"What happened when killer dinosaurs waged war?" "Whose blood was spilt?" "And who reigned supreme?" "To answer these questions, a team of skilled engineers will be building bio-mechancial replicas of dinosaur weaponry." "And then they'll test them." "For the first time in 65 million years, the true power of these dangerous dinosaurs will be unleashed." "The terrifying predator Tyrannosaurus rex squares up to the monstrous Triceratops..." "This is a scene that's been played out many times in the movies." "But did it every really happen?" "And if these two dinosaurs did fight - who would have been victorious?" "These are questions that have been puzzling scientists ever since the dinosaurs were first discovered." "And now they're using a completely new method of research to help them find the answers:" "biomechanical replicas of T rex and Triceratops." "But however futuristic the research techniques, all investigations begin with the ancient fossil bones...." "The first skeleton of T rex was found just a hundred years ago." "Since then there have been about 24 more unearthed..." "Not one of them is 100% complete." "But scientists can tell a surprising amount from the fossil bones." "Like size for instance." "T rex was unquestionably huge - forty foot long from head" "When scientists look really closely at the skeleton, they can see where the muscles and tendons attached - and so flesh out T rex." "It's even possible to determine the texture of the skin, by studying impressions left in ancient rocks." "So, putting together the most accurate evidence, taken from the very latest research - meet Tyrannosaurus rex... lt seems certain that this iconic dinosaur was huge, and fearsome." "But was he really capable of overpowering the other big guy on the block?" "Triceratops: 'three horned face' and most famous of the horned dinosaurs." "At eight tons, this would have been some heavyweight for T rex to take on." "There are only three fossil skeletons of Triceratops for scientists to work on and none of these are complete." "But it's obvious from its size and enormous skull that this dinosaur would have made a fearsome opponent." "So Triceratops versus T.Rex." "They both lived in North America at the same time but what exactly would have happened when they met?" "Until very recently, there was absolutely no scientific proof that they had anything to do with each other at all." "But then Greg Erickson took a close look at a fragment of a pelvis from a 65 million year old Triceratops." "On the pelvis he's found some intriguing wound marks..." "For instance, lf you look here there are some gouges along the top." "There's a really deep puncture mark right here." "ln fact if one looks all over this specimen you'll find over 80 of these punctures and cut marks." "These are bite marks." "Some other beast had been taking chunks out of this Triceratops." "So who was the culprit?" "We have a real whodunit mystery." "Using a common forensic technique," "Greg pushes some dental putty into one of the deep wound marks to help identify the mystery diner." "Aha, there we go, we have a very nice cast here of the tooth." "This is a shape that is very familiar to me." "This is reminiscent of a therapod dinosaur tooth and a very nice match for this animal Tyrannosaurs Rex." "I think this is pretty good smoking gun evidence that T.Rex fed on this triceratops 65 Million years ago." "It's often presumed that T rex ate Triceratops, but this is the first scientific evidence." "Though it doesn't prove that T rex killed Triceratops." "The supposedly invincible carnivore might have found this dead animal lying in its path." "Was the tyrant king really capable of slaying a huge Triceratops?" "Greg Erikson believes that T rex's teeth were certainly up to the job." "The teeth of an animal can reveal a great deal about what it was doing for a living and it's very clear that T rex was 15,000 pounds of gut crunching terror." "T rex possessed some of the most robust teeth, some of the largest teeth of any dinosaur." "They're recurved, there was a serrated steak knife-like edge on the back and the front." "If this animal was a predator, it was probably the most lethal predator that ever lived." "So how much damage could T rex do to a live Triceratops?" "Dave Payne and John Pennicott are skilled engineers who usually make special effects for movies:" "Shark Movies, Bond movies and many more." "This time they're going to help the scientists to investigate the power of T rex's jaws, by building a life-size, fully working model of a T rex head." "It will be based on Stan, one of only three near complete fossil skulls." "The replica will be made by hand, faithfully following the proportions of the T rex fossil." "The biomechanic has to be incredibly strong because the fossil evidence shows that, when T rex was feeding, it could bite through bone." "So they decided to make the head from pure steel." "The teeth have to be cast individually at a local foundry and are also made from steel." "But the technicians need to know how much force to use to power the biomechanic's jaws." "Scientists can deduce from the skeleton that T rex had huge jaw muscles." "Before the team can test whether T rex was tough enough to take on a living Triceratops they need to know exactly how powerful these muscles were." "Alligators and crocodiles have the most powerful bites of any living animal." "They're also among T rex's closest living relatives." "Paleontologist, Greg Erikson calculates that, if he can measure the force of an alligator's bite, that measurement could be scaled up to get the force of a T rex bite." "So, Greg hitches a ride with the Florida Alligator Control who are hoping to catch a rogue 'gator that has been making a meal of the local dogs." "Crikey, she's a fine one!" "Greg's caught a whopping 12ft animal, weighing around 450 lbs - that's the same weight as 3 men." "This wild rogue alligator is the perfect subject for Greg's bite test." "All he has to do is insert the biteometer where it counts." "Actuality - bite test, 2,209 bite ... 1 Ton." "So now Greg can scale up that one ton measurement to work out how strong the bite of a T rex would be." "We're close to release, everyone ready?" "After 3 months of painstaking engineering and careful scientific calculations, the bio-mechanical T rex head is ready to test." "Based on his work with alligators," "Greg has calculated that T rex would have had a bite force of at least 4 tons." "The bone would've had to been so strong that the only way to replicate it is by using steel." "And the enormous muscle power is provided by a hydraulic piston." "It's time to test true strength of the jaws...." "This is just part of a cow's leg bone." "T rex had the strongest bite of any animal ever known." "Eight times more powerful than a lion." "Four tons of brute force completely pulverises the bone." "This dinosaur could certainly have delivered a killer bite." "The bio-mechanical bite test doesn't prove that T rex really did attack Triceratops." "But amazingly, the fossil evidence does exist..." "John Happ has some more fragments from a Triceratops, this time dug up in Montana, USA." "First a fossil of a damaged horn..." "When we first found the left brow horn we were disappointed because about a 1/3 of the horn is missing." "These are bite marks.... ...the end of the horn was bitten off." "The shape of the teeth marks proves once again that the culprit could only be T.Rex" "Bite marks alone still don't prove T.Rex attacked Triceratops." "But John has noticed something else." "We found some additional bite marks." "A line made where T.Rex's tooth raked into the frill." "But there is something strange about this line." "Where you might expect a clean-cut groove from the tooth - there is an unusual ridge." "And when John x-rays the ridge the incredible truth is revealed." "You can see at the first score mark an area of dense bone." "This is an indication that the bone re-healed." "The bone re-healing is the crucial evidence." "It proves that Triceratops was attacked by T. rex while it was alive." "Triceratops must have survived for long enough for the wound to heal." "It's the first time scientists can say for certain that T rex wasn't simply a scavenger - because they know that, at least on one occasion, it did attack Triceratops." "They know that T rex grabbed its horn..... and broke it..." "They also know that T rex grabbed the frill of the same animal with enough force to crunch through bone." "But there is still much more to discover about the relationship between these two heavyweights." "If T rex ambushed Triceratops he would have had to been quick." "So how fast could T rex run?" "He's been depicted as everything from a lumbering hulk to an animal that can out pace ajeep." "Some have even speculated that these legs could power him up to 45 mph." "So what's the truth.?" "Jim Farlow of Indiana University is investigating one of the world's finest collections of footprints of meat-eating dinosaurs." "Here's a real nice one right here, starts out here with a left footprint and then we go here to the next right footprint and beyond here is another left footprint of the same animal." "By measuring the distance between the footprints," "Jim can calculate how fast this dinosaur was moving..." "Well judging from the length of the stride, I'd guess that this beast is moving at a fast walk... maybe 7-8 mph which is sort of a fast jog for a human being." "So can these footprints help scientists to work out the top speed of T.Rex?" "Well there's a problem because T rex was much larger than the dinosaurs that left these prints." "Now if we had a tyrannosaurus stride.... and if we start at about where that footprint is... the same foot would now come down.... going to be about here." "And that's just a walking stride..." "So you can see in order to encompass the entire length of stride of a running tyrannosaurus - you're going to have to have a very big surface and it might be hard to get one that large." "ln fact no footprints of a running T.Rex have ever been found..." "So to consider how fast a tyrannosaurus could run, we may have to use something other than footprints." "John Hutchinson is studying the way animals run at the Royal Veterinary College in Hertfordshire, England." "He's trained Sharon the ostrich to work-out on a running machine." "And she's helping him work out how fast T rex might have run." "Ostrichs' legs are very similar to T rex's... pretty skinny with long tendons stretching down to the toes and all the muscles piled up at the top." "Look at this ostrich.... an ostrich can run faster than any human." "How does it do that?" "Well it has huge leg muscles about 15% of the body weight in this ostrich." "Those muscles produce a lot of force." "ln fact they can power Sharon's legs up to an impressive 40 miles an hour." "These leg muscles help the leg work like a spring and the body is acting like a great weight that is bouncing up and down on those springs... much like a pogo stick." "That's what makes the ostrich such a fast animal it's pogo stick-like legs and big muscles." "So, could T rex run as fast as an ostrich?" "By scaling up from Sharon, John has worked out that to run at 40 miles an hour," "T rex would have needed muscles as large as this.... simply impossible." "Clues from the bones suggest that it probably had muscles much more like this." "So T rex was definitely slower than an ostrich." "We figure from our calculations that a T.Rex might be able to move as fast as 25mph maximum, probably a bit less than that." "It doesn't sound that fast but it's as fast as an Olympic sprinter and those speeds aren't bad at all for an animal that big." "25mph if you saw a T.Rex going that fast would be very impressive." "T Rex could run faster than most humans, but could it run faster than Triceratops?" "Triceratops was built rather like a sumo wrestler and its short front legs would have made big strides impossible." "John Hutchinson has calculated that Triceratops could run no faster than 15mph." "So now its obvious as to who would catch who." "But is it?" "Triceratops had one more trick up its sleeve..." "Scientists are comparing the agility of the two dinosaurs using a rather unconventional experiment on the salt flats of Utah." "Dave Carrier has discovered there is a downside to being a 40-foot long T rex running on just 2 legs." "The problem that T-Rex had is that the legs were in the middle and they had a long body, head and neck out in front and then a long heavy tail out behind." "T rex has a pivot in the middle with a considerable amount of weight spread out on either side." "Triceratops, on the other hand had all its weight centred solidly above four legs." "So who had the advantage when it came to a chase?" "Well, this experiment requires a certain amount of imagination...." "Dave's the Triceratops, his student is T rex." "ln the pack on my back is twenty six pounds the same weight as the T-Rex behind me is carrying." "The difference in the T-Rex the weight is a metre in front of the legs and a metre behind the legs, in my case I'm much more similar to the triceratops, in that the weight is carried close to my back." "If we were to run, straight ahead as we're doing now the T-Rex has no problem tracking me." "If I were to turn in a gradual arc the T-Rex could track me perfectly fine." "However watch what happens on the second or third turn." "First turn to the left...." "To the right...." "Left...." "Triceratops is gone!" "T.Rex's body shape put it at a serious disadvantage." "It would have been a lot better off if it could have reduced the weight at the front end..." "Perhaps by losing those huge teeth?" "Or reducing the size of its head?" "Obviously T-Rex can't change its anatomy, if it had it would no longer be T-Rex." "After all it's the big head and big teeth that give this superstar its Rex appeal." "So what, realistically, could it have done to improve its agility?" "The one thing it might have been able to do is change it's posture when it was running." "So what we're suggesting for T-Rex, that instead of running with the head and neck stretched out horizontally they would have actually pulled their neck back into an S shape." "They may also have raised the tail up off of the horizontal to an angle above the ground." "Both of these changes would have greatly increased the agility of T-Rex" "But speed and agility aren't the whole story... lf T rex was clever enough, he might have been able to plan his attack and outsmart Triceratops." "But to investigate that theory scientists would have to look inside its brain." "lmpossible?" "Scott Rogers doesn't think so." "He's one of the few people in the world who has tried to get into the mind of a dinosaur." "One of the most difficult aspects of studying the behaviour of an extinct species is trying to find its brain." "The problem with the brain is, is it tends not to fossilise. lnstead it tends to rot." "Up until now all scientists had to work on were the mud filled spaces inside the skull where the brain used to be... the endocast." "But Scott had an ingenious idea - to look inside this endocast using the latest medical scanner." "He wanted to see if there were any traces of the brain left behind in the fossilised mud." "What we found was something quite extraordinary." "For the very first time we are really looking at material in here that we believe reflects the actual structure of the brain." "The white, blobby mass reveals the true shape and structure of a dinosaur brain, for the first time ever." "When Scott compared the shape of the brain with the brains of other animals, he made a fascinating discovery." "By comparing that with modern species what we find is that brain resembles very closely the brain of an alligator." "If T rex's brain was similar to an alligator's, then this provides a clue to how T rex behaved." "An alligator's thought process is extremely simplistic." "If it smells something that it thinks is a food item it turns to it, hits it swallows it and that's then end of it." "It's not going toss it around think about well maybe I should've attacked it." "May be I should have picked at it." "No it's going to immediately respond and have a very distinct behaviour." "Just like an alligator, T rex would sense something and go after it." "No questions asked." "But what about Triceratops - would it have been able to outsmart T rex?" "If we look at this model of a Triceratops what we find is something strikingly different." "ln this case we see that the brain size, which would be right in this region, is almost the same size as the spinal cord region." "What that tells us is as sensory information came into the brain it basically went straight through." "So no time for thinking" " Triceratops was even more stupid than T rex." "It probably did very, very little when a tyrannosaurus came up, it would protect itself, it might charge but it had a limited ability to respond." "He might have been stupid, but the fossil evidence confirms that Triceratops did survive an attack by T rex." "So the lumbering 3-horned vegetarian must have been able to fight back." "The horns look like highly effective offensive weapons." "But how exactly did it use them?" "Andrew Farke, from Stony Brook University, New York, is an expert on horned dinosaurs." "It's very easy to think that perhaps Triceratops, when it was confronted by a hungry T. Rex, something that was threatening it, that it would have immediately charged and tried to use it's horns with all the force it had." "A modern animal that charges just like this is a rhino." "It has a sharp horn and when it's provoked, it'll charge at full pelt, using all its weight to ram its opponent." "So at first glance it definitely might appear that Triceratops was charging like a rhino." "This is a theory that has never been tested." "Until now." "To find out exactly what kind of damage a charging Triceratops would have inflicted on T rex, the crew of bio-mechanic experts set about building a life size replica of a Triceratops skull." "The model makers began by examining a cast of an existing fossil." "But to create a true replica, the they had to find a material that had the same properties as the original bone." "They tested 20 different combinations of resin composites before they found one that had exactly the same tensile strength." "It was important to make sure that the model behaved just like a real animal in an impact." "The team of experts worked for months to meticulously prepare for the bio- mechanical test." "Finally they have an accurate model of the skull built from a specially developed resin composite." "They have a top charge speed of 15 miles an hour." "And they have a weight for a Triceratops of 5-8 tonnes." "And now they are ready for the test - a crash test." "Here in this hanger they normally in crash test cars." "But this time its dinosaurs." "This is a unique experiment on a truly spectacular scale." "This is about as close as we could possibly get to what a real Triceratops skull would have been like in life." "This whole thing is mounted up on this apparatus - its going to send it barrelling down here and then run smack into our simulated T rex." "The T rex stand in doesn't look much like T rex but it has all the qualities of T rex." "The muscle and flesh is represented by crushable honeycomb aluminium." "This is covered by the 'T.Rex skin' - made from thin sheet aluminium and leatherette." "For the first time ever, this bio-mechanical experiment is going to reveal what would have happened if Triceratops charged at full speed into the belly of T rex." "The skull clearly wasn't strong enough for Triceratops to charge like a rhino and ram T rex.." "ln slow motion we can see what happened." "The sharp, narrow horns sliced easily through the simulated T rex but the broader beak and nose couldn't cut through the flesh and muscle." "Forces built up to 6 tons and the Triceratops's skull started to fail - fracturing at its weakest point." "This would have meant certain death for the colossal vegetarian." "So its back to the drawing board to find out how Triceratops could have survived an attack by T rex." "But, the outcome of any predator prey battle is often determined by who sees who first." "So how well could T rex see?" "The size of the eye socket suggests that the eyeball was about the size of a grapefruit, with plenty of room for the sensors needed for fairly sophisticated vision." "Good eyesight would have been very useful when it came to hunting down Triceratops..." "Kent Stevens has been using laser measurements to investigate the link between the position of T rex's eyes and its behaviour." "Modern predators, like cheetahs who chase down their prey, have eyes right at the front." "This gives them good 3D vision and a better ability to track their prey." "When Kent measured the eye position of T rex, he was surprised at what he saw." "ln the case of T-Rex, I didn't see just a very large reptile; this is closer to like a wolf," "The snout drops down... relative to the plane of the eyes, it becomes narrower... so this could look down and over its snout providing a very broad field of view ahead of it." "The position of T rex's eyes gave it good 3D vision, like that of a modern hunter " "so it was well able to actively chase down Triceratops." "So how well could Triceratops see him coming?" "Modern animals that need to keep on the alert for predators have eyes on the sides of their heads." "Kent could see that Triceratops was just the same." "It had side-mounted eyes to keep a lookout for potential killers." "But it also had blind spots...." "This whole structure here, part of the support of these horns, obscures forward vision." "Another thing is this large frill;" "this large frill produced a very large blind spot behind the animal." "It could have compensated for it partly by swinging its head from side to side so it could look over one shoulder or another at a time." "It was a potential vulnerability that a predator could certainly have exploited." "If Triceratops was attacked by T rex it would have had to defend itself." "But how exactly did it do that?" "Andrew Farke, the Triceratops horn expert, has a new theory." "He's been re-examining some triceratops fossil skulls and has found some tell tale wound marks that no one's noticed before." "Perhaps there's a little bit of bone that's missing, in front of the eye." "On the cheek you might find an odd hole, ...in some specimens there are abnormalities on the frill." "And from the shape of the marks he can tell what caused the damage..." "Triceratops going horn to horn with each other." "Now we know for sure that Triceratops was using its horns against its own kind, its very likely it was also using them against T rex." "Triceratops didn't use its horns to ram T rex so it most likely used them like this " "flicking its head to gore its attacker." "Potentially lethal." "But an attack by T rex's jaws would have been just as brutal." "Greg Erikson has been investigating exactly how T rex attacked its victims." "I think the best analogy that can be made for the feeding of T rex amongst living animals is the great white shark." "This predator doesn't just crunch on flesh and bone, but rips out great chunks of its victim." "Greg has found evidence on his fossil Triceratops pelvis that T rex behaved just like the shark." "What you see is this animal bit down into the bone and then pulled backwards removing large chunks of bone and leaving a furrow behind." "Now if we look at t a bite mark that is made by the Great White Shark, such as this mark here, that was made on a whale vertebra, we see almost the exact same pattern." "The tooth was pushed down into the bone here and pulled across leaving a furrow very much like what we see on the Triceratops pelvis." "Using the steel T rex head, the bio- mechanics team are going to find out what kind of effect this brutal bite would have had on Triceratops." "And their stand-in for Triceratops?" "A side of pork." "To reproduce the ripping motion, they're going to use an industrial strength forklift." "Just like a shark, there were two distinct parts to a T rex bite." "First, the deep penetrating crunch through flesh and bone" "And then, using its full body weight," "T rex pulled backwards, ripping through the flesh." "A devastating attack." "The experiment proves that T rex would have been able to bite off 330 pounds of meat in one go - about the weight of two men." "But its doubtful that it could have swallowed that amount." "By examining the skull of T rex, scientists have concluded that it would have been able to swallow a chunk of meat about the weight of an entire pig." "Now they've built the bio-mechanical T rex head, the team are keen to test it to the limit...." "Just for fun, they want to see how a twentieth century icon stands up to an icon of a very different era..." "The force of this bio-mechanical bite is no greater than the force of a T rex bite, as calculated by the scientists." "So - who would have had the advantage when T rex hunted Triceratops?" "What's the evidence?" "T rex was certainly superior when it came to eyesight - it had excellent vision." "Whilst Triceratops had a crucial blind- spot." "T rex could run quite fast on a straight run but its body shape gave it serious problems with manoeuvrability." "Triceratops was slower, but much more agile." "T rex had formidable weapons with its powerful jaws and huge, serrated teeth" "But Triceratops could fight back - using its horns to gore its attacker." "The evidence suggests an even match - and at the end of the day it may well have been a case of which one was the first to make a mistake...." "Using all the data from the research, and the biomechanical tests, it's now possible to finally and faithfully recreate the titanic confrontation that might well have happened, 65 million years ago...." "This impressive vegetarian has proved to be a formidable opponent." "One false move by T Rex, and the consequences would have been fatal" "ln the next programme - the truth about the two-legged meat-eater, Velociraptor." "It was much smaller than T rex but no less terrifying." "The technical team will build another life-size bio-mechanical model to find out exactly how this killer dinosaur used its legendary disemboweling claw..." "And all will be revealed about its gruesome secret."