Planet Dinosaur

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0:00:06 > 0:00:11This is one of the most awesome dinosaurs ever discovered.

0:00:11 > 0:00:13Meet Spinosaurus,

0:00:13 > 0:00:18a truly amazing predator that lived 95 million years ago.

0:00:22 > 0:00:26In the dinosaur world, this is the Terminator,

0:00:26 > 0:00:32at a stunning 17 metres in length and 12 tonnes in weight.

0:00:34 > 0:00:36Spinosaurus is one of the largest predators

0:00:36 > 0:00:39to have ever walked the planet.

0:00:40 > 0:00:42It lived in North Africa.

0:00:43 > 0:00:46Here, it's roaming a swamp,

0:00:46 > 0:00:49but this hunter's favourite prey lived elsewhere.

0:00:53 > 0:00:54HISS

0:00:54 > 0:00:58Spinosaurus's meal of choice was fish, not meat.

0:01:03 > 0:01:07This is a dinosaur that loved to hunt in water.

0:01:07 > 0:01:12Standing in the river shallows, Spinosaurus plays a waiting game.

0:01:14 > 0:01:16It's on the lookout for one of these.

0:01:16 > 0:01:22Onchopristis, a giant eight-metre long swordfish.

0:01:22 > 0:01:26There's enough fresh sushi there for a whole Japanese restaurant.

0:01:30 > 0:01:34You can find this kind of hunting going on in the wild today.

0:01:34 > 0:01:37This grizzly bear loves a bit of raw fish too.

0:01:38 > 0:01:41He and his mates know that thousands of juicy salmon are swimming

0:01:41 > 0:01:45up river, and they're waiting for a meal to come their way.

0:01:47 > 0:01:53And their super-quick reactions mean they can catch this fish in mid-air.

0:01:55 > 0:01:58But how do we know that Spinosaurus was as partial to fish

0:01:58 > 0:02:00as that grizzly bear?

0:02:01 > 0:02:03By looking at the evidence, that's how.

0:02:05 > 0:02:09These are the tooth sockets in a Spinosaurus's jaw.

0:02:09 > 0:02:12It was found in 2005 in North Africa.

0:02:12 > 0:02:15Stuck in one of the sockets is a tiny piece of backbone

0:02:15 > 0:02:18from another creature.

0:02:19 > 0:02:23This spino clearly didn't brush his teeth before he went to bed!

0:02:23 > 0:02:29That bone fragment was from a swordfish, possibly Onchopristis.

0:02:29 > 0:02:33These juicy fish were one of Spinosaurus's favourite foods.

0:02:33 > 0:02:36And, a bit like a bored angler,

0:02:36 > 0:02:40Spino would spend hours waiting for these tasty river treats to swim by.

0:02:42 > 0:02:46Here was a beast that loved poking its snout into a fast-flowing river.

0:02:48 > 0:02:51And Spinosaurus's way of catching fish is really clever.

0:02:51 > 0:02:54Its secret lies in that snout.

0:02:54 > 0:02:58It has lots of small holes in it that are very similar

0:02:58 > 0:03:00to those of a crocodile.

0:03:05 > 0:03:09In a crocodile, these snout holes contain special sensors.

0:03:09 > 0:03:12These help the croc to feel small changes of pressure

0:03:12 > 0:03:16caused by other creatures disturbing the water nearby.

0:03:16 > 0:03:21That signal is one of the ways it zeroes in on prey.

0:03:25 > 0:03:29And dinosaur experts believe that the Spinosaurus had sensors

0:03:29 > 0:03:33like the crocodile, an amazing ability that meant

0:03:33 > 0:03:35it could strike at these onchopristis

0:03:35 > 0:03:38without even seeing them.

0:03:56 > 0:04:00Take a look at this amazing creature.

0:04:00 > 0:04:04A flying monster, its name is Hatzegopteryx.

0:04:04 > 0:04:09This is a kind of prehistoric flying reptile called a pterosaur

0:04:09 > 0:04:14and it's one of the largest flying creatures ever known.

0:04:16 > 0:04:18This mind-blowingly massive beast

0:04:18 > 0:04:22patrolled the skies 65 million years ago.

0:04:23 > 0:04:27At that time, Europe was made up of lots of islands, one of which

0:04:27 > 0:04:32was called Hatzeg, which is how this monster gets its name.

0:04:32 > 0:04:34And it really is a monster.

0:04:36 > 0:04:40Hatzegopteryx was over five metres tall

0:04:40 > 0:04:43and had an enormous ten metre wide wingspan.

0:04:46 > 0:04:51That's as big as this modern jet fighter.

0:04:51 > 0:04:55Hatzegopteryx was an incredible flying machine.

0:04:55 > 0:04:57But it preferred to hunt on the ground.

0:05:02 > 0:05:08It could gobble up these much smaller herbivores with ease.

0:05:08 > 0:05:13Usually, long-necked sauropods, like these magyarosaurs,

0:05:13 > 0:05:17were the biggest beasts in the dinosaur world.

0:05:17 > 0:05:20Here, though, they're dwarfed by Hatzegopteryx.

0:05:23 > 0:05:28How do we know that a flying reptile could actually get this big?

0:05:28 > 0:05:31By taking a look at the evidence, that's how.

0:05:36 > 0:05:39These are the fossilised footprints of a pterosaur,

0:05:39 > 0:05:41very like Hatzegopteryx.

0:05:42 > 0:05:48Discovered in 2002, they measure a massive 35 centimetres across,

0:05:48 > 0:05:52proving that these creatures could be huge.

0:05:53 > 0:05:57Imagine, if the hatzegopteryx were around today,

0:05:57 > 0:06:01it would be three times bigger than the world's largest flying bird,

0:06:01 > 0:06:04the wandering albatross.

0:06:04 > 0:06:09And when it landed on the ground, it would be as tall as a giraffe.

0:06:15 > 0:06:18Take a look at this condor from South America.

0:06:18 > 0:06:21This bird glides a bit like Hatze.

0:06:21 > 0:06:25A condor's wings take advantage of warm air currents called thermals.

0:06:25 > 0:06:29They help it stay in the air for hours on end.

0:06:29 > 0:06:32Dinosaur experts believe pterosaurs like Hatzegopteryx

0:06:32 > 0:06:34could do the same.

0:06:54 > 0:06:58If you thought Tyrannosaurus rex was an impressive dinosaur,

0:06:58 > 0:07:02take a look at this prehistoric predator.

0:07:06 > 0:07:08This is Carcharodontosaurus.

0:07:08 > 0:07:10ROAR

0:07:10 > 0:07:14Its name means "shark-toothed lizard".

0:07:14 > 0:07:17This monster grew up to 13 metres long.

0:07:19 > 0:07:22An adult weighed a hefty seven tonnes.

0:07:22 > 0:07:28It ruled the roost in North Africa 95 million years ago.

0:07:28 > 0:07:30ROAR

0:07:30 > 0:07:32Carcharodontosaurus was a carnivore,

0:07:32 > 0:07:35and a whole ton heavier than T-Rex.

0:07:37 > 0:07:42How much meat do you think a killer of this size ate each day?

0:07:43 > 0:07:48The amazing answer is that a full-grown carcharodontosaurus

0:07:48 > 0:07:53needed to eat a whopping 60 kilograms of meat every day

0:07:53 > 0:07:55just to survive.

0:07:55 > 0:07:59That's like having 480 hamburgers every day.

0:08:00 > 0:08:03Now, the carcharodontosaurus liked to hunt

0:08:03 > 0:08:06by creeping up slowly on its prey.

0:08:07 > 0:08:10But amazingly, for such a large beast,

0:08:10 > 0:08:13we've recently discovered that it could really move it too.

0:08:15 > 0:08:16Watch this.

0:08:21 > 0:08:25Over short distances, this hunter's explosively powerful legs

0:08:25 > 0:08:28could get it running up to 20 miles an hour.

0:08:28 > 0:08:32That meant it could catch lighter prey like this ouranosaurus.

0:08:37 > 0:08:41So, where would you have found one of these ruthless killers?

0:08:41 > 0:08:47Most of the 95 million-year-old carcharodontosaurus bones

0:08:47 > 0:08:51have been found in various sites across North Africa.

0:08:53 > 0:08:59Life for these big killers was a constant battle. For food...

0:08:59 > 0:09:01For territory...

0:09:01 > 0:09:04For dominance over other carcharodontosaurs.

0:09:11 > 0:09:12ROAR

0:09:12 > 0:09:16But how can we tell this kind of head-to-head battle went on?

0:09:18 > 0:09:21By closely looking at the evidence, that's how.

0:09:23 > 0:09:25This is a recently discovered lower jaw bone.

0:09:27 > 0:09:29It came from a meat-eating dinosaur.

0:09:29 > 0:09:35It's big, nearly half a metre long, and the exciting bit?

0:09:35 > 0:09:36Two bite marks.

0:09:37 > 0:09:41The size and shape of the tooth marks show that another dinosaur

0:09:41 > 0:09:44of the same species had sunk its teeth into this jaw.

0:09:47 > 0:09:50For a carcharodontosaur to dominate its patch,

0:09:50 > 0:09:54it first had to see off rival carcharodontosaurs.

0:09:58 > 0:10:02And that's often the way it still goes in the wild.

0:10:02 > 0:10:05This frilled lizard from Australia has found a good feeding area

0:10:05 > 0:10:08with lots of tasty insects.

0:10:09 > 0:10:13So when another male lizard of the same size enters its patch,

0:10:13 > 0:10:15battle commences.

0:10:15 > 0:10:16HISSING

0:10:19 > 0:10:21And goes on for a long time.

0:10:24 > 0:10:25ROAR!

0:10:27 > 0:10:31But when two seven-tonne carcharodontosaurs went at it,

0:10:31 > 0:10:34I wonder what kind of destruction that would cause.

0:10:40 > 0:10:44Well, with the help of some power tools and a chunk of steel,

0:10:44 > 0:10:46I'm about to find out.

0:10:46 > 0:10:48It's hard to imagine the damage

0:10:48 > 0:10:51these carcharodontosauruses would've caused

0:10:51 > 0:10:53if they start throwing their weight around.

0:10:53 > 0:10:57But to get an idea, we've built a carcharodontosaurus foot.

0:10:57 > 0:11:03It's been very specifically shaped to match the fossilised footprints

0:11:03 > 0:11:06that have been found from the real thing.

0:11:06 > 0:11:09It's made of steel, not flesh and bone,

0:11:09 > 0:11:12but hopefully it's going to be strong enough for the task ahead.

0:11:12 > 0:11:16You see, I want to attach this to something that can provide

0:11:16 > 0:11:19the power and weight that would've been there

0:11:19 > 0:11:21with a real carcharodontosaurus.

0:11:21 > 0:11:23Rich!

0:11:23 > 0:11:25'And this big digger is it.

0:11:27 > 0:11:28'A huge hydraulic excavator.

0:11:28 > 0:11:33'35 tonnes of steel on caterpillar tracks.'

0:11:33 > 0:11:37Rich the driver assures me that this enormous excavator

0:11:37 > 0:11:40can get my carcharodontosaurus foot to step down

0:11:40 > 0:11:42with the seven tonnes of force

0:11:42 > 0:11:46that the real thing would have applied with every stride.

0:11:46 > 0:11:49Want to grab the back end? This is heavy, to say the least.

0:11:49 > 0:11:52Ah! Cheers.

0:11:52 > 0:11:59Thing is, first job is to attach it to this digger.

0:12:08 > 0:12:10That's attached.

0:12:10 > 0:12:14Now, let's see what kind of impact a dinosaur like this would have had.

0:12:15 > 0:12:19I need something else made of steel

0:12:19 > 0:12:22for my carcharodontosaurus foot to tread on.

0:12:23 > 0:12:25So, I've got myself a scrap car.

0:12:25 > 0:12:29Now, obviously, they didn't have those 95 million years ago,

0:12:29 > 0:12:33but it's here to represent the unfortunate dinosaurs

0:12:33 > 0:12:37that may have got in the path of the mighty carcharodontosaurus.

0:12:37 > 0:12:42Right, Rich, can you give this a big, seven-tonne stamp?

0:12:51 > 0:12:52Erm...

0:12:52 > 0:12:54It didn't really stand a chance.

0:12:54 > 0:12:57And I think that's probably what a lot of dinosaurs

0:12:57 > 0:13:00that hung around North Africa 95 million years ago felt.

0:13:00 > 0:13:03Because weight is a massive advantage

0:13:03 > 0:13:05in the battle for dominance.

0:13:05 > 0:13:08And the carcharodontosaurus carried a lot of weight.

0:13:10 > 0:13:12And this one's angry.

0:13:12 > 0:13:17'I'm not sure that that's the kind of thing covered by car insurance.'

0:13:34 > 0:13:36Meet Nothronychus.

0:13:36 > 0:13:40A strange-looking dinosaur with a potbelly.

0:13:41 > 0:13:45It lived in swampy jungles like this 92 million years ago.

0:13:51 > 0:13:53Because it walked upright on two legs,

0:13:53 > 0:13:58Nothronychus has the classic look of a meat-eating dinosaur.

0:13:58 > 0:14:01But it's actually a vegetarian.

0:14:01 > 0:14:06It's one of a weird group of dinosaurs called theriznosaurs.

0:14:06 > 0:14:09Twice as tall as an adult human, it had a lengthy neck

0:14:09 > 0:14:11and powerful legs.

0:14:14 > 0:14:19It used its very long, curved claws to pull down branches,

0:14:19 > 0:14:21to get nice, juicy leaves to eat.

0:14:21 > 0:14:23In fact, its name means "sloth-like claws".

0:14:30 > 0:14:31And here's why.

0:14:31 > 0:14:35Northro's claws are very like those of this bizarre-looking creature -

0:14:35 > 0:14:37the sloth.

0:14:38 > 0:14:41This gentle, tree-dwelling mammal lives in South America.

0:14:41 > 0:14:43It uses its claws to grab

0:14:43 > 0:14:48and eat leaves in a very similar way to how we think Nothronychus did.

0:14:48 > 0:14:53Unlike sloths, though, Nothronychus had to be ready to defend itself

0:14:53 > 0:14:55against some dangerous predators.

0:15:01 > 0:15:04In these same swamps is an eight-metre-long tyrannosaur.

0:15:04 > 0:15:08A fearsome carnivore from the same family of dinosaurs

0:15:08 > 0:15:10as the famous T-rex.

0:15:11 > 0:15:15And this tyrannosaur fancies some nothronychus for dinner.

0:15:17 > 0:15:19And it's at times like this

0:15:19 > 0:15:23that those claws become weapons of self-defence,

0:15:23 > 0:15:28making these potbellied beasts a match for the mighty tyrannosaurs.

0:15:28 > 0:15:31Nothronychus is just as powerful

0:15:31 > 0:15:33and aggressive as these killers.

0:15:33 > 0:15:37And that's because they're actually close relatives.

0:15:42 > 0:15:48So, if they look like a carnivore and they fight like a carnivore,

0:15:48 > 0:15:51how can we be sure that they were actually herbivores?

0:15:51 > 0:15:54By taking a look at the evidence, that's how.

0:15:57 > 0:16:01In 2001, the bones of a dinosaur very like Nothronychus

0:16:01 > 0:16:04were discovered in the USA.

0:16:04 > 0:16:07Amongst them were fossil teeth.

0:16:07 > 0:16:10Their shape showed they were designed for eating leaves,

0:16:10 > 0:16:12not meat.

0:16:13 > 0:16:16Nothronychus, just like these tyrannosaurs,

0:16:16 > 0:16:19started off as a meat-eating dinosaur.

0:16:19 > 0:16:22But over hundreds of thousands of years,

0:16:22 > 0:16:25Nothronychus changed its eating habits.

0:16:25 > 0:16:29It still looked like a carnivore, with its upright stance,

0:16:29 > 0:16:30but now it lived off plants.

0:16:35 > 0:16:39'Let's find out more about the Nothronychus diet

0:16:39 > 0:16:40'in the Dinosaur Workshop.'

0:16:43 > 0:16:48It doesn't matter whether you're a bunch of hungry tyrannosaurs,

0:16:48 > 0:16:52a nothronychus, or me, a human being. You've got to eat to survive.

0:16:52 > 0:16:54Now, for a human being like me,

0:16:54 > 0:16:57every day I'm going to consume something like this.

0:16:57 > 0:17:00Rice, pasta, egg, fruit and vegetables.

0:17:00 > 0:17:04It's got add up to enough energy for me to do what I need to do.

0:17:04 > 0:17:07But what would a one-tonne dinosaur have to eat?

0:17:07 > 0:17:09Now, remember,

0:17:09 > 0:17:13Nothronychus is descended from a long line of big carnivores

0:17:13 > 0:17:15and they ate meat. Lots of it.

0:17:15 > 0:17:19A typical one-tonne meat-eater would be getting through

0:17:19 > 0:17:26around about ten kilos of flesh every single day.

0:17:26 > 0:17:33So, that's like this lot and, probably, my leg into the bargain.

0:17:35 > 0:17:39Now, that may look like an awful lot to consume

0:17:39 > 0:17:41until you remember Nothronychus is trying to get

0:17:41 > 0:17:45this amount of energy just by eating plant matter.

0:17:45 > 0:17:48And vegetation just isn't as energy-dense as meat.

0:17:48 > 0:17:52You've got to roughly eat five times as much to get what you need.

0:17:52 > 0:17:57So, every day, a nothronychus would be trying to get through that.

0:17:57 > 0:18:03And probably that. And probably that. And maybe that too.

0:18:03 > 0:18:07It is an absolute stack of vegetation to chomp your way through

0:18:07 > 0:18:08every single day.

0:18:08 > 0:18:11Which is probably why Nothronychus was renowned

0:18:11 > 0:18:13for its large potbelly.

0:18:13 > 0:18:17It had an awful lot to fit in. But why would it bother?

0:18:17 > 0:18:20Well, by eating vegetables, it didn't have to compete

0:18:20 > 0:18:24with all the large carnivores eating meat.

0:18:25 > 0:18:27Easy, tiger.

0:18:42 > 0:18:44This is Argentinosaurus.

0:18:44 > 0:18:47A massive, plant-eating dinosaur

0:18:47 > 0:18:52that lived 95 million years ago in South America.

0:18:52 > 0:18:55They were huge. But their babies were tiny,

0:18:55 > 0:18:57weighing only five kilograms.

0:18:57 > 0:19:00That's about the same as a one-month-old human child.

0:19:00 > 0:19:06But fully-grown Argentinosaurs could weigh as much as 75,000 kilos.

0:19:06 > 0:19:10That's heavier than the combined weight

0:19:10 > 0:19:14of all the children in a typical primary school.

0:19:14 > 0:19:17This dinosaur is the largest creature

0:19:17 > 0:19:19known to have walked our planet.

0:19:19 > 0:19:23Being so big meant that any other dinosaur that got too close

0:19:23 > 0:19:27to Argentinosaurus could be in real danger.

0:19:55 > 0:19:57It's almost impossible

0:19:57 > 0:20:01to comprehend the size of these enormous creatures.

0:20:06 > 0:20:10Maybe this argentinosaurus leg bone could help you get an idea.

0:20:11 > 0:20:13It weighs half a tonne.

0:20:14 > 0:20:17It's one of many found in Argentina in 1993.

0:20:19 > 0:20:22Just that single lower leg bone, which would be the shinbone

0:20:22 > 0:20:27for a human, is, incredibly, taller than an average 13-year-old.

0:20:27 > 0:20:29Or, to put it another way,

0:20:29 > 0:20:34a fully-grown argentinosaur weighed as much as ten elephants.

0:20:49 > 0:20:52Meet Epidexipteryx.

0:20:52 > 0:20:56A very strange-looking, pigeon-sized creature

0:20:56 > 0:21:00that you would have found in lush forests like this

0:21:00 > 0:21:02154 million years ago.

0:21:05 > 0:21:07This dinosaur lived in Asia.

0:21:08 > 0:21:10It was small, only half a metre long

0:21:10 > 0:21:13from its head to the tip of its tail.

0:21:14 > 0:21:16And it had a bird-like skeleton,

0:21:16 > 0:21:18covered in feathers.

0:21:19 > 0:21:23Epidexipteryxs were dinosaurs like no others.

0:21:23 > 0:21:25Everything about them is weird.

0:21:25 > 0:21:28The tongue-twisting name, the long tail feathers,

0:21:28 > 0:21:30sticky-out teeth,

0:21:30 > 0:21:33and, especially, those spindly fingers.

0:21:33 > 0:21:37Those fingers, though, are for more than just climbing trees.

0:21:37 > 0:21:39Watch this.

0:21:40 > 0:21:43That third finger on both its clawed hands

0:21:43 > 0:21:45is much longer than all the others.

0:21:45 > 0:21:49It's a tool Epidex uses in a very clever way.

0:21:49 > 0:21:53For getting at food hidden inside the tree.

0:21:59 > 0:22:02Amazingly, there is actually an animal today

0:22:02 > 0:22:06that uses the very same weird method for getting its dinner.

0:22:07 > 0:22:09This is an aye-aye.

0:22:09 > 0:22:13It's a small mammal that lives in Madagascar off the coast of Africa.

0:22:16 > 0:22:20Just like Epidex, it has a very long third finger.

0:22:20 > 0:22:22It taps on the tree and listens.

0:22:24 > 0:22:28When it hears something inside, it scrapes away at the bark,

0:22:28 > 0:22:31hoping to get some juicy insects to eat.

0:22:34 > 0:22:38'Time for me to turn myself into a very strange creature.'

0:22:38 > 0:22:41Ha-ha!

0:22:48 > 0:22:51Epidexipteryx had probably the weirdest set of hands

0:22:51 > 0:22:53I've ever seen.

0:22:53 > 0:22:56It kind of had these two shorter talons

0:22:56 > 0:22:59and then this one ludicrously long finger.

0:22:59 > 0:23:02Its way of life was to climb trees and eat grubs.

0:23:02 > 0:23:04Now, what I want to do is get an idea

0:23:04 > 0:23:07of what that would have been like,

0:23:07 > 0:23:11and the strengths and weaknesses of the features it had evolved.

0:23:11 > 0:23:14So, I'm going to set off as a normal person

0:23:14 > 0:23:16to live the life of an epidexipteryx.

0:23:16 > 0:23:18Got myself a jungle, here,

0:23:18 > 0:23:21hopefully there's some food in there somewhere.

0:23:21 > 0:23:23I'm going to see if I can find it.

0:23:25 > 0:23:28When it comes to climbing, our hands are actually pretty good.

0:23:28 > 0:23:32We've got sort of short, stubby, strong fingers that can grip

0:23:32 > 0:23:36and move our way up through trees pretty effectively.

0:23:36 > 0:23:37But what about foraging for food?

0:23:37 > 0:23:40If I wanted to find maybe a big, fat, tasty grub to eat,

0:23:40 > 0:23:42what are my hands like then?

0:23:44 > 0:23:47Ha-ha. In here. I see some food.

0:23:47 > 0:23:49There's a little grub in this log.

0:23:53 > 0:23:57The problem is, our strong, stubby fingers haven't got the length

0:23:57 > 0:24:00to get into little nooks and crannies to pull grubs out.

0:24:00 > 0:24:02What I need is a new set of hands.

0:24:04 > 0:24:06On with my epidexipteryx gloves.

0:24:10 > 0:24:12Argh.

0:24:12 > 0:24:15What I find, climbing as an epidexipteryx,

0:24:15 > 0:24:18I've got to climb in a different way.

0:24:18 > 0:24:22Because I've only got three fingers, I've got to use my feet more

0:24:22 > 0:24:24cos, even with my fingers,

0:24:24 > 0:24:26only two of them are any good for gripping.

0:24:26 > 0:24:30This third one feels like a positive disadvantage on the climbing front.

0:24:30 > 0:24:31But I'm getting used to it.

0:24:31 > 0:24:35Now, I'm going to get up here, towards where the food is.

0:24:39 > 0:24:42Now, now I can see this big fella coming into its own.

0:24:42 > 0:24:47Cos that little nest of grubs are now all within reach.

0:24:49 > 0:24:54Oh, got it. Come on. Look at that!

0:24:54 > 0:24:59Now, I really am beginning to enjoy life as an epidexipteryx.

0:25:03 > 0:25:06There are so many strange things about Epidexipteryx,

0:25:06 > 0:25:08aren't there?

0:25:08 > 0:25:12I mean, how can we be sure that a dinosaur like this really existed?

0:25:12 > 0:25:15By taking a look at the evidence, that's how.

0:25:18 > 0:25:22This extraordinary fossil was discovered recently in China.

0:25:23 > 0:25:28It shows a whole epidexipteryx. Its bird-like appearance is clear.

0:25:28 > 0:25:31As are its odd-looking teeth on its skull.

0:25:32 > 0:25:35You can even see the long tail feathers.

0:25:37 > 0:25:41Epidexipteryx was about the size of a pigeon.

0:25:41 > 0:25:44But a pigeon's feathers help it to fly.

0:25:49 > 0:25:52The feathers on this dinosaur were for display.

0:25:52 > 0:25:54In other words, showing off.

0:26:10 > 0:26:12This is one of the strangest dinosaurs

0:26:12 > 0:26:15to have walked our planet.

0:26:15 > 0:26:17Meet Gigantoraptor.

0:26:17 > 0:26:19A breathtaking creature,

0:26:19 > 0:26:24with a body like a huge, overgrown ostrich,

0:26:24 > 0:26:28and a head with a fearsome, parrot-like beak.

0:26:28 > 0:26:32It's the largest feathered animal ever discovered.

0:26:34 > 0:26:38Gigantoraptor was one-and-a-half tonnes in weight

0:26:38 > 0:26:39and a massive eight metres long.

0:26:39 > 0:26:43It had vicious, dagger-like claws,

0:26:43 > 0:26:45and lived 80 million years ago.

0:26:53 > 0:26:56Gigantoraptors were to be found in Asia,

0:26:56 > 0:26:59roughly where you'd find Mongolia today.

0:26:59 > 0:27:03They come from a family of dinosaurs known as oviraptorids.

0:27:03 > 0:27:06But Gigantoraptor was by far and away

0:27:06 > 0:27:09the biggest member of this strange family.

0:27:09 > 0:27:13How do we know such an odd creature ever existed?

0:27:13 > 0:27:18By taking a look at the evidence, that's how.

0:27:21 > 0:27:24This is the Gobi Desert in Mongolia, Asia.

0:27:24 > 0:27:28In 2007, the bones of a gigantoraptor were discovered here.

0:27:30 > 0:27:35They were huge. 35 times bigger than any other of its close relatives.

0:27:39 > 0:27:41It's their sheer size that's incredible.

0:27:43 > 0:27:45It looks a bit like an ostrich.

0:27:46 > 0:27:50But it would need four ostriches standing on top each other

0:27:50 > 0:27:53to match the height of a gigantoraptor.

0:27:59 > 0:28:01We know that gigantoraptors had feathers

0:28:01 > 0:28:04because they've been found on the fossils

0:28:04 > 0:28:07of other closely-related dinosaurs.

0:28:07 > 0:28:10But Gigantoraptor's feathers weren't for flying -

0:28:10 > 0:28:12nor were they for keeping warm.

0:28:12 > 0:28:16These were feathers for display - especially for attracting a mate.

0:28:18 > 0:28:22Here, a male and female gigantoraptor

0:28:22 > 0:28:24are doing a kind of dance.

0:28:32 > 0:28:36It's a bit like showing off your best dance moves

0:28:36 > 0:28:37at the school disco.

0:28:40 > 0:28:43Now, if that sounds just too far-fetched,

0:28:43 > 0:28:45take a look at these grebes.

0:28:48 > 0:28:49Just like the gigantoraptors,

0:28:49 > 0:28:53they're carrying out what's called a courtship dance.

0:28:53 > 0:28:55They move in time, display their feathers

0:28:55 > 0:28:58and copy each other's movements.

0:28:58 > 0:29:02The aim is to find and, hopefully, attract a mate.

0:29:05 > 0:29:09Gigantoraptor's similarity to birds really stands out

0:29:09 > 0:29:14but there's more to this resemblance than feathers and beaks.

0:29:15 > 0:29:18That's because they laid eggs.

0:29:20 > 0:29:23This is how all dinosaurs gave birth.

0:29:23 > 0:29:28What's special about Gigantoraptor is that it stayed with its eggs,

0:29:28 > 0:29:29protecting them.

0:29:29 > 0:29:34Here, a pair of gigantoraptors defend their nest

0:29:34 > 0:29:37against an attack from this predator - Alectrosaurus.

0:29:50 > 0:29:52Danger over.

0:29:52 > 0:29:56The mother gigantoraptor settles back down on her nest.

0:30:00 > 0:30:03'Meanwhile, in the Dinosaur Workshop,

0:30:03 > 0:30:07- 'I'm- hatching- a very - egg-citing- plan.

0:30:07 > 0:30:08'Yeah, er, sorry.'

0:30:08 > 0:30:11There is one thing that all dinosaurs have in common.

0:30:11 > 0:30:13They lay eggs.

0:30:13 > 0:30:15And, in the case of the gigantoraptor,

0:30:15 > 0:30:17eggs like I have never seen before.

0:30:17 > 0:30:21To show you how odd they are, let's first look at more familiar eggs.

0:30:21 > 0:30:24That's a chicken's egg. We all know what these are like.

0:30:24 > 0:30:28They're three centimetres long. We have them for breakfast.

0:30:28 > 0:30:31This is an ostrich egg.

0:30:31 > 0:30:35This is the biggest egg that's laid on the planet in modern times.

0:30:35 > 0:30:40It's a pretty good size and it comes from a pretty good-sized bird.

0:30:40 > 0:30:44And this is a genuine dinosaur egg.

0:30:44 > 0:30:46Or, at least, a fossil of one.

0:30:46 > 0:30:50This would have been laid in muddy ground about 70 million years ago.

0:30:50 > 0:30:54And, over that time, the mud has turned into rock

0:30:54 > 0:30:56and the egg has turned into a fossil.

0:30:56 > 0:31:02And this is our gigantoraptor egg. I say "ours" because we've made it.

0:31:02 > 0:31:04But we've made it very carefully,

0:31:04 > 0:31:07to be the right size, shape and strength

0:31:07 > 0:31:11to match fossilised gigantoraptor eggs that were recently found.

0:31:11 > 0:31:14These eggs took about 80 days to hatch.

0:31:14 > 0:31:16Now, that is a long time

0:31:16 > 0:31:19for it to be exposed to potential predators.

0:31:19 > 0:31:23So, they would have to have been made pretty strong. How strong?

0:31:23 > 0:31:24Let's find out.

0:31:26 > 0:31:30Naturally, my fellow dino engineers, Andy and Jim,

0:31:30 > 0:31:35are filling my gigantoraptor egg with white and yolk.

0:31:35 > 0:31:38This is my egg-strength testing machine.

0:31:38 > 0:31:41Gigantoraptor egg is up there.

0:31:41 > 0:31:46Whatever weight gets loaded on here gets felt by the egg up there.

0:31:46 > 0:31:50When this weight here gets too much for that egg...

0:31:50 > 0:31:52First...

0:31:53 > 0:31:55These bags weigh 25 kilos.

0:31:57 > 0:31:59And the egg doesn't care about that.

0:31:59 > 0:32:01Looks like I might have to get involved, here.

0:32:01 > 0:32:03Not in my best T-shirt.

0:32:07 > 0:32:09I'm 75 kilos.

0:32:11 > 0:32:13100 kilos

0:32:13 > 0:32:16on our gigantoraptor egg.

0:32:17 > 0:32:18More weight.

0:32:25 > 0:32:26That's 125 kilos.

0:32:26 > 0:32:30Now, dinosaur experts did reckon that these eggs

0:32:30 > 0:32:32would probably have taken that,

0:32:32 > 0:32:35but they weren't sat underneath the egg at the time. More weight?

0:32:36 > 0:32:40'This gigantoraptor egg is living up to its tough reputation.'

0:32:44 > 0:32:46That's 150 kilos.

0:32:49 > 0:32:50CRACK

0:32:53 > 0:32:55LAUGHTER

0:32:56 > 0:32:57Argh!

0:32:57 > 0:32:59Argh!

0:33:04 > 0:33:07Right. Well, that's a nice piece of science,

0:33:07 > 0:33:08cos that egg pretty much fitted

0:33:08 > 0:33:12with what the dinosaur experts reckoned the Gigantoraptor egg

0:33:12 > 0:33:14would have taken.

0:33:26 > 0:33:29We're going to look at the bite strength

0:33:29 > 0:33:32of three very powerful dinosaurs.

0:33:33 > 0:33:35Allosaurus.

0:33:35 > 0:33:38Majungasaurus.

0:33:38 > 0:33:40And Daspletosaurus.

0:33:41 > 0:33:45All of them are big predators with terrifying jaws.

0:33:45 > 0:33:49Just imagine them clamped tight round your leg.

0:33:49 > 0:33:54How much force do you think it would take to prise them back open?

0:33:54 > 0:33:58'Let's find out in the Planet Dinosaur Files Workshop.'

0:34:04 > 0:34:05Now, obviously,

0:34:05 > 0:34:08a dinosaur's jaws are what's really scary about these beasts.

0:34:08 > 0:34:12But I want to know is just how powerful those jaws are.

0:34:12 > 0:34:15To do that, I've built my own dinosaur jaws.

0:34:17 > 0:34:20My first set of experimental jaws are going to recreate

0:34:20 > 0:34:23the bite of an allosaurus,

0:34:23 > 0:34:28a muscle-bound, meat-eating dinosaur that lived 150 million years ago,

0:34:28 > 0:34:30roughly where the USA is today.

0:34:31 > 0:34:34This is my allosaurus.

0:34:34 > 0:34:37And this is what's driving the bite of the allosaurus.

0:34:39 > 0:34:41It works off compressed air, like this.

0:34:41 > 0:34:44I'm using air to force my jaw shut

0:34:44 > 0:34:49by squeezing it into this rubber tube at high pressure.

0:34:49 > 0:34:52At the moment, I've got it set to what dinosaur experts reckon

0:34:52 > 0:34:56is the muscle strength in an allosaurus's jaw.

0:34:56 > 0:35:01Now, I figure a good test to see how powerful a bite these fellas had

0:35:01 > 0:35:04is to stuff something in its jaws,

0:35:04 > 0:35:07get them to clamp down with full biting strength

0:35:07 > 0:35:10and then see what it takes to wrestle the jaws back open.

0:35:10 > 0:35:14Chris, do want to give that full allosaurus strength?

0:35:15 > 0:35:19Right, it's now clamped down on my trusty broom. Can I get it back?

0:35:21 > 0:35:23No.

0:35:23 > 0:35:26It turns out there's no way...

0:35:26 > 0:35:29an 11-stone bloke...

0:35:30 > 0:35:35..can get the jaws of an allosaurus open once it's bitten down.

0:35:35 > 0:35:36What about two blokes?

0:35:39 > 0:35:44Obviously, out in the wild, that would be a very dangerous manoeuvre.

0:35:44 > 0:35:47Right, see if we can get this open. Oh, my life!

0:35:56 > 0:35:58It's not easy.

0:35:58 > 0:36:01That is an incredibly powerful bite,

0:36:01 > 0:36:03but two full-grown blokes

0:36:03 > 0:36:08can just about wrestle open the jaw of a full-grown allosaurus.

0:36:11 > 0:36:15Here's another powerful prehistoric carnivore.

0:36:15 > 0:36:18This is Majungasaurus,

0:36:18 > 0:36:23a scavenging predator that lived 70 million years ago

0:36:23 > 0:36:26on the island of Madagascar, off the east coast of Africa.

0:36:28 > 0:36:31Although it was big, weighing well over a tonne,

0:36:31 > 0:36:34Majungasaurus was actually smaller than Allosaurus.

0:36:35 > 0:36:38So, how does it compare in jaw power?

0:36:40 > 0:36:43'Back to the dinosaur workshop.'

0:36:43 > 0:36:46Time to test out the majungasaurus jaws.

0:36:46 > 0:36:49Now, I've got the same powerful artificial muscle as before,

0:36:49 > 0:36:52but I've slightly reduced the head size.

0:36:52 > 0:36:56These animals were a little bit smaller than the allosaurus,

0:36:56 > 0:36:58but they had a powerful reputation.

0:36:58 > 0:37:01Jaws are set to majungasaurus strength.

0:37:01 > 0:37:04Although ordinarily a vicious meat-eater,

0:37:04 > 0:37:08it's time the majungasaurus had one of its five a day.

0:37:15 > 0:37:17I think it quite likes them!

0:37:17 > 0:37:22What will it take to prise open the mouth of a majungasaurus?

0:37:22 > 0:37:24- Ready?- Yeah.

0:37:32 > 0:37:36It's slightly mad just how hard that bite is.

0:37:36 > 0:37:41There's absolutely no way that both of us are getting that open.

0:37:41 > 0:37:43I think this needs something a bit more than human.

0:37:43 > 0:37:47'Where manpower fails, maybe van power will succeed?'

0:37:47 > 0:37:51Are you good? Start taking that away.

0:37:56 > 0:37:58Have you got any more?

0:38:03 > 0:38:05Yes, you've got it!

0:38:08 > 0:38:10Well, there we go.

0:38:10 > 0:38:12The majungasaurus - too much for a man,

0:38:12 > 0:38:14about right for a man and a van.

0:38:17 > 0:38:21Time to ratchet up the power factor with my third and final dinosaur.

0:38:24 > 0:38:25Meet Daspletosaurus.

0:38:27 > 0:38:31This intimidating beast lived 75 million years ago

0:38:31 > 0:38:34in what today is Canada.

0:38:34 > 0:38:36Adult daspletosaurs could be up to nine metres long

0:38:36 > 0:38:39and three tonnes in weight.

0:38:39 > 0:38:42That's bigger than Allosaurus and Majungasaurus put together.

0:38:43 > 0:38:46So, how will the jaws of this hefty hunter

0:38:46 > 0:38:49compare with our other two predators?

0:38:51 > 0:38:53This is my daspletosaurus.

0:38:53 > 0:38:57Even in dinosaur terms, these things were veritable monsters.

0:38:57 > 0:39:00They were like the granddaddy of T-rex.

0:39:00 > 0:39:01Now, as you can see,

0:39:01 > 0:39:04it's a much, much bigger animal

0:39:04 > 0:39:07than either the allosaurus or the majungasaurus.

0:39:07 > 0:39:10In order for us to replicate that bite force with our model,

0:39:10 > 0:39:14we had to take the whole rig right up to maximum.

0:39:14 > 0:39:17Chris, do you want to power it up?

0:39:22 > 0:39:25That's a concrete brick wedged in our daspletosaur jaws.

0:39:25 > 0:39:29Right. That's down pretty hard.

0:39:29 > 0:39:34So, what will it take to force open the jaws of a daspletosaurus?

0:39:34 > 0:39:37- Jim, shall we try by hand? - OK, ready?

0:39:39 > 0:39:42Right, it's kind of obvious that this thing

0:39:42 > 0:39:45is well beyond the means of human power.

0:39:51 > 0:39:54But the van's not doing the trick either.

0:39:56 > 0:39:57That's pretty shocking,

0:39:57 > 0:40:01because we went to great lengths to build this to accurately reflect

0:40:01 > 0:40:05what experts think these dinosaurs were capable of.

0:40:05 > 0:40:06Headline news -

0:40:06 > 0:40:10you can't even open the jaw of a daspletosaurus with a van.

0:40:13 > 0:40:15I think we need some professional help.

0:40:15 > 0:40:19What I've got is a daspletosaurus biting down at full power.

0:40:19 > 0:40:21And you're sure your little dinosaur

0:40:21 > 0:40:25- is going to be more powerful than my big dinosaur?- I'd imagine so.

0:40:25 > 0:40:27What do you normally use those for?

0:40:27 > 0:40:30It's a hydraulic spreader, mainly used for car crashes,

0:40:30 > 0:40:33so we can rescue people stuck in cars.

0:40:33 > 0:40:34To get these in here,

0:40:34 > 0:40:37- I'm going to have to do a bit of dentistry, aren't I?- I'd say so.

0:40:37 > 0:40:41Cleanliness is important in dentistry.

0:40:41 > 0:40:45Don't worry, big fella, this shouldn't hurt at all.

0:40:46 > 0:40:48Stay being brave!

0:40:51 > 0:40:53Sparky, can you do a job for us?

0:40:53 > 0:40:56OK. Fire it up.

0:40:59 > 0:41:04So, will these jaws finally meet their match?

0:41:07 > 0:41:10'It's taken that super-powerful fireman's gadget,

0:41:10 > 0:41:13'capable of shifting the weight of two double-decker buses,

0:41:13 > 0:41:16'to get those jaws open.'

0:41:16 > 0:41:17I'm seriously impressed.

0:41:17 > 0:41:20I don't want to hold you up from fighting fires.

0:41:20 > 0:41:23- Thank you ever so much.- Cheers.

0:41:23 > 0:41:26Looks like we've finally overcome the daspletosaurus.

0:41:26 > 0:41:28It appears as though normal people can't do it -

0:41:28 > 0:41:31if Daspletosaurus bites down on something,

0:41:31 > 0:41:34better call the fire service.

0:41:47 > 0:41:50'Down at my local swimming pool,

0:41:50 > 0:41:53'we're going to look at the swimming technique

0:41:53 > 0:41:55'of three prehistoric predators.'

0:41:55 > 0:41:58Kimmerosaurus.

0:41:59 > 0:42:02Sarchosuchus.

0:42:02 > 0:42:04And Predator X.

0:42:07 > 0:42:11First up is Kimmerosaurus.

0:42:11 > 0:42:16This sea beast roamed our oceans 150 million years ago

0:42:16 > 0:42:20at a time when the whole continent of Europe was covered in water.

0:42:21 > 0:42:24Kimmerosaurus was a type of prehistoric sea creature

0:42:24 > 0:42:26called a plesiosaur.

0:42:28 > 0:42:32It was six metres long - the length of a killer whale -

0:42:32 > 0:42:35and this ocean predator liked to hunt sharks.

0:42:37 > 0:42:40Kimmerosaurus lived millions of years ago,

0:42:40 > 0:42:45but it swam in a way familiar to creatures in our oceans today.

0:42:50 > 0:42:54These sea-lions have four fins,

0:42:54 > 0:42:55like Kimmerosaurus.

0:42:55 > 0:42:58And, a very similar swimming technique.

0:43:01 > 0:43:03And look at these penguins.

0:43:03 > 0:43:07We all know those stubby wings don't get them airborne,

0:43:07 > 0:43:10but once they go underwater, it's almost like they're flying.

0:43:10 > 0:43:13Look how nippy they are.

0:43:16 > 0:43:19'Now, let's head to the swimming pool to find out more about

0:43:19 > 0:43:22'how Kimmerosaurus moved through the water.'

0:43:25 > 0:43:28So, how good was a kimmerosaur's swimming technique?

0:43:28 > 0:43:32Well, I'm going to try and find out in this swimming pool.

0:43:32 > 0:43:36I can swim backstroke, front crawl and things like that,

0:43:36 > 0:43:39but I haven't got the equipment to swim like a kimmerosaurus.

0:43:39 > 0:43:42So, we've built this.

0:43:42 > 0:43:45It may look a bit big and bulky, but actually,

0:43:45 > 0:43:48it's only about half the size of the real thing.

0:43:48 > 0:43:52And a kimmerosaurus didn't swim front crawl, like that.

0:43:53 > 0:43:56The kimmerosaurus used wings.

0:43:56 > 0:43:59What they used to do was sort of flap these wings in the water

0:43:59 > 0:44:03to propel themselves at great speed underwater.

0:44:03 > 0:44:06Jim and I, the muscles of the kimmerosaurus,

0:44:06 > 0:44:10can't spend much time underwater because of our lungs,

0:44:10 > 0:44:12but we can operate these wings.

0:44:14 > 0:44:16- Ready, Jim?- Yeah.- Let's go.

0:44:16 > 0:44:20We're timing how long it takes our kimmerosaurus swimming model

0:44:20 > 0:44:23to get down this 25-metre pool.

0:44:23 > 0:44:27Just how good are those underwater wings?

0:44:48 > 0:44:52That's pretty astonishing.

0:44:52 > 0:44:56Just these four flapping fins have managed to get

0:44:56 > 0:44:58well over a quarter of a tonne of boat and rider

0:44:58 > 0:45:03down a swimming pool in less than 45 seconds.

0:45:03 > 0:45:07Obviously, a real kimmerosaur would be a lot smoother,

0:45:07 > 0:45:10because they swam under the water.

0:45:10 > 0:45:12They didn't have a big, bulky boat with them.

0:45:12 > 0:45:16I think it is a very effective swimming technique.

0:45:20 > 0:45:24Our next prehistoric swimmer is this terrifying river beast.

0:45:25 > 0:45:30Meet the king of the crocodiles, Sarchosuchus.

0:45:30 > 0:45:33Its name means "flesh crocodile"

0:45:33 > 0:45:37and it lived 95 million years ago in North Africa.

0:45:41 > 0:45:43An enormous 12 metres long -

0:45:43 > 0:45:47that's the length of a whole railway carriage.

0:45:47 > 0:45:49Heavier than a fully-grown elephant,

0:45:49 > 0:45:53weighing an astonishing eight tonnes.

0:45:53 > 0:45:57Twice the size of any crocodile in the world today.

0:45:57 > 0:45:59This is a super crocodile.

0:46:05 > 0:46:09Sarchosuchus, like all crocodiles,

0:46:09 > 0:46:12was perfectly adapted to living in water.

0:46:12 > 0:46:16True, crocodiles do have to come to the surface to breathe,

0:46:16 > 0:46:18but they've evolved to be able to spend

0:46:18 > 0:46:21staggering lengths of time underwater.

0:46:21 > 0:46:25If they're not moving, they can spend several hours

0:46:25 > 0:46:28beneath the surface without needing to come up for air.

0:46:28 > 0:46:32They also have a special way of swimming that's different to

0:46:32 > 0:46:37sea lions or Kimmerosaurus, the plesiosaur we've already met.

0:46:37 > 0:46:41A crocodile's body and tail moves in a sideways action,

0:46:41 > 0:46:45making a kind of S shape through the water.

0:46:48 > 0:46:53'Let's find out just how effective that method was in practice.'

0:46:56 > 0:47:01OK, now let's see how quick it is swimming like a sarchosuchus.

0:47:01 > 0:47:03First, I need a very long tail.

0:47:07 > 0:47:12Next, I want to make myself look as frightening and sleek as possible.

0:47:15 > 0:47:17And finally, to be a top predator,

0:47:17 > 0:47:19you need to be able to see underwater.

0:47:22 > 0:47:26That's it. Sarchosuchus.

0:47:26 > 0:47:31Sarchosuchus swims in a very different style to Kimmerosaurus.

0:47:31 > 0:47:34How will it compare for speed?

0:47:54 > 0:47:56That is astonishingly quick.

0:47:56 > 0:47:59That is twice the speed of a kimmerosaurus and the thing is,

0:47:59 > 0:48:02once you get one of these big crocodile tails on,

0:48:02 > 0:48:05you can feel the power in the water.

0:48:05 > 0:48:09You can use every muscle in your body to propel yourself along

0:48:09 > 0:48:12and that's why the sarchosuchus must have been

0:48:12 > 0:48:16one of the most feared predators in prehistoric waters.

0:48:26 > 0:48:28Here is our final aquatic contender.

0:48:28 > 0:48:30Recently discovered,

0:48:30 > 0:48:33it's so fearsome that even its name is terrifying.

0:48:35 > 0:48:37This is Predator X,

0:48:37 > 0:48:39a truly enormous monster.

0:48:42 > 0:48:46More than 15 metres long and a massive 45 tonnes.

0:48:48 > 0:48:53Nearly five times the weight of the largest known killer whale.

0:48:53 > 0:48:56It had jaws more powerful than any dinosaur.

0:49:00 > 0:49:04Predator X lived 150 million years ago

0:49:04 > 0:49:07in the same seas as Kimmerosaurus

0:49:07 > 0:49:09and it's likely that Kimmerosaurus

0:49:09 > 0:49:13was top of the menu for this ocean monster.

0:49:15 > 0:49:20Now, often in the water, smaller can seem faster.

0:49:20 > 0:49:25And as Predator X is three times bigger than Kimmerosaurus,

0:49:25 > 0:49:27you might think that Kimmerosaurus

0:49:27 > 0:49:30would be able to outswim this huge hunter.

0:49:30 > 0:49:33Let's find out if that really is the case.

0:49:35 > 0:49:39Time to bring a bit of Predator X to the local swimming pool.

0:49:39 > 0:49:43Now, in swimming style, he's pretty much the same as Kimmerosaurus -

0:49:43 > 0:49:47four large fins flying through the water.

0:49:47 > 0:49:50Significant difference - he's much, much bigger.

0:49:50 > 0:49:53There's the little old Kimmerosaurus one,

0:49:53 > 0:49:55here's the big Predator X one.

0:49:55 > 0:49:59Whereas Kimmerosaurus was about the size of a killer whale,

0:49:59 > 0:50:00this thing, in real life,

0:50:00 > 0:50:03would have been about the size of this swimming pool.

0:50:03 > 0:50:06So, how will our Predator X get on?

0:50:12 > 0:50:16'Once we get those massive fins into a rhythm,

0:50:16 > 0:50:19'Predator X eats up the water.'

0:50:35 > 0:50:38Just over 30 seconds. This thing's quick.

0:50:38 > 0:50:40It's not quite as quick as Sarchosuchus,

0:50:40 > 0:50:42which was very swift off the mark,

0:50:42 > 0:50:45but noticeably faster than Kimmerosaurus.

0:50:45 > 0:50:47The fact is, the way it felt here,

0:50:47 > 0:50:52Jim and I just don't have the power for water wings this big.

0:50:52 > 0:50:54And the difference is,

0:50:54 > 0:50:58real-life Predator X was a veritable monster.

0:50:58 > 0:51:02It was like a 45-tonne torpedo and it had all the strength

0:51:02 > 0:51:05it needed to drive its massive wings through the water,

0:51:05 > 0:51:09giving it the ability to devour just about anything it wanted.

0:51:27 > 0:51:30This is the island of Madagascar off the coast of Africa,

0:51:30 > 0:51:3270 million years ago.

0:51:32 > 0:51:38A family of scavenging majungasaurs, a mother and two youngsters,

0:51:38 > 0:51:39are feeding off a carcass.

0:51:39 > 0:51:45Suddenly, another big meat-eating dinosaur arrives on the scene.

0:51:45 > 0:51:47Another majungasaurus.

0:51:50 > 0:51:54It's a male, and he wants to muscle in on this feast.

0:51:56 > 0:52:00Our majungasaur mum has her kids to think of. They need food.

0:52:03 > 0:52:07But this male is greedy. He wants all that meat for himself.

0:52:08 > 0:52:12He won't even let the youngster have the scraps.

0:52:18 > 0:52:20Now, take a look at this fossil.

0:52:21 > 0:52:25This is the tail bone of a majungasaurus,

0:52:25 > 0:52:28discovered on Madagascar in 2003.

0:52:30 > 0:52:35Take a very close look. There are some revealing marks on it.

0:52:35 > 0:52:39What do you think those marks are, and how might they have got there?

0:52:43 > 0:52:46Here's one possible answer.

0:52:46 > 0:52:49They came from the teeth of another majungasaurus,

0:52:49 > 0:52:54caused maybe during a fight between two of these dinosaurs

0:52:54 > 0:52:57that has left the scars of battle.

0:52:57 > 0:53:00But things aren't always what they seem.

0:53:02 > 0:53:05Dinosaur experts discovered these were bite marks -

0:53:05 > 0:53:08another majungasaur's bite marks.

0:53:10 > 0:53:13But this didn't look like a fight between two angry predators.

0:53:13 > 0:53:17This was one majungasaur eating the other.

0:53:20 > 0:53:24So it seems that majungasaurs could be cannibals.

0:53:24 > 0:53:29When the female majungasaur finally finishes off the male,

0:53:29 > 0:53:32it doesn't go back to that carcass.

0:53:32 > 0:53:36Instead, it starts eating the body of the male majungasaur.

0:53:37 > 0:53:40If that seems shocking, maybe unbelievable,

0:53:40 > 0:53:43then just take a look at our world today.

0:53:45 > 0:53:50These insects are praying mantises. A male and a female.

0:53:50 > 0:53:51They're mating.

0:53:51 > 0:53:55But then the female starts eating the male's head.

0:53:56 > 0:54:00Mantises, just like majungasaurs, can turn into cannibals

0:54:00 > 0:54:03when they're hungry.

0:54:19 > 0:54:23Meet Spinosaurus, a huge dinosaur.

0:54:23 > 0:54:2617 metres long and 12 tonnes in weight.

0:54:28 > 0:54:34This incredible predator lived 95 million years ago in North Africa.

0:54:34 > 0:54:36You would typically find this dinosaur

0:54:36 > 0:54:39standing in the shallows of a river.

0:54:41 > 0:54:46Here, our spinosaurus has got its eyes on something in the water.

0:54:49 > 0:54:53Now, take a look at this piece of bone evidence.

0:54:53 > 0:54:57These are the tooth sockets in a spinosaurus's jaw.

0:54:57 > 0:55:00It was found in 2005 in North Africa.

0:55:00 > 0:55:03Stuck in one of the sockets

0:55:03 > 0:55:06is a tiny piece of backbone from another creature.

0:55:07 > 0:55:12How do you think that fragment of bone got into Spino's jaw,

0:55:12 > 0:55:16and what type of creature might that bone have come from?

0:55:17 > 0:55:22Well, here are four possible prehistoric suspects.

0:55:22 > 0:55:25They're all creatures that lived in water.

0:55:25 > 0:55:29There's Kimmerosaurus, Predator X,

0:55:29 > 0:55:34Sarcosuchus and Onchopristis.

0:55:34 > 0:55:35Which one is it?

0:55:41 > 0:55:43Let's look at our suspects.

0:55:43 > 0:55:46Well, both Kimmerosaurus and Predator X

0:55:46 > 0:55:51lived 55 million years before Spinosaurus was around.

0:55:51 > 0:55:53They're also sea creatures,

0:55:53 > 0:55:56and Spino was a dinosaur that hunted in rivers, not oceans.

0:55:56 > 0:55:58So, that rules them out.

0:56:04 > 0:56:09And then there's Sarcosuchus, a giant prehistoric crocodile.

0:56:09 > 0:56:13This reptile lived at the same time as Spinosaurus

0:56:13 > 0:56:16and around the same North African rivers, but Sarcosuchus

0:56:16 > 0:56:19was another massive predator,

0:56:19 > 0:56:22too big for even Spinosaurus to take on.

0:56:28 > 0:56:31That leaves just this creature.

0:56:31 > 0:56:34Onchopristis, an eight metre-long sawfish.

0:56:34 > 0:56:36It was a prehistoric river fish

0:56:36 > 0:56:40that lived at the same time as Spinosaurus.

0:56:40 > 0:56:45Spino, as we know, was a dinosaur that spent a lot of time by rivers.

0:56:45 > 0:56:49Standing in the shallows, it would play a waiting game.

0:56:51 > 0:56:56Usually, it would be on the lookout for one of these, onchopristis.

0:56:56 > 0:56:58Palaeontologists, dinosaur experts,

0:56:58 > 0:57:04are convinced this kind of creature provides our answer.

0:57:04 > 0:57:09That mystery bone fragment came from a sawfish like onchopristis.

0:57:09 > 0:57:14These juicy fish were one of Spinosaurus's favourite foods.

0:57:14 > 0:57:18And a bit like a bored angler, Spino would spend hours

0:57:18 > 0:57:21waiting for these tasty river treats to swim by.

0:57:23 > 0:57:28Here was a beast that loved poking its snout into a fast-flowing river.

0:57:28 > 0:57:31When it grabbed an onchopristis in its jaws,

0:57:31 > 0:57:33it's easy to see how a piece

0:57:33 > 0:57:39of the sawfish's backbone could get stuck in Spino's tooth socket.

0:58:00 > 0:58:02Subtitles by Red Bee Media Ltd