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00:00To be continued...
00:30where do birds come from and who were their ancestors for a long time these
00:54questions have remained unanswered their family tree stopped abruptly at the oldest known species
01:02a fossil found in 19th century Germany Archaeopteryx whose name comes from the Greek for ancient wing
01:16but since 1996 thousands of animals unearthed in China have shed new light on the origin
01:24of birds this abundance of the discoveries proves that most dinosaurs were not covered
01:40in scales but clad in feathers some of these feathered dragons could even fly
01:54the extent of the Asian jigsaw puzzle is so vast that it ties modern-day birds to remarkable
02:00distant cousins and suggests a multitude of relatives during the Jurassic period between 200 and 145
02:13million years ago the supercontinent Pangaea opened up creating separate land masses at the edges of this
02:22world China and Siberia formed a huge peninsula with a temperate climate similar to that of modern Europe
02:44the breakup of the continents was accompanied by volcanic eruptions particularly in China
02:51a paradise in waiting inhabited by strange creatures like anchiones meaning near bird this little dinosaur is completely covered in feathers
03:14the size of the size of the size of a modern-day pigeon anchiones is a long-lossed relation
03:25the descendants of this lightweight dinosaur survived better than other large theropods the group that includes all carnivorous dinosaurs
03:36including guanlongs they are efficient hunters three meters long weighing 50 kilograms
03:59to escape anchiones was capable of short gliding flights while its pursuer was firmly stuck on the ground
04:16and yet guanlong also had feathers
04:19and yet guanlong also had feathers
04:33And yet, Guanlong also had feathers.
04:45What were they used for?
05:03Erupting volcanoes spewing fine ash and noxious gases froze a moment of Jurassic life for eternity, helping us answer some of these questions.
05:33This dinosaur paradise has become the feathered dinosaur's Pompeii.
05:40A huge range of new species has recently been discovered in one of China's many construction sites.
05:53Over the last two decades, in the Liaoning region, paleontologists have collected thousands of specimens, hidden for many years.
06:03These magnificent fossils are in a state of almost perfect preservation, thanks to the mixture of extremely fine clay and volcanic ash sediment.
06:21And those are volcanic eruptions, killed the animal directly and buried their bodies.
06:30So that's why we have some beautiful skeleton and I include soft tissue preserved.
06:34So that's why we come here.
06:37Paleontologist Xu Xing and his colleagues from around the world can trace the chaotic history of flight and feathers in these rocks.
06:47The feather preservation is really amazing.
06:51Like detectives, they examine the clues to understand what feathers were used for.
06:56And discover how some dinosaurs from the theropod family turned, over the course of millions of years, into birds.
07:11The first piece of evidence in their inquiry was discovered at the end of the 19th century in Germany.
07:29Towards the end of the Jurassic period, Europe was partly submerged under a shallow body of water called the Tethys Sea.
07:39About 150 million years ago, Germany was dotted with tropical islands.
07:50Pterosaurs, the first flying vertebrates, have dominated the skies for 80 million years.
08:05This is German Odactylis, one of 150 species of pterosaurs discovered.
08:12These flying reptiles are not dinosaurs.
08:18A fine skin stretches over their elongated fingers to create leathery wings.
08:23This membrane, along with powerful muscles and hollow bones, makes them masters of the skies.
08:31But the pterosaurs' aerial supremacy is about to be challenged by the very first birds.
08:58Such as Archaeopteryx.
09:02A primitive bird, whose claws at the ends of its wings, raise suspicions amongst 19th century paleontologists.
09:16Its fossils were found around the modern German town of Sonhofen, a tropical archipelago during the late Jurassic period.
09:34Some islands harbored salty lagoons, where dying animals avoided scavengers.
09:39And were buried by soft mud that preserved them in minute detail.
09:50Eberhard Frey, commonly known as Dino Frey, is the resident expert.
10:05This is the famous Solnhofen laminated limestone.
10:10And you can actually see the sediments stapled up like the leaves of a book.
10:15And inside the leaves of this rocky book, this is where Archaeopteryx was found together with many other fossils.
10:23And it's a speciality of this rock that it is very, very, very fine grained.
10:30And inside this mud, fossils are preserved like in a tin.
10:35And this is why this entire area is so valuable as a window in Jurassic times.
10:42The locals use these stones to tile their houses.
10:47In the process, uncovering highly prized treasures in the history of paleontology.
10:52In 1868, faced with the Archaeopteryx, British biologist Thomas Henry Huxley asserted that this was a transitional fossil between reptiles and birds.
11:19A friend of Darwin and an ardent defender of the theory of evolution, Huxley was an expert anatomist.
11:48Capable of skilled fossil analysis.
11:51Until the year 1861, before Archaeopteryx was discovered, the only creatures that were known to have feathers were the birds.
11:59So it was apparent that this is a fossil bird.
12:02And Thomas Huxley looked at it very closely and he discovered signs that this bird could also be a dinosaur, actually a carnivorous dinosaur.
12:13And actually shares characters of the two, making it a missing link between dinosaurs and birds.
12:20That was a sensation at the time.
12:22The Darwinian idea of natural selection is therefore very recent.
12:35Huxley had the insight to see that Archaeopteryx's teeth, clawed wings and bony tail meant that it had similarities with comsognathous dinosaurs, predatory relations of the velociraptors.
12:58Archaeopteryx was certainly no acrobat, but it had feathers.
13:17And it could fly.
13:25Its collarbones had already fused together, a vital step enabling the wings to flap efficiently and gain altitude, allowing it to hunt and nest in trees.
13:37Throughout the 20th and 21st centuries, more Archaeopteryx fossils were unearthed in Germany.
14:06This is specimen number 11.
14:17It's the latest specimen and it came to light in the year 2011.
14:21And despite its fragmentary, it's not completely preserved because the skull is missing,
14:27it still shows us some features which were previously unknown.
14:31One of them is that the tail end shows a V-shaped feather configuration.
14:36And the second is that you can see in this specimen the extent of the feather travers along the legs.
14:43The feathers on its feet are intriguing since modern birds no longer show this characteristic.
14:58Is this an exception?
15:00What is sure is that this feature has not been selected by evolution.
15:05Just like this giant marine reptile, a Leopleurodon.
15:11Washed up on the shores of the lagoon, it is a godsend for Archaeopteryx.
15:26The flies, attracted by the carcass, provide a hearty meal for this insect eater.
15:39But being out in the open is dangerous for Archaeopteryx.
15:43An opportunistic Germanodactylist sees the prospect of a protein rich meal.
15:58And doesn't appreciate the competition.
16:13Once the mightiest creatures in the skies, pterosaurs became extinct by the end of the Cretaceous period, 65 million years ago.
16:32While Archaeopteryx's descendants grew in number.
16:36Bogged down at the bottom of the Sonhofen Lagoon, this remarkable fossil launched the debate on the relationship between birds and dinosaurs.
16:47But with insufficient proof, this theory was shelled for more than a hundred years.
16:59Until new evidence came to light at the end of the 20th century in China.
17:06In 1993, Lianning, a huge fossil deposit was found dating from the Cretaceous period, 125 million years ago.
17:25This region, formerly known as Manchuria, comprises fertile farmland with fields of corn and pasture.
17:37Farmers were the first to uncover fossils inadvertently.
17:42In Sihatun, at the foot of a cliff fashioned by volcanic eruptions, layers of grey mud alternate with red ash.
17:50Transported to Beijing, these fossils allow 21st century researchers new insights into the feathered dragons.
18:09Like Cynosauropteryx, the first discovered in 1996.
18:16This specimen remains a source of fascination for one of China's most famous paleontologists, Xu Xing.
18:31I remember clearly, at that time when this discovery was announced, everyone got so excited, you know.
18:40You know, we are kind of shocked by the beauty of the fossil.
18:45If you look at this specimen closely, you see the feathers cover the whole body.
18:50You know, along the, over the head, over the back, cover the whole tail.
18:54A little bit here also, I mean, limb.
18:57Basically, feathers are quite simple.
19:01They are more like your hair.
19:03Before this discovery, some paleontologists believe some bird-like dinosaur should have feathers.
19:09But now we have real evidence, so that's totally different.
19:15The discovery of this feather-covered fossil was astounding.
19:18For the first time, they had found a dinosaur with avian characteristics.
19:24Proof that they were part of the same lineage.
19:27In conifer forests, growing in the shadow of volcanoes, lived Sinosauropteryx.
19:45It belonged to a group of carnivorous dinosaurs called theropods.
19:49These predators use sight and smell to hunt.
20:07One of its favourite victims is Zangioterium, one of the first mammals.
20:12Sinosauropteryx feathers look like the down covering modern-day chicks.
20:25They are so different from bird feathers,
20:27that for a long time, skeptics dismiss them as mere hairs.
20:42In 2010, Xu Xing focused on Sinosauropteryx's strange feathers,
20:51which looked like the down covering modern-day chicks.
20:55He began with careful observation of these feathers.
20:59By taking a sample and putting it under the microscope,
21:03scientists discovered fossilized pigments.
21:06These are melanosomes, cells that give feathers their colour.
21:15Xu Xing discovered circular shapes that produce a brown pigment
21:19and stick-like shapes that create a grey colour.
21:23He deduced that Sinosauropteryx was the colour of a squirrel
21:28with lighter stripes on its tail, but that's not all.
21:31We can use melanosomes to infer the colour, but more importantly for us,
21:37we want to use that information to support the hypothesis
21:42that those dark impressions in this particular specimen
21:46are bird feathers, not something else.
21:49Because if melanosomes are present, we can see quite confidently
21:53those are primitive feathers.
21:56Sinosauropteryx was undoubtedly covered in feathers,
21:59but this land animal was incapable of flight.
22:09So what use was this dino fuzz?
22:13Did it protect this warm-blooded animal from the cold?
22:17Possibly.
22:19But this theory is not easy to prove.
22:20To learn more about the climate in Liaoning during this period,
22:32Xu Xing teamed up with a laboratory in France.
22:35This theropod tooth, brought back from China by geologist Romain Amiu,
22:40holds the key to this meteorological mystery.
22:42A lot of researchers thought that fossils from that time couldn't preserve the weather conditions recorded during the animal's lifetime.
22:52It was a big challenge.
22:54We were going to test something unknown.
22:56Could we find out climate information or not?
22:59In a sense, we contest the water that the dinosaurs drank.
23:04A chemical reaction with the oxygen preserved in tooth enamel reveals the temperature of the atmosphere 120 million years ago.
23:13Romain made a major discovery that radically altered our preconceptions.
23:17At that time, there was a global climate that was similar or a little colder than current temperatures,
23:27which is very different from what we thought about the period of the dinosaurs that we had imagined as hot, tropical and the same throughout the world.
23:36Where Liaoning is, the climate was similar to what we have in the north of France, with very harsh winters.
23:43So dinosaurs would have seen snow in winter.
23:48So feathers were an insulating material.
23:52It meant they could keep warm and keep active throughout the year, like any other warm-blooded animal.
24:02Coincidentally, just as Romain published his research, the discovery of large-sized dinosaurs confirmed his work.
24:14New Tyrants, the aptly named Feathered Tyrants, were the super-predators of the time.
24:33Due to their large size, the remains of T-Rex's cousins are kept in a warehouse in a southern of Beijing.
24:39The U-tronus is a really amazing animal.
24:51You know, it is a really big animal, about one half tons in body mass.
24:58Yeah, euternus is really amazing animal, you know, it's a really big animal, about one
25:06half tons in body mass.
25:09It's body covered by feathers, really long feathers, so this is unexpected.
25:14You know, traditionally we thought, you know, when animals get bigger, it's for dinosaurs
25:19same, the lost feathers, reduced feathers, so at least the feathers are kind of sparse.
25:25And here we have a large-bodied dinosaur with dense and long feathers, so this is bizarre.
25:35The fact that such a large, warm-blooded animal was covered in feathers suggests that its body
25:40size was not sufficient to regulate its temperature, so the climate must have been very cold.
25:48The discovery of the largest feathered animal ever found confirms the hypothesis of a temperate
25:54climate with harsh winters.
26:02It proves that the theropod dinosaur of Leonin wandered into the winter snow 125 million years
26:10ago, and that the feathers of the little Sinusauropteryx and the huge euternus protected them from
26:18cold temperatures in this region of the northern hemisphere.
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27:14The insulating property of feathers remains a feature in modern birds.
27:26But it is not sufficient to explain how surface-dwelling dinosaurs evolved over millions of years to become birds.
27:36Among the theropods living in Liaoning, was there only one type of feather?
27:41And at what stage did dinosaurs begin to fly?
27:46Over time, Chinese paleontologists have unearthed many feathered creatures.
27:52On some fossils, like the Chaudypteryx discovered in 1998, Xu Xing found feathers that were not just simple filaments.
28:04With its large feet, it looks much like an ostrich.
28:08In this fossil, there are some really beautiful feather impression.
28:13Here you see two hands of this animal, and here is the middle finger.
28:19And you see feathers attached to the finger, this surface, and they go this way, so it's quite a big feathers.
28:25Chaudypteryx, literally meaning tail feather, comes from the same Chinese site as Sinosauropteryx in the same period, 125 million years ago.
28:43Scientists imagined that these chicks were imprinted on their mothers, just like modern birds, and followed them everywhere, more or less.
29:01Weighing almost 20 kilograms, the female Chaudypteryx can't fly, neither can her youngsters.
29:19So why do these animals have long feathers? Could they serve a purpose other than warmth?
29:41Feathers begin as a simple filament, which divides to form a pom-pom before barbs appear around the hollow shaft.
29:49But at this stage in their development, feathers are symmetrical, and air passes through them.
30:02So it is not flying anymore, it's fast-running anymore, living on the ground, so what's the function?
30:08Apparently those feathers are not used for flight.
30:12So the other possibility, most people believe, is a display.
30:19Just like many birds, the males and females were physically very different.
30:27Paleontologists believe that the male Chaudypteryx displayed his shimmering feathers in order to attract females.
30:34These courtship rituals, along with natural selection, stimulated an anatomical transformation.
30:53Chaudypteryx were among the first theropods to possess a shorter tail that supported their display feathers.
30:59In order to fly, they were still missing a fundamental element, flight feathers.
31:12Seen under a microscope, this feather comes from another dinosaur, discovered in 2000 by Shuxing himself.
31:27It is a vital clue to solving the mystery of the origin of flight.
31:31Here, feathers are highly asymmetrical, so asymmetrical feathers are normally considered to be associated with flight capability.
31:43These feathers are identical to those of modern birds.
31:46It may be proof that some dinosaurs could fly.
31:49Microraptor is definitely the most amazing species that discovered so far.
31:54It is a dinosaur, but you see it has asymmetric flight feathers, not only the feathers on the arms, but also on the feet.
32:04So we call it a four-winded condition.
32:06This is really, really bizarre.
32:08I know we have quite good evidence suggesting this four-winded condition is related to the origin of flight.
32:14For a long time, paleontologists believed that two-legged dinosaurs run along the ground in order to take off.
32:22But Microraptor's climbing claws opened up a new possibility.
32:29125 million years ago, in the part of China that Microraptor called home,
32:34the ground was fertilized by volcanic ash that encouraged the growth of lush vegetation.
32:39tall trees add a vertical dimension to the landscape,
32:45and the Microraptor, meaning small thief, takes advantage of them.
33:06Microraptor sported feathers on its arms and legs.
33:09With its four wings, it was probably the world's first basejumper.
33:33Four wings offer an advantage for gliding, but not for walking.
33:39A Microraptor on the ground is a Microraptor in danger.
33:47To be continued...
34:17According to Shuxing, tree-dwelling feathered dinosaurs like these would evolve to become
34:32birds.
34:37To better understand this transition, paleontologists teamed up with an ornithologist, Zuzongi.
34:47In front of him is an incredible collection of primitive birds found at Sietun.
34:53Like the feathered dinosaurs from the same site, they all date from the Cretaceous period,
34:58125 million years ago.
35:01I think there are over 500 specimens of Confuciusonis are collected in this museum alone.
35:10I think this is the largest collection of Confuciusonis in the whole world.
35:17This bird, like Confuciusonis, they are only shortly later than the earliest bird archaeopteryx,
35:30and they are transitioned in many flight apparatus, many features.
35:38Despite the claws on their wings, they are very similar to modern birds.
35:44They no longer have teeth, nor a long bony tail.
35:52They also have a furcula, the famous chicken wishbone, for attaching muscles to wings.
35:57And the males have two ceremonial ribbons ornamenting their behinds.
36:02They are very similar to the
36:32This sexual variation is similar to that of the feathered dinosaur, Chaudypteris.
36:46Like him, the male has long feathers that he uses to lure the ladies.
36:56Competition is tough and courting displays are often interrupted.
37:23Also you can see the bird start climbing the trunk with very big claws in the wing.
37:32Now you see the bird can perch on the branches of the trees because the hallux of the foot
37:38is already reversed, much like a modern bird.
37:44Confucius Onus's narrow feathers were not well adapted to gliding.
37:56It would have allowed it to fly by flapping its wings, albeit clumsily.
38:01But natural selection is at work, retaining only the most adept genes.
38:13Yet the presence of many birds found at the same location as feathered dinosaurs
38:18does not necessarily prove that they were related.
38:24If birds had already diversified 125 million years ago,
38:30Eutyranus and other theropods may have been merely an evolutionary dead end.
38:37So when did the first birds appear?
38:40Did they share a common ancestor with feathered dinosaurs?
38:45And how did their ancestors begin flying?
38:51To answer these questions, Chinese paleontologists have one last card up their sleeves.
38:57West of Lia Ning, a new fossil bed was revealed during the construction of a motorway.
39:12In 2009, a finely preserved Ancyonis, dating from the Jurassic period, was found near here.
39:22It was to become a crucial piece in Shuxing's puzzle.
39:26This site is very important for at least for one reason.
39:30We know that Archaeopteryx, the earliest known bird, is from about 145 million years ago.
39:35But most other feathered dinosaurs are, you know, from early credit years or even later.
39:42So this dinosaur was living in like 160 million years ago, earlier than Archaeopteryx.
39:48So that means there are some feathered dinosaur predates Archaeopteryx, the earliest bird.
39:54So that's a correct time sequence.
39:59This new fossil puts an end to the debate.
40:02Feathered dinosaurs are undoubtedly older than the first birds.
40:09Today, Shuxing discovers a fish, confirmation that Ancyonis lived in a rich ecosystem.
40:15This little four-winged theropod must have been a victim to giant predators.
40:29In the Jurassic period, pterosaurs, like these Darwinopterus, ruled the skies.
40:34With talon-like claws and a wingspan over a meter wide, they were the equivalent of modern-day birds of prey.
40:42Their ability to fly and perform aerial acrobatics was beyond that of the feathered dinosaurs.
40:51Faced with this constant danger, Ancyonis sought shelter in the forest.
40:58But this little dinosaur was also threatened from the ground.
41:01Its only shelter lies in the restricted area between the ground and the sky, the trees.
41:08It glides down to feed in the undergrowth.
41:17Its surface area is smaller than Microraptor, so it falls more quickly.
41:22With its long back legs, Ancyonis is built like a sprinter.
41:30But its lengthy feathers are a hindrance on the ground.
41:34Its long legs are an advantage for foraging or rushing to the nearest shelter.
41:39If such a thing exists.
41:40If such a thing exists.
41:42If such a thing exists.
41:46I hope you all have the elements.
41:47Aman!
41:48Thanks again!
42:04Isn't it fantastic, Jon?
42:09Myself!
42:14Though clumsy, Ancyonis showed that dinosaurs attempted to fly from trees using four wings.
42:29On this rare fossil, the rear leg feathers are visible to the naked eye.
42:42To refine his theory, Xu Xing continues his research using a medical scanner.
42:48X-rays of Ancyonis' skeleton will be digitized in 3D in order to study its biomechanics.
43:01But honestly, there are some debates how exactly those animals use their leg wings.
43:06Some people believe the leg wings are not really related to flight.
43:10Ancyonis is a display structure.
43:12If you look at other dinosaurs, their leg normally is underneath the body.
43:17They have a cool erect posture.
43:20One possibility may be Ancyonis can project its leg slightly laterally.
43:25To compensate for the lack of a wishbone, Ancyonis used its rear leg feathers to improve its gliding ability.
43:33The discovery of Ancyonis proves that dinosaur flight was a result of trial and error in the evolution of anatomy and feathers.
43:50Surprisingly, new information about the origin of feathers was soon to appear from over the border.
43:56In Siberia, in the summer of 2013, the first Russian feathered fossils made their appearance.
44:041500 kilometers north of Beijing, in the Transbical Steppe, a team of Russians and Belgians worked together at the excavation site.
44:21When local geologists found the first bones, they invited paleontologist Pascal Godefroy from the Royal Institute of Belgium to take part in this revolutionary discovery.
44:39We are at the Kulinda deposit in southeast Siberia.
44:49The hills you can see behind me date from the Jurassic period between 145 and 160 million years ago.
44:56And Russian geologists who were prospecting in the area in 2010 found the first dinosaur bones,
45:02which have been extremely important for reconstructing the evolution of plumage and feathers in dinosaurs.
45:08His curiosity aroused, Pascal assembled a team to search the site for themselves.
45:15It's a lengthy process, requiring a deep layer of soil to be removed to get to the fossils.
45:22But after several days, the team's work starts to show results.
45:28Look at that.
45:38That's quite a big deal.
45:41Just there, at the edge.
45:43Oh, wow.
45:44That's one.
45:46So here, at the edge of the plate, you can see very fine little filaments.
45:55And these are feathers, dinosaur feathers.
45:58You can see that the filaments converge towards the base.
46:01So these are composite feathers.
46:03It's a primitive kind of down that we find on some primitive dinosaurs.
46:09Compared to the impressive Chinese discoveries, these fossils may seem a little underwhelming.
46:18But the paleontologists are thrilled to discover a completely new animal species.
46:24During the Jurassic period, the Chinese peninsula was covered in a vast forest of conifers.
46:37While Siberia was much more hostile.
46:40The arid climate had huge seasonal variations in temperature and intense volcanic activity.
46:47One of the keys to conserving precious fossils.
46:51Only fragments of skeletons are found at Kolinda.
47:05To begin with, the Russians thought that the feathers came from fossilized birds.
47:12The scales from crocodiles.
47:18And the bones from a small predatory dinosaur.
47:26But Pascal was not convinced by this hypothesis.
47:31In 2014, he re-analyzed all the fossils.
47:35And suggested an entirely different explanation.
47:39It's a bit like going into a cemetery and gathering up loose bones.
47:43You'll have small tibias, large tibias, little femurs and big femurs.
47:49But they all have the same morphology.
47:51So we can tell they all come from the same type of dinosaur that we called Kolinda Drameus.
47:59Because of the large number of disconnected bones that we found at Kolinda,
48:03we now know that Kolinda Drameus was a small herbivore dinosaur that was fast, slender and agile.
48:10This is the first ever feathered herbivore dinosaur to be discovered.
48:17A separate branch of the dinosaur family tree from the carnivorous theropods.
48:31Kolinda Drameus lived in herds.
48:36Just like wildebeest migrations in Africa,
48:39large predators, such as Cynraptor,
48:42must have closely followed the movements of these dinosaurs.
48:48was influenced by all the local forces of humans.
48:53At the top of the Chandi untenized the army,
48:55must have been incorporated into the genommen of the
49:01dungeon展開 demolished into the forest.
49:11We should be chosen to project animals through burningqing,
49:16this is a real revolution what it means is that all dinosaurs could potentially have had feathers
49:24feathers would have appeared on an ancestor that was common to both groups it could be as old as
49:33dinosaurs themselves first seen in the triassic period 220 million years ago the misfortunes of
49:52this group of herbivores have led paleontologists to the origins of feathers
49:58thanks to colinda dromius we now know that the first feathered dinosaur the common ancestor of
50:09the carnivores and the herbivores remains to be found in fossil beds going back to before the
50:16jurassic period but who knows what other secrets could be found in siberia and what clues could
50:39be hidden in other parts of the world to document the early history of the bird dynasty
51:09so
51:16so
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