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00:16Over 66 million years ago our world was ruled.
00:30By dinosaurs.
00:38The largest animals that have ever walked the earth.
00:49Today dinosaur experts across the globe are uncovering the bones they left behind.
01:00Allowing us to imagine how these extraordinary creatures may have lived.
01:10So that we can tell their stories.
01:16And they can walk again.
01:50And they can walk again.
01:55Utah, in the heart of the American West.
02:03Home to some of the most spectacular scenery on earth.
02:21And the forces that shaped the landscape also make it a paradise for dinosaur hunters.
02:41In a remote part of the desert, paleontologists Dr. Jim Kirkland and Dr. Josh Lively have made a remarkable discovery.
02:53So we've exposed quite a bit of bones, Jim.
02:55Yeah, that would be great.
03:01The bones of one of the most heavily armored dinosaurs that ever lived.
03:11Oh, that's cool.
03:13A Gastonian.
03:15Yeah, he might have a leg, isn't it?
03:18Using their discoveries, we can imagine how this youngster lived and died.
03:27One hundred and thirty million years ago.
03:48In the early Cretaceous period, the land that will become Utah was warmer and warmer.
04:00And wetter.
04:09And what is desert today is covered by conifer forests and rolling meadows of ferns.
04:34Plentiful food for groups of plant-eating Gastonia, including youngster George.
04:57Like all young Gastonia, he must stick close to his parents.
05:11Because danger is never far away.
05:28Utahraptor.
05:29Utahraptor.
05:33A heavyweight cousin of Velociraptor, the size of a grizzly bear.
05:44and they hunt vulnerable young Gastonia
05:54the ferns providing ideal cover for a surprise attack
06:09just yards away George and his family are oblivious to the approaching danger
06:43with the Raptors within striking distance the Gastonia get a lucky break
07:05like many modern herd animals the adults form a
07:09defensive ring around their young weighing over a time covered in thick
07:21armor a group of adult Gastonia is virtually invulnerable
07:51with one of their group injured the Raptors cut their losses
08:06but George can't rely on the safety of the herd for much longer he's reached
08:13adolescence when like all young male Gastonia it's thought he'll be pushed out of the group
08:28George must now grow up without his family to protect him
08:40we'll probably do Dakota and at least one other person too at the dig the team is
08:47starting to uncover evidence there's a bone there coming up from somewhere get your
08:54fingers under that reach over that might explain how young Gastonia like George
09:00survived to adulthood you got one over there okay it's like a limb bone might connect to some of this
09:09bone right here and the clues are coming thick and fast beautiful that's bone that's like the
09:16red might go into this one everywhere they dig bone after bone emerges from the ground
09:28found a couple of ribs right here going over top of a vertebra and then several pieces of armor a
09:36ton
09:36of bones just in this small spot it's too many to be from just one individual then rib like sections
09:46right I mean so far you know right in here that right parts of two animals and intriguingly all the
09:55Gastonia found across the site appear to be of a similar age from looking at skeletal remains we're
10:04looking at half-grown individuals sub-adults to full adults kind of analogous to teenagers right yeah
10:14all these teenagers found together suggests something unexpected
10:43since leaving his family group George has been living on his own
10:54keeping deep in the forest where it's easier to hide from predators
11:16but it's not long before he comes face to face with another young male
11:32and it looks like he means business
12:05gastonia's skulls and necks
12:07especially adapted to act like shock absorbers
12:18but this isn't a fight
12:29this is how Gastonia make friends
12:39of all the armored dinosaurs
12:44they're one of the only known social species
12:51George has just joined a group
13:02it's a huge step forward dramatically increasing his chances of making it to adulthood
13:17this gang of teenage boys will stay together until they're tough enough to fend for themselves
13:31because until their armor is fully developed they're vulnerable
13:47just working our way around these elements trying to get around this big femur here
13:53at the dig amongst the Gastonia bones
13:56hey Josh check this out what is that
13:59the team makes an unexpected discovery
14:02oh wow
14:04that's really neat
14:05it's definitely not Gastonia
14:10probably somewhat
14:12hey Jim
14:14yeah
14:16Heather found something interesting
14:18and I'm wondering if you could tell me whether or not it is what I think it is
14:24that's a small theropod metacarpal and bone could be a juvenile Utahraptor
14:41Utahraptor bones found alongside the young Gastonia
14:51suggest that throughout the Gastonia's adolescence Utahraptor was an ever-present threat
15:08and Josh and Jim have evidence that shows just how deadly they could be
15:17a cast of a Utahraptor toe-claw
15:20you know you put the claw itself you know this is the bone underlying it
15:27just to be conservative we could say it comes out to about there
15:30you know in length
15:3330 centimeters long
15:34these killing claws were Utahraptor's primary weapon
15:41this thing might be kicking through inch thick hide so fast you can barely see it
15:46wham wham wham wham
15:48this thing's just punching lots of holes which would do a lot of damage
15:52these claws are the perfect tool for puncturing the weak armor of young Gastonia
15:59maybe you have to think of it more as a can opener
16:02yeah if you can flip it over
16:04use that to slice open the belly
16:07yeah these things are one of the most formidable predators that ever lived
16:23holding their toe claws off the ground to keep them razor sharp
16:34Utahraptor
16:37is a finely tuned killing machine
16:47and this adult male
16:52and the group he leads
16:55have just entered the forest
17:00following the trail of George
17:03and the Gastonia gang
17:15but hidden beneath the thick undergrowth
17:22finding them
17:23won't be easy
17:33so the young raptors
17:35streak ahead
17:39to try and flush them out
17:47while the adults
17:49follow behind
17:50ready to make the kill
18:08with Utahraptor's eyesight
18:10as sharp as modern birds of prey
18:15even the slightest movement
18:18could be fatal
18:29so when they hear the raptors coming
18:34the Gastonia
18:36freeze
19:01the juveniles have missed them
19:08but George must hold his nerve
19:11because the deadliest threat
19:13is still to come
19:22the group leader
19:27the
19:39Oh, my God.
20:05It's a close call.
20:21But every day George and the gang survive is a day closer to the safety of adulthood.
20:36And emerging from the ground, clues that reveal even young Gastonia would have been no pushover.
20:49Well, you should be getting close, I think.
20:52Hey, Josh.
20:54Look at my section.
20:55Tell me what you think.
20:58So...
21:01There's so much here.
21:04There are plenty of osteoderms.
21:06And they're coming out pretty solid then?
21:08Yeah.
21:11Osteoderms are the bones that made up the Gastonia's armor.
21:16That's a real nice one.
21:17Oh, yeah.
21:18So you can kind of see on this one that kind of ridge right there, that keel, that would point
21:24up.
21:24Makes for a spiky dinosaur.
21:26It really does, yeah.
21:30In life, each osteoderm was covered by a thick scale.
21:35Now, this is one of the nicest ones we've had so far.
21:39This would have been on the back of the animal.
21:42Which would have created an armored plate.
21:47You see the hollow base that these have.
21:49They're for blood vessels bringing nutrients up into this bone to grow that big scale that was on top.
21:57There's a lot of armor on these animals.
22:03It's a discovery that reveals the Gastonia's armor was nearly fully formed.
22:25But the team has evidence.
22:28Utahraptor was one step ahead.
22:38Revealed by an astonishing fossil found near the site.
22:42And taken to the lab for analysis.
22:46It's a gold mine.
22:48It really is.
22:52Entombed in this nine-ton block of sandstone.
22:56The team has discovered the remains of an entire group of Utahraptors.
23:02And over here we've got a big string of articulated vertebra.
23:08Yeah, and that's just beautiful.
23:10And hidden amongst the hundreds of perfectly preserved teeth and claws and bones.
23:17Yeah, that's the great thing about this block. We'll have so much material.
23:20Curator Don DeBloom has found something that could be Utahraptor's deadliest weapon.
23:28We've got this beautiful little top of a skull.
23:31And then we flipped it over.
23:36Right here is the impression of the brain.
23:39For a dinosaur, this young Utahraptor brain is very large.
23:45Yeah, certainly remarkable given the size.
23:49You know, that would be a very intelligent animal.
23:51It would have been the most intelligent animal of its time.
23:55Oh, certainly.
23:57Utahraptor.
23:57It would have been capable of some pretty complex behaviors.
24:14Spring has turned to summer.
24:27And as the dry season sets in, George and the Gastonia gang leave the forest to find water.
24:45They're still unruly teenagers.
24:53But now, in near adult bodies.
25:09And at the edge of the water hole, clay-rich soil provides the gang with essential minerals.
25:20Vital for strengthening their armor.
25:30And now the Gastonia are tougher.
25:33They're no longer an easy kill.
25:40So the raptors change tactics.
25:47The group leader attracts their attention.
25:57And uses his brightly colored wing feathers.
26:05To create.
26:08A diversion.
26:29Like a fox in a hen house.
26:33The kill triggers the leader's predatory instinct.
26:49Trapped at the water's edge.
26:53It looks like George's luck.
26:57Has run out.
27:13But at the dig, Josh and the team have made a discovery.
27:23They've come to retrieve a fossil that may shed light on events that happened here.
27:29130 million years ago.
27:33So Don, I was originally thinking it was down this drainage.
27:36But looking at it now, I actually think it's further over that way.
27:39Yeah, I think you're right.
27:40But collecting it from the steep cliff face.
27:44Damn, this is going to be tough.
27:47Won't be easy.
27:51It might be farther that way.
27:58Oh, there it is.
27:59Yeah.
28:01That's totally it.
28:03Yeah.
28:04So Don, I think if you want to bring the backboard over here, and then we can go ahead and
28:09start strapping it down.
28:12With your legs.
28:13Keep that.
28:13Do it.
28:15This is a fossilized foot cast.
28:18Oh man, on campus.
28:20Alright.
28:20Alright, you got it, Marcella.
28:22Got it.
28:27It formed when a dinosaur footprint filled with silt and dust, that over millions of years was compressed into solid
28:36rock.
28:38Like that?
28:39Okay.
28:39Just like that.
28:41Like a ledge.
28:42Not super fragile.
28:45Creating a cast of the foot that made it.
28:53One, two, three.
28:54It definitely gets easier up here.
29:00But which dinosaur does it belong to?
29:10Yeah.
29:12That's really cool.
29:13We've got three big wide toes on this footprint.
29:17So that eliminates a couple of dinosaurs right off the bat.
29:20Yeah.
29:21If it was Gastonia, it'd have four toes.
29:26And it's unlikely to be a predator, because there are no claws.
29:31Most likely a plant eater.
29:33Yeah, I think a good candidate could be some sort of bipedal, plant-eating dinosaur, kind of like Planicoxa.
29:40Right. We're at the right level for those guys.
29:42They're close.
29:42Absolutely.
29:46Planicoxa were beaked, stocky dinosaurs that lived in herds.
29:51You can imagine them traveling together and moving long distances.
29:55For sure.
29:55Maybe Gastonia was year-round and these dinosaurs were more seasonal.
30:03All right.
30:05You guide us, Steph.
30:07Finding Planicoxa footprints here is an important discovery.
30:15Because it suggests they migrated through this landscape.
30:20Of course they were able to walk to a족 here.
30:23They survived, they were blown away.
30:30For sure.
30:39They didn't do all of a sudden células are more pleasing.
30:39Thank you very much.
30:39Thank you very much.
30:40Thank you very much.
30:47And we're going to have a new host and a new host.
30:47As the group leader closes in,
30:49on George. A herd of planicoxa pass close by. And without any armour, they're a much easier
31:10to kill. Handing George. A very lucky escape.
31:40But as the dry season intensifies, the planicoxa herds will move on. So, as George and the Gastonia
31:53gang return to the forest, they know it won't be long until the raptors are hunting them
31:59down once more.
32:15But coming out of the ground...
32:17Let's see how long this is. Further evidence, the Gastonia buried here...
32:22We're looking at about 31 and a half centimetres long.
32:26...were more than capable of defending themselves.
32:29...proximal width, where it attaches to the tail, looks like about 17 and a half centimetres
32:36wide.
32:37Yeah.
32:37So, yeah, this is one of these specialised spikes along the tail.
32:43Like, sticking out?
32:44Yeah, yeah, so it'll be sticking out from the sides of the tail. You can imagine this with
32:51a big scale over top of it, a big piece of keratin. So this would have come to a very
32:55sharp
32:56point. And these, we think, were used as a weapon.
33:03These blade-like spikes were positioned along the entire length of the Gastonia's tails.
33:17And Jim and Don have uncovered something that shows just how these weapons were used.
33:23...diving down, and then as I was trying to work on that, I hit something over here.
33:29So this is a femur, the upper leg bone.
33:32And that's a pretty sizable femur.
33:34And then as I dug around, I see we have a complete tibia, lower leg bone.
33:39Yeah. You can see how short, you know, the lower leg is, rather than the upper leg.
33:44About half the length.
33:46Right there.
33:47Which is, you know, the exact opposite than what you see in a running animal.
33:54Gastonia had a top speed of around five miles per hour.
34:00Because their hind legs weren't built for running.
34:05They were adapted for a very different purpose.
34:10Certainly, these things are not just simple bones.
34:13They have huge muscle attachment points.
34:15So they've developed powerful legs for serious, strong maneuverability.
34:20Stocky guys just standing their ground.
34:23You just see these things just holding on the ground,
34:26and swinging their tail with those big blades.
34:30It's like the one over there they already pulled out.
34:32Yeah, that big boy.
34:33You know, slashing across.
34:35And probably reach head high easily.
34:38And literally slap a Utahraptor, you know, right in the face.
34:46Gastonia's powerful hind legs and spiked tails
34:54mean George and the gang are now formidable adversaries.
35:09But with the dry season now at its height,
35:11and the planicox are gone.
35:17The raptors are starving.
35:27Desperate for food, they must take any opportunity.
35:36To make a kill.
35:49But now nearly fully grown,
35:52the Gastonia gang will stand and fight.
36:12And this time,
36:14they've got the weapons to defend themselves.
36:31The Gastonia now have the upper hand.
36:39But driven by hunger,
36:41the raptors have no choice but to attack.
37:08With the group leader fatally wounded,
37:15the remaining raptors back down.
37:27But George's moment of triumph will be short-lived.
37:39The hot summer months bring a new danger.
37:51Something revealed by a completely different type of evidence.
37:57found alongside the Gastonia bones.
38:00Found alongside the Gastonia bones.
38:08Paleo botanist Dr. Carol Hotton
38:11is an expert in ancient pollen.
38:22Okay, Carol.
38:24Hey Jim, take a look.
38:25There's some interesting grains right in the center.
38:29So, if you see those little round grains
38:32that look like flat tires,
38:35that's pollen from an extinct conifer.
38:41And there's another grain.
38:46That's a member of the Cypress family
38:49that was well adapted to dry conditions.
38:57All the pollen Carol has identified
38:59belongs to trees that lived in a parched, arid environment.
39:09One hundred and thirty million years ago,
39:12the forest that covered the dig site was a tinder box.
39:20You can see all through the field black pieces.
39:24Yeah, little shards.
39:26Yeah, little shards.
39:27Yeah, little shards.
39:28Twiggy-looking things.
39:29Yeah, right.
39:29Except for baseball for twigs.
39:30Right.
39:31In all probability, they represent charcoal.
39:35It's unlikely to be anything else,
39:37and I see that in all my pollen samples.
39:43There's only one thing that could have produced so much charcoal.
39:59The long, dry summer months have created a time bomb.
40:10As wildfire rages through the parched forest,
40:19it threatens the Gastonia and the surviving raptors.
40:46But George is slow to react to the danger.
41:13With a top speed around 20 miles per hour,
41:17the raptors soon reach a clearing in the forest.
41:30But they're trapped between the flames and a treacherous marshy swamp.
41:43And George and the Gastonia gang aren't far behind.
41:56The flames driving the two mortal enemies together.
42:04For one final showdown.
42:24But back at the land.
42:27The sandstone block filled with raptor bones has one last secret to reveal.
42:37Nice little jaw right there.
42:40Oh, yeah, I see the teeth on that.
42:43Amazing thing is that all these delicate little teeth are all still in place in their sockets.
42:47It's really remarkable to have it so well preserved.
42:51Such high levels of preservation.
42:54And certainly this, you know, still has the teeth included.
42:59Tell the team the bones have not been disturbed.
43:03The block captures the very moment the raptors died.
43:09And it's interesting that all the best preserved bones all seem to be in this sand.
43:15Yeah, I suggest that sand is part of why they died, why they're so well preserved.
43:23Although the sand is solid today, Jim believes that when the raptors died, it was liquid.
43:32You know, what killed them is what buried them, given the geology of the setting.
43:38Most likely, we're looking at a mass mortality tied to quicksand.
43:42Bullsand.
43:57Laugh and Corbett
44:24Panicked, the raptors run into trouble.
44:56With the raptors out of the way,
44:59George has the chance to escape.
45:26But they're struggling.
45:31The very things that protected them from the raptors, heavy armor and short stocky legs, mean
45:49George and the gang are too slow to escape the fire.
46:09One by one.
46:13The smoke takes its toll.
46:30Buried where they fell.
46:34The landscape is transformed around them.
46:45Layer upon layer of rock builds up as the eons pass and the continents silently drift across
46:57the face of the earth.
47:05Until George and the gang are finally found.
47:10One hundred and thirty million years later.
47:31Next time, T-Rex's lethal, faster cousin.
47:41A young hunter, fighting for her place in the most ferocious pack on earth.
47:50The first time around the sky.
47:57What can you do?
48:18The first time coming spirit.
48:18You