0:00:05 > 0:00:06We are living through
0:00:06 > 0:00:08THE golden age
0:00:08 > 0:00:10of dinosaur discoveries.
0:00:10 > 0:00:12From all over the world,
0:00:12 > 0:00:15a whole new generation of dinosaurs has been revealed.
0:00:15 > 0:00:17From the biggest giants...
0:00:19 > 0:00:21..and the deadliest killers,
0:00:21 > 0:00:23to the weird and wonderful.
0:00:31 > 0:00:33From the Arctic
0:00:33 > 0:00:35to Africa.
0:00:35 > 0:00:38From South America to Asia.
0:00:38 > 0:00:41Using the latest evidence,
0:00:41 > 0:00:43for the first time
0:00:43 > 0:00:47we have a truly global view of these incredible animals.
0:01:03 > 0:01:05This time,
0:01:05 > 0:01:08we journey back 150 million years
0:01:08 > 0:01:10to the Jurassic Period.
0:01:10 > 0:01:13A time when the first giant killers stalked the earth.
0:01:16 > 0:01:18But these giants weren't confined to the land.
0:01:18 > 0:01:20Recent discoveries
0:01:20 > 0:01:23have revealed an astonishing new hunter in the oceans.
0:01:29 > 0:01:34These new giant killers posed the greatest of threats.
0:01:34 > 0:01:39With the smallest advantage tipping the balance between life and death,
0:01:39 > 0:01:44predator and prey were locked in a perpetual battle for survival.
0:01:45 > 0:01:47DINOSAUR ROARS
0:01:51 > 0:01:53To understand this world,
0:01:53 > 0:01:57we must travel back 150 million years
0:01:57 > 0:02:00to a time when much of Europe looked like the Bahamas.
0:02:02 > 0:02:06A time when these warm tropical seas were home to giant predators.
0:02:08 > 0:02:10Some of which, have left their mark
0:02:10 > 0:02:12etched in stone.
0:02:13 > 0:02:15This cliff face in Switzerland
0:02:15 > 0:02:17is carved with a series
0:02:17 > 0:02:20of enormous gouges and grooves.
0:02:20 > 0:02:22Many over nine metres long.
0:02:23 > 0:02:26The entire rock face is actually
0:02:26 > 0:02:27one huge fossil,
0:02:27 > 0:02:31an upturned slab of Jurassic Ocean floor.
0:02:31 > 0:02:33And the marks were left by a predator
0:02:33 > 0:02:36as it hunted for food.
0:03:03 > 0:03:05Sharks like this squatina
0:03:05 > 0:03:08are similar to angel sharks which still exist today.
0:03:12 > 0:03:15It's an ambush predator and lies in wait.
0:03:25 > 0:03:27But in these seas there are bigger hunters.
0:03:31 > 0:03:33This is Kimmerosaurus.
0:03:33 > 0:03:36They belong to a group called plesiosaurs.
0:03:38 > 0:03:41At six metres long,
0:03:41 > 0:03:44they're one of the Jurassic Ocean's most successful hunters.
0:03:46 > 0:03:49And also one of the most common.
0:03:55 > 0:03:57And it's this unusual hunting method
0:03:57 > 0:04:00that left its trace on the ocean floor
0:04:10 > 0:04:13We now know that the rock face in Switzerland
0:04:13 > 0:04:17is etched with the marks of hunting plesiosaurs.
0:04:18 > 0:04:21But these giants were not the king of the seas.
0:04:21 > 0:04:26Many of the fossils show evidence of having been violently ripped apart.
0:04:31 > 0:04:32Clearly, there were
0:04:32 > 0:04:34much, much bigger predators
0:04:34 > 0:04:36lurking in these seas.
0:04:37 > 0:04:41In 2008, in an island in the high Arctic,
0:04:41 > 0:04:44a fossil was dug out of the frozen earth.
0:04:44 > 0:04:49Its skull alone was nearly twice that of T-rex.
0:04:49 > 0:04:52This was an enormous killer.
0:04:53 > 0:04:57A killer, the like of which had never been seen before.
0:05:12 > 0:05:15More than 15 metres long,
0:05:15 > 0:05:17and weighing about 45 tonnes,
0:05:17 > 0:05:21this is the most powerful marine reptile ever discovered.
0:05:36 > 0:05:40Twice as big as most Jurassic Ocean predators...
0:05:43 > 0:05:44..this is Predator X,
0:05:44 > 0:05:46an animal
0:05:46 > 0:05:50that must go down in history as one of the ocean's most deadly hunters.
0:06:06 > 0:06:08And it's prey like Kimmerosaurus
0:06:08 > 0:06:11that are in its sights.
0:06:26 > 0:06:29Skull analysis of giant killers
0:06:29 > 0:06:31like Predator X,
0:06:31 > 0:06:33suggests that they hunted their prey by smell...
0:06:35 > 0:06:38..channelling water through special internal nostrils,
0:06:38 > 0:06:42allowing them to silently hone in on their target.
0:06:59 > 0:07:00By analysing their anatomy,
0:07:00 > 0:07:03we've calculated that Predator X
0:07:03 > 0:07:07could move up to five metres per second -
0:07:07 > 0:07:10fractionally faster than a Kimmerosaurus.
0:07:14 > 0:07:17The kimmerosaurs only defence
0:07:17 > 0:07:21is to head for the refuge of shallow water.
0:07:33 > 0:07:38This time, Predator X's size works against him.
0:07:44 > 0:07:47Unable to hunt efficiently in shallow water...
0:07:48 > 0:07:52..means that the Kimmerosaurus can use this as a refuge.
0:07:55 > 0:07:59A subtle advantage that makes the difference between life and death.
0:08:13 > 0:08:15Predator X and Kimmerosaurus
0:08:15 > 0:08:17are just one example
0:08:17 > 0:08:19of a predator-prey relationship
0:08:19 > 0:08:21locked in a fight for survival.
0:08:23 > 0:08:25In the western states of North America
0:08:25 > 0:08:28is one of the richest sources of dinosaur fossils.
0:08:28 > 0:08:31It's known as the Morrison Formation.
0:08:31 > 0:08:33Recently, these rocks
0:08:33 > 0:08:35have given us a tantalising glimpse
0:08:35 > 0:08:37of how two dinosaurs adapted together
0:08:37 > 0:08:40to protect themselves against another deadly predator...
0:08:42 > 0:08:45..Stegosaurus and Camptosaurus.
0:08:46 > 0:08:48Fossils of these two species
0:08:48 > 0:08:49are almost always found
0:08:49 > 0:08:51in the same area.
0:08:52 > 0:08:54In 2008,
0:08:54 > 0:08:55footprints of the two
0:08:55 > 0:08:57were recovered from the same site.
0:09:02 > 0:09:05It seemed that they lived alongside one another.
0:09:06 > 0:09:09But why would two unrelated plant-eaters
0:09:09 > 0:09:10live together?
0:09:16 > 0:09:18Stegosaurus -
0:09:18 > 0:09:19a heavily armoured tank
0:09:19 > 0:09:22with a deadly weapon at the end of its tail...
0:09:22 > 0:09:24known as a thagomizer.
0:09:27 > 0:09:30Camptosaurus - a much smaller plant-eater
0:09:30 > 0:09:32with no obvious defences.
0:09:35 > 0:09:36DINOSAUR GROANS
0:09:43 > 0:09:45Skull analysis shows
0:09:45 > 0:09:48that Camptosaurus has bigger eyes -
0:09:48 > 0:09:52and relative to its body - a much bigger brain.
0:09:55 > 0:09:58Camptosaurus appears to be a lookout.
0:10:06 > 0:10:09While the armoured Stegosaurus provides the muscle.
0:10:09 > 0:10:10STEGOSAURUS GROANS
0:10:13 > 0:10:16It's likely Camptosaurus and Stegosaurus
0:10:16 > 0:10:20stuck close together for mutual protection...
0:10:26 > 0:10:28..in a world where danger is ever-present.
0:10:31 > 0:10:35CAMPTOSAURUS CROWS
0:11:01 > 0:11:03CAMPTOSAURUS GROANS
0:11:17 > 0:11:19CAMPTOSAURUS CROWS
0:11:24 > 0:11:26CAMPTOSAURUS CROWS
0:12:05 > 0:12:08CAMPTOSAURUS CRIES
0:12:42 > 0:12:47ALLOSAURUS GROWLS
0:12:47 > 0:12:49Allosaurus -
0:12:49 > 0:12:53a one-and-a-half-tonne ambush hunter with a lethal bite.
0:12:53 > 0:12:58The world had never known a predator like it.
0:12:58 > 0:13:02But having lost the element of surprise,
0:13:02 > 0:13:06it's now faced with the prospect of either starving...
0:13:06 > 0:13:10or facing the most well-protected giant of the Jurassic.
0:13:11 > 0:13:13ALLOSAURUS GROWLS
0:13:13 > 0:13:15STEGOSAURUS BELLOWS
0:13:24 > 0:13:26Virtually impregnable from behind,
0:13:26 > 0:13:31a predator needs to try to attack the stegosaurs from the front.
0:13:31 > 0:13:34ALLOSAURUS GROWLS
0:13:38 > 0:13:39ALLOSAURUS ROARS
0:13:40 > 0:13:42STEGOSAURS BELLOW
0:13:45 > 0:13:47STEGOSAURUS HOWLS
0:13:53 > 0:13:54STEGOSAURUS BELLOWS
0:14:23 > 0:14:25ALLOSAURUS PANTS
0:14:25 > 0:14:28The evidence for encounters such as these is incredible.
0:14:30 > 0:14:32Fossil finds of 2005,
0:14:32 > 0:14:34directly link
0:14:34 > 0:14:36these two great animals in battle,
0:14:36 > 0:14:38revealing the unmistakeable signs
0:14:38 > 0:14:39of injury.
0:14:39 > 0:14:41A Stegosaurus back plate
0:14:41 > 0:14:42was discovered
0:14:42 > 0:14:44with a u-shaped bite taken out of it.
0:14:44 > 0:14:46A bite mark that fitted
0:14:46 > 0:14:48the Allosaurus' jaws perfectly.
0:14:49 > 0:14:52Even more amazing
0:14:52 > 0:14:54was an Allosaurus vertebra.
0:14:54 > 0:14:56It had a massive impact wound.
0:14:57 > 0:14:59The wound appeared to have been made
0:14:59 > 0:15:02by a Stegosaur's thagomizer.
0:15:03 > 0:15:05The blow being so powerful
0:15:05 > 0:15:06it punched a hole in the bone
0:15:06 > 0:15:08of the Allosaurs' spine.
0:15:09 > 0:15:11What's more incredible
0:15:11 > 0:15:14is that the injured bone shows signs of healing.
0:15:15 > 0:15:18This Allosaurus survived.
0:15:21 > 0:15:25The balance of power between predator and prey is a fine one.
0:15:26 > 0:15:28Prey continually evolve
0:15:28 > 0:15:29different strategies
0:15:29 > 0:15:31to avoid predators.
0:15:31 > 0:15:33Both with their bodies,
0:15:33 > 0:15:34like Stegosaurus,
0:15:34 > 0:15:36and their behaviour
0:15:36 > 0:15:37like Camptosaurus.
0:15:40 > 0:15:43And in the Jurassic oceans, we have evidence to suggest
0:15:43 > 0:15:46that plesiosaurs protected their young...
0:15:47 > 0:15:51..by finding sanctuary in shallow water nurseries.
0:16:02 > 0:16:04But such lagoons
0:16:04 > 0:16:07won't always deter a hunter.
0:16:24 > 0:16:29And a rising tide gives this predator a glimmer of hope.
0:16:42 > 0:16:43PREDATOR X ROARS
0:16:45 > 0:16:47But in this shallow water,
0:16:47 > 0:16:51the huge Predator X can't use its power.
0:16:51 > 0:16:54The smaller, agile Kimmerosaurus
0:16:54 > 0:16:57can easily outmanoeuvre
0:16:57 > 0:16:58the lumbering killer.
0:17:02 > 0:17:05However, the Kimmerosaurus can't permanently protect itself
0:17:05 > 0:17:07in this sanctuary.
0:17:08 > 0:17:11They need to venture into deeper water to feed.
0:17:16 > 0:17:20And that is where Predator X has the advantage.
0:17:26 > 0:17:30Successful predators need to play a waiting game.
0:17:30 > 0:17:33ALLOSAURUS GROWLS
0:17:36 > 0:17:41Allosaurus is the most common killer in these lands.
0:17:45 > 0:17:46Nine metres long,
0:17:46 > 0:17:49with a battery of saw blade-like teeth
0:17:49 > 0:17:51and powerful, clawed forearms -
0:17:51 > 0:17:54Allosaurus is a formidable hunter.
0:17:57 > 0:17:59ALLOSAURUS GROWLS
0:18:03 > 0:18:04It shares the plains
0:18:04 > 0:18:07with dozens of species
0:18:07 > 0:18:09of plant-eating dinosaurs.
0:18:16 > 0:18:20A lone Camptosaurus, away from the protection of Stegosaurus...
0:18:21 > 0:18:25..should be easy pickings for a hunting Allosaurus.
0:18:43 > 0:18:46Allosaurus teeth were serrated front and back,
0:18:46 > 0:18:49perfectly evolved for tearing through flesh.
0:18:49 > 0:18:52However, recent research has indicated
0:18:52 > 0:18:56that Allosaurus' bite was surprisingly weak.
0:18:56 > 0:19:00Calculations suggested its bite was less powerful than a lion's -
0:19:00 > 0:19:03despite being seven times more massive.
0:19:07 > 0:19:10So, just how did this Jurassic monster
0:19:10 > 0:19:12hunt and kill?
0:19:24 > 0:19:27The answer is with an element of surprise.
0:19:43 > 0:19:45Camptosaurus relies
0:19:45 > 0:19:48on its keen senses to avoid predators.
0:19:56 > 0:19:59Allosaurus on the other hand,
0:19:59 > 0:20:02is a fast and powerful ambush hunter.
0:20:02 > 0:20:04Faster than Camptosaurus.
0:20:45 > 0:20:49A one-and-a-half-tonne killer can't run fast for long.
0:20:56 > 0:20:59It's a question of speed versus stamina.
0:21:12 > 0:21:15CAMPTOSAURUS SHRIEKS
0:21:15 > 0:21:17ALLOSAURUS ROARS
0:21:28 > 0:21:31ALLOSAURUS ROARS
0:21:36 > 0:21:39Despite the apparent weakness of its bite,
0:21:39 > 0:21:43Allosaurus did in fact have a deadly killing method.
0:21:45 > 0:21:47Its skull could withstand a force
0:21:47 > 0:21:50more than 15 times as great as its bite.
0:21:55 > 0:21:59This meant that Allosaurus used its head like an axe.
0:21:59 > 0:22:04Its strong neck muscles driving its top jaw into its prey.
0:22:05 > 0:22:07With every impact, the serrated teeth
0:22:07 > 0:22:10would tear through its prey's flesh.
0:22:10 > 0:22:14The victim dying, through a combination of shock and blood loss.
0:22:15 > 0:22:19It isn't pretty, it isn't clinical...
0:22:19 > 0:22:21but it's ruthlessly efficient.
0:22:24 > 0:22:27However, making a kill
0:22:27 > 0:22:29never actually guarantees a meal.
0:22:30 > 0:22:32Because here,
0:22:32 > 0:22:35Allosaurus isn't the only killer in these parts.
0:22:35 > 0:22:37DINOSAUR ROARS
0:22:37 > 0:22:39Saurophaganax.
0:22:42 > 0:22:46At 12 metres, it is the biggest carnivore in the region.
0:22:52 > 0:22:54SAUROPHAGANAX ROARS
0:23:11 > 0:23:14And one of the advantages of being so big
0:23:14 > 0:23:18is that stealing another's kill is that much easier.
0:23:25 > 0:23:28Giant predators like Saurophaganax and Allosaurus
0:23:28 > 0:23:31used their power and size to dominate their domain
0:23:31 > 0:23:33and all those within it.
0:23:36 > 0:23:40And the story was no different in the Jurassic oceans.
0:23:44 > 0:23:47These are the bones of Plesiosaur.
0:23:49 > 0:23:51They appear to have been broken into fragments.
0:23:51 > 0:23:54And many of these show indications
0:23:54 > 0:23:56that they didn't die of natural causes.
0:23:56 > 0:24:00It looks more like they were violently dismembered.
0:24:02 > 0:24:05One particular fossil gives us a chilling idea
0:24:05 > 0:24:08of how these plesiosaurs might have been killed.
0:24:10 > 0:24:12It consists of a skull
0:24:12 > 0:24:15with a few vertebrae still attached
0:24:15 > 0:24:16but nothing else.
0:24:17 > 0:24:19All these dismembered fossils
0:24:19 > 0:24:21were found in deeper waters,
0:24:21 > 0:24:24where plesiosaurs need to feed
0:24:24 > 0:24:27but where they're in the greatest danger.
0:24:27 > 0:24:30This animal is in the worst possible place -
0:24:30 > 0:24:32hunting alone at the surface,
0:24:32 > 0:24:37where it's most vulnerable to attack from below.
0:24:50 > 0:24:52In deep water,
0:24:52 > 0:24:55Predator X can use its full power.
0:25:15 > 0:25:17Although, injured and stunned
0:25:17 > 0:25:20this plesiosaur is armed with a vicious bite.
0:25:20 > 0:25:23So, Predator X still needs to be wary.
0:25:45 > 0:25:48Severely wounded, now the only sanctuary
0:25:48 > 0:25:51is the shallow water of the nursery.
0:26:39 > 0:26:41Predator X's bite is formidable,
0:26:41 > 0:26:44estimated to be four times that of T-rex.
0:26:44 > 0:26:48Biting hard, it perforates the body,
0:26:48 > 0:26:51cutting through muscle and bone before shaking it to pieces.
0:26:58 > 0:27:01It's almost certain that the bite marks on the fossil plesiosaur
0:27:01 > 0:27:04were made in this way.
0:27:08 > 0:27:10And the position of the marks also indicated
0:27:10 > 0:27:13the attack came from below.
0:27:20 > 0:27:21The never-ending battle
0:27:21 > 0:27:23between predators and their prey
0:27:23 > 0:27:25is a finely balanced one.
0:27:28 > 0:27:32However, for the most successful and enduring predators,
0:27:32 > 0:27:36the struggle to survive is always tipped in their favour.
0:27:42 > 0:27:45And predators like Predator X,
0:27:45 > 0:27:48a killer with one of the most powerful bites ever known...
0:27:48 > 0:27:53ruled the oceans for more than 100 million years.
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