand is located
00:40:235,000 km further north
00:40:26than when it was in a polar latitude.
00:40:29Is it possible that it still maintains some quality
00:40:32that reveals to us how its ancestors managed to survive?
00:40:38In St. Bathans, on the southern island of New Zealand,
00:40:41paleontologists have discovered
00:40:44the oldest examples of Tuatara fossils.
00:40:47We have found three fragments
00:40:50of a jaw similar to that of the Tuatara.
00:40:53They are nothing more than small pieces of just a few millimeters
00:40:56in which you can see the teeth,
00:40:59which in fact are identical to those of the current Tuatara.
00:41:02That is why we start from the hypothesis
00:41:05that they are ancestors of the Tuatara of our days,
00:41:08which seems to indicate that the history of the Tuatara
00:41:11in this country comes from far away.
00:41:14These ancient teeth of Tuatara
00:41:17show that they cut their food
00:41:20like a meat knife,
00:41:23instead of completely swallowing their prey,
00:41:26as reptiles usually do.
00:41:29It is possible that their ancestors of the Triassic
00:41:32had a much more varied diet
00:41:35and possessed the ability to chew their food.
00:41:38Perhaps that was a useful adaptation
00:41:40to survive in the dark forests of polar winter.
00:41:45However, the secret characteristic
00:41:48that modern Tuatara have in their heads
00:41:51could give us the most important clue.
00:41:54Oddly enough,
00:41:57the Tuatara has a third eye hidden by the skin
00:42:00called the parietal eye.
00:42:03It has its own cornea,
00:42:06a retina and a lens.
00:42:09As well as a nervous connection with the brain.
00:42:17In other animals,
00:42:20this third eye serves as a calendar.
00:42:23It is able to warn that the days get longer
00:42:26and the nights get shorter
00:42:29and it can be used to schedule the reproduction.
00:42:32It could also intervene in the thermal regulation
00:42:35that the hot-blooded mammals have,
00:42:38such as reptiles,
00:42:41to help them overcome the polar winter without sunlight.
00:42:45But did these adaptations exist
00:42:48among the Antarctic creatures
00:42:51to be able to survive the long polar winter?
00:42:54Resorting to a living creature
00:42:57in search of clues is due to the enormous difficulty
00:43:00of finding sufficient evidence
00:43:03in the Antarctic fossil records.
00:43:05In the 60s and 70s,
00:43:08scientists made discoveries
00:43:11that brought to light a fascinating hidden prehistoric world.
00:43:14But no trace of the dinosaurs.
00:43:19Perhaps the dinosaurs
00:43:22could not adapt in the polar regions.
00:43:25However, the absence of evidence
00:43:28is not proof of their absence.
00:43:31It took many expeditions
00:43:33to collect and prepare all those bones.
00:43:36In that area, there is very bad weather,
00:43:39the surface of the rocks freezes and defrosts,
00:43:42which makes it difficult to collect.
00:43:45It can take a long time
00:43:48until a discovery is made
00:43:51until one of those dinosaurs is identified.
00:43:54This is particularly true in Antarctica.
00:43:57In 1986,
00:44:00fossils were discovered on an Antarctic island.
00:44:03Scientists did not know what they were
00:44:06and they were stored in Argentina
00:44:09to study them in the future.
00:44:12Working meticulously,
00:44:15over time they have been fitting the pieces of the puzzle.
00:44:18In 2006,
00:44:21the name was officially given
00:44:24and it was accepted as a dinosaur,
00:44:27so it became the first to be discovered.
00:44:34It was an armored herbivore
00:44:37close relative of the ankylosaur.
00:44:45These dinosaurs wandered
00:44:48through North America,
00:44:51in the upper Cretaceous,
00:44:5470 million years ago,
00:44:57and are famous for their claw-shaped tails.
00:45:00This Antarctic relative of 6 meters
00:45:03was named Antartopelta
00:45:06and presumably jumped from South America
00:45:09to Antarctica when they were still united.
00:45:14Thus,
00:45:17the dinosaurs emigrated or evolved in Antarctica
00:45:21with or without polar adaptations.
00:45:26We know that the dinosaurs emerged
00:45:29after the fourth great extinction
00:45:31at the end of the Triassic,
00:45:34to become the dominant species
00:45:37during the Jurassic period,
00:45:40even in Antarctica. But why?
00:45:43At the dawn of the Jurassic,
00:45:46there was an important climate change
00:45:49that created a perfect environment
00:45:52for herbivorous dinosaurs,
00:45:55whose number would grow exponentially.
00:45:58This rich ecosystem was created
00:46:01180 million years ago.
00:46:10The Eurasia, the northern part,
00:46:13is separated from the southern part,
00:46:16Gondwana, with Antarctica,
00:46:19located further south.
00:46:22Between these two masses of land
00:46:25an entire sea erupts.
00:46:28The sea of Tethys
00:46:31carries humidity to the earth
00:46:34and alters the climate all over the world,
00:46:37which becomes a hot, humid and jungle place.
00:46:40The Jurassic.
00:46:51However, despite the abundant fossils
00:46:54of dinosaurs of the Jurassic period
00:46:57all over the world,
00:47:00it is still a huge effort to find them
00:47:03on the frozen rock of Antarctica.
00:47:06Many times the fossils are so poorly preserved
00:47:09that the only way to identify a prehistoric animal
00:47:12is by the teeth.
00:47:15Teeth are better preserved
00:47:18than many other parts of animals,
00:47:21as happened with this discovery
00:47:24of amphibian teeth
00:47:27I was taking a piece of bone out of here
00:47:30and I thought this was fossil wood
00:47:33because the material is very dark.
00:47:36So I was cleaning this
00:47:39and suddenly this little block fell
00:47:42to reveal this beautiful tooth of an amphibian.
00:47:45Here we clearly see a magnificent specimen
00:47:48with its teeth and without a doubt
00:47:51it is a sample that we can collect.
00:47:54This creature of the lower Jurassic
00:47:57was also discovered thanks to a single upper canine.
00:48:00It was named Tritilodon.
00:48:04Of hot blood,
00:48:07they probably had some kind of fur,
00:48:10a proto-mammal that pointed to what was to come.
00:48:15Unfortunately for the Tritilodons,
00:48:18they lived in the same time
00:48:21as the super carnivorous predator Antarctic.
00:48:28The Cryolophosaurus.
00:48:33The Terrex of Antarctica.
00:48:42In the next episode,
00:48:45the discovery of the first giant carnivore of Antarctica
00:48:48and very fast herbivores.
00:49:03The appearance of the largest dinosaurs of all time.
00:49:11While the continent of ice
00:49:14gives us the keys to some of the greatest mysteries of the Earth.
00:49:17How did the dinosaurs survive
00:49:20in the polar darkness?
00:49:23And perhaps the greatest mystery of all.
00:49:26Are the birds the living descendants of the dinosaurs?
00:49:37The lower Jurassic.
00:49:40Exuberant forests full of life
00:49:43of all shapes and sizes.
00:49:46We are not in the Amazon.
00:49:49It is the Antarctica of 190 million years ago.
00:49:53The current Antarctica is a very different place
00:49:56from what it was in the past.
00:49:59A scientific team has traveled
00:50:02to the Sackleton Glacier,
00:50:05160 kilometers long,
00:50:08to unravel the mysteries of this prehistoric world.
00:50:11If we want to understand what has happened on the planet
00:50:13throughout history, we must go everywhere.
00:50:16We have to go to places like Antarctica.
00:50:22The fossils buried in the rock
00:50:25tell us about creatures
00:50:28who lived a hell on Earth to survive.
00:50:35Including the greatest extinction
00:50:38in the history of our planet.
00:50:40It is a lineage of survivors.
00:50:43One of the few lineages of terrestrial animals
00:50:47who managed to survive the great extinction of the Permian.
00:50:51The Listerosaurus managed to survive
00:50:54all the bad things that the Earth offered him.
00:50:59From the ashes of the great extinction
00:51:02emerges a 2.0 Earth
00:51:05in which little by little
00:51:07occupies the foreground
00:51:10a new dominant force.
00:51:13The dinosaurs.
00:51:16However, as the continents separated,
00:51:19how did they survive the polar conditions?
00:51:22And how did Antarctica transform
00:51:25into the frozen continent of today?
00:51:28The Ancestral Land.
00:51:31Dinosaurs of the Frozen Continent.
00:51:34The first dinosaurs
00:51:37appeared about 231 million years ago.
00:51:40During the Upper Triassic.
00:51:43However, their dominance
00:51:46was extended during the Jurassic period
00:51:4950 million years later.
00:51:54In the first expeditions to Antarctica,
00:51:57scientists were only able to find
00:52:00proto-mammals.
00:52:03Giant amphibians.
00:52:07And primitive reptiles.
00:52:14In 1986,
00:52:17scientists discovered, without knowing it,
00:52:20the first dinosaur on an Antarctic island.
00:52:23Later, it will be identified
00:52:26as a relative of the Ankylosaurus,
00:52:29with a claw-shaped tail.
00:52:31But the first discovery
00:52:34about the land took place four years later.
00:52:39Bill Hammer, an authority in Antarctica,
00:52:42knew immediately that it was something special.
00:52:45We go around a big rock
00:52:48and suddenly we find a femur of one meter long.
00:52:51A huge femur.
00:52:54I looked at it and David told me,
00:52:57what is this? And I told him, it has to be a dinosaur.
00:52:59And he told me, it is a dinosaur.
00:53:03A pteropod.
00:53:06A two-legged carnivore.
00:53:10One of the largest land carnivores of its time.
00:53:17They called it Cryolophosaurus.
00:53:21Which means,
00:53:24frozen crest lizard.
00:53:29If you find a dinosaur,
00:53:32you have to change your phone number.
00:53:35You call the New York Times,
00:53:38the National Public Radio, everyone will call you.
00:53:41Dinosaurs excite everyone.
00:53:44And the most surprising thing
00:53:47is that this dinosaur had some similarities
00:53:50with the Tyrannosaurus rex,
00:53:53although it had nothing to do with this great carnivore,
00:53:55which would not wander the earth
00:53:58until 124 million years later.
00:54:03It has a strange feature on its head,
00:54:06a bone plate in the shape of a crest
00:54:09from which it takes its name.
00:54:12Some dinosaurs had bone plates
00:54:15that served to defend themselves,
00:54:18but this one in particular does not seem to have any function.
00:54:21The Cryolophosaurus was first discovered
00:54:23near the Viedmoor Glacier,
00:54:26170 kilometers from the Sackleton expedition camp.
00:54:30It took many attempts
00:54:33to extract it from the frozen rocks.
00:54:36Finally, after three expeditions
00:54:39over 20 years, in 2011,
00:54:42Hammer and his team managed to recover
00:54:45the last pieces of the fossil's puzzle.
00:54:48The two leaders of the current joint expedition,
00:54:50Dr. Nate Smith and Dr. Pete McCovey,
00:54:53participated in that historical excavation.
00:54:56I'm Nate Smith, from the Field Museum.
00:54:59We have come to the Cryolophosaurus camp,
00:55:02and as you can see,
00:55:05the rock begins to have a more defined shape.
00:55:08The expedition to the Cryolophosaurus camp
00:55:11was very emotional for me,
00:55:14something very exciting,
00:55:17one of the most difficult moments of my career.
00:55:20There were about 30 bones in sight,
00:55:23and many of them seemed to be articulated,
00:55:26that is, they were still naturally joined.
00:55:29So in the rock we may have between a third
00:55:32and half of the animal.
00:55:35Instead of extracting the fossilized bones,
00:55:38the team cuts the entire block of rock
00:55:41in which the remains are embedded.
00:55:44Block by block they carry the precious rock
00:55:47to the helicopter that awaits them.
00:55:51We finally end up in this camp,
00:55:54a camp with which we began in 1990,
00:55:57and 20 years later,
00:56:00we have finally removed the last bones.
00:56:12This has been one of the most
00:56:15extraordinary experiences of my life.
00:56:17Coming to Antarctica has been amazing.
00:56:20This time it has been perhaps the best,
00:56:23although it has also been the most difficult.
00:56:26The discovery of a super-predator
00:56:29like the Cryolophosaurus leads us to the next question.
00:56:32What prey did this two-legged carnivore hunt?
00:56:35They would need a considerable meat diet
00:56:38to get ahead in the polar forests.
00:56:41In the same area of fossils
00:56:44that the Cryolophosaurus,
00:56:48now we know it as Glacialisaurus.
00:56:53The Glacialisaurus is a dinosaur
00:56:56that I baptized together with Diego Paul in 2007.
00:56:59We know that it was a very large animal.
00:57:02It is likely that it was the largest herbivore
00:57:05that lived in Antarctica during the lower Jurassic.
00:57:08This herbivorous dinosaur
00:57:117 meters long and 5 tons was very fast.
00:57:18When these lower Jurassic dinosaurs
00:57:21erupted on stage,
00:57:24the land they stepped on
00:57:27was also in motion.
00:57:30The supercontinent of the earth, Pangea,
00:57:33separated to form smaller earth masses,
00:57:36Eurasia and Gondwana.
00:57:39And the ocean that separated them
00:57:42was the trigger for the eruption.
00:57:44The Mesozoic Era.
00:57:47If we go back in time to the Mesozoic,
00:57:50to the time of the dinosaurs,
00:57:53Antarctica was still connected
00:57:56to the other southern continents and Gondwana
00:57:59and had no ice at all.
00:58:02It had a warmer climate
00:58:05where animals and plants could thrive.
00:58:08The Mesozoic was a time
00:58:11when there was no ice,
00:58:14and there was no water.
00:58:21Glacialisaurus had to be fast,
00:58:24since it was one of the main prey
00:58:27of the cryolophosaurus.
00:58:30Hidden among the Jurassic forests of Antarctica,
00:58:33this solitary hunter
00:58:36would stalk the herds of Glacialisaurus,
00:58:39as the great cats do today
00:58:41and watch the herbivores in the savannah.
00:58:52For these great carnivores,
00:58:55a long-necked herbivore
00:58:58could feed them for days.
00:59:12But first they had to be caught.
00:59:32This 7-meter-long theropod
00:59:35ran at almost 40 kilometers per hour.
00:59:41But sometimes evolution gives the prey
00:59:44an advantage in a race like this one.
00:59:48The cryolophosaurus cannot maintain
00:59:51its maximum speed for a long time.
00:59:54It will need a stroke of luck.
01:00:04A herd of Glacialisaurus
01:00:07facing it makes it think twice.
01:00:12It is not easy to catch it.
01:00:25Because of its mysterious crest,
01:00:28it is sometimes nicknamed Elvisaurus.
01:00:32But what was it for?
01:00:35Maybe to attract a couple.
01:00:41To relieve the group,
01:00:44the male has smelled the trace of a close female.
01:01:03It is even possible that the cryolophosaurus
01:01:06had striking colors on its head
01:01:08to attract its mates.
01:01:11As casuaries do today.
01:01:15My colleague Pete Makovicki
01:01:18has done extensive research
01:01:21on the crests and colors of modern birds.
01:01:24One of his findings is that
01:01:27it is often not the crest itself
01:01:30that gives that elaborated color,
01:01:33but the skin around the eye,
01:01:35Until now, no remains of cryolophosaurus
01:01:38have been found anywhere on Earth.
01:01:43It probably dominated the period
01:01:46of the lower Jurassic in Antarctica.
01:01:49And as the period advanced,
01:01:52the dinosaurs were increasing in size
01:01:55all over the world,
01:01:58due to an explosion of plant life
01:02:01that brought the new global warming.
01:02:05The colossi of the Jurassic world.
01:02:08The sauropods.
01:02:11There were numerous species
01:02:14of these giant herbivores.
01:02:17But even among this group of huge creatures
01:02:20there was a species that stood out
01:02:23above all the others.
01:02:26The culmination of this group of sauropodomorphic dinosaurs
01:02:29are the titanosaurs.
01:02:32They are the largest terrestrial animals
01:02:35in the world.
01:02:38The titanosaurs were colossal.
01:02:4336 meters long
01:02:46and a weight of approximately 60 tons.
01:02:52The equivalent of a dozen elephants.
01:02:57Adults did not have natural predators.
01:03:00Only a natural disaster could stop them.
01:03:08The titanosaurs are a mystery of biology.
01:03:11They are nothing like any other animal
01:03:14that has ever lived on Earth.
01:03:18These colossal vegetarian beasts
01:03:21dominated the Jurassic period
01:03:24and later the Cretaceous period
01:03:26except for Antarctica.
01:03:29Or so the scientists thought.
01:03:36In 2011, a fossil was unearthed
01:03:39on the island of James Ross in Antarctica.
01:03:42Which showed that these giants
01:03:45of the world of dinosaurs
01:03:48did visit the southernmost earth mass.
01:03:51But how could a bigger animal
01:03:53exist on Earth than a blue whale?
01:03:56You'd think it's impossible
01:03:59for those gigantic bodies to exist on Earth.
01:04:02They are not like the whales
01:04:05that float in the water in the absence of gravity.
01:04:08They walked on solid ground.
01:04:11Therefore, the sauropods made
01:04:14certain anatomical adaptations
01:04:17that helped them survive
01:04:20in those terrestrial environments.
01:04:23Their spine was so long
01:04:26that they have been called
01:04:29a walking spine.
01:04:33Their incredibly long necks
01:04:36were full of airbags
01:04:39like modern birds,
01:04:42which helped them breathe
01:04:45and lighten the load of their huge skeletons.
01:04:48At the end of their long necks
01:04:50they had a tiny brain
01:04:53and teeth adapted to eat plants.
01:04:58Their heart, which weighed several hundred kilos,
01:05:01was the size of a man.
01:05:04Each of their beats
01:05:07pumped 90 liters of blood through the arteries.
01:05:12So trying to understand
01:05:15how these organisms lived for hundreds of millions of years
01:05:17with this size
01:05:20is one of the greatest mysteries of paleontology.
01:05:23Perhaps the titanosaurs competed with each other
01:05:26as the giraffes do today.
01:05:33The competition to be the dominant male or alpha
01:05:36must have been brutal.
01:05:47Many questions in the research
01:05:50carried out by paleontologists
01:05:53when joining the puzzle of fossil remains
01:05:56with millions of years of antiquity.
01:06:09It is known that these giants
01:06:12prospered all over the world
01:06:14in the exuberant tropical forests of the Cretaceous.
01:06:25There have been indications
01:06:28that at least the titanosaurs
01:06:31could consider Antarctica a kind of route of passage.
01:06:36Although the earliest titanosaur fossils
01:06:39were found in South America,
01:06:41in recent years
01:06:44some species have been extracted on rocks
01:06:47on the other side of the world,
01:06:50in Australia.
01:06:53Fossils similar to their
01:06:56older South American equivalents.
01:06:59If we look at some of these dinosaurs,
01:07:02such as the Argentine titanosaurs,
01:07:05Antarctica and Australia,
01:07:08we can see that they were somehow related to each other.
01:07:11Although it goes back to when all continents
01:07:14were part of Gondwana.
01:07:18The fact that they were discovered in Australia
01:07:21implies that these gigantic dinosaurs
01:07:24had to cross the polar forests.
01:07:27Ancient Antarctica served as a land bridge,
01:07:30which allowed the titanosaurs
01:07:33to reach Australia from South America,
01:07:36where they were abundant in number.
01:07:38It makes sense, since the southern continents
01:07:41were connected at that time.
01:07:44Those titanosaurs had to be able to cross Antarctica
01:07:47to reach other regions.
01:07:56In Antarctica,
01:07:59the giant titanosaurs would find
01:08:02a somewhat colder climate,
01:08:05but without ice and covered with forests.
01:08:08It was an epic journey to Australia.
01:08:15No predator could stop
01:08:18these colossal forces of nature.
01:08:21Being giant is a good strategy
01:08:24if you want nothing to eat you.
01:08:27In modern ecosystems, such as sub-Saharan Africa,
01:08:30we see that elephants don't have natural predators
01:08:33when they are adults.
01:08:35If you can be big, why not be it?
01:08:38It's the best strategy not to be someone else's food.
01:08:46Today's titans, such as elephants,
01:08:49could never reach that size
01:08:52because they breed their young in the uterus.
01:08:55The titanosaurs did not have this limitation.
01:09:01They were oviparous.
01:09:05Herds of females laid thousands of eggs in a group,
01:09:08up to 40 at a time,
01:09:11in their shallow nests.
01:09:21But their young were not so invincible.
01:09:25They were extraordinarily vulnerable
01:09:28to predators.
01:09:31Probably the highest mortality levels
01:09:33in the titanosaurs
01:09:36were among the newborns,
01:09:39which is when they would be most vulnerable to predators.
01:09:42Abandoned to their fate by adults,
01:09:45these young needed their own evolutionary lifeguard.
01:09:50It was difficult to live being small
01:09:53in the Jurassic or the Cretaceous,
01:09:56with all those huge dinosaurs roaming around.
01:09:59So one of their strategies was a very fast growth rate.
01:10:01The faster you grow,
01:10:04the more likely you are to survive.
01:10:07However, trying to calculate
01:10:10how fast these dinosaurs grew
01:10:13from adult specimens is difficult,
01:10:16if not impossible.
01:10:19Until Dr. Rogers found a series of non-catalogued
01:10:22fossils in 2012.
01:10:26I was searching for crocodile bones
01:10:28and turtle bones in a collection
01:10:31and when I did, I found small sauropod bones.
01:10:36And at the end of the day I realized
01:10:39that I had a large part of the skeleton,
01:10:42bones belonging to a single small sauropod,
01:10:45which turned out to be the smallest we have
01:10:48after hatching from the egg.
01:10:51I knew immediately that it was very important
01:10:54that we hadn't found tiny fossils of young animals.
01:10:58To locate those small bones,
01:11:01I had an idea of what those tiny animals would look like.
01:11:06If you search in a museum's collection,
01:11:09just by opening the drawers,
01:11:12there is always something new to discover.
01:11:15Some important discoveries in paleontology
01:11:18are made because someone adopts a different approach
01:11:21to something that someone else picked up
01:11:2420 or 100 years ago.
01:11:26These bones made it clear
01:11:29that the titanosaurids had very early offspring.
01:11:32Their little ones were almost independent
01:11:35as soon as they came out of the egg.
01:11:38Now we believe that by breaking the shell,
01:11:41these young ones were quite able to fix them on their own.
01:11:44The question is, how long did it take
01:11:47for them to become giants?
01:11:50By increasing the microscope to very fine
01:11:53transversal sections of the fossils,
01:11:56and the bloodstream,
01:11:59and determining the rate of growth.
01:12:02When you take a look at a section of a dinosaur bone like this,
01:12:05we see a lot of little circles all over the bone,
01:12:08which are the points where the blood vessels
01:12:11would come in and out of the bone.
01:12:14The more blood vessels it had,
01:12:17the more directions it went, the faster the animal grew.
01:12:20These cells tell us that it grew very fast.
01:12:23All the blood vessels distributed by the bone
01:12:26were in the bloodstream as well.
01:12:32The mortality rate was high among young titanosaurids,
01:12:36but their rapid growth gave them a chance.
01:12:41As a comparison,
01:12:44a human baby doubles in size every five months,
01:12:47while the titanosaurids doubled in size every five days.
01:12:50At the time of their first year,
01:12:53they weighed from 20 kilos to 1,600.
01:13:00This is the femur of a three-month-old titanosaur,
01:13:03next to the femur of a 20-year-old titanosaur.
01:13:06Observing the difference in size,
01:13:09we realize how fast this little animal had to grow
01:13:12to reach that size in just 20 years.
01:13:15The fact that the Antarctic continent
01:13:17was connected to other terrestrial masses at that time
01:13:20made it a gateway for the migration of animals
01:13:23as large as the titanosaurids.
01:13:26But the Antarctic was different.
01:13:29Despite its temperate climate
01:13:32and its endless polar summers,
01:13:35they suddenly transformed into very long winters
01:13:38where darkness reigned.
01:13:41One of the eternal mysteries of Antarctic paleontology
01:13:44is to know what these animals were like.
01:13:47These animals experienced several months
01:13:50of perpetual light in summer
01:13:53and several months of perpetual darkness in winter.
01:13:56During this period,
01:13:59plant life entered a state of inactivity
01:14:02and the highest levels of carbon dioxide
01:14:05helped plants survive
01:14:08during the long months without sun.
01:14:11Despite the absence of photosynthesis during the winters,
01:14:14somehow the vegetation managed to survive
01:14:17in that environment.
01:14:20But how did the dinosaurs survive
01:14:23in the middle of polar darkness?
01:14:32It is not only because the sun does not cross
01:14:35the Antarctic darkness for four months,
01:14:38but also because the temperature drops to temperatures below zero.
01:14:43It is difficult to imagine
01:14:45what the ecosystem was like for the dinosaurs.
01:14:48Here the dinosaurs lived in the middle of total darkness
01:14:51for several months in winter
01:14:54and at temperatures below zero.
01:14:57Some days it was less cold, yes,
01:15:00but in general it must have been a very complicated environment
01:15:03for any animal that lived in it.
01:15:08In the Transantarctic mountains,
01:15:11the team is still looking for some clue
01:15:13to shed light on this enigma.
01:15:16Paleobotanists are lucky
01:15:19in the search for fossils in this expedition.
01:15:22Ok, I think there is something.
01:15:25Yes, there is something here.
01:15:28Wonderful, wonderful, yes.
01:15:31However, it is never easy for paleontologists
01:15:34to extract fossils from the frozen rock.
01:15:37One of the possible keys to solving
01:15:40the mystery of survival in polar conditions
01:15:43lies in the depths of the ancient rocks
01:15:46of the former neighboring Antarctica, Australia.
01:15:49During the Cretaceous period,
01:15:52100 million years ago,
01:15:55the southeast of Australia was within the polar region.
01:15:58Here, a small dinosaur could adapt
01:16:01to the sunless winters in a singular way.
01:16:04The Lialinasaura was a small dinosaur
01:16:07from which fragments were found
01:16:10in a place called the Dinosaur Gorge.
01:16:13It is named after the daughter of Patricia Vickerson Rich
01:16:16and Tom Rich, Lialin.
01:16:21The Lialinasaura was a herbivorous dinosaur
01:16:24the size of a turkey,
01:16:27and it is likely that it permanently resided
01:16:30in the polar forests.
01:16:33Unlike other larger dinosaurs,
01:16:36the Lialinasaura was not big enough
01:16:39to travel thousands of kilometers
01:16:41as many animals and birds do today
01:16:44to avoid the current winters.
01:16:47It was too small to migrate,
01:16:50so it takes a lot of energy, a lot of food
01:16:53to travel thousands of kilometers,
01:16:56and if you also have short legs,
01:16:59it takes a lot more effort to do that.
01:17:02In the fossil of the small Lialinasaura,
01:17:05scientists found a possible indication
01:17:08of how dinosaurs evolved
01:17:11in large cavities,
01:17:14that is, the cavities in which the eyes used to be.
01:17:17But towards the back of the skull,
01:17:20the sand filled the area where the optical lobe
01:17:23would have been found,
01:17:26and it seems that it was also relatively large in the skull too.
01:17:29So, these two clues point to the possibility
01:17:32that the Lialinasaura could see well in the dark.
01:17:35In the case of nocturnal animals,
01:17:38their large eyes take full advantage
01:17:41of the little light available.
01:17:44In turn, the larger optical lobes
01:17:47are able to process the visual information
01:17:50they perceive more effectively.
01:17:53However, science is not clear
01:17:56about this specimen of Lialinasaura.
01:17:59We know that there are great variations
01:18:01in the proportions of the organs of animals,
01:18:04such as the eyes,
01:18:07and we know that,
01:18:10both among modern birds and among dinosaurs,
01:18:13smaller animals usually have
01:18:16proportionally larger eyes.
01:18:19Having a good night vision
01:18:22must have been important when hunting,
01:18:25but even so, they would need other strategies
01:18:28to face life during four months of cold darkness.
01:18:31This is the case with polar bears.
01:18:34The fossil expert Anthony Martin
01:18:37found a possible answer just a few kilometers away
01:18:40from the place where the Lialinasaura was discovered.
01:18:43I am in Victoria, Australia,
01:18:46in Ollies Creek,
01:18:49observing some of the cretaceous rocks
01:18:52that are in this area.
01:18:55In that cliff I saw a tubular structure
01:18:58that descended, expanded,
01:19:01and I remember having a feeling inside
01:19:04that said to me,
01:19:07wait, that looks familiar.
01:19:10It has a similar structure above,
01:19:13full of sand, and it presents a shape
01:19:16somewhat in a spiral.
01:19:19As we move to the right,
01:19:22we see that there is a third structure
01:19:25that is similar, but that is a little more collapsed.
01:19:28And that moment is when I thought
01:19:31that polar bears can use burrows
01:19:34to take refuge from the heat
01:19:37or from the extreme cold,
01:19:40and the three cave structures in Australia
01:19:43had the right size
01:19:46for a small dinosaur
01:19:49that trusted to be able to protect itself
01:19:52from a polar winter.
01:19:55That made me wonder
01:19:58what kind of animals could have lived there,
01:20:01the small-sized dinosaurs
01:20:04that lived in the area at that time.
01:20:07It is possible that the creatures
01:20:10used this adaptation in the different eras
01:20:13to survive in Antarctica,
01:20:16even during the most massive extinction
01:20:19in the history of the Earth,
01:20:22recorded 250 million years ago.
01:20:25But is there any other clue in Antarctica?
01:20:28The answer may come
01:20:31from an existing lystrosaur.
01:20:34A reptile similar to a mammal
01:20:37that survived the great mortality
01:20:40that killed 90% of the animals
01:20:43at the end of the Permian period.
01:20:46Back to the Sackleton Glacier,
01:20:49Chris Sider and Megan Whitney
01:20:52are making great progress
01:20:55in the preparation of a fossil
01:20:57of a lystrosaur
01:21:00that was in a totally vertical face of a cliff.
01:21:03This is something new for me.
01:21:06I have never done anything on such a steep wall.
01:21:09It is not usual to find fossils in such a place.
01:21:12It was a coincidence that this one stood out a bit,
01:21:15but we had to extract it from the vertical wall,
01:21:18and for that we had to surround it.
01:21:21We ended up using the drilling hammer,
01:21:24making many holes
01:21:27and doing all kinds of things.
01:21:30Yes, I see the crack.
01:21:33Yes.
01:21:36There it is.
01:21:39Just where we wanted.
01:21:42Well, we have extracted...
01:21:45The first fragment.
01:21:48The first fragment.
01:21:51This goes here, but it was the easy fragment.
01:21:54What comes now will be much more complicated, I think.
01:21:57Fossils of lystrosaur
01:22:00from polar regions such as Antarctica,
01:22:03with others from regions such as South Africa,
01:22:06a surprising possibility arises.
01:22:09A transversal section of its small fangs
01:22:12shows a variation in the speed of growth,
01:22:15the first clue about how they could have survived
01:22:18the polar winter.
01:22:21Chris Sider and Megan Whitney
01:22:24have studied in detail the growth lines
01:22:27of Antarctic animals,
01:22:30as in some of the fossils of South Africa,
01:22:33and what they discovered is that in the first ones
01:22:36certain periods are observed in which very close lines are seen,
01:22:39which correspond to difficult periods in the environment,
01:22:42when perhaps the animal would slow down part of its growth,
01:22:45and that it is compatible with the seasonal lethargy,
01:22:48moments in which these animals experience
01:22:51a lower metabolic activity,
01:22:54possibly during the Antarctic winters.
01:22:57It was the lystrosaur after this great extinction
01:23:00that ended with 95% of all living beings on Earth.
01:23:03We have found that they survived,
01:23:06and I do not think it was by chance.
01:23:09Animals still resort to lethargy today.
01:23:12In its most extreme phase is hibernation,
01:23:15which consists of the reduction of metabolism,
01:23:18body temperature and activity for weeks.
01:23:20If there are signs of some form of lethargy
01:23:23in the fangs of the ancestor mammal, the lystrosaur,
01:23:26animals could resort to this adaptation
01:23:29to survive the Antarctic conditions
01:23:32and even to massive extinctions hundreds of millions of years.
01:23:35Despite the polar nights,
01:23:38life has taken the hand of creativity,
01:23:41and it is not surprising that the animals
01:23:44have been able to survive
01:23:46despite the polar nights.
01:23:49Life has taken the hand of creativity to survive,
01:23:52waiting for the good times to return
01:23:55in the long summer months.
01:24:00More than 180 million years after the Great Mortality,
01:24:03dinosaurs continued to dominate our planet.
01:24:09But suddenly, 66 million years ago,
01:24:12a rock from the solar system
01:24:14swung towards the atmosphere of the Earth,
01:24:17something that even the dinosaurs could not adapt.
01:24:21An asteroid of 15 kilometers in diameter
01:24:24fell on the Yucatan Peninsula in Mexico.
01:24:33The effects it caused
01:24:36greatly contributed to the extinction of dinosaurs.
01:24:45The evidence is abundant
01:24:48in the geological record of our planet
01:24:51known as the Cretaceous-Tertiary Limit.
01:24:55The enriched layer of iridium
01:24:58is one of the key evidence
01:25:01that supports the hypothesis of the impact of an asteroid,
01:25:04since it is found at the same time
01:25:07in many regions of the world.
01:25:10The dust that raised the impact of the asteroid
01:25:12eclipsed the sun,
01:25:15so the ecosystem collapsed almost completely.
01:25:1875% of life forms disappeared,
01:25:21including all animals
01:25:24weighing more than 25 kilograms,
01:25:27even in the polar region of Antarctica.
01:25:32But who took their place?
01:25:38The animals that survived the extinction
01:25:40are the ancestors of reptiles,
01:25:43amphibians, mammals,
01:25:46and fish of today.
01:25:49In addition, a strange species of bird
01:25:52would arrive in Antarctica,
01:25:55the penguin.
01:25:58A halo of mystery envelops its extravagant evolution
01:26:01since they were discovered.
01:26:06Numerous species of penguin
01:26:08live in the coastal margins and islands of Antarctica.
01:26:12But only the emperor penguin
01:26:15and the deadelia live here permanently.
01:26:18They feed in the ocean and nest on land
01:26:21or in sea ice.
01:26:24But where and how did they evolve
01:26:27and what links do they have with the end of the dinosaur era?
01:26:30Can the predecessors of the modern penguin
01:26:33give us some clue about what happened
01:26:35after the disappearance of the dinosaurs?
01:26:38The fossil record of birds
01:26:41is considerably irregular and scarce,
01:26:44since most birds have very light skeletons
01:26:47and delicate bones.
01:26:50The case of penguins is very different
01:26:53since having thicker bones,
01:26:56we have a much better fossil record
01:26:59of them than of other bird groups.
01:27:02The first fossil was discovered in 1980.
01:27:05At the time, it was unknown.
01:27:08It was going to become the oldest penguin fossil
01:27:11that has been discovered.
01:27:14It lived between 60 and 62 million years ago,
01:27:17not long after the extinction of the dinosaurs.
01:27:23This specimen, known as guaymanu,
01:27:26which means aquatic bird in Maori,
01:27:29was a kind of hybrid
01:27:32between a sea bird and a modern penguin
01:27:35that looked like a modern bird
01:27:38from New Zealand.
01:27:44The guaymanu is a penguin,
01:27:47but it has many characteristics
01:27:50very similar to other groups of modern marine birds,
01:27:53such as the cormorants,
01:27:56that are distributed all over the world.
01:27:59The guaymanu was a primitive penguin
01:28:02and it is unlikely that it had the ability to fly.
01:28:05It was known as a non-flying bird,
01:28:08but it used the smallest wings
01:28:11to propel itself through the water.
01:28:14The first time you see a penguin,
01:28:17it is not easy to forget that they are birds,
01:28:20but they are.
01:28:23They have a beak, they lay eggs,
01:28:26they have feathers.
01:28:29If we look at all aspects of their physiology
01:28:32and their behavior,
01:28:35they are very similar to the guaymanu
01:28:38that we know today.
01:28:41They are closely related to the procelariiformes,
01:28:44which are the birds of tubular beaks
01:28:47such as the petreles, albatros, pardelas, etc.
01:28:50In the end, one of those ancestors
01:28:53adapts by staying longer in the water,
01:28:56trying to capture its food by immersing more
01:28:59and swimming for longer.
01:29:02Nowadays, penguins have adapted
01:29:05to the predators of the ocean,
01:29:08living and building their nests on land.
01:29:11They only go into the sea to fish.
01:29:14But the evidence has revealed
01:29:17something even more surprising.
01:29:20The fossil record shows
01:29:23that after the guaymanu,
01:29:26even larger versions of penguins were discovered
01:29:29in Antarctica and several species also in New Zealand.
01:29:35Some of these giant species
01:29:38were up to 30 cm higher
01:29:41and they doubled the weight of the largest penguin
01:29:44we have today, the emperor.
01:29:49But why did such a large penguin live then
01:29:52and not now?
01:29:56The asteroid that fell on Earth
01:29:5966 million years ago
01:30:02not only killed terrestrial animals,
01:30:05but also killed the vast majority
01:30:08of the great marine predators,
01:30:11which opened a niche in the ecosystem for the penguin.
01:30:14Let's imagine an ocean probably devoid
01:30:17of a large number of primary predators
01:30:20and, on the other hand, a few marine birds
01:30:23that were beginning to spread around the world
01:30:26and that realize that there are all these open niches,
01:30:29empty spaces that were waiting
01:30:32for a species to evolve to exploit its resources.
01:30:35After the death of the terrestrial dinosaurs
01:30:38new and strange creatures emerged in Antarctica
01:30:41and the seas began to fill again
01:30:44with marine life.
01:30:47However, the giant penguins
01:30:50and flying creatures of Antarctica and New Zealand
01:30:53have contributed to shake the greatest mystery
01:30:56of the current paleontology.
01:30:59Are they the true descendants of the dinosaurs?
01:31:06Did their lineage disappear
01:31:09to which it had also gone for 165 million years
01:31:12with that catastrophe?
01:31:15Or a part of the dinosaurs
01:31:18managed to survive to us
01:31:21in the form of birds?
01:31:26The first penguins point out
01:31:29that their flying relatives already existed
01:31:32before the fall of the asteroid.
01:31:35Now we know that some dinosaurs
01:31:38had feathers
01:31:41and laid eggs like birds.
01:31:44A mysterious hybrid fossil named Archaeopteryx
01:31:47discovered on the other side of the world
01:31:50gave us another clue.
01:31:53Archaeopteryx played a crucial role
01:31:56in establishing the link between
01:31:59modern dinosaurs and birds.
01:32:02It is clear that it was a dinosaur with feathers
01:32:05and it showed many characteristics
01:32:08that still retained much of the anatomy of dinosaurs,
01:32:11but at the same time it already had many of the features
01:32:14that we find in modern birds.
01:32:17However, the Archaeopteryx
01:32:20of 150 million years of antiquity
01:32:23is nothing more than a test.
01:32:26The discovery of another fossil
01:32:29would bring us a lost link later.
01:32:32A paleontologist who worked
01:32:35with the Archaeopteryx started with this fossil.
01:32:39As it happens with many discoveries,
01:32:42it was cornered and unidentified
01:32:45for two decades.
01:32:48But a casual review
01:32:51left scientists amazed.
01:32:54The fossilized skeleton
01:32:57dated approximately from the time
01:33:00of the impact of the asteroid.
01:33:02It had many different features
01:33:05in common with modern ducks and geese.
01:33:08It was baptized as Begabis.
01:33:11It could be like a primitive flying duck.
01:33:18It is potentially the ancestor
01:33:21of ducks and geese.
01:33:26And the most impressive thing,
01:33:29it had the oldest known example
01:33:32of a caviar, a resonance box
01:33:35like modern aquatic birds have.
01:33:38It is an early ancestor
01:33:41that presents much of the features
01:33:44that were developing in its group,
01:33:47like the syringe.
01:33:50Having such an ancient bird fossil
01:33:53of the Cretaceous, well settled
01:33:56in the genealogical tree of birds,
01:33:59indicates that the deep diversification
01:34:02took place in the Late Cretaceous,
01:34:05not older.
01:34:08Thus, some avian dinosaurs
01:34:11survived the Great Extinction
01:34:14to become birds,
01:34:17while all non-avian dinosaurs
01:34:20disappeared.
01:34:23When creatures like the giant penguin
01:34:26took its place,
01:34:29and modern mammals gave roots,
01:34:32it created a forest system
01:34:35during the next 31 million years.
01:34:38However,
01:34:41approximately 35 million years ago,
01:34:44when the southern continents separated more,
01:34:47Antarctica was totally isolated
01:34:50in the confines of the Earth,
01:34:53which brought devastating consequences.
01:34:56During the Great Extinction of the Cretaceous,
01:34:59Antarctica was a very different place.
01:35:02One of the main factors
01:35:05is the separation of the southern continents.
01:35:08We are not talking about something instantaneous,
01:35:11but a gradual process,
01:35:14and we witness the creation of a circumpolar current.
01:35:17This is the kind of events that are key
01:35:20to the change of climate in Antarctica,
01:35:23and that allows ice to be formed again.
01:35:26Antarctica is surrounded
01:35:29by a sea of low temperatures
01:35:33On land,
01:35:36temperatures plummet.
01:35:39Snow in winter melts in spring,
01:35:42and then in summer.
01:35:45When the layers of ice return,
01:35:48the terrestrial mammals disappear from Antarctica.
01:35:53Over millions of years,
01:35:56layers and layers of ice accumulate,
01:35:59and 15 million years ago,
01:36:02they would have returned.
01:36:08Today,
01:36:11these layers reach a thickness of up to 5 kilometers.
01:36:14Any trace of prehistoric animals
01:36:17remained hidden under an ice mantle,
01:36:20until at the beginning of the 20th century,
01:36:23some explorers found fossilized leaves.
01:36:25A century later,
01:36:28the most recent expedition comes to an end.
01:36:37In the base camp of Shackleton,
01:36:40scientists catalog their findings.
01:36:43Boxes and boxes of fossils
01:36:46embedded in rocks,
01:36:49waiting to be extracted in the laboratory.
01:36:52A great reason to celebrate
01:36:55after six weeks living
01:36:58in one of the most isolated places on Earth.
01:37:05First, a brief transfer to McMurdo,
01:37:08and then a long flight back
01:37:11to New Zealand and beyond.
01:37:21But when they return to the laboratory,
01:37:23that's when the real work begins.
01:37:26The cryolophosaurus.
01:37:29These dorsals came out perfectly.
01:37:32To reveal the mysteries of the lost world
01:37:35of the dinosaurs of Antarctica.
01:37:38It's kind of like getting back to Christmas,
01:37:41when you have everything in the laboratory
01:37:44and you start opening the boxes and preparing everything.
01:37:47It's like rediscovering everything again.
01:37:50Wow, look at this, how well preserved.
01:37:53It's a thousand kilometers from here,
01:37:56except where the ice was, the state of conservation is extraordinary.
01:37:59The bone is phenomenal.
01:38:02We found better fossils and more complete ones,
01:38:05remains that may belong to new species.
01:38:08For us, Antarctica is nothing more than another piece
01:38:11of the puzzle to understand the evolution of the climate
01:38:14and how it influenced plants and animals at that time.
01:38:17There are still many things to discover.
01:38:20Every place we go has its own story.
01:38:23Little by little, the secrets of Antarctica are revealed.
01:38:29The paleontology that comes from Antarctica
01:38:32has an incalculable value because it serves us
01:38:35to unravel a piece of the puzzle of the history of life.
01:38:38How was life in those polar environments
01:38:41for a very long period of time?
01:38:46But it is clear that while the human being continues to explore,
01:38:50this is not the end of the history of life.
01:38:53It is the beginning of an ancestral life in Antarctica.
01:38:57With each new discovery,
01:39:00the dinosaurs of the frozen continent reappear.