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Documentary, Monsters of Ancient Australia - 4 Billion Years Ago
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00:00Over four billion years in the making.
00:06An island adrift in southern seas.
00:11It's Australia.
00:12The giant down under.
00:16A young nation.
00:19With all the gifts of the modern age.
00:23That moved beyond the cities.
00:26And an ancient land awaits.
00:30One nearly as old as the earth itself.
00:40Australia is a puzzle.
00:42Put together in prehistoric times.
00:47And the clues that unlock the mystery.
00:50Can be found scattered across Australia's sunburned face.
00:56Oh!
01:00I'm Richard Smith.
01:02And this is an amazing country.
01:07I'll show you that every rock has a history.
01:10Every creature, a tale of survival against the odds.
01:17Join me on an epic journey across a mighty continent.
01:21And far back in time.
01:24Of all continents on earth, none preserve the great saga of our planet and the evolution
01:32of life, quite like this one.
01:35Nowhere else can you so simply jump in a car and travel back to the dawn of time.
01:41In this episode, out of the chaos of disaster, rises a new world order, ruled by reptilian tooth and claw.
01:53It's the age of dinosaurs down under.
01:58Join me as I retrace the footsteps of predators and prey.
02:03And dive into a long lost sea.
02:05And dive into a long lost sea.
02:07From Australia's ancient stones, comes the story of our world.
02:14Australia's first four billion years.
02:20Monsters.
02:22Right now, on NOVA.
02:25It's a long journey back to our modern world.
02:55From distant, ancient Australia.
02:57From the birth of the earth to the present day, the road of time stretches a mind-boggling 4.6 billion years.
03:15It helps to imagine, just for a moment, that this car can travel through time.
03:23I set the controls for a million years per minute.
03:29That's 60 million years of history for every hour we travel down the road.
03:35You want to see the real, old Australia.
03:37It's quite a ride.
03:41Your destination is the Mesozoic.
03:47Traveling at a million years per minute, the entire story of Australia and the planet is condensed into a little over three days of solid driving.
03:57And for most of those first three days, we have roared through the infancy and childhood of the Australian continent.
04:09Now, with 70 hours of my journey behind me, and only another four to go, we've arrived at the start of Australia's wild adolescence.
04:21It's the Mesozoic.
04:25It's the most familiar of all geological eras.
04:39And for good reason.
04:43It's in the Mesozoic, home of the Triassic, Jurassic and Cretaceous periods, the dinosaurs ruled the earth.
04:55But despite such world domination, evidence for their conquest of Australia has been a little thin on the ground.
05:07Until now.
05:13Time for the age of dinosaurs.
05:18Down under.
05:29The Triassic, the first of the three great periods that made up the Mesozoic, got off to a pretty shaky start.
05:36The Permian crisis, the world's most catastrophic extinction event, was over.
05:44But gone with it was perhaps 95% of the biological diversity of the planet.
05:55Around the world, life had been all but wiped out in the sea.
06:01And devastated on land.
06:06Yet somehow, out of the carnage and confusion of that devastated world, rose a new one.
06:19And with it, the dramatic sandstone landscape of Sydney.
06:27I think Richard, this would have to be one of the best places to see the Sydney sandstone.
06:31There's the Pacific Ocean.
06:35There's North Head over there.
06:37There's the entrance to Sydney Harbour, just behind us there.
06:40Over here's the gap.
06:42And a lot of rock underneath us.
06:44There's about 250 metres of solid sandstone.
06:47Biologist Tim Flannery knows the landscape of my hometown world.
06:53Sydney, it seems, was built on the aftermath of disaster.
06:59We would have been standing when this sandstone was laid down in a post-catastrophic world.
07:08We've had the great disaster of the Permian extinction, with life almost extinguished.
07:1295% of all species gone.
07:14Even plants struggled to recover.
07:20The colourful forests and rich coal swamps of the Sydney Basin had gone.
07:26And over the next 20 million years, the lush world of the Permian was buried deeper and deeper in sand.
07:35There's been some recent studies suggesting that this sand here, particularly, may have come from as far away as East Antarctica.
07:43And that is a massive distance.
07:45Storms raged on those distant mountains.
07:51And rivers thundered from their denuded slopes, carrying unimaginable quantities of sand northwards across vast, spreading floodplains.
08:01This rock talks to me of a time when life was slowly recovering, but there's not even enough life and vegetation to hold the banks of the river together.
08:13It's just this great braided system running across the landscape.
08:18I can just imagine standing there, seeing these ripples six metres high, imagining this world where the physical processes of the planet are just laid so bare.
08:26These sand grains saw that. They, the sun that was shining down on the planet then, struck those sand grains that we're standing on now.
08:37And it's that great physical reminder, that's why I love geology, you know, that you know that that rock was there at the time, 230 million years ago.
08:44Shifting sand has turned to solid stone.
08:55And the debris from the end of the Permian world is now the foundation for a new one.
09:00Now, after waiting quietly in the dark for some 230 million years, the lost sands of Antarctica have a new job as the bedrock and building blocks of a great global city.
09:19Sydney is defined by its Triassic geology.
09:26From the warm glow of its stone buildings to the shape of its harbour, the sandstone dictates everything from the flow of traffic to the form of its native flora.
09:40The sandstone cliffs stand hard and proud against the Pacific Ocean and weather into the soft golden sands of the surf line.
09:53The sand also buries the Permian peak lands, allowing them to become the coal that powers the city.
10:03And rising to the west, this same sandstone forms the rocky ramparts of the Blue Mountains and the Great Dividing Range.
10:18All of this, a legacy from the dark days when the Earth nearly died.
10:27It was the sudden lurch into an intense greenhouse climate that seems to have triggered the initial disaster at the end of the Permian.
10:46A series of wild climate swings then plagued the early Triassic before the planet finally stabilised.
10:53And even when it did, temperatures still simmered.
11:04Conditions would have remained pretty hot and dry no matter where you went on the planet.
11:09Australia was still part of the supercontinent Gondwana, but Gondwana was now part of a super supercontinent called Pangaea,
11:16where all lands were one, and given a decent four-wheel drive.
11:21You really could have gone just about anywhere.
11:25Australia had joined the wild bunch, though it was very much at the bottom of the continental pack.
11:31Australia lay near where Antarctica does today.
11:40But this was a South Pole in an ice-free greenhouse world.
11:45There were ferns and ginkgo trees, freshwater fish, and giant carnivorous amphibians.
11:53But the Triassic Earth belonged to reptiles.
12:00Some were taken to the air, others to the sea.
12:06Walking the land were lizard-like reptiles, mammal-like reptiles,
12:12and the first dinosaurian reptiles as well.
12:15Though we know these early dinosaurs roamed across southern Gondwana,
12:24they've left almost no trace here in Triassic, Australia.
12:32But the evidence for Australian dinosaurs is out there, if you know where to look.
12:38The old gold mining town of Mount Morgan in central Queensland is one such place.
12:56When the old miners excavated clay from a nearby hill,
13:00what they dug away was the mud that once filled a Jurassic lake.
13:05So this was all lake, a lake deposit here?
13:08It was, yes.
13:09So we're in underneath where the dinosaurs walked on the edge of that freshwater shallow lake.
13:16Left behind in the rocky ceiling are the three-toed imprints of dinosaurs
13:22that walked on the lake's muddy fringe.
13:27The ghosts of dinosaurs past still haunt these caverns.
13:31There's a few up here.
13:32Oh, yes, yes, yes, yes, yes.
13:33These footprints, and those from other mines,
13:37help flesh out a Jurassic Australia rich in forests and waterways.
13:47I'm standing in what was the muddy edge of a lake.
13:50And up there, on the lake's surface, a theropod once walked above me.
13:54About 190 million years ago, an imprint as clear as day.
14:09But Australia is big and old and red and flat.
14:13This is a geological landscape that has kept its Mesozoic secrets well hidden.
14:25The botanical landscapes Australia's dinosaurs walked in, though,
14:29are much easier to experience.
14:33You can still walk in them today.
14:34The Mesozoic was a great time for plants.
14:43The earth was an ice-free greenhouse world, warm and wet.
14:49Thick forests spread around the globe,
14:54and the southern lands of Gondwana were no exception.
14:58Cycads, ferns and ginkgos were common,
15:04and had now been joined by the tree ferns
15:08that still abound in the rainforests and gullies of eastern Australia.
15:11But the standout trees of Mesozoic forests worldwide were the giant conifers.
15:22Luckily, some of those giant conifers are still with us.
15:27This towering sentinel is a Queensland Bunya pine.
15:32And it's remarkable not only for its great size,
15:35but because it's so little changed.
15:41The Bunya, Hoop and Cowrie pines of eastern Australia
15:46are well-known living fossils from the days of the dinosaurs.
15:52But in 1994, the ultimate pinosaur was discovered.
15:58The Wollemi pine.
16:01A green giant, 130 feet tall,
16:05and hiding only 100 miles from Sydney.
16:07Here, in a couple of secret canyons,
16:11are less than a hundredth
16:13of perhaps the oldest surviving tree species in the world.
16:17The spitting image of fossils from as far away as Antarctica.
16:22Today, the great conifer forests of Australia are gone.
16:38But the few surviving pockets allow you to dream of the days
16:42when you could have driven from coast to coast with not a eucalyptus leaf in sight.
16:54The Mesozoic Earth was restless.
16:57Like a teenager with a growth spurt, it was on the move again.
17:00The supercontinent Pangaea was breaking up,
17:04leaving Australia still attached to a remodelled Gondwana in the southern hemisphere.
17:13And around the end of the Jurassic,
17:18a little extra remodelling was applied from space.
17:24A falling rock, in the shape of an asteroid or comet,
17:30slammed into central Australia.
17:32It was a bullseye that you can still see.
17:44Almost bang in the middle of the continent.
17:50As impressive as it is,
17:52Gossa's Bluff, or Noralla to give it its indigenous name,
17:56is a shadow of its former self.
17:58Most of the original 13-mile-wide crater has been worn away.
18:07What's left is merely the bowl punched deep into the earth,
18:13below ground zero.
18:17Still, the Ring of Low Hills gives a pretty good hint
18:21at the scale of utter devastation
18:23that must have been visited upon the land
18:25for at least 60 miles in every direction.
18:37Sometimes you get a chance to truly grasp
18:40the scale of past geological events.
18:42And when you do,
18:44it's truly humbling.
18:45It wasn't the Gossa's Bluff impact that did in the dinosaurs.
18:52But it was a portent of dangers to come.
18:56When dawn broke on the Cretaceous,
19:13dinosaurs still had their claws on the continent.
19:16From one side of it to the other.
19:25It's been a long wait.
19:27But finally, the 21st century is throwing new light
19:31on the Australian dinosaur story.
19:33For years, the ancient secrets of the Kimberley coastline near Broome
19:46have been guarded by extreme tides
19:49and extensive crocodile-inhabited mudflats.
19:51It makes for an easy place to imagine
20:01what might have been walking the land
20:04in the primeval past.
20:10But imagination alone is not required here.
20:13The giant beasts of the early Cretaceous
20:16have made their presence clear to us.
20:24The first clear chapter in Australia's rather secret history of dinosaurs
20:28starts here, on the beaches near Broome in the Kimberley.
20:33Back then, this was a vast coastal forest
20:36running down to flood plains and estuaries near the sea.
20:39Not radically different from the tropical mudflats of today,
20:42except for the 15 or so species of very large dinosaurs
20:46that have left their marks in the rocks here.
20:53A rich reptilian community once stomped this landscape.
20:57Dinosaur footprints stretch over 60 miles of coast.
21:01They must have been everywhere.
21:12Even a suspected stegosaur left its mark here.
21:17One of only a handful of such five-toed prints in the world.
21:21But the largest and most abundant footfalls
21:26belong to the towering vegetarian sauropods.
21:30And this is the trackway of one large sauropod
21:34that came wandering past Broome
21:35around 130, 235 million years ago.
21:39Big footprints. One there, another one there, a big footprint here.
21:43And interspersed amongst them, some smaller footprints.
21:46Thought to have been made by a calf, wandering with its mother.
21:49There's little evidence though, for parental care in sauropods.
21:58And once you reach this sort of size, little need for it.
22:02Finding enough to eat was probably a bigger concern than avoiding predators.
22:07But for most Australian dinosaurs, day-to-day life was a hazardous experience.
22:17As a small herd discovered 95 million years ago, near Winton in Queensland.
22:22That moment is frozen in time here, at Black Quarry.
22:29The sight, it's been thought, of the world's only recorded dinosaur stampede.
22:36Picture the scene here, one ordinary day in the Cretaceous.
22:43This was a broad, muddy spit, running down into a lake just over there.
22:54Now sometime during the day, a mixed herd of small dinosaurs
22:59wandered across the mud to take a drink at the water's edge.
23:02Here you can see the very clear footprints of a small chicken-sized meat-eater.
23:07And here the emu-sized tracks of an ornithopod dinosaur.
23:17But behind me, probably more or less where the wall is,
23:21was the start of a forest of tree ferns and ginkgo trees.
23:24These rich forests, dominated by conifers, provided shelter and food.
23:39And cover for a meat-eater.
23:45Even for a wary dinosaur, the Cretaceous was no time for complacency.
23:51Now if you'd popped your head up and looked back this way,
23:55you would have seen one very large, very hungry theropod,
24:00head down and heading your way.
24:02In the pandemonium that followed,
24:12150 terrified dinosaurs scattered in all directions,
24:16sliding on the mud and crashing into each other
24:19as they raced to reach the relative safety of the forest beyond.
24:22Footprints can only ever tell part of the story.
24:38Bringing Australia's true blue dinosaurs to life
24:42needs bones.
24:43And finally, those bones have also started turning up.
24:58Here's coffee.
25:02Slowly coming together.
25:04Very, very slowly.
25:06They've come to occupy a very special place
25:08in the lives of sheep farmers David and Judy Elliott.
25:11Only about 10,000 pieces to go. You're going well.
25:14Yeah, I'm doing really well.
25:16And yes, that is a dinosaur on their kitchen table.
25:21It's a pile of rock that's got tiny bones in it.
25:25And we've dubbed it chook, or chooky,
25:29because that is about the size of the animals that the bones relate to.
25:34So, it's chooky.
25:36Hunting dinosaurs was never part of the Elliott's business plan.
25:40But they're fast becoming experts.
25:43This dinosaur site that we're going to is probably the most exciting
25:48and is definitely the most significant of what I've found so far.
25:51And it's a place that's produced a tremendous amount of material in quite a short time.
25:54The Elliott's began their dinosaur odyssey by accident.
26:05Pretty much by tripping over the bones of some dead ones on their property.
26:10So Dave, this is a big hole in the ground?
26:16Yeah, here we are.
26:18This is where it all started.
26:22If you can imagine, 95 to 100 million years ago,
26:26we were sitting in a lush rainforest area.
26:28Look back in the north, and where we have nice, you know, flat, open grasslands,
26:34that would have been an inland sea.
26:36And what we had is these big rivers coming in and bringing silt
26:40and just depositing silt,
26:42so slowly that sea was being pushed back to the north.
26:45So this country here was cool, it was lush, it was green.
26:48The rivers were full of lungfish and turtles, big crocodiles and freshwater fish.
26:52From what they've seen so far, David's convinced the dinosaurs being unearthed
27:00have a unique Australian pedigree.
27:03The dinosaurs out here are totally different.
27:06And that's so true for just about everything Australian, isn't it?
27:10Even us. We're a little bit different, aren't we?
27:15Before the dinosaurs showed themselves in western Queensland,
27:18Winton was most famous for a song.
27:25A visit to this billabong, an outback waterhole,
27:29inspired bush poet Banjo Paterson
27:32to pen the country's most famous national tune.
27:41That legacy lives on.
27:42Each animal being revealed to us, bone by ancient bone,
27:47is given a local nickname.
27:53If there's a dinosaur, say, comes from the Winton area,
27:55then it needs to have that context.
27:57And one of the strongest contexts, of course, with Winton
28:00is Banjo Paterson, waltzing Matilda, and that link.
28:04Not exactly waltzing, but here's one big-boned girl, the sauropod Matilda.
28:15Matilda stretched 60 feet tip to tail,
28:21and stood 13 feet high at the hip.
28:24And then there's Banjo himself, the fearsome southern hunter.
28:38You look at these things, and they're just guinea bones, really.
28:41They don't look all that significant.
28:43But you start fleshing these bones out,
28:45and putting sinews on them, putting muscles on them.
28:48And then you put that leg on that animal, as it would have stood,
28:52and you can see that what we're dealing with isn't any spring chicken.
28:56It is one hell of a big and very dangerous dinosaur.
28:59And it's not the sort of thing that you'd particularly like to have,
29:01chasing you up the garden pass or down the hallway.
29:03What you've got is an animal that didn't rely on its teeth to kill.
29:15Massive claws, massive big beefed up arms.
29:18So imagine just getting its claws in, driving them in,
29:20and just tearing it apart.
29:21It would have had that strength.
29:29In an extraordinary twist of irony,
29:31it now turns out that the spot where the bones of both Banjo and Matilda were found
29:36was indeed a billabong.
29:47It's not quite Jurassic Park,
29:50but after years languishing as a dinosaur backwater,
29:54Outback Australia is opening up as the hot new Cretaceous playground
29:58for paleontologists.
30:05It's always been a big country out here.
30:08And after an unusually wet year,
30:11this red landscape is so green,
30:14it even looks like it could carry some pretty large livestock.
30:16A 500-mile drive south of Winton brings you to the site of some of the biggest dinosaur discoveries yet.
30:31Near the small town of Eremango.
30:34Population, 171.
30:37A warm summer's day here is 117 degrees.
30:44As far as towns go, Eremango is no Titan.
30:48But that's not so true of the bones found on nearby Plevnadown Station.
30:53In a thundering echo of the Winton story,
31:00ranchers Robin and Stuart Mackenzie have been unearthing bones belonging to some of the largest dinosaurs
31:07to have ever shaken the planet.
31:09This enormous drumstick is over six feet long.
31:17A giant leg bone from an as yet undescribed species of Titanosaur.
31:24A big bloke called Cooper.
31:27Cooper's approximately 95 million years old.
31:30And so what we've got here is the largest bone of the largest animal
31:36that ever walked around on Australian soils
31:40and is actually up there in the top ten in the world.
31:47At over a hundred tonnes,
31:50and with a hip height as high as the hotel roof,
31:53this giant would have barely fit in Eremango's Main Street.
31:57Australia is really in a natural history revolution.
32:03There's dinosaurs being found all over Queensland, central Queensland,
32:08from Winton down to Eremango, and even in southern Australia.
32:11So in the last decade we've found hundreds and hundreds of dinosaur bones,
32:15from the smallest dinosaurs to the largest.
32:18There's no stop to it now.
32:19For a tiny town, Eremango can make some big claims to fame.
32:28Being the furthest town from the sea in Australia is another one.
32:33But it wasn't always so.
32:36Ask a geologist and they'll tell you the town has lent its name
32:40to the largest inland sea in Australian history.
32:43By the middle of the Cretaceous,
32:49ocean levels were on the rise again,
32:51climbing 600 feet above today's levels.
32:55With the centre of the continent already subsiding,
32:59the sea flooded in to central Australia.
33:04Today, Eremango's only reliable source of water comes from underground,
33:09the Great Artesian Basin.
33:101909 it was first sunk.
33:14It's one of the largest artesian basins on the planet.
33:17It's 160 psi of pressure at 100 degrees Celsius.
33:24Got to be very careful working around it.
33:35The heat comes from the warmth of the earth over half a mile below us.
33:40It's smelly because it's been trapped down there for a million years.
33:45Of course, this isn't stinky prehistoric seawater coming out.
33:51Rather, it's fresh groundwater that's taken an age to seep deep into the porous stone
33:57that was once the sand at the bottom of the Eremango Sea.
34:00Without the Eremango Sea, there wouldn't be a Great Artesian Basin.
34:05It's the fine muds of the old Eremango Sea floor that seal the top of the Artesian Basin.
34:13Mark out the boreholes that tap into it, and you can pretty much draw a map of where the ocean used to be.
34:23About 120 million years ago, the Eremango Sea spread out over a quarter of the continent.
34:34I'm heading to Coober Pedy on its southern shoreline.
34:43Scattered on the outskirts of town are strange clues to its past.
34:48Petrified driftwood.
34:52The salty glint of gypsum.
34:57Even rocks dropped from winter ice that once rafted overhead.
35:01Today's mysteriously beautiful landscape was once a seascape.
35:20When the first European explorers made it out here to central Australia,
35:24some of them expected to find an inland sea.
35:27Now, we all know they failed, but not because it was a silly idea.
35:33They just got here 120 million years too late.
35:39Arrived when the tide was still in.
35:42And you would have found the Eremango Sea full of monsters.
35:48Toothy marine reptile monsters like plesiosaurs and ichthyosaurs.
35:54Air-breathing animals that had returned to the sea.
35:59Both these types of reptiles are known to have hunted in Eremango waters.
36:04And they died here too.
36:08Sometimes a corpse sank to the sea floor and fell all the way to the future.
36:13These days, Coober Pedy bakes in the heat.
36:24It might look like a ramshackle collection of mine shafts, underground houses and tourist traps.
36:31But this is Opal Central.
36:34The diggings here produce over 70% of the world's supply of this rainbow-hued treasure.
36:44So it's no surprise Opal is Australia's national gemstone.
36:49What you do is pull it and you're going to go down slowly.
36:56Feel like an ant.
36:58Yeah, don't go looking up too much.
37:00Brothers Steve and Drago Marjanovic make their living prizing these precious stones from the ancient seabed on the outskirts of town.
37:08This is their daily commute.
37:13A tight fit dangling on a wire, 70 feet down a giant wormhole.
37:22Wow!
37:24Hi Drago.
37:26Come on mate.
37:28Drago was offered to lead marine reptile expert Maria Zammert and I
37:31Welcome.
37:32Deep into the prehistoric Eremangas seafloor.
37:38The brothers have dug an extraordinary catacomb of shafts and tunnels into a Cretaceous marine graveyard.
37:45So Drago, is it hard to tunnel through this?
37:48Oh yeah, yeah.
37:49Opal formed here, it's thought, when silica-laden water leached through the rock,
37:54pooled where it met resistance,
37:57and then slowly evaporated.
38:02Occasionally, when this mineral rich water encountered a fossil,
38:07a biological treasure became a mineralogical one as well.
38:11Wow, that is just beautiful.
38:14That green one is stunning.
38:16And it's clearly a shell.
38:18You're absolutely right, you can really see that they're shells.
38:21I mean that tells us a little bit about the seabed that was here at the time.
38:24However, for me of course the favourite are the vertebrate fossils,
38:27so the parts of those marine reptiles that you do occasionally get opalised.
38:37These are some of the opalised body parts recovered so far.
38:42Back bones.
38:44Rib bones.
38:47Tail bones and flipper bones.
38:49Near complete skeletons from long-dead reptilian sea monsters.
38:56I've heard of some descriptions of them being like a snake threaded through the body of a turtle.
39:03And that's really what they look like.
39:06They've got these gigantic flippers attached to this body,
39:09and then you've got this long neck stretching out in front.
39:15Enough plesiosaur remains have now been found to determine that many found in the area were juveniles.
39:26You do see some that are only about this big.
39:28So, you know, they're obviously juveniles.
39:31How young?
39:32We don't know if they're just newborn babies or if they're slightly older than that.
39:37But it is suggested that, because we see so many specimens that show these signs of being quite young,
39:43that it was a nursery.
39:47Plesiosaurs could carve and fatten up in the nutrient-rich summer waters,
39:52heading north again before the winter returned.
39:54It might have been a safer place than most to raise a youngster in a dangerous ocean.
40:15Sail out into the Eremanga Sea,
40:18and you would have encountered a host of strange Cretaceous sea creatures.
40:21And it's highly unlikely that they were all as friendly as dolphins.
40:30What I think is amazing is if this was 100 million years ago,
40:34we'd be travelling over very similar seas to this,
40:37but when we got there, we wouldn't be looking for these strange animals.
40:40They'd be looking at us.
40:42Marine biologist Mark Norman and I are off to meet one of the strangest survivors
40:47from these Cretaceous seas.
40:52It's the Nautilus.
40:54No, it should have been straight through here.
40:57It's not easy to find.
40:59These days, this ancient mollusk hides away far below the reach of daylight and divers,
41:06on the deepest reef walls in the Coral Sea.
41:09A trap has been sitting at depth overnight, set with some unusual bait.
41:23There's a taste for chicken.
41:27Went against them.
41:29The phrase living fossil gets used a lot for these long-lived ancient groups of animals.
41:36These went through seven mass extinctions.
41:39The dinosaurs didn't make it through one.
41:42The Nautilus.
41:43And their relatives over 500 million years are the great survivors.
41:49Modern day relatives of the Nautilus are squids, cuttlefish and octopus.
41:56All cephalopods.
41:57A clan with a long and proud history.
42:01Meet a face from the distant past.
42:07Eyes for sea and hidden within a nest of 90 tentacles.
42:12A mouth for eating.
42:13Primitive it may be, but this whole prehistoric package is jet propelled.
42:27The distant ancestors of the modern Nautilus were the Nautiloids.
42:34We know them from their fossil shells.
42:37Which in the early days were mostly straight.
42:43For hundreds of millions of years, these sorts of animals dominated our oceans.
42:48And got to massive sizes.
42:50Some of the straight ones got to 10 metres long.
42:53So they were like giant telephone poles bobbing along, hoovering up trilobites.
43:06By the Cretaceous, it was the Nautiloids' coiled cousins, the Ammonites,
43:11who ruled the molluscan world.
43:16Some grew larger than tractor tires.
43:19And they must have had an appetite to match.
43:30Rich pickings were to be had throughout the Aramango.
43:32For mollusc and reptile alike.
43:33Out here, even a long-necked plesiosaur needed eyes in the back of its head.
43:49For the Aramango was the hunting ground of perhaps the greatest sea monster of all time.
43:55The Pliosaur Chronosaurus.
43:58So here we have just the skull of Chronosaurus Queenslandicus, the largest marine predator of all time.
44:13We started its snout.
44:14We go past these amazing teeth, these crushing, bone-crushing teeth.
44:19Back to the back of the skull.
44:20Here is where the actual eyes would have been.
44:23And right where I'm standing, two metres away, is the back of the skull.
44:31This toothy monster was a meat-eating machine.
44:34And we can even see what its last meal was.
44:40Right here is a rib cage of Chronosaurus.
44:43And inside its stomach, we can see the vertebrae of its meal.
44:48This is a long-necked plesiosaur.
44:49And it even preserves the stomach stains from this animal.
44:53On top of that, we have turtle.
44:56So this animal was eating long-necked plesiosaurs and turtles.
44:58These were the dying days of Gondwana.
45:10Africa had long ago slipped off to the west.
45:14Now India was gone too.
45:17Even at the bottom of the world, the strain between Australia and Antarctica was beginning to show.
45:29Marking the boundary between the separating continents was a rift valley, rich in forests, lakes and rivers.
45:41But this entire landscape lay within the Antarctic Circle.
45:46So close to the South Pole, that in the summer, the sun never set.
45:52And mid-winter would be dark for months on end.
45:56And that made it interesting, when dinosaurs started turning up here as well.
46:06For over three decades, paleontologist Tom Rich has been on the hunt for bones of animals that lived in these primeval polar forests.
46:15There aren't many places anywhere in the world where you get polar dinosaurs.
46:21So that makes this site and this area physically important.
46:29Australia was one of the most isolated blocks of land at that time in the world.
46:35So things we might find out about this are things we won't find anywhere else.
46:38It's almost as if there's an independent experiment evolution going on here.
46:50Some of these experiments were small ornithopod species like these.
46:55Outwardly conventional, these were rare dinosaurs, thought to be permanent polar residents.
47:05Their bones lacked signs of a hibernating lifestyle, suggesting they remained active right through the long chilly gloom of the sunless winter.
47:15But the dinosaurs weren't the only polar pioneers living in these dark forests.
47:25Some had fur.
47:27While reptiles may have ruled the world from the poles to the tropics, it's easy to forget.
47:46They didn't have the planet all to themselves.
47:48There was another type of animal hiding in these prehistoric forests.
47:58They're still here, and there's one just over there.
48:05The ancestors of the platypus have been poking their mammalian noses into the billabongs and waterways of Australia for at least 120 million years.
48:15Proof is kept locked in this safe at the Australian Museum in Sydney.
48:27It's another opalised national treasure.
48:31A tiny lower jaw from an ancestral platypus.
48:35A wonderful iridescent gem recovered from a lightning ridge opal mine.
48:40Warm-blooded, furry, and for the most part small, the mammals we know existed at the time could hide and hunt in the shadows of the giants.
48:56They were born survivors.
48:59It went with the territory.
49:01Like all empires, the reign of the dinosaurs was coming to an end.
49:10And they might have seen it coming if they looked to the sky.
49:15When an asteroid slammed into Mexico's Yucatán at the end of the Cretaceous, the repercussions were felt around the world.
49:33Though Gondwana and Australia escaped a direct hit, within an hour of impact, bits of pulverised Mexican sea floor flung into space began raining back down all over the planet.
49:53In places, it would have turned the sky as hot as a giant rotisserie.
50:06No good record of this bad day on planet Earth has been found yet in the rocks of Australia.
50:11But step across to the South Island of New Zealand and you'll find hard evidence for the blanket of cosmic dust that's settled over the planet.
50:27This, believe it or not, is the moment that the world changed forever.
50:31Now, it might not look like much, but this thin grey band of rock found around the world offers a remarkable window into one of the most dramatic events in the planet's history.
50:43Below this boundary lie dinosaur bones.
50:46And rising in the rocks above is a world clearly recovering from a catastrophe.
50:51The days were numbered for any Australian dinosaurs that clung on after the initial impact.
51:06A tremendous darkness, it's thought, in the form of salt, dust and smoke, settled over much of the world in the immediate aftermath.
51:15Lasting months, years or even decades.
51:21Temperatures plummeted.
51:23Plants withered.
51:25Dinosaurs disappeared.
51:30The great lizards were gone.
51:35But the show was far from over.
51:40The tremendous calamity at the end of the Cretaceous had cleared the global stage.
51:45Though this time, not simply for the next scene in the great drama of life on Earth.
51:51But for the appearance of the Australia we know today.
52:21The world of Ontario is a extraordinary nightmare
52:22The world with the world's greatest plan of life on Earth.
52:23The world's greatest plan, not only for the next scene in the world in the world in the world in a world.
52:25We'd run into a world's greatest plan.
52:26We're very excited.
52:27The world's greatest plan.
52:28That's a world's greatest plan.
52:29We're very excited.
52:31The optimist has been in the world's greatest plan.
52:32The world's greatest plan of life on Earth.
52:34We've made three opportunities for the most possible people.
52:36We've renewed vision of the world outside of Earth.
52:38Now, what did we see?
52:40Are we realised?
52:41You've been with aomancy.
52:43The most abrir is very excited to get around that realise of us.
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