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Nature
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AnimalsTranscript
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00:09I'm on the south coast of England,
00:11in what is known as the Jurassic Coast.
00:16150 million years ago,
00:18the land was ruled by dinosaurs.
00:23But the oceans were dominated by a mysterious sea monster
00:28known as a pliosaur.
00:33Its remains are very rare,
00:36but some have just been discovered in the cliffs behind me.
00:41This could be one of the largest,
00:44best-preserved pliosaur skulls ever found.
00:47And now, working with scientists,
00:50we can uncover more about this prehistoric giant
00:54than ever before.
00:55What an extraordinary, terrifying thing.
00:59Could this be the greatest Jurassic predator
01:04that ever lived?
01:23Britain has a wealth of fossil sites,
01:28but perhaps none are quite so famous as this,
01:32the Jurassic Coast.
01:41I've been collecting fossils since I was a boy,
01:46and I haven't yet got tired of it.
01:49These days, you're supposed to wear glasses for safety.
01:55And if you wouldn't know a locality,
01:57you'll begin to recognise the sort of block
02:00that might contain the fossil.
02:02And this rock was split earlier
02:05to make it easier to show you.
02:08And if I can hit it quite hard about there...
02:21What about that?
02:24Is anything more beautiful than that?
02:27Fantastic.
02:29Finding even the smallest fossil is a thrill,
02:32but discovering something much larger
02:35can be an unforgettable moment.
02:38And that is exactly what happened
02:40to a fossil enthusiast
02:42who was walking along a beach near Kimmeridge Bay
02:45in southwest England one morning.
02:47I just found something quite extraordinary.
02:50It's the jaw of a massive pliosaur.
02:55It's enormous.
02:57It's a massive pliosaur.
02:59It's the best fossil I've ever found.
03:03It must have just come out of a cliff up there somewhere.
03:07Renowned fossil expert Dr. Steve Etches is called in,
03:11and he knows immediately that it is hugely significant.
03:16Look. Look at those teeth.
03:19Look, it's a tooth there. Look.
03:21Let's have a look at the front.
03:22You can walk along here for hundreds of times.
03:24and not find anything, and then occasionally,
03:27you'll hit the jackpot.
03:29And this certainly is the jackpot.
03:34It's the snout of an enormous pliosaur skull.
03:39And Steve suspects that the rest of the head
03:42might still be embedded in the cliff above.
03:48But he needs to work fast
03:50before the whole thing tumbles into the sea
03:52and is lost forever.
03:55So he quickly gathers a team of experts,
03:58including fellow fossil hunter Chris Moore.
04:03It's day one of the dig.
04:05Steve and team of diggers are up on the cliffs,
04:09and they're putting the net down to stop any loose rock
04:13rolling down and hitting us.
04:15And then we'll go down and expose the skull.
04:20Steve and Chris have worked together for decades,
04:23but this is the biggest challenge they have ever faced.
04:29The skull is nearly 40 feet up from the base of the cliff,
04:34and lying upside down in a horizontal position.
04:41Its full length is not yet known,
04:44but Steve believes it could be over six feet long.
04:55But how did the fossil end up here?
04:59Well, these rocks were once mud on the sea floor,
05:06in which the remains of prehistoric marine creatures were buried.
05:14Over millions of years, the continents shifted,
05:18the seas receded,
05:20and today, as these cliffs erode,
05:23fossilized skeletons are revealed.
05:29The jaw is there,
05:30and the idea is to actually cut this down vertically,
05:33and then we form a platform where the fossil is.
05:41I've known Chris and Steve for many years,
05:44and I can't wait to join them
05:46and find out how they're getting on.
05:53Here we've got a live feed
05:55to them actually digging halfway up the cliff face.
05:58What's happened so far,
05:59the tip of the snout's already come out
06:02and been recovered,
06:03so the rest of it is going into the cliff.
06:06What exactly are they doing there?
06:09At the moment, they're using tinfoil
06:12to try and protect the exposed piece of jaw.
06:15In case something falls on and breaks it.
06:17Yeah, yeah, yep.
06:18And then they're also using a superglue
06:21to consolidate the crumbly teeth
06:24and parts that have been weathered over millennia.
06:27And they're hanging by ropes there?
06:29Yes, pretty much in the centre of the cliff.
06:31Dear me.
06:32Pretty dangerous stuff, this.
06:33Yeah, yeah, it really is.
06:36After you've worked there for a few hours,
06:38it becomes a bit more natural.
06:39Yeah.
06:39And you concentrate on the actual digging.
06:42You must be pretty sure that there's something there
06:45to put this amount of effort into it, really.
06:47Oh, positive there's something there.
06:49It's beautiful.
06:50It's a beautiful specimen.
06:51Is it?
06:52Yeah.
06:54But what can this spectacular find reveal
06:58about the lives of these mysterious sea creatures
07:02and the world they inhabited?
07:08In the late Jurassic, Europe was an archipelago of islands,
07:13much closer to the equator than it is today.
07:17Its seas were warm, shallow, and teeming with life.
07:21And in these waters, underneath my feet, lurked the ultimate marine predator,
07:28the Plyasaur.
07:29The Plyasaur.
07:44Unlike dinosaurs that lived on land, these colossal marine reptiles
07:51spent their whole lives in the ocean.
07:56Thought to have been over 30 feet in length,
08:00similar to a double-decker bus.
08:04They had long, broad flippers, short, strong necks,
08:12huge heads, and enormous jaws.
08:20But there's still a lot we don't know about these great sea monsters,
08:25which is why this new discovery is so important.
08:30Steve believes that the entire Plyasaur may still be inside the cliff,
08:36but it's the skull on which he's concentrating.
08:42A skull can reveal more about an animal than any other part of its skeleton.
08:52Finding a complete specimen is rare,
08:55but it can tell us a great deal about how the animal lived.
09:06It's about hot and thirsty work.
09:09Steve and Chris think they will have about three weeks to dig the fossil out
09:14before the storms of late summer come.
09:20This is a learning curve.
09:22I thought, stupidly, that it wouldn't be quite as hard as this.
09:28We're probably over a metre in.
09:30There's the skull there, just behind me.
09:34It's up to us now to get it out without any damage.
09:39If the skull is successfully extracted,
09:42it will be taken to the Etch's Collection Museum in Kimberage,
09:46which was founded by Steve in 2016,
09:51and now contains nearly 3,000 fossils from the Jurassic period.
09:57This was where the Plyasaur's snout was brought to be assessed.
10:03And I've come here to learn what Steve has found out so far.
10:08What an extraordinary and terrifying thing.
10:13Huge teeth.
10:14They are. They're massive.
10:16These big, fang-like teeth that come up.
10:19And they interlock.
10:20Yes, they do.
10:21So how far do these teeth extend?
10:23They come right up here.
10:25Is that characteristic of this?
10:26Yes, typical Plyasaur.
10:28It's trihedral teeth.
10:29They've got two sharp cutting edges and then a flat face on the inside.
10:35They must have used that to rip apart ichthyosaurs.
10:39Ichthyosaurs, plesiosaurs as well.
10:40We got evidence in the museum,
10:42because they've got sub-triangular teeth.
10:44When they bite in the bone,
10:45they leave a very distinctive tooth hole.
10:48Steve's collection contains a limb bone of a plesiosaur,
10:53another large marine reptile,
10:56which has bite marks on it
10:58that exactly match the size and shape of pliosaur teeth.
11:04What a godsend it is that the teeth are triangular
11:07so that you're able to then identify prey.
11:09Oh, yeah.
11:10Just as much as you can identify the one that was the predator.
11:13That's right.
11:14That's pretty unusual to find teeth in position.
11:16It is.
11:17This is the first pliosaur I've ever seen with actually closed jaws.
11:21It is extraordinary.
11:23Mm.
11:23It is quite extraordinary.
11:25And there is another unusual feature on this snout.
11:30So let me show you the other side.
11:32I'll spin it round.
11:34Oh, gosh.
11:35There's a lot of stuff here.
11:36Oh, yeah.
11:37And these holes here.
11:39Well, I think these are sensory pits.
11:41They're all on the snout.
11:42If you look at them, they go...
11:44See, they strike back in at that angle, you know?
11:46Yes.
11:46They're sensory pits for picking up its prey, I'm pretty sure.
11:49Pretty impressive beast.
11:51Astonishing.
11:51Mm.
11:52But exactly how did these sensory pits help our pliosaur to hunt?
12:03These days, we have equipment that can help us answer such a question.
12:11We take the snout to the University of Southampton,
12:15which has some of the most powerful CT scanners in the UK.
12:21Once the snout has been scanned,
12:25paleobiologist Dr Neil Gostling looks for clues about the sensory abilities of our pliosaur.
12:32So what does this scan tell us?
12:34I've taken the CT data, and we can rack our way through this stack of images,
12:39and we can see all of those internal structures,
12:42which otherwise wouldn't have been revealed to us.
12:45And there are some things which are, I think, quite exciting.
12:49We've got these little structures in red, and I had to do these, each one slice by slice,
12:53dot by dot, because there's lots of imperfections and holes in it.
12:57But these are continuous, and I think these are blood vessels,
13:00little branching blood vessels.
13:02Oh, come on.
13:04You're really telling me this block of stone can show blood vessels?
13:08Yes.
13:08And what I think we've got here are actually branches of the trigeminal nerve,
13:13and these are the sensory nerves in your face that allow you to feel fingers dancing over your cheeks and
13:19what have you.
13:20But if you're in water and you've got these sensory pits, you can detect changes in pressure.
13:26That's going to give you an advantage in what might be murky water where your eyes aren't working so well,
13:31so you can always be sure that you're going to catch your next meal.
13:34It's fantastic.
13:37Knowing how these senses worked, we can start to build up a picture of how our pliosaur hunted.
13:47Its prey, ichthyosaurs, reptiles much the same shape as a modern dolphin and similarly fast and agile.
14:02The sensory pits found on our pliosaur's snout may have acted like miniature pressure pads,
14:10detecting the turbulence produced by ichthyosaurs as they swam through deep water.
14:18In effect, our pliosaur was able to stalk its prey even in the darkest depths just by using its skin.
14:31There are animals today that have similar sensory systems.
14:37Crocodiles have over 9,000 pressure receptors which are concentrated on their snouts,
14:43each one of which is thought to be ten times more sensitive than a human fingertip.
14:57Two weeks into the dig and the work is proving to be even harder than anyone was expecting.
15:08Let me throw this big chunk away.
15:11But at last, there's a breakthrough.
15:16There's something under there which is huge.
15:18Here you've got the jaw showing,
15:21and this one's heading back this way.
15:24It's going to be the underneath of the skull.
15:26There's a vertebra there. There's another vertebra there.
15:30Finding these bones confirms that the entire skull really is inside the cliff.
15:36It's nice to actually see something. You feel like you've been rewarded a bit.
15:41What Alex is doing, he is chipping out a loose tooth.
15:45Hang on, that's the crown.
15:46Yeah.
15:47Oh, that's interesting. Yeah, keep going.
15:50This is part of the root, and there's a pulp cavity there.
15:53That tooth will be probably about ten inches long.
15:58Oh, the thunder's coming. Oh, look at that.
16:00Just as the dig is revealing further exciting finds...
16:04Go on, guys. Yeah, come on.
16:06Because we've got a lot to do. We've got to get you all up.
16:10Conditions become treacherous, and the rope safety team decides that it's too dangerous to continue.
16:18Now it's rained, this lithified mudstone has turned like a slippery clay. It's lethal.
16:27There's certainly no way now, with a stopping now, that we're going to get it done in those days left.
16:35The weather may be against them, but finding a pliosaur tooth is a real stroke of luck.
16:42It could also help us understand more about the type of prey our sea monster could eat.
16:53The teeth of marine predators vary according to their function.
17:01Some are used to shred and slice.
17:07Others, to grasp or crush.
17:12So, what do we know about the teeth of our pliosaur?
17:20Back in Southampton, the investigation of the pliosaur snout has revealed something even more intriguing.
17:29These teeth are extraordinarily well-preserved, aren't they?
17:32Is there new information that we can get from this?
17:35Well, from the CT scan, if we take it back again so we can expose the teeth,
17:40these are large pointed teeth, and these are really well adapted for grasping slippery fish.
17:48But this is on an order of magnitude larger, which would have allowed it to eat all sorts of prey
17:55that are swimming around in the ancient Kimmeridge Bay of the time.
17:59Were the teeth permanent or were they replaced?
18:03As we move it back through, we can see that we've got individual teeth almost all the way along.
18:08However, in one place, we've got this little tooth here, and this is a replacement tooth.
18:14The thing that most animals die of is that their teeth have worn out and they can't feed anymore.
18:20And if you are a large predator and you are catching large prey, you might lose teeth relatively frequently.
18:27Well, this isn't such an issue if you can replace your teeth multiple times throughout your life.
18:33Not only were its teeth replaceable, but they were also shaped differently.
18:39Long and sharp towards the front of its jaws, more hook-like at the back.
18:46This deadly combination meant that the pliosaurs could feed in a variety of ways,
18:52from grabbing large sharks and squid to gripping smaller, slippery fish.
19:11And now the biggest question for Steve and Chris is how to lift the skull off the cliff.
19:17I reckon we'd be taking out a big slab.
19:19One piece?
19:20Yeah.
19:21Cut it underneath?
19:21What, cut underneath?
19:22Yeah.
19:23All the way through?
19:24Yeah.
19:24Well, I can't see any other way of doing it.
19:27If we do it any other way, it's going to just crumble up.
19:30What do you think?
19:30I think I'm going home and not coming back.
19:36Luckily for Steve and Chris, friend and local farmer Rob Vernacom has been devising a solution.
19:46He's building a crate which will be lowered down the cliff, into which the skull will be maneuvered and then
19:53hauled up to the top.
19:55The theory is that whatever angle the skids are, as it comes up the cliff, the box stays level to
20:01protect the fossil,
20:02because we're trying to keep the fossil as level as possible.
20:07The big day finally arrives, and a local army of helpers is assembled for this crucial stage of the operation.
20:17And Steve is feeding the pressure.
20:20With the best way in the world, it looks like it's all going to function, but the risk is immense.
20:24You know, what happens if it just actually turned on its side?
20:27There's a lot of things that could go wrong, so it's a risky sort of time.
20:33This is one of the largest and best-preserved Pliosaur skulls ever found, so the stakes are very high indeed.
20:50When it comes down, we've got to get that aligned and we've got to get that jaw, that skull, inside
20:55that box.
20:56And we've got to be really careful that that sled has got a metal bar, and as it comes down,
21:02it doesn't hit the nose.
21:06No one's ever done this before, ever.
21:08Extracting a giant skull halfway down a cliff face.
21:13The crate must be lowered into position with great precision if the skull is not to be damaged.
21:20The position it's coming down in, it's almost going to glance the side of the skull.
21:26Move it! Stop! Stop!
21:30So somehow we've got to manually try and move the whole sled over.
21:35I think we can afford to do 30 centimetres lower and no more.
21:42After weeks of back-breaking work, emotions are running high.
21:47Down! Quick! Quicker!
21:51This moment's really fraught.
21:55We've got one skid just about glancing the side of the skull,
21:59and we've got to try and pull it out now to get it over the edge.
22:03Very slowly, six inches.
22:06One clumsy move, and the skull could be smashed.
22:15Oh, my!
22:17Pull! Pull again!
22:18That's all right, that's all right.
22:19Missed it.
22:20We've done it.
22:20Stop! Stop!
22:22It's all pretty stressful.
22:24Every part of this is really, really stressful.
22:27After quite a few hours, we've got it into position.
22:31We haven't knocked the end of the snout off so far,
22:34and it's all ready to go.
22:38But the next stage looks even more risky.
22:41Just retreat from the edge, and we're going up the ropes now.
22:46Al and Steve are going to go up to the hole
22:50and attach the winch,
22:52and then start the process of slowly dragging it into the box.
22:58Shifting a fossil that weighs over half a tonne
23:02is really dangerous.
23:06Moving.
23:07It's very nervous, and it's very tense,
23:09so let's see how it goes.
23:17Oh, go on.
23:18Good.
23:19Good.
23:20Yeah, that's better.
23:22That's...
23:22Whoa!
23:23Right.
23:24I think slide it straight in.
23:26Steve.
23:27Is it okay?
23:28Has it come off okay?
23:30Well, we're losing a bit of it,
23:32but you can't oz it, mate.
23:33Go on.
23:35Go on.
23:37Right, that's on it.
23:38There you go.
23:38Right, keep going.
23:40Good, Sandy.
23:42That's well in.
23:43It's right in the cage now.
23:45Hey, the fossil's in.
23:47Brilliant, brilliant.
23:48We're all cheering here.
23:49Well done, well done.
23:50Well done, everybody.
23:52Right, well done.
23:53Brilliant.
23:55We've overcome a lot of problems to get this far,
23:57and we've done it by the skin of our teeth.
24:01The skull, at last, is in the crate.
24:04Take up the sack again.
24:06Right.
24:09But shifting it carelessly, let alone dropping it,
24:12could be disastrous.
24:15Come over a bit.
24:17There'll be six ropes coming up to be able to lift it
24:20and hold it steady.
24:22Hopefully.
24:23With the toy coming in and the sun setting,
24:26we couldn't cut at any point.
24:31Okay, right.
24:33Whoa, whoa, whoa, whoa.
24:37Finally, the skull is safe.
24:40Brilliant, Rob.
24:41Well done.
24:42Well done.
24:44Yeah.
24:48It's amazing.
24:50It's a dream come true.
24:52And I'll tell you what.
24:53I don't think anyone in their right would ever believe
24:55we could have done it.
24:57Three weeks ago, it was buried in a cliff face.
25:00Found the top food chain predator,
25:02and now we're bringing it back to life.
25:04And this would be one of the best that's ever been found.
25:06Hey!
25:07Hey!
25:08Good on you.
25:09Oh, no, none of that.
25:11Hey!
25:12Get off you, no devils.
25:14Come on.
25:14Oh dear, oh dear.
25:17He's out.
25:18The next day starts.
25:29The skull is transported to Steve's workshop.
25:34Ready?
25:35Go.
25:38Right up.
25:40Oh my God.
25:41The mud stone's cracked and dried.
25:44Of course, what it's done is just cracked the bone as well.
25:47Jeepers creepers.
25:48You'll be fine.
25:49Oh yeah.
25:53The painstaking task of removing the stone from around the skull,
25:57so that it can be examined in detail,
26:01can at last begin.
26:04After the heavy work of the dig,
26:07this stage requires a delicate touch.
26:11First, Steve removes the rock surrounding the fossil,
26:15so that the fragile areas of the skull can be strengthened.
26:21Then, using an air abrasion tool,
26:24he starts work to reveal the more intricate details
26:28about the anatomy of this extraordinary animal.
26:32This giant sea monster,
26:34after 150 million years,
26:38finally begins to emerge from the rock.
26:44And I have the privilege of coming to see this whole skull
26:48for the first time.
26:51So, here it is.
26:54And it's enormous.
26:57I am meeting Dr. Judith Sassoon,
27:01the paleontologist who has studied pliosaur specimens for decades.
27:07Does it still take your breath away as it takes mine?
27:10It is a most astonishing specimen, David.
27:13I'm very pleased to be part of the work on it.
27:19What insights can Judith give us
27:22into the life of this ancient monster?
27:28How is it coming along?
27:29What sort of detail it can get from this which you never knew before?
27:33Steve Etches has been working on it now for several months,
27:37and has made some fabulous progress.
27:40We're seeing, as it's being prepared,
27:43gradually more and more detail being revealed.
27:46So far, we have some information about its senses.
27:52Really?
27:53Was that outside good?
27:54There are indications that, in fact, it could have been.
27:59The eyes themselves were quite important for this animal.
28:05One of the reasons is the position itself.
28:08The eyes are on the side of the head,
28:12more or less in the middle,
28:14so not too high and not too low.
28:20This important feature of the skull
28:22may suggest how our pliosaur hunted in the open ocean.
28:30The position of the eyes in living animals varies
28:34according to the way in which they hunt.
28:39Dolphins are pursuit hunters.
28:42Their eyes are placed on the side of their heads,
28:46giving them panoramic vision,
28:51helping them to attack their prey more accurately.
28:58Ambush predators, such as crocodiles,
29:00have eyes higher up on their heads.
29:06So they can remain just below the surface,
29:09with only their eyes above water,
29:12and judge when to attack.
29:19Our pliosaur seems to have had something in between.
29:24With an eye position that not only enabled it
29:27to pursue prey through the water with accuracy,
29:31but, alternatively, surprise it by attacking from below.
29:38And there is another remarkable feature
29:41which could tell us more about where our sea monster may have hunted.
29:46We talked about eyes.
29:48There's also another interesting structure,
29:51which is the parietal eye.
29:54In many reptiles, this still exists.
29:58When it is present in terrestrial animals,
30:01it has a full eye structure like the lateral eyes,
30:05and is light sensitive.
30:10The parietal eye on the top of the head is something of a puzzle.
30:16It's known as a third eye, and is still found in a few living species.
30:22It apparently helps an animal to regulate its body clock.
30:31The pliosaur's parietal eye is thought to have had a lens,
30:36a cornea, and a retina.
30:39Although its exact function is unclear,
30:42it may have enabled our sea monster to gauge which way was up
30:47when swimming at depth,
30:49and potentially navigate deeper hunting grounds.
30:55What other questions would you wish to the skull to provide answers for?
31:00I've already made some measurements on this animal,
31:03and the proportions do seem to be different from other pliosaurs that we know.
31:08The skull is quite long-snouted,
31:13but the position of the nose and the eye and also of the crest
31:20suggests that it is something else, something new.
31:24A new species of pliosaur?
31:26Of pliosaur, yes.
31:27A new species? Really?
31:29I think it could be, yes.
31:33The revelation that our pliosaur could be a new species
31:37is truly exciting.
31:45There are only eight recognized species of pliosaur,
31:51and this skull is certain to provide new scientific data
31:57on the evolution of these mysterious marine reptiles.
32:02I have to say, you take my breath away.
32:06The detail which you can deduce, it is mind-blowing, I think,
32:11and that's what paleontology is about.
32:13I used to think it was just a question of finding a fossil
32:16and digging it out and saying how nice it was.
32:19You made it sound rather different.
32:26In recent decades, huge advances have been made in our ability to study prehistoric animals.
32:34And we can now investigate the predator power of our pliosaur in more detail than ever before.
32:46Paleobiologist Dr. Andre Rowe is a world-leading expert in 3D visualization of fossils.
32:54First thoughts, this thing is absolutely massive, and I will also add that the level of preservation is amazing.
33:01This is actually a one in a million, maybe one in a billion type specimen here.
33:07Using the latest technology, Andre is carrying out the world's first surface scan of a pliosaur skull.
33:19So right now we're capturing basically hundreds of thousands of images all at once.
33:24The end result is a really nice looking 3D model.
33:27I think we'll be able to unlock a lot of mysteries about what these sea monsters were doing.
33:31And I'm really excited to see where it takes us.
33:37Once the scan has been finalized, I meet Andre at the University of Bristol to discuss his findings.
33:47Has he seen anything in the skull structure that shows our sea monster had the power of a truly deadly
33:54predator?
33:56There's some massive openings back here along the jawline, and that's good for mussels to attach and bulge out.
34:02There'd be a mussel goat running through there.
34:06Yes, we have the pterygoid mussel group, which is in a lot of big dinosaurs, and it's integral to having
34:12a really strong bite.
34:14And we've hypothesized that this particular pliosaur is kind of the apex predator in the Jurassic ecosystems it was living
34:20in.
34:21Now this, of course, is not a dinosaur, but neither is it a modern reptile, but it does look a
34:26lot like a crocodile, doesn't it?
34:28Yes, well, we have this process called convergent evolution, where a lot of animals will adapt this similar-shaped skull
34:35or similar trends throughout their evolutionary history, even if they're not closely related.
34:39That's because having those similarities can give you a lot of advantages.
34:42But in terms of this pliosaur, it's got that kind of streamlined skull that's kind of broad in the back.
34:49It's very triangular-shaped.
34:50I think that it's good for swimming quickly and ambushing prey.
34:54Does this skull give you any information about what animals' prey might have been?
34:58The animal would have been so massive that I think it would have been able to prey effectively on anything
35:03that was unfortunate enough to be in its space.
35:06A popular hypothesis is that these animals are actually ripping off the limbs of other animals to disable them from
35:12swimming away, and then kind of going in for a kill.
35:14So this is really a top predator?
35:17Yes. I have very little doubt just judging from how massive that skull is. I don't see what could have
35:23possibly hurt it.
35:24What size is that, actually?
35:26So the actual skull itself comes in at about six and a half feet, about six foot six.
35:31So it's longer than I am tall?
35:33Yes. It's quite a big boy, and that's just the skull.
35:37The dimensions of a fossilized skull enable us to estimate the overall size of an animal when it was alive.
35:45And based on Andre's measurements, our pliosaur could have been up to an astounding 40 feet long.
35:55Just from the sheer size of it, just from looking at this animal and how big those pterygoid muscles would
36:00have been at the back of the jaw, the animal would have delivered a devastating bite, no doubt.
36:06A powerful bite is vital to the success of any marine predator.
36:14Scientists are able to estimate how much force an animal can exert when biting into its prey.
36:21And great white sharks have one of the strongest bites, at around 10,000 newtons.
36:34But how do you work out the bite force of a creature that became extinct millions of years ago?
36:41Professor Emily Rayfield is a world-renowned paleontologist who specializes in skeletal mechanics.
36:50Using the model created by Andre, Emily has assessed the bite force of our pliosaur.
36:57So this is a 3D print, a model. It's not full size, though it's just over a third of the
37:03size of the actual animal.
37:04These large openings are the spaces in the skull which would have been filled with jaw-closing muscles.
37:10So you can estimate the force of the bite from the size of those muscles?
37:16Exactly, yeah. We can get an estimate of that from here.
37:20We know that muscles of a certain size, a certain area, are capable of generating a certain amount of force.
37:29Saltwater crocodiles have got the largest ever bite force measured, and they're up to about 16,000 newtons.
37:38And these?
37:39So our pliosaur here, from the estimations that we've made, has a bite force that's about twice the size of
37:45that of the largest saltwater crocodile that's ever been measured.
37:48And it's in the region of around 32,000 newtons.
37:51So this is the most powerful biter in the sea that there has been, or that we know of?
37:59That we know of, absolutely, yes, definitely. If you're looking at kind of statistics in terms of car-biting metrics,
38:05I'm pretty sure it could probably bite through a car.
38:08So it's a monster?
38:09Absolutely.
38:19The evidence gathered from the skull so far suggests that this pliosaur had the jaws, teeth and senses of a
38:29highly successful hunter.
38:34It's long snout, short neck, and streamlined skull enabled it to move easily through the water.
38:43But what else helped our enormous sea monster to power through the Jurassic Seas fast enough to catch its prey?
38:52Pliosaurs were unique in the natural world, as they had four almost identical wing-like flippers.
39:01How pliosaurs used their flippers has been debated by paleontologists for decades.
39:08Some believed that they moved using a sort of rowing stroke, like oars in a boat, while others argued they
39:17used a flight stroke,
39:19seen in animals such as sea turtles.
39:23But in recent years, scientists have been able to use computer modelling to finally solve this mystery.
39:30And it appears that these giant sea monsters swam in a way that is surprisingly similar to a very different
39:39type of animal,
39:41one that is alive today.
39:51Penguins may appear somewhat clumsy as they waddle around on land.
39:57But once they're in the water, they move very differently.
40:01These are humboat penguins, and they're excellent swimmers.
40:08Their streamlined body shape and their oily feathers enable them to reach astonishing speeds of up to 30 miles an
40:16hour.
40:16But a key factor behind penguins' speed are their flippers, which, underwater, act like propellers, driving them forward and increasing
40:26their speed dramatically.
40:30In slow motion, you can see that the penguins are using a lift-based underwater flight movement,
40:38twisting their wings as they flap and propelling themselves forward on the upstroke as well as the downstroke.
40:47As strange as it may seem, it's thought that pliosaurs would have moved in a very similar way.
40:55But, of course, pliosaurs were enormous, and most large animals are relatively slow moving.
41:03So, as an apex predator, how could this huge creature maneuver itself fast enough to catch its prey?
41:12To find out, I've come to the Hydrodynamic Laboratory at Imperial College London,
41:19where Dr. Luke Muscutt is studying the locomotion of pliosaurs using a rather unusual research tool.
41:27How did you first become interested in the way that pliosaurs swam?
41:32It's the only animal that we know of that has four large flippers.
41:38So, the question is, how did they use them?
41:40The fossils of the pliosaurs show that the flippers were very much like wings.
41:47So, what I found was that the hind flipper can actually operate at a much higher thrust and at a
41:53much higher efficiency
41:54because it's utilizing the wake of the flipper in front of it.
41:59We can see a similar effect in the flight of migrating birds such as geese.
42:07When geese are flying in formation, each bird benefits from the uplift created by the one in front of it,
42:16so that they fly in a very energy-efficient way.
42:22So, you can think of the pliosaur as almost two birds, one flying behind the other,
42:27and the back one is benefiting from the one in front.
42:30That's an extraordinary parallel, yes.
42:32The hind flipper has increases in thrust and efficiency of up to 40%.
42:38So, this would have increased the swimming speed that pliosaurs would have been able to achieve
42:44and increased the number of different things it could eat.
42:48To take his research to the next level, Luke has built a robot
42:53to study the swimming pattern of pliosaurs more accurately than ever before.
42:58So, what more information do you think you can get from this model?
43:03This robot enables me to test the complete animal.
43:07How fast something can move is an absolutely critical part of what that animal is.
43:14And it tells us what animals it could have eaten, how far it might have been able to travel.
43:21All sorts of questions come back down to its locomotion ability.
43:27Have you estimated the speed that this might produce?
43:30Well, I've only finished building this yesterday.
43:33Oh, really?
43:33So, so far I haven't actually run the experiments yet.
43:36If you'd like to have a go, you're more than welcome to...
43:38Yes. Oh, show me.
43:39So, if you just move this joystick sort of upwards further.
43:44So, this is how the pliosaur would have swam.
43:47The flippers move primarily up and down.
43:50It's much more like a bird flies.
43:55Luke and his team set up the robot for a test swim.
43:59And they interest me with its maiden voyage.
44:03If you'd like to take the control.
44:08There we are. It's off.
44:10I suppose, actually, that's only a model.
44:12But if it was full-sized, it would be going quite fast.
44:15Indeed.
44:15You can just imagine it chasing after a smaller Igtheosaur.
44:21Luke's research is so new it's yet to be published.
44:25But it's helping to provide a new perspective
44:28on these extraordinary animals.
44:36Large marine predators like minke whales and orcas
44:40can swim at great speed through the ocean.
44:45What speed might our pliosaur with its four flippers?
44:50have been capable of.
44:53Estimates suggest that they could have accelerated up to 30 miles an hour,
44:59making them one of the fastest animals in the Jurassic Seas.
45:12This skull is not only helping us to understand more about the lives of these giant sea monsters,
45:18but also allows scientists like Dr. Andre Rowe to visualize the Jurassic World as never before.
45:28So often, I've been involved in looking at fossil skeletons and the skull.
45:33Unless the skull is there, you're really missing an awful lot of information.
45:38We are lucky to find this as the first thing.
45:40Yes.
45:41I am very biased since I study feeding and teeth,
45:44but I think the majority of the information about an animal you can get from its skull.
45:47The brain, the teeth, what it was feeding on,
45:50its maximum body size if you have the whole skull.
45:53It's just a treasure trove of information.
45:55And we're very fortunate to have the whole thing.
45:57One of the reasons why I love the UK is because it's got such a great collection of marine reptiles.
46:04Delighted to hear it.
46:05I mean, in America, we've got our big Tyrannosaurus and our Triceratops,
46:08but the UK is great for marine reptiles.
46:10Well, we did discover the dinosaurs.
46:12Yes, the science of paleontology did originate here.
46:15How would it compare with T-Rex?
46:17I imagine it would be pretty comparable.
46:19And they were kind of both the respective apex predators and their ecosystems.
46:23So, I have no doubt that this was sort of like an underwater T-Rex, if you will.
46:28Okay, let me ask you the million-dollar question.
46:32In a battle between T-Rex and our Pliosaur, who's going to win?
46:39As much as it pains me and brings a tear to my eye to admit it,
46:42I think my T-Rex is going to lose this fight.
46:45And then millions of years later, an American paleontologist will envision the scene and break down into tears.
46:54Bringing an enormous predator back to life after 150 million years is no easy task.
47:03But restoring this giant skull is a labor of love for Steve and his team.
47:11Almost a year after the skull was discovered, I returned to Kimmeridge to see how they're getting on.
47:19My goodness.
47:23It is absolutely magnificent.
47:26It's astonishing.
47:27It's bigger than a T-Rex.
47:30Is it?
47:31Yeah, yeah.
47:31About the skull?
47:32Yeah.
47:33Bigger than any T-Rex ever found.
47:35David, now what we've done, since you've come here last,
47:39is I've air-penned off all the mudstone and then air-braided it.
47:44Now, the air-braiser machine cleans out all these little voids
47:47and you see every little detail, every suture where the bones join together,
47:51you can see every detail.
47:52That's what we really wanted.
47:54So the teeth here have been basically tumbled on the beach
47:58and the shingle had worn away all the crowns.
48:01So we're going to do a bit of dentistry on them.
48:04So we've got this tooth which has been scanned
48:07and then we're going to increase or decrease it
48:09and then add all the teeth back in position,
48:14show people what it actually looked like.
48:16You must feel looking at this.
48:18I mean, I know it was a huge amount of work to get it out.
48:21We never thought we'd get it, to be honest. I'll be honest with you.
48:25Well, it's certainly a triumph.
48:29Yeah, quite an emotional moment for everyone.
48:31I'm sure.
48:32A sensation.
48:40Once the pliosaur's dagger-like teeth are added,
48:44the picture is finally complete.
48:52Our journey of discovery has shown that this sea monster
48:57was one of the greatest predators the world has ever seen.
49:03And we can now visualize more accurately than ever
49:07how it may have hunted in the Jurassic Seas.
49:20Icthyosaurs, swimming in groups along the coast.
49:27Concentrating on hunting their prey.
49:31Unaware that they themselves are being stalked.
49:38On their trail,
49:41our pliosaur uses its highly-tuned senses
49:45to launch an attack.
49:54In the chase, its four flippers,
49:56each measuring over six feet long,
49:59drive it through the water at great speed.
50:06Splitting the shoal,
50:08it isolates its target.
50:13Our sea monster's primary weapons
50:15are its 90 razor-sharp teeth,
50:20with which it slices through its victim's flesh.
50:27The impact alone may have been enough to kill.
50:33But with a bite force twice the strength of any animal living today,
50:40its prey had little chance of survival.
51:02From a chance discovery on a beach one morning,
51:06to the painstaking restoration of such a rare and impressive specimen,
51:11the story of this fossil is one of skill, dedication,
51:17and of fascinating scientific discoveries made along the way.
51:21We've been given a unique insight into the life of our pliosaur
51:26that swam in the Jurassic Seas 150 million years ago.
51:31But we're also reminded
51:33that there is still so much to learn
51:36about these extraordinary prehistoric animals.
51:42And I, for one, will never tire of discovering more.
51:49I'm not a man ...
52:04who was watching the world.
52:04No man.
52:05Do you know a man being?
52:06The earth is incredibly cheap.
52:07No man is a man being too broke.
52:08If you're capable of knowing a man being too broke,
52:09I'm afraid of knowing that you're alive.
52:09Do you know the truth?
52:17I'm afraid of knowing it.
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