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Attenborough and the Giant Sea Monster
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00:08I'm on the south coast of England, in what is known as the Juratic Coast.
00:15150 million years ago, the land was ruled by dinosaurs.
00:22But the oceans were dominated by a mysterious sea monster.
00:35Its remains are very rare, but some have just been discovered in the cliffs behind me.
00:45And now fossil experts are working to unearth this extraordinary find.
00:52No one's ever done this before ever, extracting a giant skull halfway down a cliff face.
00:58This colossal creature is called a pliosaur.
01:05But little is known about these prehistoric giants.
01:11What an extraordinary, terrifying thing.
01:15Together with a team of scientists, we will use new technology to discover more about this enormous marine reptile.
01:26I have no doubt that this pliosaur was the T-Rex of the seas.
01:32Comparing it with animals alive today, we can deduce a great deal about their sheer strength.
01:42This pliosaur has a bite force that's about twice the great white shark.
01:46Well, that's unimaginable.
01:50Could this be the greatest Jurassic predator that ever lived?
02:12Britain has a wealth of fossil sites, but perhaps none are quite so famous as this, the Jurassic Coast.
02:30I've been collecting fossils since I was a boy, and I haven't yet got tired of it.
02:38These days you're supposed to wear glasses for safety.
02:44And if you wouldn't know a locality, you'll begin to recognise the sort of block that might contain a fossil.
02:51And this rock was split earlier to make it easier to show you.
02:56And if I can hit it quite hard about there.
03:10What about that?
03:12Is anything more beautiful than that?
03:16Fantastic.
03:18Finding even the smallest fossil is a thrill.
03:21But discovering something much larger can be an unforgettable moment.
03:27And that is exactly what happened to a fossil enthusiast who was walking along a beach near Kimmeridge Bay in
03:34Dorset one morning.
03:35I just found something quite extraordinary.
03:39It's the jaw of a massive pliosaur.
03:44It's enormous.
03:46It's a massive pliosaur.
03:48It's the best fossil I've ever found.
03:51It must have just come out of a cliff up there somewhere.
03:56Renowned fossil expert Steve Etches was called in, and he realised immediately that this find could be hugely significant.
04:05Look. Look at those teeth.
04:08Look, it's a tooth there. Look.
04:10Let's have a look at the front.
04:11You can walk along here for hundreds of times and not find anything, and then occasionally you'll hit the jackpot.
04:18And this certainly is the jackpot.
04:23It's the snout of an enormous pliosaur skull.
04:28And Steve suspects that the rest of the head might still be embedded in the cliff above.
04:36But he needs to work fast before the whole thing tumbles into the sea and is lost forever.
04:44So he quickly gathers a team of experts, including fellow fossil hunter Chris Moore.
04:52It's day one of the digs.
04:54Steve and team diggers are up on the cliffs, and they're putting the net down to stop any loose rock
05:02rolling down and hitting us.
05:04And then we'll go down and expose the skull.
05:09Steve and Chris have worked together for decades.
05:14But this is the biggest challenge they have ever faced.
05:25The location of the skull, high up on a disintegrating cliff face, makes it very difficult to reach and even
05:32harder to work on.
05:39These rocks were once mud on the sea floor, in which the remains of prehistoric marine creatures were buried.
05:52Over millions of years, the continents shifted.
05:56The seas receded.
05:59And today, as these cliffs erode, fossilized skeletons are revealed.
06:07The jaw is there, and the idea is to actually cut this down vertically, and then we form a platform
06:13where the fossil is.
06:19I've known Chris and Steve for many years, and I can't wait to join them and find out how they're
06:26getting on.
06:31Here we've got a live feed to them actually digging halfway up the cliff face.
06:36What's happened so far, the tip of the snout's already come out and been recovered, so the rest of it
06:43is going into the cliff.
06:44What exactly are they doing there?
06:47At the moment, they're using tinfoil to try and protect the exposed piece of jaw.
06:53In case something falls on and break it.
06:56Yeah, yeah, yeah.
06:56And then they're also using a superglue to consolidate the crumbly teeth and parts that have been weathered over millennia.
07:05And they're hanging by ropes there?
07:07Yes, pretty much in the center of the cliff.
07:09Dear me.
07:10Pretty dangerous stuff, this.
07:11Yeah, yeah, it really is.
07:14After you've worked there for a few hours, it becomes a bit more natural.
07:17Yeah.
07:17And you concentrate on the actual digging.
07:20You must be pretty sure that there's something there to put this amount of effort into it, really.
07:25Oh, positive there's something there.
07:27It's beautiful.
07:28It's a beautiful specimen.
07:29Is it?
07:30Yeah, amazing.
07:33But what can this spectacular find reveal about the lives of these mysterious sea creatures and the world they inhabited?
07:46In the late Jurassic, Europe was an archipelago of islands, much closer to the equator than it is today.
07:55Its seas were warm, shallow, and teeming with life.
07:59And in these waters, underneath my feet, lurked the ultimate marine predator, the Plyosaur.
08:22Unlike dinosaurs that lived on land, these colossal marine reptiles spent their whole lives in the ocean.
08:33They're thought to have been around 10 meters in length.
08:38That's about the size of a double-decker bus.
08:42They had long, broad flippers, short, strong necks, huge heads, and enormous jaws.
08:58But there's still a lot we don't know about these great sea monsters.
09:03Which is why this new discovery is so important.
09:08Steve believes that the entire Plyosaur may still be inside the cliff.
09:15But it's the skull on which he's concentrating.
09:21A skull can reveal more about an animal than any other part of its skeleton.
09:31Finding a complete specimen is rare.
09:34But it can tell us a great deal about how the animal lived.
09:45It's quite hot and thirsty work.
09:48Steve and Chris think they will have about three weeks to dig the fossil out before the storms of late
09:55summer come.
09:59This is a learning curve.
10:00I thought, stupidly, that it wouldn't be quite as hard as this.
10:06We're probably over a meter in.
10:09There's the skull there, just behind me.
10:13It's up to us now to get it out without any damage.
10:18If the skull is successfully extracted, it will be taken to the Etch's Collection Museum in Kimberage,
10:25which was founded by Steve in 2016,
10:29and now contains nearly 3,000 fossils from the Jurassic period.
10:36This was where the Plyosaur's snout was brought to be assessed.
10:42And I've come here to learn what Steve has found out so far.
10:47What an extraordinary, terrifying thing.
10:52Huge teeth.
10:53They are. They're massive.
10:55These big fang-like teeth that come up.
10:58And they interlock.
10:59Yes, they do.
11:00So how far do these teeth extend?
11:02They come right up here.
11:03Is that characteristic of this?
11:05Yes, typical Plyosaur.
11:07It's trihedral teeth.
11:08They've got two sharp cutting edges and then a flat face on the inside.
11:13They must have used that to rip apart Ichthyosaurs.
11:17Ichthyosaurs, Plesiosaurs as well.
11:19We've got evidence in the museum, because they've got sub-triangular teeth.
11:22When they bite into a bone, they leave a very distinctive tooth hole.
11:27Steve's collection contains a limb bone of a Plesiosaur,
11:32another large marine reptile, which has bite marks on it
11:37that exactly match the size and shape of Plyosaur teeth.
11:43What a godsend it is that the teeth are triangular,
11:46so that you're able to then identify prey.
11:48Oh, yeah.
11:49Just as much as you can identify the one that was the predator.
11:52That's right.
11:53That's pretty unusual to find teeth in position.
11:55It is.
11:55This is the first Plyosaur I've ever seen with actually closed jaws.
12:00It is extraordinary.
12:01Mm.
12:02It is quite extraordinary.
12:04And there is another unusual feature on this snout.
12:09So let me show you the other side.
12:11I'll spin it round.
12:13Oh, gosh, there's a lot of stuff here.
12:15Oh, yeah.
12:15And these holes here.
12:18While I think these are sensory pits, they're all on the snout.
12:21If you look at them, they go, see, they strike back in at that angle.
12:24You know?
12:25Yes.
12:25They're sensory pits for picking up its prey, I'm pretty sure.
12:28Pretty impressive beast.
12:30Astonishing.
12:30Mm.
12:31But exactly how did these sensory pits help our Plyosaur to hunt?
12:42These days, we have equipment that can help us answer such a question.
12:51We take the snout to the University of Southampton, which has some of the most powerful CT scanners in the
12:59UK.
13:00Hold that.
13:01That's it.
13:02And we upright it.
13:04Dr. Katie Rankin is a specialist in scientific imaging.
13:10She takes thousands of X-rays through the fossil that reveal its internal structure.
13:18But even with such high-tech equipment, the process is not straightforward.
13:24The snout was very challenging.
13:27A typical CT scan can be around an hour.
13:31In this case, because the fossil was very, very dense, it actually took very, very long.
13:36So it took about five days.
13:38Five days?
13:39Yes.
13:40With the scan finally complete, paleobiologist Dr. Neil Gosling is looking for clues about the sensory abilities of our Plyosaur.
13:50So what does this scan tell us?
13:52I've taken the CT data, and we can rack our way through this stack of images, and we can see
13:58all of those internal structures which otherwise wouldn't have been revealed to us.
14:03And there are some things which are, I think, quite exciting.
14:07We've got these little structures in red, and I had to do these, each one slice by slice, dot by
14:11dot, because there's lots of imperfections and holes in it.
14:14But these are continuous, and I think these are blood vessels, little branching blood vessels.
14:20Oh, come on.
14:22You're really telling me this block of stone can show blood vessels?
14:26Yes.
14:26And what I think we've got here are actually branches of the trigeminal nerve, and these are the sensory nerves
14:33in your face that allow you to feel fingers dancing over your cheeks and what have you.
14:38But if you're in water and you've got these sensory pits, you can detect changes in pressure.
14:44That's going to give you an advantage in what might be murky water where your eyes aren't working so well,
14:49so you can always be sure that you're going to catch your next meal.
14:52It's fantastic.
14:54Knowing how these senses worked, we can start to build up a picture of how our pliosaur hunted.
15:05Its prey, ichthyosaurs, reptiles much the same shape as a modern dolphin, and similarly fast and agile.
15:19The sensory pits found on our pliosaur's snout may have acted like miniature pressure pads, detecting the turbulence produced by
15:31ichthyosaurs as they swam through deep water.
15:36In effect, our pliosaur was able to stalk its prey even in the darkest depths just by using its skin.
15:48There are animals today that have similar sensory systems.
15:54Crocodiles have over 9,000 pressure receptors which are concentrated on their snouts, each one of which is thought to
16:03be ten times more sensitive than a human fingertip.
16:15Two weeks into the dig, and the work is proving to be even harder than anyone was expecting.
16:38The last couple of three days have been, oh, I think it's been sapping everyone.
16:43I think it might be a tooth, but it's got no crowns.
16:46Let's have it.
16:47Let's have it.
16:47All right.
16:48I wouldn't like this with David Attenborough.
16:50I bet you'd give them a little lip, did you?
16:52Yeah, but I like him.
16:53Oh, all right then.
16:55Being 11 metres up a cliff is one challenge.
16:59Digging through incredibly hard rock with air tools.
17:04Every lump is hard won.
17:07But at last, there's a breakthrough.
17:12There's something under there which is huge.
17:14Here you've got the jaw showing, and this one's heading back this way.
17:20It's going to be the underneath of the skull.
17:22There's a vertebrae there.
17:23There's another vertebrae there.
17:26Finding these bones confirms that the entire skull really is inside the cliff.
17:32It's nice to actually see something.
17:34You feel like you've been rewarded a bit.
17:37What Alex is doing, he is chipping out a loose tooth.
17:41Hang on, that's the crown.
17:42Yeah.
17:43Oh, that's interesting.
17:44Yeah, keep going.
17:45This is part of the root, and there's a pulp cavity there.
17:49That tooth will be probably about ten inches long.
17:54Oh, the thunder's coming.
17:55Oh, look at that.
17:56Just as the dig is revealing further exciting finds...
18:00Go on, guys.
18:01Yeah, come on, Chris.
18:03Because we've got a lot to do.
18:04We've got to get you all up.
18:06Conditions become treacherous, and the rope safety team decides
18:10that it's too dangerous to continue.
18:14Now it's rained, this lithified mudstone has turned like a slippery clay.
18:19It's lethal.
18:23There's certainly no way now, with our stopping now,
18:26that we're going to get it done in those days left.
18:31The weather may be against them, but finding a pliosaur tooth is a real stroke of luck.
18:38It could also help us understand more about the type of prey our sea monster could eat.
18:47Back in Southampton, the scan has revealed something even more intriguing about the pliosaur's snout.
18:56These teeth are extraordinarily well-reserved, aren't they?
18:59Is there new information that we can get from this?
19:02Well, from the CT scan, if we take it back again so we can expose the teeth,
19:07these are large pointed teeth, and these are really well adapted for grasping slippery fish,
19:15but this is on an order of magnitude larger,
19:18which would have allowed it to eat all sorts of prey
19:22that are swimming around in the ancient Kimmeridge Bay of the time.
19:26Were the teeth permanent, or were they replaced?
19:30As we move it back through, we can see that we've got individual teeth almost all the way along.
19:35However, in one place, we've got this little tooth here, and this is a replacement tooth.
19:41The thing that most animals die of is that their teeth have worn out and they can't feed anymore.
19:46And if you are a large predator and you are catching large prey, you might lose teeth relatively frequently.
19:54Well, this isn't such an issue if you can replace your teeth multiple times throughout your life.
20:00Not only were its teeth replaceable, but they were also shaped differently.
20:06Long and sharp towards the front of its jaws, more hook-like at the back.
20:13This deadly combination meant that the pliosaurs could feed in a variety of ways,
20:19from grabbing large sharks and squid to gripping smaller, slippery fish.
20:29But pliosaur teeth have another special feature which scientists are only just beginning to understand.
20:41These are exact replicas cast from the teeth of our own pliosaur.
20:48As you can see, they're very large, and also trihedral, three-sided.
20:56If we look closer at this one, we can see it has very distinct ridges, known as striations, that run
21:05vertically down the tooth.
21:09A recent study by scientists in Australia investigated why pliosaur teeth had these ridges.
21:18And I'm keen to test some of these theories myself.
21:23The research proposed that when the pliosaur plunged its teeth into its victim,
21:29these tooth ridges could have helped to not only pierce the flesh, but also prevent a vacuum forming.
21:37So I am going to try and imitate our sea monster's bite, using the replica teeth and a block of
21:46ballistic gel,
21:48an artificial equivalent to animal flesh.
21:53This pliosaur tooth has had its ridges entirely removed.
21:58Without its striations, the surfaces are now completely smooth and flat.
22:04So firstly, if I plunge this smooth tooth into the gel...
22:15That did feel difficult to push the tooth in and pull it out again.
22:20But now, if I repeat the same movement with the rich tooth, in theory, it should feel easier.
22:29Smoothly in.
22:33And now pull it out.
22:35No bother.
22:37Well, that certainly felt significantly easier.
22:42To get a more scientific opinion, we test the teeth at the University of Bristol.
22:48And the results indicate that the ridge teeth do require less force to be pushed into the gel.
22:59While this area is new to science, it seems that the theories are on the right track.
23:06The ridges on its teeth could have enabled the pliosaur to more easily capture its prey underwater
23:13by allowing it to swiftly and repeatedly bite down, ensuring a quick, successful kill for this Jurassic Sea monster.
23:29Three weeks into the dig, the weather is holding.
23:34And now the biggest question for Steve and Chris is how to lift the skull off the cliff.
23:40I reckon we'd be taking out a big slab.
23:42One piece?
23:43Yeah.
23:44Cut it underneath?
23:45What, cut underneath?
23:46Yeah.
23:46All the way through?
23:47Yeah.
23:48I can't see any other way of doing it.
23:50If we do it any other way, it's going to just crumble up.
23:53What do you think?
23:54I think I'm going home and not coming back.
23:59Luckily for Steve and Chris, friend and local farmer Rob Vernacom has been devising a solution.
24:09He's building a crate which will be lowered down the cliff into which the skull will be maneuvered and then
24:16hauled up to the top.
24:19Yeah, I'm actually a farmer by trade because of all the machinery and building that's involved.
24:26Effectively, I'm a self-taught engineer, but it is a massive challenge from an engineering point of view.
24:34Rob believes that the crate will enable them to get the skulls safely to the top of the cliff.
24:40The theory is that whatever angle the skids are, as it comes up the cliff, the box stays level to
24:47protect the fossil because we're trying to keep the fossil as level as possible.
24:52The big day finally arrives and a local army of helpers is assembled for this crucial stage of the operation.
25:03And Steve is feeding the pressure.
25:06With the best way in the world, it looks like it's all going to function, but the risk is immense.
25:10You know, what happens if it just actually turned on its side?
25:13There's a lot of things that could go wrong, so it's a risky sort of time.
25:19This is one of the largest and best-preserved Plyasaur skulls ever found.
25:25So the stakes are very high indeed.
25:36When it comes down, we've got to get that aligned and we've got to get that jaw, that skull, inside
25:41that box.
25:41And we've got to be really careful that that sled has got a metal bar and as it comes down,
25:48it doesn't hit the nose.
25:52No one's ever done this before, ever.
25:54Extracting a giant skull halfway down a cliff face.
25:59The crate must be lowered into position with great precision if the skull is not to be damaged.
26:07The position it's coming down in, it's almost going to glance the side of the skull.
26:14Stop!
26:14Stop!
26:16Stop!
26:17So somehow we've got to manually try and move the whole sled over.
26:23I think we can afford to do 30 centimetres lower and no more.
26:29After weeks of back-breaking work, emotions are running high.
26:34Down!
26:35Come on!
26:36Quick, quicker!
26:38This moment's really fraught.
26:42We've got one skid just about glancing the side of the skull and we've got to try and pull it
26:48out now to get it over the edge.
26:50Very slowly, six inches.
26:53One clumsy move and the skull could be smashed.
27:03Oh my...
27:04Pull, pull again!
27:05That's all right, that's all right.
27:06Missed it.
27:07We've done it.
27:07Stop, stop!
27:09It's all pretty stressful.
27:12Every part of this is really, really stressful.
27:15After quite a few hours, we've got it into position.
27:18We haven't knocked the end of the snout off so far and it's all ready to go.
27:25But the next stage looks even more risky.
27:28Just retreat from the edge and we're going up the ropes now.
27:33Al and Steve are going to go up to the hole and attach the winch and then start the process
27:41of slowly dragging it into the box.
27:45Shifting a fossil that weighs over half a ton is really dangerous.
27:53It's moving.
27:54It's very nervous and it's very tense.
27:56So let's see how it goes.
28:04Oh, go on.
28:06Good.
28:07That's better.
28:08That's fine.
28:10Right, I think slide it straight in.
28:14Steve, is it okay?
28:15Has it come off okay?
28:17Well, we're losing a bit of it, but you can't hold it, mate.
28:20Go on.
28:22Go on.
28:24That's on it.
28:25There you go.
28:25Right, there you go.
28:27Good.
28:29That's well in there.
28:30It's right in the case now.
28:32Hey, the fossil's in.
28:34Brilliant, brilliant.
28:35We're all tuning here.
28:36Well done, well done.
28:37Well done, everybody.
28:39Right, well done.
28:41Brilliant.
28:42We've overcome a lot of problems to get this far, and we've done it by the skin of our teeth.
28:48The skull, at last, is in the crate.
28:51Take up the sack again.
28:53Oi!
28:56But shifting it carelessly, let alone dropping it, could be disastrous.
29:02Come over a bit.
29:04There'll be six ropes coming up to be able to lift it and hold it steady.
29:09Hopefully.
29:10With the tide coming in and the sun setting, we couldn't cut it at any point.
29:18Okay, right.
29:20Whoa, whoa, whoa, whoa.
29:24Finally, the skull is safe.
29:27Brilliant, Rob.
29:28Well done.
29:29Well done.
29:33Yeah.
29:35It's amazing.
29:38It's a dream come true.
29:39And I'll tell you what, I don't think anyone in their right would ever believe we could have done it.
29:44Three weeks ago, it was buried in a cliff face.
29:47Found the top food chain predator, and now we're bringing it back to life.
29:50And this would be one of the best that's ever been found.
29:53Hey!
29:54Hey!
29:55Good on you.
29:56Oh, God.
29:57No, none of that.
29:58Good on you.
29:59Get off!
30:00You little devils.
30:01Oh, dear, oh, dear.
30:04It's out.
30:06The next day starts.
30:16The skull is transported to Steve's workshop.
30:21Ready?
30:22Go.
30:25Right up.
30:27Oh, my God.
30:29The mudstone's cracked and dried.
30:31Of course, what it's done is just cracked the bone as well.
30:34Jeepers, creepers.
30:35You'll be fine.
30:36Oh, yeah.
30:38I can see this is the biggest jigsaw going.
30:41Luckily, you're a young man, aren't you?
30:43Yeah, yeah.
30:44Plenty of time.
30:45Yeah, plenty of time.
30:48The painstaking task of removing the stone from around the skull
30:52so that it can be examined in detail
30:57can at last begin.
31:00After the heavy work of the dig,
31:03this stage requires a delicate touch.
31:07First, Steve removes the rock surrounding the fossil
31:11so that the fragile areas of the skull can be strengthened.
31:16Then, using an air abrasion tool,
31:20he starts work to reveal the more intricate details
31:23about the anatomy of this extraordinary animal.
31:27This giant sea monster,
31:30after 150 million years,
31:33finally begins to emerge from the rock.
31:40And I have the privilege
31:41of coming to see this whole skull for the first time.
31:47So, here it is.
31:50And it's enormous.
31:53I am meeting Dr. Judith Sassoon,
31:57the paleontologist
31:58who has studied pliosaur specimens for decades.
32:03Does it still take your breath away as it takes mine?
32:06It is a most astonishing specimen, David.
32:08I'm very pleased to be part of the work on it.
32:15What insights can Judith give us
32:17into the life of this ancient monster?
32:24How's it coming along?
32:25What sort of detail it can get from this
32:28which you never knew before?
32:29Steve Etches has been working on it now for several months
32:33and has made some fabulous progress.
32:36We're seeing, as it's being prepared,
32:39gradually more and more detail being revealed.
32:42So far, we have some information about its senses.
32:47Really? Was that outside good?
32:49There are indications that, in fact, it could have been.
32:55The eyes themselves were quite important for this animal.
33:00One of the reasons is the position itself.
33:04The eyes are on the side of the head,
33:08more or less in the middle,
33:10so not too high and not too low.
33:15This important feature of the skull may suggest
33:19how are pliosaur hunted in the open ocean.
33:27The position of the eyes in living animals varies
33:31according to the way in which they hunt.
33:35Dolphins are pursuit predators.
33:40Their eyes are placed on the side of their heads,
33:43which gives them panoramic vision,
33:48enabling them to attack their prey with great accuracy.
33:55Ambush predators, such as crocodiles,
33:57have eyes higher up on their heads.
34:03So they can remain just below the surface
34:06with only their eyes above water
34:08and judge when to attack.
34:16Our pliosaur seems to have had something in between.
34:21With an eye position that not only enabled it
34:24to pursue prey through the water with accuracy,
34:28but alternatively, surprise it by attacking from below.
34:35And there is another remarkable feature
34:38which could tell us more
34:39about where our sea monster may have hunted.
34:43We talked about eyes.
34:45There's also another interesting structure,
34:48which is the parietal eye.
34:51In many reptiles, this still exists.
34:55When it is present in terrestrial animals,
34:58it has a full eye structure like the lateral eyes
35:02and is light sensitive.
35:07The parietal eye on the top of the head
35:10is something of a puzzle.
35:13It's known as a third eye
35:15and is still found in a few living species.
35:18It apparently helps an animal to regulate its body clock.
35:28The pliosaur's parietal eye is thought to have had a lens,
35:33a cornea and a retina.
35:36Although its exact function is unclear,
35:39it may have enabled our sea monster
35:41to gauge which way was up when swimming at depth
35:46and potentially navigate the deeper hunting grounds.
35:52What other questions would you wish to the skull to provide answers for?
35:57I've already made some measurements on this animal
36:00and the proportions do seem to be different
36:03from other pliosaurs that we know.
36:06The skull is quite long-snouted,
36:10but the position of the nose and the eye
36:14and also of the crest suggests that it is something else, something new.
36:21A new species of pliosaur?
36:23Of pliosaur, yes.
36:24A new species? Really?
36:26I think it could be, yes.
36:30The revelation that our pliosaur could be a new species
36:34is truly exciting.
36:42There are only eight recognized species of pliosaur.
36:49And this skull is certain to provide new scientific data
36:54on the evolution of these mysterious marine reptiles.
37:00I have to say, you take my breath away,
37:03the detail which you can deduce.
37:06It is mind-blowing, I think,
37:08and that's what paleontology is about.
37:10I used to think it was just a question of finding a fossil
37:13and digging it out and saying how nice it was.
37:16You made it sound rather different.
37:23In recent decades, huge advances have been made
37:27in our ability to study prehistoric animals.
37:31And we can now investigate the predator power of our pliosaur
37:36in more detail than ever before.
37:43Paleobiologist Dr. Andre Rowe is a world-leading expert in 3D visualization of fossils.
37:51The first thoughts, this thing is absolutely massive,
37:54and I will also add that the level of preservation is amazing.
37:58There's this common misconception that fossilization is just this really common thing,
38:02and we get these complete skulls all the time, and that's sadly not the case.
38:06This is actually a one in a million, maybe one in a billion type specimen here.
38:12Using the latest technology, Andre is carrying out the world's first surface scan of a pliosaur skull.
38:24So right now we're capturing basically hundreds of thousands of images all at once.
38:29It's essentially putting together a big 3D jigsaw puzzle.
38:32The end result is a really nice-looking 3D model, which we can use for biomechanics, studying the anatomy.
38:39I think we'll be able to unlock a lot of mysteries about what these sea monsters were doing.
38:43And I'm really excited to see where it takes us.
38:49Once the scan has been finalized, I meet Andre at the University of Bristol to discuss his findings.
38:58Has he seen anything in the skull structure that shows our sea monster had the power of a truly deadly
39:06predator?
39:07There's some massive openings back here along the jawline, and that's good for muscles to attach and bulge out.
39:14There'd be a mussel goat running through there.
39:18Yes, we have the pterygoid mussel group, which is in a lot of big dinosaurs, and it's integral to having
39:24a really strong bite.
39:25And we've hypothesized that this particular pliosaur is kind of the apex predator in the Jurassic ecosystems it was living
39:32in.
39:32In the seas? Yes.
39:34Now this, of course, is not a dinosaur, but neither is it a modern reptile.
39:38But it does look a lot like a crocodile, doesn't it?
39:41Yes. Well, we have this process called convergent evolution, where a lot of animals will adapt this similar-shaped skull
39:48or similar trends throughout their evolutionary history, even if they're not closely related.
39:53That's because having those similarities can give you a lot of advantages.
39:56But in terms of this pliosaur, it's got that kind of streamlined skull that's kind of broad in the back.
40:02It's very triangular-shaped, and a lot of marine reptiles kind of have that skull shape.
40:06I think that it's good for swimming quickly and ambushing prey.
40:10Does this skull give you any information about what animals' prey might have been?
40:15The animal would have been so massive that I think it would have been able to prey effectively on anything
40:20that was unfortunate enough to be in its space.
40:23A popular hypothesis is that these animals were actually ripping off the limbs of other animals that disabled them from
40:29swimming away, and then kind of going in for a kill.
40:31So this is really a top predator?
40:34Yes. I have very little doubt just judging from how massive that skull is. I don't see what could have
40:40possibly hurt it.
40:41What size is that, actually?
40:43So the actual skull itself clocks in just a little under two meters.
40:47Two meters longer than I am?
40:49Oh, it's quite a big boy, and that's just the skull.
40:51The dimensions of a fossilized skull enable us to estimate the overall size of an animal when it was alive.
41:00And based on Andre's measurements, our pliosaur could have been up to an astounding 12 meters long.
41:11Just from the sheer size of it, just from looking at this animal and how big those pterygoid muscles would
41:16have been at the back of the jaw, the animal would have delivered a devastating bite, no doubt.
41:22A powerful bite is vital to the success of any marine predator.
41:30Scientists are able to estimate how much force an animal can exert when biting into its prey.
41:37And great white sharks have one of the strongest bites, at around 10,000 newtons.
41:50But how do you work out the bite force of a creature that became extinct millions of years ago?
41:57Professor Emily Rayfield is a world-renowned paleontologist who specializes in skeletal mechanics.
42:05Using the model created by Andre, Emily has assessed the bite force of our pliosaur.
42:13So this is a 3D print, a model.
42:15It's not full size, though it's just over a third of the size of the actual animal.
42:20These large openings are the spaces in the skull which would have been filled with jaw-closing muscles.
42:26So you can estimate the force of the bite from the size of those muscles?
42:32Exactly, yeah, we can get an estimate of that from here.
42:35We know that muscles of a certain size, a certain area, are capable of generating a certain amount of force.
42:45Saltwater crocodiles have got the largest ever bite force measured, and they're up to about 16,000 newtons.
42:54And these?
42:54So our pliosaur here, from the estimations that we've made, has a bite force that's about twice the size of
43:00that of the largest saltwater crocodile that's ever been measured.
43:04And it's in the region of around 32,000 newtons.
43:07So this is the most powerful biter in the sea that there has been, or that we know of?
43:14That we know of, absolutely, yes, definitely.
43:17If you're looking at kind of statistics in terms of car-biting metrics, I'm pretty sure it could probably bite
43:23through a car.
43:24So it's a monster?
43:25Absolutely.
43:35The evidence gathered from the skull so far suggests that this pliosaur had the jaws, teeth and senses of a
43:45highly successful hunter.
43:50It's long snout, short neck, and streamlined skull enabled it to move easily through the water.
43:58But what else helped our enormous sea monster to power through the Jurassic Seas fast enough to catch its prey?
44:07The pliosaurs were unique in the natural world, as they had four almost identical wing-like flippers.
44:17How pliosaurs used their flippers has been debated by paleontologists for decades.
44:23Some believe that they moved using a sort of rowing stroke, like oars in a boat.
44:30While others argued they used a flight stroke, seen in animals such as sea turtles.
44:38But in recent years, scientists have been able to use computer modeling to finally solve this mystery.
44:46And it appears that these giant sea monsters swam in a way that is surprisingly similar to a very different
44:55type of animal.
44:56One that is alive today.
45:04One that is alive today.
45:07One that is alive today.
45:07Penguins may appear somewhat clumsy as they waddle around on land.
45:12But once they're in the water, they move very differently.
45:17These are Humboldt penguins, and they're excellent swimmers.
45:24Their streamlined body shape and their oily feathers enable them to reach astonishing speeds of up to the sea.
45:30Up to 30 miles an hour.
45:32But a key factor behind penguins' speed are their flippers, which underwater act like propellers, driving them forward and increasing
45:42their speed dramatically.
45:45In slow motion, you can see that the penguins are using a lift-based underwater flight movement, twisting their wings
45:55as they flap and propelling themselves forward on the upstroke as well as the downstroke.
46:03As strange as it may seem, it's thought that pliosaurs would have moved in a very similar way.
46:10But of course, pliosaurs were enormous, and most large animals are relatively slow-moving.
46:18So, as an apex predator, how could this huge creature maneuver itself fast enough to catch its prey?
46:27To find out, I've come to the Hydrodynamic Laboratory at Imperial College London,
46:34where Dr. Luke Muscutt is studying the locomotion of pliosaurs using a rather unusual research tool.
46:42How did you first become interested in the way that pliosaurs swam?
46:48It's the only animal that we know of that has four large flippers.
46:53So, the question is, how did they use them?
46:56When we're trying to understand an extinct animal, the first thing we need to do is look at the fossils.
47:02So, we understand the shape of the bones, how the bones fit together.
47:06The fossils of the pliosaurs show that the flippers were very much like wings.
47:12So, what I found was that the hind flipper can actually operate at a much higher thrust and at a
47:18much higher efficiency
47:19because it's utilizing the wake of the flipper in front of it.
47:24We can see a similar effect in the flight of migrating birds such as geese.
47:32When geese are flying in formation, each bird benefits from the uplift created by the one in front of it,
47:41so that they fly in a very energy-efficient way.
47:49So, you can think of the pliosaur as almost two birds, one flying behind the other, and the back one
47:55is benefiting from the one in front.
47:57That's an extraordinary parallel, yes.
47:59The hind flipper has increases in thrust and efficiency of up to 40%.
48:04So, this would have increased the swimming speed that pliosaurs would have been able to achieve,
48:10and increase the number of different things it could eat.
48:14To take his research to the next level, Luke has built a robot to study the swimming pattern of pliosaurs
48:21more accurately than ever before.
48:23So, what more information do you think you can get from this model?
48:28This robot enables me to test the complete animal.
48:33How fast something can move is an absolutely critical part of what that animal is.
48:39And it tells us what animals it could have eaten, how far it might have been able to travel.
48:46All sorts of questions come back down to its locomotion ability.
48:52Have you estimated the speed that this might produce?
48:56Well, I've only finished building this yesterday, so so far I haven't actually run the experiments yet.
49:02If you'd like to have a go, you're more than welcome to...
49:04Oh, show me.
49:05So, if you just move this joystick sort of upwards further...
49:09So, this is how the pliosaur would have swam.
49:13The flippers move primarily up and down.
49:16It's much more like a bird flies.
49:20Luke and his team set up the robot for a test swim,
49:25and they interest me with its maiden voyage.
49:29Would you like to take the control?
49:32There we are. It's off.
49:35Really got some high acceleration there.
49:37I suppose, actually, that's only a model, but if it was full-sized, it would be going quite fast.
49:42Indeed. You can just imagine it chasing after a smaller igtheosaur.
49:48Luke's research is so new, it's yet to be published.
49:52But it's helping to provide a new perspective on these extraordinary animals.
50:03Large marine predators like orcas can swim at great speed through the ocean.
50:12What speed might our pliosaur, with its four flippers, have been capable of?
50:20Estimates suggest that they could have accelerated up to 30 miles an hour,
50:25making them one of the fastest animals in the Jurassic Seas.
50:38This skull is not only helping us to understand more about the lives of these giant sea monsters,
50:45but also allows scientists like Dr. Andre Rowe to visualize the Jurassic World as never before.
50:54So often, I've been involved in looking at fossil skeletons and the skull,
51:00unless the skull is there, you're really missing an awful lot of information.
51:04We are lucky to find this as the first thing.
51:07Yes, I am very biased since I study feeding and teeth,
51:10but I think the majority of the information about an animal you can get from its skull.
51:14The brain, the teeth, what it was feeding on,
51:17its maximum body size if you have the whole skull.
51:20It's just a treasure trove of information, and we're very fortunate to have the whole thing.
51:24One of the reasons why I love the UK is because it's got such a great collection of marine reptiles.
51:30Delighted to hear it.
51:31I mean, in America, we've got our big tyrannosaurs and our triceratops, but the UK is great for marine reptiles.
51:37Well, we did discover the dinosaurs.
51:38Yes, the science of paleontology did originate here.
51:41How would it compare with T-Rex?
51:43I imagine it would be pretty comparable, and they were kind of both the respective apex predators and their ecosystems.
51:50So, I have no doubt that this was sort of like an underwater T-Rex, if you will.
51:55Okay, let me ask you the million-dollar question.
51:58In a battle between T-Rex and our pliosaur, who's going to win?
52:05As much as it pains me and brings a tear to my eye to admit it, I think my T
52:09-Rex is going to lose this fight.
52:12And then millions of years later, an American paleontologist will envision the scene and break down into tears.
52:21Bringing an enormous predator back to life after 150 million years is no easy task.
52:30But restoring this giant skull is a labor of love for Steve and his team.
52:38Almost a year after the skull was discovered, I returned to Kimmeridge to see how they're getting on.
52:46My goodness.
52:49It is absolutely magnificent.
52:52It's astonishing.
52:54It's bigger than a T-Rex.
52:56Is it? Yeah, yeah.
52:58Like the skull? Yeah, bigger than any T-Rex ever found.
53:01David, now what we've done, since you've come here last, is I've air-penned off all the mudstone and then
53:09air-braided it.
53:10Now the air-braided machine cleans out all these little voids and you see every little detail.
53:15Every suture where the bones join together, you can see every detail.
53:19That's what we really wanted.
53:20So the teeth here have been basically tumbled on the beach and the shingle had worn away all the crowns.
53:28So we're going to do a bit of dentistry on them.
53:30So we've got this tooth which has been scanned and then we're going to increase or decrease it and then
53:37add all the teeth back in position.
53:40Show people what it actually looked like.
53:42You must feel looking at this.
53:44I mean, I know it was a huge amount of work to get it out.
53:48We never thought we'd get it, to be honest. I'll be honest with you.
53:51Well, it's certainly a triumph.
53:55Yeah, quite an emotional moment for everyone.
53:57I'm sure.
53:59A sensation.
54:06Once the pliosaure's dagger-like teeth are added, the picture is finally complete.
54:19Our journey of discovery has shown that this sea monster was one of the greatest predators the world has ever
54:27seen.
54:29And we can now visualize more accurately than ever how it may have hunted in the Jurassic Seas.
54:48Icthyosaurs, swimming in groups along the coast.
54:55Concentrating on hunting their prey.
54:58Unaware that they themselves are being stalked.
55:06On their trail, our pliosaur uses its highly-tuned senses to launch an attack.
55:21In the chase, its four flippers, each two meters long, drive it through the water at great speed.
55:33Splitting the shoal, it isolates its target.
55:40Our sea monster's primary weapons are its 90 razor-sharp teeth.
55:48With which it slices through its victim's flesh.
55:54The impact alone may have been enough to kill.
56:01But with a bite force twice the strength of any animal living today, its prey had little chance of survival.
56:30From a chance discovery on a beach one morning, to the painstaking restoration of such a rare and impressive specimen,
56:38the story of this fossil is one of skill, dedication, and of fascinating scientific discoveries made along the way.
56:49We've been given a unique insight into the life of our pliosaur that swam in the Jurassic Seas 150 million
56:57years ago.
56:58But we're also reminded that there is still so much to learn about these extraordinary prehistoric animals.
57:10And I, for one, will never tire of discovering more.
57:27Catch a breath of icy air over on BBC Two now, Nature at the Extreme, brand new series Wild Scandinavia
57:34continues.
57:35Meanwhile, the wait is over here on one. Is it time for Elliot to find out who he really is?
57:40The new series of The Tourist, next.
57:43Find out what you're next!
57:43A
57:44A
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