0:00:02 > 0:00:06If you thought you knew all about dinosaurs, think again.
0:00:06 > 0:00:10This is Planet Dinosaur Files -
0:00:10 > 0:00:13the series that rewrites the prehistory books.
0:00:13 > 0:00:18We bring to life the most awesome beasts ever to walk the earth.
0:00:18 > 0:00:21With state-of-the-art CGI technology
0:00:21 > 0:00:25that makes you feel like you're right there.
0:00:25 > 0:00:29And I'll be discovering what made these massive,
0:00:29 > 0:00:32lethal and, frankly, bizarre beasts tick.
0:00:32 > 0:00:36This time, the demos get really weird.
0:00:36 > 0:00:40I'll be eating my greens, hunting for insects.
0:00:40 > 0:00:44And, when I put a dinosaur egg to the test, the yolk's on me.
0:00:44 > 0:00:46Argh!
0:00:48 > 0:00:51In the last 20 years,
0:00:51 > 0:00:53scientists have discovered more dinosaurs
0:00:53 > 0:00:57than in all the centuries that have gone before.
0:00:57 > 0:01:00Amazing new discoveries.
0:01:00 > 0:01:04They reveal a jaw-dropping cast list of creatures.
0:01:05 > 0:01:08Bigger, stranger,
0:01:08 > 0:01:11deadlier than we'd ever imagine.
0:01:11 > 0:01:14And this time, on Planet Dinosaur Files,
0:01:14 > 0:01:15I'm asking the question,
0:01:15 > 0:01:20which dinosaur was the weirdest in the prehistoric world?
0:01:29 > 0:01:31You might think you know about dinosaurs.
0:01:33 > 0:01:37Like the huge 12-tonne plant-eater, Diplodocus.
0:01:40 > 0:01:43Or the mighty Tyrannosaurus Rex,
0:01:43 > 0:01:48a savage predator who dominated on land for almost five million years.
0:01:49 > 0:01:51Well, think again.
0:01:54 > 0:01:59Now let's meet the new, weird dinos on the block.
0:02:01 > 0:02:03Like Nothronychus.
0:02:03 > 0:02:05An odd, potbellied dinosaur,
0:02:05 > 0:02:08a meat-eater that turned veggie.
0:02:08 > 0:02:10Or Epidexipteryx,
0:02:10 > 0:02:15a strange creature with a very special way of getting a meal.
0:02:15 > 0:02:18A dinosaur that lived off insects.
0:02:19 > 0:02:22And the extraordinary Gigantoraptor,
0:02:22 > 0:02:26a weird, winged wonder that couldn't actually fly.
0:02:29 > 0:02:33All these weird creatures were actually dinosaurs.
0:02:33 > 0:02:38And I'm going to compare them to see which one really stands out.
0:02:40 > 0:02:43First, size.
0:02:43 > 0:02:47These weird creatures ranged between the very big and very small.
0:02:47 > 0:02:51But what difference does their size and shape make to them as dinosaurs?
0:02:56 > 0:02:59Next, the tools they used for getting food.
0:02:59 > 0:03:02And what did they eat, and where did they find it?
0:03:02 > 0:03:04And I'll be deciding
0:03:04 > 0:03:09what really makes these creatures especially weird.
0:03:09 > 0:03:12Let's meet our first contender.
0:03:20 > 0:03:23This is Nothronychus.
0:03:23 > 0:03:26It lived in swampy jungles like this,
0:03:26 > 0:03:2892 million years ago.
0:03:31 > 0:03:32Because it walks on two legs,
0:03:32 > 0:03:36Nothronychus has the classic look of a meat-eating dinosaur.
0:03:36 > 0:03:39But it's actually a vegetarian.
0:03:40 > 0:03:45It's one of a weird group of dinosaurs called Therizinosaurs.
0:03:45 > 0:03:48Twice as tall as an adult human,
0:03:48 > 0:03:51it had a lengthy neck, and powerful legs.
0:03:53 > 0:03:56It used its very long, curved claws
0:03:56 > 0:04:01to pull down branches to get nice, juicy leaves to eat.
0:04:01 > 0:04:04In fact, its name means "sloth-like claws".
0:04:10 > 0:04:12And here's why -
0:04:12 > 0:04:15Nothro's claws are very like those of this bizarre-looking creature,
0:04:15 > 0:04:17the sloth.
0:04:18 > 0:04:22This gentle, tree-dwelling mammal lives in South America
0:04:22 > 0:04:25and it uses it claws to grab and eat leaves
0:04:25 > 0:04:28in exactly the way that Nothronychus does.
0:04:29 > 0:04:30Unlike sloths though,
0:04:30 > 0:04:34Nothronychus had to be ready to defend itself
0:04:34 > 0:04:36against some dangerous predators...
0:04:42 > 0:04:47In these same swamps is an eight-metre long Tyrannosaur.
0:04:47 > 0:04:49A fearsome carnivore
0:04:49 > 0:04:52from the same family of dinosaurs as the famous T-Rex.
0:04:53 > 0:04:57And this Tyrannosaur fancies some Nothronychus for dinner.
0:04:59 > 0:05:00And it's at times like this
0:05:00 > 0:05:03that those claws become weapons of self-defence,
0:05:03 > 0:05:06making these pot-bellied beasts
0:05:06 > 0:05:09a match for the mighty Tyrannosaurs.
0:05:09 > 0:05:15Nothronychus is just as powerful and aggressive as these killers
0:05:15 > 0:05:20and that's because they're actually close relatives...
0:05:27 > 0:05:32So if they look like a carnivore and they fight like a carnivore,
0:05:32 > 0:05:36how can we be sure that they were actually herbivores?
0:05:36 > 0:05:39By taking a look at the evidence, that's how.
0:05:41 > 0:05:46In 2001, the bones of a dinosaur very like Nothronychus
0:05:46 > 0:05:48were discovered in the USA.
0:05:49 > 0:05:52Amongst them were fossil teeth.
0:05:52 > 0:05:53Their shape showed
0:05:53 > 0:05:55they were designed for eating leaves, not meat.
0:05:57 > 0:05:58NOTHRONYCHUS ROARS
0:05:58 > 0:06:01Nothronychus, just like these Tyrannosaurs,
0:06:01 > 0:06:03started off as a meat-eating dinosaur.
0:06:03 > 0:06:07But, over hundreds of thousands years,
0:06:07 > 0:06:09Nothronychus changed its eating habits.
0:06:09 > 0:06:13It still looked like a carnivore, with its upright stance,
0:06:13 > 0:06:16but now it lived off plants.
0:06:22 > 0:06:24Time to head to the dinosaur workshop.
0:06:24 > 0:06:26Each of our weird dinos
0:06:26 > 0:06:30is going to have its own special demo.
0:06:30 > 0:06:32First stop - the kitchen!
0:06:32 > 0:06:36Now it doesn't matter whether you're a bunch of hungry Tyrannosaurs,
0:06:36 > 0:06:39a Nothronychus, or me, a human being,
0:06:39 > 0:06:41you've got to eat to survive.
0:06:41 > 0:06:43Now for a human being like me, every day,
0:06:43 > 0:06:45I've got to consume something like this.
0:06:45 > 0:06:49Rice, pasta, egg, fruit and vegetables.
0:06:49 > 0:06:51It's got to add up to enough energy
0:06:51 > 0:06:53for me to do what I need to do.
0:06:53 > 0:06:56But what would a one-tonne dinosaur have to eat?
0:06:56 > 0:06:59Now remember, Nothronychus is descended
0:06:59 > 0:07:03from a long line of big carnivores and they ate meat -
0:07:03 > 0:07:04lots of it.
0:07:04 > 0:07:06A typical one-tonne meat-eater
0:07:06 > 0:07:13would be getting through around about ten kilos of flesh,
0:07:13 > 0:07:16every single day.
0:07:16 > 0:07:19So that's like this lot, and...
0:07:20 > 0:07:24probably my leg into the bargain!
0:07:24 > 0:07:26Now that may look like an awful lot to consume,
0:07:26 > 0:07:30until you remember Nothronychus is trying to get this amount of energy
0:07:30 > 0:07:32just by eating plant matter.
0:07:34 > 0:07:37And vegetation just isn't as energy-dense as meat.
0:07:37 > 0:07:41You've got to roughly eat five times as much to get what you need.
0:07:41 > 0:07:44So every day, a Nothronychus would be trying to get through...
0:07:44 > 0:07:45that.
0:07:45 > 0:07:47And probably that.
0:07:47 > 0:07:51And probably that. And maybe that too!
0:07:51 > 0:07:56It is an absolute stack of vegetation to chomp your way through
0:07:56 > 0:07:57every single day.
0:07:57 > 0:07:59Which is probably why Nothronychus
0:07:59 > 0:08:02was renowned for its large pot-belly.
0:08:02 > 0:08:04It had an awful lot to fit in.
0:08:04 > 0:08:05But why would it bother?
0:08:05 > 0:08:07Well, by eating vegetables,
0:08:07 > 0:08:11it didn't have to compete with all the large carnivores eating meat.
0:08:12 > 0:08:14ROAR!
0:08:14 > 0:08:16Easy, tiger!
0:08:21 > 0:08:24That's Nothronychus,
0:08:24 > 0:08:27a vegetarian dinosaur whose carnivore ancestry
0:08:27 > 0:08:30meant it could handle itself in a fight.
0:08:32 > 0:08:34For size, this was a pretty big dinosaur,
0:08:34 > 0:08:37nearly a tonne in weight and five metres long.
0:08:39 > 0:08:41Tools? It had those very handy claws.
0:08:41 > 0:08:46Great for grabbing leaves, and very effective weapons for defence.
0:08:46 > 0:08:48And weirdness?
0:08:48 > 0:08:52A really strange fella who gave up meat to eat huge amounts of veg,
0:08:52 > 0:08:55giving itself a pot-belly in the process.
0:08:57 > 0:09:01But weird dinosaurs come in all kinds of shapes and sizes,
0:09:01 > 0:09:04from the very big to the very small.
0:09:09 > 0:09:10Meet Epidexipteryx,
0:09:10 > 0:09:14a very strange-looking, pigeon-sized creature
0:09:14 > 0:09:17that you would have found in lush forests like this,
0:09:17 > 0:09:20154 million years ago.
0:09:24 > 0:09:26This dinosaur lived in Asia.
0:09:26 > 0:09:28It was small,
0:09:28 > 0:09:32only half a metre long from its head to the tip of its tail.
0:09:33 > 0:09:37And it had a bird-like skeleton, covered in feathers.
0:09:42 > 0:09:46Epidexipteryx was a dinosaur like no other.
0:09:46 > 0:09:49Everything about this creature is weird.
0:09:49 > 0:09:51Its tongue-twisting name,
0:09:51 > 0:09:55its gangly arms and odd, sticky-out teeth.
0:09:55 > 0:09:58Here it's looking for food inside this log,
0:09:58 > 0:09:59but if it's not careful,
0:09:59 > 0:10:03it could turn into someone else's dinner,
0:10:03 > 0:10:08because on its trail is a big, hungry carnivore called Sinraptor.
0:10:16 > 0:10:20Being small, though, means Epidex can escape those vicious jaws
0:10:20 > 0:10:21inside this hollowed-out log...
0:10:24 > 0:10:25But not for long...
0:10:33 > 0:10:37He makes a break for the trees and just manages to get away.
0:10:38 > 0:10:42Epidex's weird fingers come to the rescue.
0:10:44 > 0:10:48Those fingers, though, are for more than just climbing trees.
0:10:48 > 0:10:49Watch this.
0:10:51 > 0:10:55That third finger on both its clawed hands
0:10:55 > 0:10:57is much longer than all the others.
0:10:57 > 0:11:01It's a tool Epidex uses in a very clever way,
0:11:01 > 0:11:05for getting at food hidden inside the tree...
0:11:07 > 0:11:10It taps on the trunk and listens for the sounds of insects.
0:11:10 > 0:11:11If there's food in there,
0:11:11 > 0:11:15it will use that very long finger to get at what's inside...
0:11:23 > 0:11:26Amazingly, there is actually an animal today
0:11:26 > 0:11:30that uses the very same weird method for getting its dinner.
0:11:30 > 0:11:32This is an aye-aye.
0:11:32 > 0:11:33It's a small mammal
0:11:33 > 0:11:36that lives in Madagascar off the coast of Africa.
0:11:40 > 0:11:44Just like Epidex, it has a very long third finger.
0:11:44 > 0:11:46It taps on the tree and listens.
0:11:48 > 0:11:52When it hears something inside, it scrapes away at the bark,
0:11:52 > 0:11:55hoping to get some juicy insects to eat.
0:11:59 > 0:12:02Rewind 154 million years,
0:12:02 > 0:12:04our Epidexipteryx has struck gold...
0:12:04 > 0:12:09It's after a big, juicy beetle grub.
0:12:17 > 0:12:19Outside the dinosaur workshop,
0:12:19 > 0:12:22I'm turning myself into a very strange creature.
0:12:30 > 0:12:32Epidexipteryx had probably
0:12:32 > 0:12:35the weirdest set of hands I've ever seen.
0:12:35 > 0:12:37They kind of had these two shorter talons
0:12:37 > 0:12:40and then this one ludicrously long finger.
0:12:40 > 0:12:44Its way of life was to climb trees and eat grubs.
0:12:44 > 0:12:45Now what I want to do
0:12:45 > 0:12:48is get an idea of what that would have been like
0:12:48 > 0:12:52and the strengths and weaknesses of the features it had evolved.
0:12:52 > 0:12:56So I'm going to set off as a normal person
0:12:56 > 0:12:58to live the life of an Epidexipteryx.
0:12:58 > 0:13:00Got myself a jungle here.
0:13:00 > 0:13:02Hopefully there's some food in there somewhere.
0:13:02 > 0:13:04I'm going to see if I can find it.
0:13:05 > 0:13:10When it comes to climbing, our hands are actually pretty good.
0:13:10 > 0:13:12We've got sort of short, stubby, strong fingers
0:13:12 > 0:13:13that can grip
0:13:13 > 0:13:18and move our way up through the trees pretty effectively.
0:13:18 > 0:13:19But what about foraging for food?
0:13:19 > 0:13:22Now if I wanted to find maybe a big fat tasty grub to eat,
0:13:22 > 0:13:24what are my hands like then?
0:13:26 > 0:13:31A-ha! In here I see some food. There's a little grub in this log.
0:13:33 > 0:13:35The problem is,
0:13:35 > 0:13:38our strong stubby fingers haven't got the length
0:13:38 > 0:13:40to get into little nooks and crannies
0:13:40 > 0:13:42to pull grubs out.
0:13:42 > 0:13:44What I need is a new set of hands.
0:13:46 > 0:13:48On with my Epidexipteryx gloves.
0:13:52 > 0:13:54What I find,
0:13:54 > 0:13:57climbing as an Epidexipteryx...
0:13:58 > 0:14:01..I've got to climb in a different way.
0:14:01 > 0:14:03Because I've only got three fingers,
0:14:03 > 0:14:04I've got to use my feet more.
0:14:04 > 0:14:08Cos, even with my fingers, only two of them are any good for gripping.
0:14:08 > 0:14:12This third one feels like a positive disadvantage on the climbing front.
0:14:12 > 0:14:13But I'm getting used to it.
0:14:13 > 0:14:16Now, let me get up here, towards where the food is.
0:14:20 > 0:14:24Now... Now I can see this big fella coming into its own!
0:14:24 > 0:14:29Cos that little nest of grubs are now all within reach.
0:14:30 > 0:14:31Oh, got it!
0:14:31 > 0:14:34Come on!
0:14:34 > 0:14:35Look at that!
0:14:35 > 0:14:40Now I really am beginning to enjoy life as an Epidexipteryx!
0:14:44 > 0:14:49There are so many strange things about Epidexipteryx, aren't there?
0:14:49 > 0:14:54I mean, how can we be sure that a dinosaur like this really existed?
0:14:54 > 0:14:57By taking a look at the evidence - that's how.
0:14:59 > 0:15:03This extraordinary fossil was discovered recently in China.
0:15:03 > 0:15:07It shows a whole Epidexipteryx.
0:15:07 > 0:15:09Its bird-like appearance is clear,
0:15:09 > 0:15:12as are its odd-looking teeth on its skull.
0:15:12 > 0:15:16You can even see the long tail feathers.
0:15:19 > 0:15:21Epidexipteryx was about the size of a pigeon.
0:15:23 > 0:15:25But a pigeon's feathers help it to fly.
0:15:30 > 0:15:34The feathers on this dinosaur were for display.
0:15:34 > 0:15:36In other words, showing off.
0:15:41 > 0:15:43And that's the funny thing about Epidexipteryx -
0:15:43 > 0:15:45it had feathers,
0:15:45 > 0:15:46it looked like a bird,
0:15:46 > 0:15:47but it couldn't fly.
0:15:51 > 0:15:54And that means that when it drops this beetle...
0:15:54 > 0:15:56EPIDEXIPTERYX MOANS
0:15:57 > 0:16:01..and goes down onto the forest floor to get it back,
0:16:01 > 0:16:02it's vulnerable.
0:16:09 > 0:16:12Should have stayed up in the trees
0:16:12 > 0:16:13where it was safe.
0:16:17 > 0:16:18So that's Epidexipteryx.
0:16:18 > 0:16:21A tree-climbing, bird-like creature
0:16:21 > 0:16:23with a special way of getting food.
0:16:24 > 0:16:27For size, this was a very small dinosaur,
0:16:27 > 0:16:29a featherweight 200 grams,
0:16:29 > 0:16:31and just half a metre long.
0:16:31 > 0:16:33Tools?
0:16:33 > 0:16:35It has to be that amazing long finger
0:16:35 > 0:16:39for getting insects inside tree trunks.
0:16:39 > 0:16:40And Weirdness?
0:16:40 > 0:16:42Funny teeth, strange claws,
0:16:42 > 0:16:44and feathers but no wings.
0:16:44 > 0:16:46Basically, everything.
0:16:47 > 0:16:51Both Epidexipteryx and Nothronychus
0:16:51 > 0:16:53were pretty weird dinosaurs.
0:16:53 > 0:16:57But here's one to match them for strangeness.
0:16:57 > 0:16:59And beat them for deadliness.
0:16:59 > 0:17:02Meet Gigantoraptor.
0:17:07 > 0:17:08A breathtaking creature,
0:17:08 > 0:17:11with a body like a huge, overgrown ostrich
0:17:11 > 0:17:16and a head with a fearsome, parrot-like beak...
0:17:16 > 0:17:19It's the largest feathered animal ever discovered.
0:17:21 > 0:17:24Gigantoraptor was one and half tonnes in weight
0:17:24 > 0:17:26and a massive eight metres long.
0:17:26 > 0:17:30It had vicious dagger-like claws
0:17:30 > 0:17:33and lived 80 million years ago.
0:17:40 > 0:17:42Gigantoraptors were to be found in Asia,
0:17:42 > 0:17:46roughly where you'd find Mongolia today.
0:17:46 > 0:17:51They come from a family of dinosaurs known as Oviraptorids,
0:17:51 > 0:17:53but Gigantoraptor was by far and away
0:17:53 > 0:17:56the biggest member of this strange family.
0:17:56 > 0:18:01How do we know such an odd creature ever existed?
0:18:01 > 0:18:05By taking a look at the evidence - that's how.
0:18:08 > 0:18:11This is the Gobi Desert in Mongolia, Asia.
0:18:11 > 0:18:17In 2007, the bones of a Gigantoraptor were discovered here.
0:18:17 > 0:18:18They were huge -
0:18:18 > 0:18:2335 times bigger than any other of its close relatives.
0:18:25 > 0:18:28It's their sheer size that's incredible.
0:18:29 > 0:18:32It looks a bit like an ostrich.
0:18:32 > 0:18:37But it would need four ostriches standing on top of each other
0:18:37 > 0:18:40to match the height of a Gigantoraptor.
0:18:46 > 0:18:49We know that Gigantoraptors had feathers
0:18:49 > 0:18:51because they've been found on the fossils
0:18:51 > 0:18:53of other closely related dinosaurs.
0:18:53 > 0:18:56But Gigantoraptor's feathers weren't for flying,
0:18:56 > 0:18:59nor were they for keeping warm...
0:18:59 > 0:19:02These were feathers for display,
0:19:02 > 0:19:05especially for attracting a mate.
0:19:05 > 0:19:09Here, a male and female Gigantoraptor
0:19:09 > 0:19:11are doing a kind of dance.
0:19:19 > 0:19:22It's a bit like showing off your best dance moves
0:19:22 > 0:19:24at the school disco.
0:19:27 > 0:19:31Now, if that sounds just too far-fetched,
0:19:31 > 0:19:32take a look at these grebes.
0:19:35 > 0:19:36Just like the Gigantoraptors,
0:19:36 > 0:19:40they're carrying out what's called a courtship dance.
0:19:40 > 0:19:44They move in time, display their feathers,
0:19:44 > 0:19:46and copy each other's movements.
0:19:46 > 0:19:49The aim is to find and hopefully attract a mate.
0:19:52 > 0:19:56Gigantoraptor's similarity to birds really stands out.
0:19:56 > 0:20:01But there's more to this resemblance than feathers and beaks.
0:20:03 > 0:20:06That's because they laid eggs.
0:20:06 > 0:20:08However big or small,
0:20:08 > 0:20:09this is how dinosaurs gave birth.
0:20:13 > 0:20:15Even Argentinosaurus,
0:20:15 > 0:20:20the most massive dinosaur of all, laid eggs.
0:20:21 > 0:20:24But what's special about Gigantoraptor
0:20:24 > 0:20:26is the way it nested.
0:20:26 > 0:20:28It stayed with its eggs, protecting them,
0:20:28 > 0:20:30just like lots of birds do.
0:20:31 > 0:20:32It's called brooding.
0:20:32 > 0:20:35The idea is, that by looking after their eggs this way,
0:20:35 > 0:20:38there's more chance of them hatching successfully.
0:20:44 > 0:20:47Meanwhile, in the dinosaur workshop,
0:20:47 > 0:20:50I'm HATCHING a very EGG-CITING plan!
0:20:50 > 0:20:52Yeah, erm...sorry.
0:20:52 > 0:20:56There is one thing that all dinosaurs have in common -
0:20:56 > 0:20:57they lay eggs.
0:20:57 > 0:20:59And in the case of the Gigantoraptor,
0:20:59 > 0:21:02eggs like I have never seen before.
0:21:02 > 0:21:04To show you how odd they are,
0:21:04 > 0:21:06let's first look at more familiar eggs.
0:21:06 > 0:21:09That is a chicken's egg. We all know what these are like,
0:21:09 > 0:21:12they're three centimetres long, we have 'em for breakfast.
0:21:12 > 0:21:15This is an ostrich egg.
0:21:15 > 0:21:20Now, this is the biggest egg that's laid on the planet in modern times.
0:21:20 > 0:21:22It's a pretty good size
0:21:22 > 0:21:25and it comes from a pretty good-sized bird.
0:21:25 > 0:21:28And this is a genuine dinosaur egg,
0:21:28 > 0:21:30or at least a fossil of one.
0:21:30 > 0:21:32This would have been laid in muddy ground
0:21:32 > 0:21:34about 70 million years ago.
0:21:34 > 0:21:39And over that time, the mud has turned into rock
0:21:39 > 0:21:41and the egg has turned into a fossil.
0:21:41 > 0:21:43And this is our Gigantoraptor egg.
0:21:43 > 0:21:46I say ours, because we've made it.
0:21:46 > 0:21:48But we've made it very carefully
0:21:48 > 0:21:51to be the right size, shape, and strength
0:21:51 > 0:21:55to match fossilized Gigantoraptor eggs that were recently found.
0:21:55 > 0:21:59These eggs took about 80 days to hatch.
0:21:59 > 0:22:03Now, that is a long time for it to be exposed to potential predators.
0:22:03 > 0:22:07So they would have to have been made pretty strong.
0:22:07 > 0:22:09How strong? Let's find out.
0:22:11 > 0:22:14Naturally, my fellow dino engineers, Andy and Jim,
0:22:14 > 0:22:18are filling my Gigantoraptor egg with white and yolk.
0:22:20 > 0:22:22This is my egg strength testing machine.
0:22:24 > 0:22:25Gigantoraptor egg is up there.
0:22:25 > 0:22:28Whatever weight gets loaded on here,
0:22:28 > 0:22:30gets felt by the egg up there.
0:22:30 > 0:22:35When this weight here gets too much for that egg...
0:22:35 > 0:22:39First - these bags weigh 25 kilos.
0:22:41 > 0:22:43And the egg doesn't seem to care about that.
0:22:43 > 0:22:46Looks like I might have to get involved here.
0:22:46 > 0:22:48Not in my best t-shirt.
0:22:52 > 0:22:53I'm 75 kilos.
0:22:57 > 0:22:59100 kilos on our Gigantoraptor egg.
0:23:01 > 0:23:03More weight.
0:23:08 > 0:23:11That's 125 kilos.
0:23:11 > 0:23:14Now, dinosaur experts did reckon that these eggs
0:23:14 > 0:23:16would probably have taken that,
0:23:16 > 0:23:20but they weren't sat underneath the egg at the time. More weight.
0:23:20 > 0:23:22'This Gigantoraptor egg
0:23:22 > 0:23:25'is living up to its tough reputation.'
0:23:29 > 0:23:31That's 150 kilos.
0:23:37 > 0:23:39GIGGLING
0:23:40 > 0:23:42Aaaah!
0:23:47 > 0:23:50Right, well, that's a nice piece of science
0:23:50 > 0:23:53because that egg pretty much fitted
0:23:53 > 0:23:55with what dinosaur experts reckoned
0:23:55 > 0:23:58the Gigantoraptor egg would have taken...
0:24:04 > 0:24:07Rewind 80 million years to Mongolia.
0:24:07 > 0:24:11Our Gigantoraptor's nest is in great danger.
0:24:13 > 0:24:15Two hunting Alectrosaurs.
0:24:15 > 0:24:18These five-metre long carnivores are hungry
0:24:18 > 0:24:21and those eggs would be a tasty treat...
0:24:21 > 0:24:25if they can get past this mother Gigantoraptor.
0:24:28 > 0:24:31She may be outnumbered, but when her nest is threatened
0:24:31 > 0:24:34- she's a fearsome opponent. - GIGANTORAPTOR ROARS
0:24:41 > 0:24:44But while she's fighting off the Alectrosaurs,
0:24:44 > 0:24:48another nest raider, an Oviraptor, has its eyes on her eggs.
0:24:58 > 0:25:01Our Gigantoraptor gets back in the nick of time.
0:25:04 > 0:25:06So that's Gigantoraptor,
0:25:06 > 0:25:09an extraordinary creature.
0:25:09 > 0:25:12A dinosaur that was a kind of huge flightless bird.
0:25:12 > 0:25:15It would do anything to protect its young.
0:25:15 > 0:25:19How does it match up with my other weird dinos?
0:25:21 > 0:25:25There was the very strange Nothronychus.
0:25:28 > 0:25:30For size, a pretty big dinosaur,
0:25:30 > 0:25:35nearly one tonne in weight and five metres long.
0:25:35 > 0:25:36Tools?
0:25:36 > 0:25:38Remember those very handy claws.
0:25:38 > 0:25:41Great for grabbing leaves and deadly in defence.
0:25:42 > 0:25:43And weirdness?
0:25:43 > 0:25:46Well, this was a very odd beast.
0:25:46 > 0:25:50A carnivore turned herbivore, with that huge pot-belly.
0:25:51 > 0:25:54And then the truly bizarre Epidexipteryx.
0:25:56 > 0:25:59Size-wise, a very small dinosaur,
0:25:59 > 0:26:01a featherweight 200 grams
0:26:01 > 0:26:03and just half a metre long.
0:26:03 > 0:26:04Its tools?
0:26:04 > 0:26:07It has to be that extraordinary long finger
0:26:07 > 0:26:09for getting insects inside trees.
0:26:09 > 0:26:12And weirdness?
0:26:12 > 0:26:13It was off the scale.
0:26:13 > 0:26:16Funny teeth, strange claws,
0:26:16 > 0:26:18and feathers but no wings.
0:26:18 > 0:26:19Just about everything.
0:26:20 > 0:26:25Finally, the outsized, outlandish Gigantoraptor.
0:26:25 > 0:26:26Size?
0:26:26 > 0:26:28A massive one and a half tonnes
0:26:28 > 0:26:30and a towering eight metres.
0:26:30 > 0:26:34For tools, it had those terrific defensive claws
0:26:34 > 0:26:37and a big, parrot-like beak.
0:26:38 > 0:26:39Weirdness?
0:26:39 > 0:26:41Well, there was the courtship dancing
0:26:41 > 0:26:44and those weird wings that couldn't fly.
0:26:45 > 0:26:48This one is just too close to call.
0:26:48 > 0:26:52All these creatures are equally weird.
0:26:54 > 0:26:57So I'm going for my favourite, that tiny dinosaur
0:26:57 > 0:27:01with strange big eyes and long spindly fingers -
0:27:01 > 0:27:03Epidexipteryx.
0:27:09 > 0:27:10In the end though,
0:27:10 > 0:27:14Epidexipteryx, like nearly all the dinosaurs, was doomed.
0:27:17 > 0:27:18Whether big or small,
0:27:18 > 0:27:21they were wiped out when a huge asteroid,
0:27:21 > 0:27:24nearly ten miles wide,
0:27:24 > 0:27:26struck our planet 65 million years ago.
0:27:31 > 0:27:36But, in a way, that isn't the end of dinosaurs on Earth.
0:27:39 > 0:27:45Because their descendants, birds, are with us everywhere today.
0:27:45 > 0:27:49So next time you see one in your garden,
0:27:49 > 0:27:52remember where it came from.
0:27:55 > 0:27:58Subtitles by Red Bee Media Ltd
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