Exploring The Dinosaur Kingdom 3 Hours of Amazing Discoveries

when dinosaur fossils were first pulled from the ground the appearance of the creatures was anyone's guess and how they lived was beyond comprehension but from Argentina to Wyoming great discoveries and bold new thinking suggest these ancient creatures were faster more agile and more complex than once imagined 65 million years after the last dinosaurs vanished they're more popular than ever they've escaped from museums and invaded our popular culture spawning Renaissance of the dinosaurs for over 150 million years group of animals unlike any today ruled our planet the dinosaurs their great success demands that we understand them but their remains are silent today scientists like Jack Herer are struggling to find what they were really like her is one of the paleontologists responsible for redefining our modern image of dinosaurs his groundbreaking discoveries and Keen insights have helped answer questions that have lingered for more than 100 years his Pioneer status attracts volunteers from all over the United States to Montana for his crash course in dinosaur excavation Bishop the students live in traditional Native American tepes designed to withstand howling winds that sweep off the nearby Rocky Mountains Herer believes that the focus of paleontology is changing you know by tonight it's instead of settling for knowing what dinosaurs look like we now need to know how they lived in the old days people were looking for display pieces they were looking for things to put in museum so they would go out they would find dinosaur they were looking for individual dinosaurs and they were looking for something big so they'd go out they'd find dinosaur they'd dig it up they'd bring it back they'd prepare it they' put it on display and then they go look for another one and they they weren't doing they weren't doing science they were mean it was it was more in line with sort of the PT Barnum Spirit nowadays most of us think are are very interested in how dinosaurs live in the 1970s Horner's research led him to the debate over the link between dinosaurs and birds an issue that's nag paleontologists almost since the beginning of the science as early as 1839 dinosaurs were classified as reptiles even though some had hip bones like modern birds not much was made of the similarity until 1861 when an astonishing fossil was pulled from German Quarry named archaeopteris it looked like small dinosaur but with one major difference it had feathers some scientists would later declare it the missing link between birds and dinosaurs but others refuted the idea because it lacked the specialized collarbone wishbone considered to be the fundamental trait of birds and their ancestors the dinosaur bird Theory gathered academic dust for 100 years in 1978 Herer found some hard evidence to all but resolve it chance encounter in Montana Rock Shop led him to the discovery of lifetime her and colleague were in their first year as excavators when they stopped at small fossil shop in Bina Montana not far from the Canadian border the owners were delighted when Herer was able to identify some of the fossils on display the bones that she had found turned out to be large duck bill dinosaur and as was leaving the shop she said by the way there are couple little bones here would like you to look at and she pulled out two tiny little bones both of which immediately recognized as baby duck bill dinosaur bones Herer was astonished he knew how incredibly rare baby dinosaur bones were and how much could be learned by finding more the shop owners agreed to close up early and take the dinosaur hunters to where the bones had been found think that's an interesting thing this one piece will make 52 layers watch on mobile devices or the big screen all for free no subscription required download now in pasture lands just east of the Rocky Mountains they showed Herer The Source it would become the Wellspring from which most of his future research would flow he proceeded to uncover numerous bones of baby dinosaurs buried in bow-shaped depression that he determined was nest it was historic find the first nest of baby dinosaurs ever discovered what's more that bones belong to previously unknown kind of Duckville dinosaur nearby he discovered hundreds more b-shaped depressions and realized that he'd found an entire nesting area many of them held fossilized eggs he called the new site egg Mountain only once before had dinosaur eggs and nests of this scale been found in 1923 the American Museum of Natural History in New York sent the flamboyant Roy chapen Andrews on lavish expedition to the GOI desert in Mongolia the Expedition found total of 50 eggs individually and in nests they wrapped their Treasures in camel hair and loaded them in crates to carry home herner's find was even more impressive it yielded eggs babies and for the first time actual dinosaur embryos inside their eggs 70 to 80 million years after they were formed toy the discoveries gave him the chance to study the development of dinosaurs from embryo to hatchling to adult much of his research focused on one question after dinosaur is hatched that they act more like birds or like reptiles reptiles emerge from the egg with strong legs and are able to fend for themselves right away but hatchling birds are too weak to care for themselves parent must remain at the nest feeding them until they can stand on their own significant behavioral difference Herer suspected that at least some dinosaurs cared for their young as birds do he looked for evidence in the eggs and the bones of the baby dinosaurs the eggs were deposited in clusters and it often takes Brute Force to free them from the surrounding Rock more delicate touch is used to scrape away the finer particles finally the specimens are wrapped in burlap and plaster to be transported back to the museum for further study in the lab Herer and his colleagues began experiments to determine if baby dinosaurs could stand on their own when they emerged from their eggs they needed to look at the structure of the hatchlings leg bones strong bones meant they could stand on their own and leave the nest like reptiles weak bones would suggest more helpless birdlike Behavior could discovery combined with Ingenuity bring us closer to understanding dinosaurs it has before every Discovery advances our knowledge of what the dinosaurs were really like and it goes beyond science the more dinosaur experts learn about these bizarre creatures the more fascinating they become to the public throughout the world hundreds of mums display thousands of dinosaur fossils to satisfy the growing interest and if people can't get to the museum the museum can sometimes come to them dinofest International is an annual exhibition of dinosaurs and ancient life from around the world in 1996 in two-e period nearly 200,000 people flocked to see prehistory come alive they were joined by world-renowned dinosaur experts artists and merchandisers dinest was the brainchild of paleontologist Don Wilber at the Philadelphia Academy of Natural Sciences we have dinosaurs for the first time put in one place from every continent so there are people interested in the wonderful animals from China dinosaurs from Canada US of course T-Rex is extremely popular and unpopular scares some kids scaring kids and adults alike are the recent Jurassic Park movies which have tallied the highest box office receipts of all time but perhaps the most stunning example of the public soaring fascination with Dinosaurs was seen at sues in 1997 the New York auction house put sue the most complete T-rex skeleton yet found on the Block had $700,000 noting $800,000 8 $900,000 now at9 at $900,000 now at 9 at $900,000 now two bids at1 million at $1 million now beting $1 million now 1.1 million 5.4 million telephone up front 5.5 5.6 5.7 three places 5.7 is in the center of the room still it's upfront then at 700 7,600,000 Fair Warning then at 7 million 600,000 up here 7,600,000 the highest bidder was the field museum in Chicago for single specimen it spent $7.6 million it was the most ever paid for dinosaur it seems that 65 million years after their Extinction dinosaurs are Conquering the Earth again they're selling today what remains of these once flourishing creatures is enough to draw huge crowds and excite the imaginations of scientists and the public alike if were dinosaur which dinosaur would want to be the biggest one if was dinosaur think would have going to be Tyrannosaurus Rex think I'd like to be turtle and watch Dinosaurs the the Triceratops brosaurus maybe tats for me they were the hook that captured me in career in science and among the topics care about our dinosaur extinction how they lived what they ate recreating worlds of the ancient past dest is just one of the latest events that brings the dinosaurs world back to life for over century scientists have displayed their discoveries to an admiring public even as they struggle to understand what these creatures were really like from the first meager discoveries the first public display of dinosaurs was in 185 four it occurred at Crystal Palace Park just outside of London some 40,000 people came to see life-sized sculptures of long vanished creatures on the banks of man-made lake stood replicas of many ancient animals and on Islands lur the most popular sculptures by far the dinosaurs huge and for the first time ever scientists had collaborated with artists to put Flesh on their bones each reconstruction represented the best that science had to offer it was thrilling and bit strange to public just getting used to the concept of of Extinction recreating three-dimensional sculptures from the bones of extinct animals had been tremendous undertaking English sculptor Benjamin Hawkins was hired to build the creatures under the supervision of scientists but very few dinosaur bones had been found by 1853 so the sculptures required some educated guesswork Hawkins used mix of creatures as his models lizards crocodiles and rhinoceros he labored for years on the project as it neared completion he held an unusual dinner party distinguished guests were served inside the belly of An Unfinished dinosaur model Hawkins had good reason to celebrate the Crystal Palace exhibition became the crowning Glory of new science that was just beginning to understand dinosaurs Through the Ages people had probably always come across dinosaur fossils but had no idea what they were in the 3r century ad dinosaur bones discovered in China were thought to be the remains of dragons ancient Greeks believe they were from race of Giants it wasn't until the 18th century that Europeans on the brink of the Industrial Revolution started to question what the strange bones found in their minds and quaries were all about when the first bones were found the idea of Extinction and the age of the Earth were virtually unknown no one understood where the bones could have come from or how old they were but the work of few leading scientists would soon provide an explanation in 1799 French anatomist George kuier began comparing the newly discovered bones to those of living creatures he noted similarities and declared the bones were very old and the animals they came from no longer existed it was radical idea that launched the science of paleontology the study of ancient life in 1818 Oxford Professor William buckin applied kier's ideas to partial skeleton he found in an English Quarry he noted the similarity to Bones of modern reptiles and named this new creature Megalosaurus or great lizard 5 years later English Dr Gideon mantel found huge jaw the teeth resembl those of an iguana so he called the creature Iguanodon as more discoveries came to light english anatomist Richard Owen in 1841 published paper in which he classified these new creatures in single group called dinosaur meaning terrible lizards from then on they would be known as the dinosaurs later Owen would supervis Benjamin Waterhouse Hawkins as he recreated the new discoveries at Crystal Palace they were works of tremendous imagination but were based on limited information and riddled with inaccuracies Megalosaurus was shown as merely scaled up version of generic reptile ambling on four legs now we know it stood upright swift two-legged Predator like T-Rex Iguanodon was also shown as four-legged Behemoth with spike on its nose today we know Iguanodon ran on two legs the horn on its snout was actually defensive Spike protruding from its thumb the sculptures more fanciful than real created an image of dinosaurs as giant lumbering lizards but the creators of the Crystal Palace exhibition did the best they could with the little information they had in the following decade the picture of dinosaurs would begin to change across the Atlantic knowledge of dinosaurs grew with the discovery of more fossils as settlers flooded the American West in the 1870s fossils began turning up in the exposed sediments of the dry and Barren regions called Badlands soon museums in the East sent Prospectors to Wyoming and Montana to hunt dinosaurs they came back with new and far more complete specimens than any found before as the diggers brought in one new kind of dinosaur after another scientists vied to classify and name them the work became an obsession for paleontologist ail Marsh of Yale and Edward Drinker cop of The Academy of Natural Sciences in Philadelphia both were extremely ambitious and both were after the same thing to outdo each other by discovering and identifying the most dinosaurs their bitter competition took many forms in 1868 Marsh pointed out that cop in scientific journal had put the head of the giant sea reptile elasmosaurus on the wrong end mortified by his mistake en raged at Marsh cop tried to buy back all copies of the journal before they reached his peers when new fossil bed was uncovered in 1877 at KOMO Bluff Wyoming both cop and Marsh sent Crews to stake their claim rival Prospectors were said to engage in fist fights even smashing fossils in the opposing camp on One Expedition Marsh hired two Army Scouts as escorts one of them was William Cody better known as Buffalo Bill as thorny as it was the competition between cop Marsh and other dinosaur hunters produced huge Trove of fossils they uncovered many new species producing great leap in our knowledge of dinosaurs soon others would head West to dig up prehistory one of these Pioneers was Barnum Brown of the American Museum of of natural history in New York in 1902 he discovered the bones and teeth of giant carnivore he sent his treasure back to the museum for study so impressive were the bones that director Henry Fairfield Osborne dubbed the frightening new Predator Tyrannosaurus Rex the Tyrant Lizard King beginning in 1897 the public image of the new discoveries was shaped by artist Charles Knight originally hired by cop and Osborne to portray dinosaurs in scientific journals Knight was soon commissioned to paint reconstructions of the beasts for magazines and museums early in his career cop and Osborne asked him to paint and sculpt their dinosaurs as agile and active running jumping and fighting quite change from the Crystal Palace down dinosaurs by the 1920s the idea of dinosaurs as quick and dynamic caught Hollywood's imagination as seen in the Lost World in 1925 the depiction though Loosely based on scientific theory was probably chosen more for its thrilled potential by the 1940s for some unknown reason science had returned to its previous View of dinosaurs as slow moving coldblooded and dimwitted Knight reflected this view in 1942 when he wrote and Illustrated an article for National Geographic magazine he described the dinosaurs as harmless and stupid and showed them lumbering across the landscape dragging their tails or wallowing in swamps soon pop culture would EMB brace that image moronic plotting dinosaurs began turning up around every corner but in the last 20 years our knowledge has soared with bounty of new fossils in the 1960s fresh crop of paleontologists was making new discoveries and reexamining old assumptions what they found LED them to question the notion of dinosaurs as lumbering beasts blazing the path was Brash young paleontologist named Bob Bacher in 1969 he began arguing that although dinosaurs shared some features of slow-moving coldblooded reptiles anatomically they looked more like agile warm-blooded animals nearly 30 years later he continues to find evidence to support his ideas like this trackway in Central Wyoming where herd of dinosaurs once crossed mud flat their tracks are now preserved in stone this is the front paw of great 10 ton brontosaur squashing in and pushing up the mud as it walked no claw print the thumb would be there great big claw held off the ground and behind it the much larger hpaw carrying three times as much weight with three claws one two three all chisel edged facing outwards and there are probably several hundred of these guys all walking the same direction these tracks go 100 yards that way 50 yards that way this was one big herd adults and babies crisc cross saying the trackways of the brosur herd are meat eating dinosaurs some little ones Maybe This Tall roughly the weight of coyote and some taller roughly the weight of big mountain line 3 400 lb what they were doing don't know but some of them were moving pretty fast some of them were going around back the brontosaur herd some cutting in the front probably trying to keep out of the way maybe looking for the small fry stirred up by these this enormous weight of Unstoppable herbivores from the spacing of their prints Bacher has determined the meat eating dinosaur were as fast and agile as mammals there's simple equation that lets you calculate how fast these dinos were going if you know how tall they were and how long the stride was now this meat eater is about as tall as was look at this can barely do that can't walk comfortably with that stride this guy was running he was going about 14 an hour some of the tracks that have been found nearby indic speeds of up to 40 mph in spurts and the average speed of all these meat eaters is 7 an hour that's good clip that's the clip that coyotes and wolves and hunting dogs and hyenas use when they're scaring around looking for food that's Hot Blooded Pace in 1986 Bacher presented his radical ideas to the public in his book The Dinosaur heresies in it he Illustrated his theories with his own drawings showing how the anatomy of the dinosaurs made them faster and more agile than reptiles it was groundbreaking and controversial but slowly won over many of his critics he believes past Notions about dinosaurs are the result of scientists trying to fill in the missing pieces of complex puzzle this is wonderful head this is head of kind of brontosaur this is the head that was on brontosaurus itself in all the big movies King Kong the original lost world 1925 this head is powerful head it's got these huge teeth here for crushing plants and leaves big nostril for hooting pretty big eye to wonderful head and when grew up and the Brontosaurus skeleton in New York this wonderful skeleton from in this head was on it it's wonderful head but it's the wrong head how did early dinosaur experts put the wrong head on the brontosaur when big dinosaurs died their remains were often torn apart by scavengers or scattered by floods add millions of years on shifting Earth and it's easy to see why heads and bodies often went their separate ways so it's very rare to find head and then neck and then torso and tail usually find mixed up parts the first brosaurus didn't have head but there was big head from another Quarry nearby take the body from quarry the head from Quarry put them together made sense they fit pretty good it was dead wrong but as more fossils were discovered scientists realized their mistake and replace brontosaurus heads in their museums Baker's hunting ground is Kom Bluff in Central Wyoming he returns every summer to search for more dinosaur relics he's joined by groups of graduate students hoping to make their Mark in the field they'll likely have little to show after long day in the blistering heat it's the possibilities that drive them on the chance to discover completely new dinosaur or complete skull or skeleton if they're lucky their finds will add to the continuing wealth of fossils that began in the early 1800s as the evidence accumulates new theories are formed old ones discarded from sluggish behemoths to fleet-footed Upright Racers from coldblooded to warm blood blooded dinosaurs continue to Fascinate as our picture of them becomes clear while Bacher was redefining our ideas about the creatures Jack Herer was in his lab solving the most compelling dinosaur mystery of all at egg mountain in Montana Jack her's dinosaur eggs provided an opportunity to test whether dinosaurs were birdlike or reptilian he took his treasure to the Museum of the Rockies in Boseman and devised an experiment the answer to his question was written on the bones of the dinosaur hatchlings if the leg bones were weak the baby dinosaurs would need parental help indicating birdlike Behavior but before measuring the strength of the bones Herer needed to determine which of his specimens were embryos and which were just hatched computer enabled him to visualize the largest embryo that could fit inside the egg any that couldn't fit must have been hatchlings once he identified hatchling leg bone he cut thin cross-section of it from its microscopic structure he could determine if it would have been strong enough to Bear the creatures weight he concluded these baby dinosaurs were too weak to stand on their own they dependent on their parents to care for them bird-like Behavior never heard of in dinosaurs before he appropriately named the new dinosaur measur the good mother lizard with his new knowledge about mayaser Behavior her headed back to egg Mountain after years of digging he concluded that 80 million years ago the surrounding area was giant dinosaur Nursery adult neosaurs must have shuttled back and forth to feed their young it would have been as crowded as the nesting colonies of many seabirds today we know they nested in colonies and some of the nests that we have looks as though the the nests were well 25 about the length of an average adult apart from one another which is similar to birds from his study of nearby sediments Herer believes egg Mountain was once an ancient Island surrounded by Shallow Lake which helped protect the babies from predators dinosaurs may have waited out to the island to lay eggs and tend to their young until they were strong enough to leave through the accumulation of fossils and the shrewd analysis of paleontologists such as Herer and Bacher the uniqueness and diversity of the dinosaurs is becoming Ever Clear they were birdlike without being Birds reptilian without being reptiles the question remains when did these Innovations begin the answer May lie in the Valley of the Moon today 65 million years after the last dinosaurs disappeared their fossilized bones are being Unearthed though the rocks are slow to give up their Treasures scientists have discovered over 330 members of the dinosaur clan on average new type of dinosaur is named every 7 weeks at the foot of the Andes Mountains in Argentina lies rugged Barren landscape known as ishigo in English the Valley of the Moon 230 million years ago this was dense and Shady Forest stalking through it were small but menacing creatures the first known dinosaurs buried here along with their bones is the secret of their dominance isolated in the desolate beauty of the this Barren Argentine landscape team of dinosaur hunters hopes to unlock the mysteries of dinosaur evolution ishi colaso the Valley of the Moon is one of the most productive fossil quaries in the world erosion caused by wind and rain combined with seasonally dry climate have exposed layers of sediment dating back almost 300 million years from central Camp 80 mi from the nearest town the team led by American paleontologist William sill of the University of San Juan in Argentina makes daily expeditions to other parts of this 105,000 acre region Sil has explored this Valley for 25 years it's one of the best places in the world to study the roots of dinosaur evolution and understand what made dinosaurs unique among the other creatures that shared the planet this Valley is just about the only place in the world where you have complete sequence of sediments that have fossils in them and that show the story of the origin of the dinosaurs and that's that's very rare very hard to find descending through one of the Valley's many Camp ions Sil and his colleagues go back millions of years each layer of sediment that surrounds them was laid down at different point in the Earth's history to understand why the dinosaurs Rose to dominance they must go back to sediments some 230 million years old it's the first of three geologic periods in which the dinosaurs lived known as the Triassic it lasted from 248 to 205 million years ago the middle period is the Jurassic from 205 to 144 million years ago it was dominated by the largest known Dinosaurs the sods the last period was the Cretaceous beginning 144 million years ago it gave rise to Tyrannosaurus recks triceratops and velocir Raptor then 65 million years ago the Cretaceous ended and the dinosaurs mysteriously vanished dinosaurs were already becoming the dominant species by the middle of the Triassic to discover the world as it existed when they first appeared sill digs in sediments just before that time the dominant creatures of this earlier period were reptiles that had begun to acquire some features of modern day mammals in the Valley of the Moon one of the most common of these mammal-like reptiles was the codon this is the skull of codon one of the mamalik reptiles very common here Pro possibly an omnivore probably vegetarian when you look at the skull this this is how we find them and it doesn't look like much at first but if you look closely you can see the outline of the eyes here the snout down here and back here the large temporal openings where the muscles that pull the jaw together came up through and here's actually part of the lower jaw sticking up through this opening now these were on the line to mammals they they have some of the characteristics of mammals mammal-like reptiles sprawled low to the ground like reptiles with larger brains and complex teeth like mammals they seem to be well on their way to becoming the dominant animals that mammals are today but then their future was jeopardized to find out how Sil takes his expedition higher up the Eastern Slope at ishigo the Red Cliffs hold sediments from the final years of the Triassic period here mamalik reptile fossils are almost non-existent in their place are the bones of new kind of creature the dinosaur what happened part of the answer comes from one of the earliest dinosaurs found here herrerasaurus dating from 225 million years ago it had all the tools necessary to trounce its Rivals the mammal likee reptiles it was 10t long 500lb metor most remarkable were its legs its unique knee and hip joints allowed it to move on two feet bipedal stance that gave it the agility and speed to surpass pass the low slung memal likee reptiles it also freed up its for limbs he was bipedal so his for limbs were used for grasping raking tearing apart the prey in addition to its large claws the skull and Teeth of herrerasaurus made it formidable Predator the things that make him good dinosaur are these big teeth with serated edges like steak knife and of course the major feature is this secondary jaw joint right here sliding jaw joint that allows the tooth bearing part of the lower jaw to open independently of the rest of the lower jaw that opens from back here this would have increased the gape of the animal by about 30° and allowed him to manipulate prey up front while still holding tight to it from with the rear of the jaw puncture wounds and the skull of herrerasaurus are Battle Scars apparently from fight with one of its own from the size of the tooth marks on his skull here we can see one or two of them puncture wounds there's another puncture wound down here from the size of these it looks like it was the same Critter they may have been fighting over killed prey at the time it was discovered herrerasaurus was the most primitive dinosaur ever found but since it had already developed features similar to later meat eting dinosaurs it couldn't have been the first instead it was believed to have been very early stage in the evolution of carnivorous dinosaurs like Tyrannosaurus Rex the search continued for an even more primitive dinosaur in October 1991 one of Sill's graduate students Ricardo Martinez found one his team uncovered the bones of dinosaur roughly 3 feet long barely the size of dog it was found in sediments 228 million years old practically the dawn of the dinosaur age it was named EO Raptor the dawn stealer since then Sills group has found six more this is skull of eel Raptor tremendously important in the history of dinosaurs because the teeth of this shows that it is carnivorous dinosaur the high narrow skull the large orbits tell us that it was an active predator and one of the the great things that tells us of its possible ancestor of all the carnivorous dinosaurs is this incipient jaw joint the second joint that allows it to manipulate prey and that's major characteristic of all of the later carnivorous dinosaurs but it also contains the Primitive features in the pallet it still has the old primitive teeth so here we have what consider be an ideal ancestor for the later carnivorous dinosaurs living just before herrerasaurus Eoraptor had similar features including bipedal stance and serrated teeth but its sliding jaw joint was much less developed even so Sil believes it was menacing Predator that could overpower the mammal-like reptiles he was fast he was agile and he was probably very vicious judging from Modern crocodiles and birds even you know have you seen rooster or if you can imagine an ostrich who is vicious Predator with big teeth and Claws instead of wings chasing down pig or some other animal across the plains that's probably as close as we can come to visualizing Eoraptor as predator eor Raptor's features were similar to those of herrerasaurus but more primitive double-jointed Jaws serrated teeth and anag stance were too much for the slower bigger brained mammal-like reptiles to compete with by the end of the Triassic period dinosaurs had replaced them as the dominant animals the dinosaurs were faster were more agile and were tremendous Predators at this in this case it's question of being fast or being smart and the smart guys lost sill also discovered that the early me ERS had already developed hollow bones trait shared by modern Birds they were Swift light bipedal killers they cleared the path allowing later dinosaurs to diversify grow exponentially in size and outcompete all other animals on land this image of dinosaurs is fire removed from the picture of them as oversized reptiles first put forward at London's Crystal Palace Park in 1854 science once pigeonhole dinosaurs as reptiles but today we're seeing they shared features with birds and mammals too they also had their own traits unmatched by any living animals our growing knowledge of dinosaur behavior is now making it possible to bring these creatures back alive generations of dinosaur scientists have seen their discoveries transformed into public attractions that bring ancient worlds back to life today's version is theme park being created by Walt Disney imagineering engineers and artists are taking everything we currently know about dinosaurs and making them almost as real as they were 100 million years ago according to science liaison Casey Brena the job still leaves room for interpretation one of the challenges of recreating an extinct species which we only have bones to work with today is interpreting what their body motions skin colors and behavior will be and we find that utilizing of course nature as it exists today and with the new knowledge that probably birds are are related to dinosaurs if they aren't actually dinosaurs has given artists lots of inspiration in how dinosaurs would look how they would act and behave like their counterparts 10050 years ago dinosaur artists mix scientific fact with fiction but today they have more science to work with scientists have found impressions of dinosaur skin but no clues as to color for long time artists picture them dull gray since it's now believed that dinosaurs are related to birds artists feel free to use more vibrant colors Disney's robotic styracosaurus relative of Triceratops has also gained from the new paleontology it was once perceived as lumbering animal with huge head stiffly mounted on its body and front legs splayed to the side like lizards recent studies show that its head was connected with limber ball and socket joint the animal's neck muscles could toss the head in any direction ction though we're getting closer to knowing how dinosaurs lived moved and acted we're still long way from knowing everything about them but we're on the right track 19th century scientists greatly expanded dinosaur science more recently men like Jack Herer and Robert Bacher have done the same in inevitably the discoveries and theories of today will be disputed in the future but one of the new ideas is not likely to change that far from being giant reptiles dinosaurs were among the most complex diverse and successful creatures that ever existed millions of years ago the forest thundered with the footsteps of giant dinosaur they were Unstoppable and dangerous at least to the plants these were the herbivores today dinosaur hunters are using new methods and sheer Ingenuity to uncover the bizarre and clever ways Plante eating dinosaurs fended off attackers and devoured vegetation experts are revealing how some grew to be thear largest animals that ever walked on Earth and how others relied on magnificent and deadly armor as they struggled to protect themselves as scientists Pro deeper they're finding out why these seemingly harmless plant eaters were the most plentiful and diverse of all the dinosaurs big or small they Ruled the Land of the Giants meet Nancy the world's largest touring dinosaur she arches three stories into the air and soon she'll stretch longer than an 18wheeler then she'll be center stage at dinofest International traveling dinosaur exhibition but first road crew must finish unpacking her 250 bones more than half are real discovered in Mongolia by Chinese Expedition the rest are life-size casts from her frame scientists can infer much about how she lived the adaptations and defenses that made her success her great size was her best weapon and most useful attribute 8T ribs once walled in stomach so big that massive amounts of food might spend days inside being converted to energy long legs as thick as tree trunks could carry her crushing weight for Miles with minimal exertion her huge feet were twice the size of an elephants as they pounded the ground they left trail of craters revealing Clues to the way she moved and Where She Went Nancy's one of group of the largest dinosaurs called sorop pods their remains are found in Jurassic and early Cretaceous sediments about 200 to 100 million years old that's when they were the dominant Plante eating dinosaurs sods had variety of features that fell between two extremes on one hand was dioicus it had long tail relatively short front legs and slender pencil-like teeth on the other was Brachiosaurus its front legs were taller tail shorter neck more upright and it had broad spatula like Teeth Nancy was more like Deus found in the middle Cretaceous she was the last of her kind none were mental Giants perched to top the long neck was small skull which encased brain estimated at about one qu the size of cows at the other end was huge tail that could send attackers flying with mere like what were these giant dinosaurs really like how could an animal get so big it's puzzle that challenges scientists while some rely on Cutting Edge technology others seek answers from surprisingly simple experiments at Indiana Purdue University paleontologist Jim farlo uses method to estimate just how much cod's weigh he starts with model of the dinosaur its precise proportions are based on fossil evidence and scaled down he submerges it in container of water and measures how much is displaced that gives him the model's value next knowing the model's scale you can figure out the volume of the actual dinosaur and convert it to weight Faro's calculations show that large sorod might have weighed nearly 60 tons the really biggest sorop pods the ones that would have been at the upper end of the size range you may be talking about animals that would have weighed 10 maybe even 20 times as much as large elephant and that's just something your mind finds hard to comprehend as often happens in science solving one puzzle leads to another so the obvious question is why were they able to get so big when very few land mammals have been able to do the same thing well truth in advertising here don't know if you want the absolute truth but can offer some educated guesses farlo and other scientists believe the sod's era had become greener than the one before it evidence shows that carbon dioxide levels rows since plants use carbon dioxide as food plant life flourished with more food to eat Sor pods could grow to enormous sizes but farlo thinks these plants were lowgrade and nutrient poor how then did sods grow and stay huge on such inferior food to learn more about large Plante eaing animals farlo is visiting Jed fr's Farm in Indiana Jason's up there you want to ride along he'll get the gates for us Jed raises herds of today's most famous plant eaters cows how much of that you with one cow need in day well you know it takes about half bail day per cow is what we kind of figure in the winter time we like to see them have about 25 lbs of hay per cow to get them through the winter every day digesting hay is complicated matter once it's swallowed it's softened in one of the cow's four stomachs microorganisms then break it down even more extracting vitamins then it's regurgitated and chewed again known as chewing the cut sorop pods also had help digesting some scientists believe they swallowed stones called gastroliths like modern birds do the gastrus may have rolled around inside their stomachs or gizzards grinding the vegetation into small digestible bits also according to farlo it takes long time for food to pass through huge animals enormous digestive tract giving microorganisms more time to extract nutrients so sorap pods could digest even the poorest quality plant material like to say the equivalent of shredded newspaper and suspect that sorap pods could get by on that stuff if they were among the best herbivores that have ever lived suspect in their ability to survive on really crummy food sorap pods were built to eat they took full advantage of whatever plant life grew around them but how much food did one of these giants eat well if Jed was feeding sods instead of cows he'd probably need lot more land now Jed was telling me that a,b cow if you were going to pasture it about 10 acres which is about the size of the field that we've got around us here if we want to compare that with what sorod is doing 50 ton sorod that's warm-blooded you're probably looking at something like 270 Acres which is basically little bit farther than as far as you can see from this hill we're on single sorod could consume almost 700 lb of vegetation in day that's if it were warm-blooded but not all scientists are convinced dinosaurs were warm-blooded in fact farlo thinks warm-blooded sorop pods would have devastated plant life so fast nothing would have been left for them to survive on so they must have been coldblooded warm-blooded animals like cows need to keep their internal temperature high by eating lots of food coldblooded animals like lizards rely on the Sun for warmth and eat less if coldblooded sorod would still need to eat almost 250 lounds of plants every day whether warm-blooded or cold sorop pods must have had voracious appetites they amble through forests devouring the scenery with each thunderous step they left trail of Clues ending at their behavior tracks that are now being uncovered millions of years later by new breed of dinosaur expert Flying high in the sky dinosaur expert Christian Mayer has spotted traces of huge dinosaurs in Swiss mountain range known as the Jura the place where the Jurassic period of the age of dinosaurs got its name he's discovered dinosaur trackways here covering an area three times the size of New York City it's called mega track site mayor knows that bones can tell lot about Anatomy but only tracks can reveal clues about the movements of dinosaurs mayor also knows that it takes years of experience to interpret tracks so he's asked track expert Martin lley from the University of Colorado at Denver to help Andy and walked up to that the first order of business for lley mayor and assistant Dorothy hippler is to map the track site using aerial photographs the with these over here for example they examine the photos to establish the pattern and direction of each trackway which holds Clues to the dinosaurs Behavior but sometimes irregularities in the Rock can masquerade as dinosaur tracks some of these look like tracks but they're not so for every good track there's probably at least one bad one so they're probably four or five so far mayor has discovered nearly 15 separate trackways scattered throughout the mega track site but how did they get here in the heart of the Jura mountains the answer lies in layer of rock that formed 150 million years ago in the Jurassic period back then the geography here was very different the continents were just beginning to move apart from the single land mass they had once formed known as Pangia the Jura mountains were level Shoreline of now vanished ocean the Tey sea After Dinosaurs trampled soggy Shoreline sun and wind dried their tracks which hardened like concrete the next rainstorm or flood deposited layer of sediment over the tracks preserving them then 15 million years ago as the land masses continued to shift and Collide the shoreline was pushed upward forming mountains sediment covering the tracks eventually eroded revealing the fossilized prints today Christian mayor and his team of trackers are piecing them back together step by step like the slab is still right that's okay among his most recent discoveries are trackways at quarry near the town of muchier yeah wanted to set the Rope up there where the casting people come but take the old the oldest after the aerial photographs the team must examine the tracks up close so they've pounded repelling bolts into the Rock to pull themselves up studying tracks made by animals millions of years ago is dangerous to Martin lley the risks are worth taking he's after the thrill of the hunt it really is like being Tracker of modern animals it's like following creature that passed by yesterday sometimes you feel it it's much more recent you know time doesn't mean anything you're following Jurassic animal one day or following recent animal the next day clinging to the Rock Martin and Dorothy give each massive footprint individual attention to The Trackers the footprints are snapshots of living breathing creatures and we're used to thinking of dinosaurs as skeletons but these are the evidence of the living animal in motion people have referred to them as motion pictures of dinosaurs so they're very Dynamic type of evidence we can see with the sorod track for instance it had big fleshy foot like an elephant so the first thing we learn is the shape of the feet not the shape of the bones in the foot skeleton that we see in the museum but the actual shape of the feet the prints are scrutinized to identify the kind of dinosaur that made them these Impressions lack fine detail but their round shape and large size up to 3 ft across for the hind prints show that they were made by the Burly footpads of sorod dinosaurs next stride length is measured to figure out how fast the dinosaur was moving the prints of slow moving animal are fairly close together as it accelerates its stride lengthens the distance between the prints and average leg lengths known from skeletons are used to calculate speed mayor has determined that these massive creatures were soering at about 5 mph the average walking speed of an elephant track sites like these have also changed the way we think about sods when their bones first appeared in the 19th century scientists speculated that the creatures they belonged to lived in swamps water must have provided the buoyancy necessary to carry such enormous weight and because it was thought that dinosaurs were related to reptiles some belied they crawled low to the ground dragging their tails like crocodiles or Lizards but trackways have told different story the lack of tail drag Mark shows that the animals walked with their tails in the air the narrow width between each footprint shows they walk with their legs directly beneath their bodies like modern elephants stance that could support their tremendous weight without the help of water yeah me until now mapping dinosaur tracks has been low Tech operation today Christian mayor is testing new method that uses lasers and computers one point the device fires beam of light to small reflector placed in footprint by measuring how long it takes for the beam to return the computer calculat the distance to the footprint it's very simple can do this like this can just put one point on this area yeah and he's calculating immediately the area the surface and surface will appear here I'm looking forward to the results think this will be the depth of each print is also recorded from the data the computer will generate 3D contour map of the site because prints of the same depth were made at the same time mayor will be able to single out an individual trackway from multiple Crossings with the click of mouse the new equipment promises to speed up the process of mapping trackways but for now the dinosaur trackers rely on slower time-proven methods after photographing and measuring the track site better picture of what the giant dinosaurs were doing at the ancient Shoreline is emerging the surface of the wall appears to be trampled over many times it appears that hundreds of sods returned here time and again perhaps to cool themselves or maybe Lush vegetation along the banks provided favorite feeding place as dinosaur trackers follow in the footsteps of giants active roaming dinosaurs seem to come to life elsewhere new discovery is fueling long simmering debate about how some of the smaller dinosaurs got around now this is it these are the bad lands of North Dakota 80 million years ago this region of North America was crisscrossed by rivers and streams lush lowland leading to the edge of an inland sea throughout this land Rome the most exotic of Plante eeding dinosaurs Triceratops they lived from about 100 to 65 million years ago at the end of the final period of the Dinosaurs the cret ious like most other dinosaurs they were smaller than the sods but they were large animals in their own right some grew as big as bus Triceratops was member of family of dinosaurs called ceratopsians creatures armed with variety of sharp horns and large fan-like Shields but beneath all that remarkable armor is heated debate that is simmered since these creatures were first discovered how did they stand it began in 1896 when the first known illustration of ceratopsian skeleton appeared on poster of specimens from Yale's Peabody Museum the creature was shown with its front legs straight underneath in an upright stance like rhinoceros but it was guess fossils from several discoveries were combined because complete skeleton had not yet been found in the same year Triceratop skeleton was mounted by the Smithsonian Museum also composite it was shown in sprawling stance front legs bent crocodile style to many an upright stance implies an agile warm-blooded dinosaur that could charge attackers sprawling stance means an animal that's slower more reptilian and possibly coldblooded with no way to resolve the issue catops have been depicted both ways for years now remarkable Discovery may end the dispute you know they're going to be thick though after that rain yesterday in the summer of 1994 William gska biologist from the University of Alabama and paleontologist David Burnham found fascinating Triceratops in the bad lands of North Dakota gska had spent weeks scouring the land for dinosaur remains then one day as he was coming over Hilltop he noticed what looked like rib bone sticking out of the ground he contacted burnam they put together crew and set up dig site as more and more bones were exposed gska and Burnham realized they had stumbled upon the most complete Triceratop skeleton ever found over millions of years dinosaur skeletons tend to get broken up and the bones scattered over wide area but this skeleton was articulated most of the bones were still connected they named their find Raymond as Raymond emerged gska and Burnham Could See For the First Time The Natural position of the front legs they were straight underneath his body Raymond and all his ceratopsian kin must have had an upright stance had the debate finally been settled it looked that way but Ralph Johnson of the Milwaukee Public Museum has some doubts before Raymond was found he made discovery of his own attach the attach the foot now so that's got to be rotated around on an expedition in 1981 his team found complete shoulder and front leg of torosaurus another ceratopsian okay hang back in the museum he devised an ingenious way to test how the bones fit together he made plastic cast of them which he connected with metal joints to simulate muscles he used elastic straps fixing them where the bones showed evidence of the actual muscle attachments then he hung the 7ot model from scaffolding and tried walking the leg in both sprawling and ight positions if the position worked the bones would stay in their sockets if not the bones would slip out the result surprised him in this kind of traditional reptile sprawl with the front leg everything works the joints all line up the way they should the muscles act on the bones the way they should it works you can actually get this thing to walk forward which is what you wanted to do now if we go into the other idea straight underneath the body but when Johnson tried to walk the leg underneath the body the bone could only move sideways goings not back and forth stomach there's way to get around that when he twisted the bone around to make it move back and forth he found another problem to be going well now you've got the elbow going in the right direction toward the head of the animal but now our dinosaur looks little bit like popey with foot pointing out to the side so this thing is going to be walking like this actually won't be walking at all there's no way biomechanically to get this animal to move forward by putting these legs directly underneath the body according to Johnson's experiment the case was closed ceratopsians must have sprawled like crocodiles but where does that leave Raymond gska and Bam's prize Discovery Raymond's for limb and hind limb are clearly in an upright position this is not what you'd expect from lizard-like posture he's standing on his tippy toes and so that enables him to move at greater speed it's kind of poised like runner in Johnson's version the shoulder blades are pulled back enabling the legs to sprawl but when gska and Burnham covered Raymond they found his shoulder blades much farther forward allowing his legs to be pushed under the body an upright stance Johnson's impressed but not ready to give in yet Raymond's bones await further study once scientists have had chance to thoroughly examine them then the question may be settled Johnson's already confident about the results and I'm glad about Raymond because it's complete leg it even has the bones in the hands we know it's from one individual and now what they can do is actually try to put those legs together to put those bones together and I'm pretty confident that they're going to find that once they try to articulate those bones get the balls and sockets to line up that they're not going to be able to get them underneath the body and you can see here with stance that hints at his behavior Raymond clutches the secret to how his kind lived meanwhile Innovative use of medical technology is revealing how dinosaur 880 million years older may have died stegosaurs were innocent looking dinosaurs that feasted on Jurassic vegetation about 145 million years ago but should the need arise these generally docile creatures had the equipment to defend themselves against predatory dinosaurs plates along its back intimidated enemies by making the stegosaur appear larger than it really was and lethal spikes at the end of powerful tail could fend off the toughest opponents but even though the spikes were as lethal as daggers it seems they could also be point of vulnerability July 1992 at remote location in Colorado an unusual stegosaurus skeleton was uncovered trapped at the bottom of deep Gully lay one of the most complete specimens ever found with most of its Bones still embedded in rock it was prepared for transport out of the canyon it'd be better to leave earlier in the excavation paleontologist Ken Carpenter and his team discovered that the otherwise well-preserved skeleton had deformed tail spike it piqued their curiosity but before they could study it they'd have to get the stegosaur to the lab as the final layer of rock was removed the team faced problem the encased skeleton was too heavy to lift determined to get it out they called in reinforcements US Army helicopter was sent in to airlift The Remains out of the Ravine they could then be taken to the Denver Natural History Museum where Carpenter could give them thorough examination the helicopters are designed to raise 20th century battle tanks lifting the remains of 145 milliony old stegosaur wasn't much different back in the Museum's lab technicians painstakingly remove the Bones from Rock finally Carpenter was ready to perform the autopsy he began by focusing on the disfigured tail Spike didn't quite know what to make of it thought maybe it was due to crushing from the way of the rock that was encasing it mean certainly if we look at this more normal Spike we can see that there's quite bit of difference in the shape as Carpenter studied the Bony Spike he noticed that it showed signs of healing and regrowth indicating that it wasn't damaged after death he also detected small holes on the surface of the bone suggesting disease one possibility was bacterial infection called osteitis if bone has been broken and is left untreated bacteria can invade its marrow the blood producing tissue held within honeycombed structure at the center within days fluid builds up and the bone develops small holes to relieve the pressure eventually the Bone's inner structure is destroyed the infection can spread throughout the body and cause death could this have been the fate of Carpenters stegosaur to find out he would have to look inside the spike but there was problem doing this would require breaking open the rare fossil something he wasn't willing to do do the answer lay inside Kaiser Hospital in Denver Lori mcin one of his lab volunteers work there she suggested using the hospital's CAT scan medical technology developed to harmlessly cut through human tissue and Bone could expose the spikes interior without destroying it want to see if we can see some detail in that area area Okay first they scanned normal Spike the kind found on healthy stegosaurs next the deformed Spike then the scans were compared this represents normal tail Spike you can the dense outer bone represented here the bone marrow is in the center this is the pathologic spike and you can see the dense outer bone but the bone marrow is no longer where it should be in the infected Spike the honeycomb structure of the inner bone is gone clear indication that it was not crushed by Rock but destroyed by bacteria before the creature died now Carpenter can be quite certain the stegosaur suffered from osteomylitis possibly caused by broken tail Spike but how did the dinosaur break its spike in the first place it may have been casualty of war the weapons and armor of stegosaurs are clear to see but dinosaur expert Bob Bacher has drawn some conclusions about the defenses of sarod dinosaurs other than size that aren't quite so obvious he claims to have uncovered The Secret of how the sarod he calls brontosaurus protected itself I'm standing in the unprotected underbelly of brontosaurus right here there's no bone there's no cartilage and above me would be this huge vat of sloshing digestive fluids we had thought that if you bit brontosaurus here you could kill it we thought that if brontosaurus sat down hard on rock back here could injure its abdomen but we were wrong we have just found the first perfect set of brontosaurus belly armor rods of bone up to 3 feet long which were embedded in the belly muscle right up here and these rods of bone have big knobs on them proving there were strong ligaments in the belly muscle this would give brontosaurus the strongest abdomen of any animal that has ever lived if you were meat eater and tried to bite here you'd break your tooth if you're meat eater and jabbed claw in here it would pull out and if you're brontosaurus these belly bones and muscles would keep your great sloshing gut stiff and firm if you wanted to move fast left or right or if you wanted to stand straight up you see with gut protected and stiffened like this brontosaurus could go from all fours to straight up in few seconds but brosaurus was huge so strong belly or not lifting its body off the ground required few fancy tricks with leverage brontosaurus has strange set of balancing organs now the neck was Hollow all the bones were Hollow and here would be the lungs full of air but you get back here and it's all fluid filled gut and then the mother of all rumps these gigantic hip bones and thigh bones surrounded by muscle with its light front end and heavy rear brosaurus was like seesaw the weight on one end tilting its front end up was no problem the animals designed to go up and go up quick why would you want to tilt up well this is Plante eater lived in an environment where the Summers were dry nothing to eat at ground level but there'd still be leaves green leaves on trees tall trees by tilting up quickly you can access foliage that no other Plante eater could get with its massive legs and long neck brontosaurus could reach perhaps 40 ft high but that flexibility came with price this is the front end of brontosaurus and there two problems here they're related number one the body is designed to tilt up that's true how you going to get blood from the heart way up to the head seems impossible problem number two this animal has tiny brain smaller brain than its an ancestors brontosaurus Evolution was dumbing down are the two problems related yeah see brontosaurus would survive better if it could rear up and get those plants the only way to get those plants would be to remove the need for blood to be pumped up to the head how are you going to do that eliminate the brain in this case reducing the brain was adaptive little brains don't need constant flow of blood this is Hightech successful 40,000 pound perhaps but not everyone agrees there's an alternative Theory it goes like this brontosaurus had heart so big it could pump blood up at the velocity of fire hose it could get that blood way up to the head even when the head was held really high but what would happen when the Brontosaurus lowered its head The Rush of Blood would blow the skull off the rest of the skeleton we may never know for sure how much heart brontosaurus had but we do know that its kind were huge and if size was its best defense then perhaps the safest sorod would be the most immense an honor now bestowed on dinosaur uncovered in the rugged Badlands of Argentina below the equator in region of Argentina known as Patagonia lies the small town of Plaza hunal it's tny museum is home to the remains of what could possibly be the largest dinosaur that ever lived with patriotic touch it's been named Argentinosaurus for the past 8 years paleontologist Ral Kura and his team have been assembling the bones of this previously unknown syod from the cret is period but even with the creature still in bits Korea believes the massive bones leave no doubt about its size the back bones of Argentinosaurus were 50 at least 50% longer than any other Vera from any other known sorad around the world the bones of Argentinosaurus were first spotted on remote Ranch outside Plaza hunal in 1988 word got back to Jose Bonaparte head paleontologist at the Argentine Museum of Natural History in Buenos he sent Korea then student on 1,000m journey to inspect the discovery it didn't take long for Korea to appreciate the Bone's importance determined to get this giant creature out of the ground he moved his family to Plaza hunal then arranged job at the little Museum assembled crew and started digging after many months of hard labor he and his crew freed enough bones to begin taking them back to the museum once there the Careful Cleaning of the bones progressed and Korea began to think about the enormous importance of his enormous dinosaur Argentinosaurus it seemed had become the latest in the series of discoveries of the most gigantic dinosaurs it started century ago when dinosaurs were first being Unearthed in the American West rivalry emerged between two great paleontologists Philadelphia's Edward Drinker cop and Gale University's othneil Charles Marsh it quickly became one of the most vicious battles in modern science hostilities intensified in 1877 when huge bone bed was discovered near Kom Bluff Wyoming according to Legend teams sent out by Marsh and cop lied and cheated even destroyed fossils to prevent their Rivals from collecting them for 12 years these destructive Wars raged in the end Marsh's collectors had Unearthed some of the biggest bones ever found among them was nearly complete skeleton Marsh later called brontosaurus at an estimated 75 ft in length and 15 ft tall it stood about as high as one-story building and span the length of about five midsized cars new Gite appeared in 1910 when the Berlin Museum mounted one of the biggest dinosaur excavations of all time in East Africa 500 men labored to dig out 250 tons of dinosaur bones their Greatest Prize was brachiosaurus with height of 40 ft and length of 85 ft it Remains the biggest dinosaur ever assembled in museum it was taller than three-story building and as long as six cars 70 years would pass before bigger dinosaur was discovered in 1979 in Colorado dinosaur was found that was so big it was called Ultrasaurus it stood 9 ft at its shoulders possibly stretching more than 100 ft in length it's likely to have towered four stories high and SP stand as long as seven cars 6 years later from rocky outcrop in New Mexico came the longest dinosaur ever found the Earth Shaker seismosaurus it had horizontal posture but seismosaurus still may have reached height of three-story building with its long whip-like tail it's estimated to have spanned 150 ft nearly the length of N9 car and what about Argentinosaurus how does it compare it could have been nearly 120 ft in length and 60 ft in height five stories high and nearly eight cars long in overall size Korea believes Argentinosaurus to be the biggest dinosaur ever found the bones of Argentinosaurus are representing an animal 100 tons in weight which is equivalent to 20 African elephants all together in the same time in the same body today Korea's team has uncovered all the bones they're likely to find now Korea faces new challenge finding building large enough to house them how long will Argentinosaurus hold its record no one knows for sure but new challenge is already gearing up to take the field dinosaur hunting used to mean digging vast amounts of Earth to find fossils geophysicist Alan Whitten from the University of Oklahoma hopes to change that he's merged firearms and computer technology with geophysical knowledge and come up with method to locate dinosaur bones deep underground Whitten has come to help colleague find the remains of giant sorod from the early Cretaceous about 110 million years ago it might be future record breaker but they need to find more of it to be sure can by the time we get out there here in Southeastern Oklahoma paleontologist Richard selli and his team have already dug out three gigantic neckbones our guess is that this is this bone here is about the seventh bone down in the neck sort of towards the middle of the neck series and it's good deal larger than Brachiosaurus mean this is this is lot bigger than Brachiosaurus which is huge huge animal so this could rival the very biggest of described dinosaurs how yall making out down here but just when saell thought he might be on his way to discovering the biggest dinosaur ever his luck ran out we found this neck and then it just abruptly came to an end and so we're missing the vast majority of this huge huge animal where is it you can't just dig forever it's just not not practical it was time to call in Alan Whitten and his gear first the overlying soil must be scraped away and the ground flattened then Whitten can start looking for more bones he uses huge 8 gauge shotgun mounted on Wheels when fired it sends sound waves into the Earth the vibrations are detected by an assortment of buried microphones sound waves travel more quickly through the dense bone than the sandy soil so they arrive at the microphones first computer analyzes the patterns of waves then reveals the location of the under underground objects with his device Whitten might just be able to tell Celli where to dig next what I'm planning is to run the gun down the tape measure in this Direction all right shooting it every 2 ft and what we'll get is vertical slice an image of vertical slice right below this tape measure is that all right with the array of microphones in place and signaling to the computer Whitten begins his assistant stays with the computer to confirm transmission now what do we have even with help from technology it's hard locating dinosaur bones deep underground but Whitten won't give up so easily he's brought along other devices one of the most promising is ground penetrating radar or GPR it's been used for years in archaeology but now it's being adapted to paleontology instead of sound waves GPR beams radio waves into the Earth radio waves respond to the chemical composition of an object instead of density and the results are easier to read if the waves hit an object underground with chemical composition of bone they'll bounce back to the surface showing up as an isol ated blip on the computer screen despite technological advances sometimes bones are still found by sheer luck Celli found few more while bulldozing the site we just stopped just in the neck of time with bulldozer that came down to like about this level right where we had those bags gone another 3 or 4 in as this would have been hamburger if witten's work proves successful it will prevent close calls like this and revolutionize dinosaur hunting but the use of geophysics in dinosaur exploration is in its early stages and this time the Giant's Bones have proven elusive so the challenge will have to wait with further refinements Whitten is confident that his technology will be wave of the future that will help us see deep into the past the subtle designs of pling dinosur don't yield Clues easily but today's technology has aided in piecing together the adaptations and behaviors that allow them to flourish in world of vicious predators in the end it's the energy and Imagination of men and women that have helped us to better understand these unique dinosaurs and recreated world that was lost millions of years before the first human walked the Earth today the bones of perhaps only 1% of all the dinosaurus species that live have been uncovered imagine what still waiting to be found what has teeth like Stak claws of Steel and his six tons of pure Terror T-Rex the ultimate killing dinosaur this team of diggers has found more T-Rexes than any other as they probe inside its skull they find what's on its mind dinosaur hunters in Argentina have discovered killer that's even bigger than T-Rex but was it as ferocious bone bed in Wyoming revealed FS tender side to the grizzly allosaurs they may have had family values dinosur digging family has Unearthed the baby they call Bambi but watch out this baby bites it's raptor the awful allosaur the nastiest Raptors the most cunning carnivores meet the dinosaurs Killer Elite in the desolate bad lands of South Dakota team of diggers searches for something nearly as precious as Diamonds the bones of Tyrannosaurus Rex everyone's heard of T-Rex but almost nobody has found one despite Century of searching no more than two dozen specimens have ever turned up but this team has found more T-Rexes than anyone else they're from the Black Hills Institute private fossil hunting operation headquartered in Hill City South Dakota since 1990 they've uncovered five T-Rexes including two of the most complete and largest skeletons anyone has ever seen 3 years ago they found the first fragments of T-Rex they nicknamed Duffy this year they're back to recover the rest of this one Mighty meat eater Tyrannosaurs were armed with slashing Claws and jaws bristling with 6-in serrated teeth they belong to group of meat eating dinosaurs called theropods meaning Beast foot common features were two-legged stance and three main toes on their hind feet some were as small as chickens but an adult T-Rex weighed in at 6 tons bit more than modern bull elephant they lived near the end of the dinosaur era the late Cretaceous from 80 to 65 million years ago on T-Rex's Trail is team led by dinosaur Hunter and black hills president Neil Larson now veteran of five T-Rex digs finding Duffy's bones is proving difficult after three seasons only 25% of the skeleton has been Unearthed many of the large leg and backbones are still missing so is much of the head this year Larsson hopes their luck will change well there's number of skull bones that we have not yet found for Duffy we don't know if we found the brain case or the very front part of the of the nose of the torosaurus Rex those would be extremely important to find because it would finish giving Duffy face dinosaur skeletons are rarely found with the bones lying in their proper places next to each other more often scavengers would drag off pieces of the decomposing dinosaur scattering them over the landscape that's what dinosaur hunter Terry Wentz suspects happened here Duffy was scavenged upon and scattered through large area with kind of pocket of Bones down here by where these folks are working and then we found scattered skull bones way off in the distance now what we would like to find is maybe where the animal actually died because most of those bones are the lighter bones we'd like to find the heavy pelvic bones and the leg bones with no way of telling where the rest of Duffy lies or even if it still exists wentz's crew starts by scraping away layers of top soil they watch carefully for any sign of fossils trained eye can tell fossils apart from rock by their distinctive color and texture if the crew spots one they'll start digging by hand it's demanding work soon the team uncovers an exciting fossil but not dinosaur they found the remains of giant sequia tree it testifies to how drastically the parched Badlands have changed since T-Rex's day when they were covered by lush Forest deep in this Forest 68 million years ago Tyrannosaur died scavengers moved in ripping away its Rotting Flesh and scattering its bones eventually the earth covered them up locking them underground for millions of years today rain snow and wind have eroded the ground and the bones lie just beneath the surface waiting for the black kills crew to uncover them again eventually the team spots tooth and then they discovered the very fragment they were hoping to find the bone from Duffy's front jaw this is an important bone because this is the part that held the first four four teeth of the face of Tyrannosaurus Rex it also held the opening for the nostril of the torosaurus Rex but another reason it's so important is because this bone holds the first four teeth of the T-Rex that would bite into its prey this is front of skull tooth what's really neat about this tooth is that the tooth broke off in life and then it kept using it even after it chipped it and didn't even polished the the face of it it probably broke its tooth fighting another torosaurus rex or biting into the bone of another dinosaur digging up Duffy's bones is just the first step now they must be taken back to the Black Hills lab where they'll be cleaned and studied everyone in Hill City South Dakota knows how to find Black Hills Institute locate the sign with burger eating dinosaur and look across the street you'll see Tyrannosaur skull guarding the entrance most of the time Hill city is quiet town but in 1992 it became the center of one of the hottest dinosaur disputes of all time on May 14th dozen FBI agents the National Guard and local police carried out surprise raid they'd come to seize black Hill's most valuable Discovery the largest and most complete T-Rex ever found nicknam sue the government claimed that Pete Larson Neil's brother dug up Sue in 1990 from public land without permission They confiscated the bones and locked them up at the South Dakota School of Mines Larsson denied the charge Hill City residents were up in arms about the government's actions and protested it didn't help Pete Larsen went to trial he was acquitted on the charges related to sue but was handed brief sentence for failing to fill out customs forms concerning imported money in 1997 Sue was turned over to soues for auction and began with bid of $500,000 Black Hills tried to buy her back but with was out bid they couldn't match the record $7.6 million she was sold for fair warning then at 7 million 600,000 up here 7,600 though there's been nothing quite like the battle over sue the hunt for T-Rex has often stirred up controversy and attracted colorful characters men like Barnum Brown who found the very first T-Rex almost century ago he would turn up in the dusty bad land sporting An Elegant raccoon coat and Polished boots they said he could smell fossils in 1902 brown spotted small bit of bone on Montana Hillside The Rock was so tough he had to blast it with dynamite but what he revealed was astonishing the remains of gigantic carnivorous dinosaur at the American Museum of Natural History where Brown worked they unpacked the stupendous fossils and dubbed the new fine Tyrannosaurus Rex the Tyrant Lizard King eventually Brown found another specimen while the museum assembled the first ever skeleton of Tyrannosaurus the legend of the killer T-Rex was born fossils are still shipped in from the field exactly as they were in Brown's day encased in protective coat of burlap and plaster beneath that coat the fossils still lie embedded in fragments of rock freeing them is where the hard work of the Black Hills lab begins it's painstaking job careless preparation could destroy subtle surface details of the bones such as marks of disease or injury so the Institute has developed new technique for eliminating the final layer of rock without damaging the bone it's like gentle form of sand blasting but instead of sand they use baking soda the soda particles are softer than the fossil bone and won't damage it but even with modern techniques it can take team of 20 people year to clean single large dinosaur of the hundreds of bones in complete Tyrannosaur none are more intriguing than the skull the team will spend hours pouring over every nook and cranny trying to get inside T-Rex's head and see what really made it the ultimate killing machine it's 68 million years ago and T-Rex is on the move it's picked up the scent of its prey but is it Mindless marauder or cunning killer though we can't put ourselves Inside the Mind of T-Rex we can get inside its fossilized skull Neil Larson of the Black Hills Institute has studied the brain case and the subtle Clues it reveals about t-rex intelligence this is the inside of the brain of Tyrannosaurus Rex by studying the different nerve endings and looking at the outside of the skull we can see and figure out how large the brain case of the torosaurus Rex is this is cast of brain from juvenile torosaurus Rex an adult t- Rex would have brain about twice this size even though the tyranosaurus Rex had large siiz Brain it was not as large as human's the brain the purpose of the brain was to serve for reflexes so it could hunt so it could fight so it could sleep and figure out if it was hungry and for mating but it did not have the mental capacity that it needed if it was to look at the stars and wonder what was going to happen next it didn't have to appreciate good music all it had to do was survive in world of dinosaurs while T-Rex was no intellectual its brain was larger than any of today's reptiles and it was bigger than almost all other dinosaurs like the Plante eaters at Tracked Down but just how well that brain could perceive the world around it is matter of debate Neil lson thinks T-Rex had Vision that allowed it to home in on its prey torosaurus Rex had large eyes and binocular vision eyes that face forward unlike plant eaters whose eyes were off to the side Tyrannosaurus Rex eyes looked Straight Ahead at what it was after just like that of eagles and like that of the world's greatest Predators humans it could follow its prey and it also had depth perception so it knew exactly what distance the prey was other scientists aren't so sure T-Rex could see in 3d while its eyes did Face Forward its deep snout may have limited the overlap in Vision needed for 3D but one thing no one argues about is the effectiveness of its teeth 60 of them in an average skull and longer and stronger than those of any other dinosaur well we've always heard that the teeth of torosaurus rexs were knife likee or dagger light and strongly serrated well yes they are serrated and the serration are used for cutting through the meat they're round in cross-section they're round in shape so that as the tooth goes through the meat and meets the bone it can punch right into the bone thereby crushing it instead if it was flat breaking off with its large Brain and Bone crushing teeth T-Rex was long thought to be the most fearsome killer that ever lived but new discovery May topple T-Rex from his throne in 1993 in the bad lands of Argentina called Patagonia chance Discovery turned up the remains of predatory dinosaur that may be even bigger than T-Rex it was found by car mechanic and fossil hunter Ruben carolini he lives near the little Frontier Town of Plaza hunal 700 Southwest of Buenos Aris while fossil hunting and his homemade dune buggy one day he stumble across huge bone at first he thought thought it belonged to giant PL eating dinosaur and contacted paleontologist rodulfo Korea at Plaza hun Call's local Museum Korea and colleague inspected the bone and quickly realized it didn't belong to plant eater but to giant carnivore they named The Great Beast Giganotosaurus carolini in honor of its Discoverer this two foot bone comes from the creature's massive lower jaw the complete skull is 6 ft long the longest of any dinosaur ever found and foot longer than T-Rex's in March 1996 less than 2/3 of the creature had been recovered parts of the jaw and tail as well as the front arms and Claws were still buried leaving many questions unresolved So Korea and his crew of five set out on the final lap of their momentous search for the biggest me Eater of all never passing up chance to find more of his Discovery carolini joins the expedition once they arrive at the site and set up their tents the digging can start helping the team is visiting American dinosaur hunter Nate Murphy on the first day Korea's luck is in the crew finds part of the skull called the praxilla bone that holds Giganotosaurus front teeth and forms its snout it's an important find now Korea can piece together the dinosaur's face it's bigger than thought he kind of Jimmy durandy of therapods right big right big nose it's the last missing piece from Giganotosaurus 6ot long skull and face they won't forget in hurry definitely wouldn't have won any beauty contest would have made T-Rex look like prom queen the the nasal bone is would be this in essence to us so we've got we've got this big ugly nasal processes running right down to the the opening of the nose you know just gnarly bumpy stuff and and then these huge teeth hanging out I'll tell you it'd be your worst nightmare this thing is ugly after today Korea Unearthed what remained of Giganotosaurus giving him important new insights into this previously unknown killer Giganotosaurus was at least 3 tons heavier and 3 ft longer than the biggest Tyrannosaur though at glance it looks like T-Rex there are enough differences to suggest they weren't closely related Giganotosaurus had smaller narrower brain its razor sharp teeth were adapted for slashing flesh not crushing bone with its thicker bones and massive tail it may have been more powerful fighter but the two would never have battled face to face though both both come from the Cretaceous Period 144 to 65 million years ago Giganotosaurus lived in the early Part 30 million years before T-Rex's time Giganotosaurus has emerged as truly remarkable Beast grotesque killer even larger than T-Rex but perhaps Korea shouldn't be surprised by his creatures uniqueness dinosaurs unlike any others keep turning up in Argentina the Argentine Museum of Natural History in buos Aris is treasure House of strange and unique species from ancient Patagonia for the past 30 years it has been the home base of Argentina's most celebrated paleontologist Jose Bonaparte in 1985 he excavated the remains of large meat eating dinosaur at about 25 ft in length it was half the size of Giganotosaurus and not as old it lived in the middle Cretaceous Period about 100 million years ago but as Bonaparte quickly realized it was more bizarre than other carnivorous dinosaurs this is the strangest dinosaur we have it was found 10 years ago in Northern Patagonia the Oddity about this dinosaur are these two front horns along with these very carnivorous teeth this dinosaur also had shorter snout than other meat eating dinosaurs it reminded Bonaparte of bull so he named the creature Carnotaurus or carnivorous bull lizard no other meat eater has horns like Carnotaurus Bonaparte thinks they weren't hunting weapons but evolve for sexual display like the antlers of Stags perhaps male Kors locked horns when they competed for females Carnotaurus represents bizarre offshoot of the mediator's family tree but in Argentina it's not just exotic branches that are found the possible roots of the family tree have been discovered here ancestors that would eventually give rise to the most famous killer of all time T-rex dinosaur hunters have long hoped to find traces of the earliest dinosaur creature that would be the common ancestor of all the later dinosaur groups including cluding the giant me eating theropods like T-Rex to hunt for dinosaur Origins they come to ishi guasto the Valley of the Moon the valley is gigantic depression in the foothills of the Andes in Argentina here the ancient land surfaces are stacked one on top of another like pages in book Fierce winds batter the parched cliffsides and Mesa tops slowly eating away the old land surfaces exposing each page of the book and the fossils buried millions of years ago these rocks date from the Triassic period from 245 to 210 million years ago this was the age when the first dinosaurs appeared in the Valley of the Moon Argentine scientists uncovered fossils of one such early dinosaur which they named herrerasaurus the creature was around 10 ft long and must have weighed about 500 lb though primitive it possessed many features seen in the major theropod dinosaurs that followed paleontologist Bill sill of San Juan university has been studying herrerasaurus for 25 years herrerasaurus Primitive carnivorous dinosaur you have the high narrow skull big eyes and notice that all of the strength of the muscles of the jaw were straight over the teeth which meant that all of the muscle power went directly to the teeth and on top of that he had free for liim he was bipedal so his for liims were used for grasping raking tearing apart the prey look at the size of those claws before the time of herrerasaurus most large land animals were low-slung creatures that resembled crocodiles herrerasaurus looked entirely different changes in the structure of its ankles and hips allowed it to walk upright bipedal body plan that was to reappear in all later meat eating dinosaurs the femur that's the leg bone look at that the knee joint and the hip joint allowed him to stand completely vertical which means he was not only bipedal but all of his legs were rotated under the body that means Speed and Agility so this fellow would have been like two-legged tiger going across the plains hunting prey with herrerasaurus the earliest forms of the killer dinosaur's deadly weapons had appeared over millions of years its descendants evolved their own unique killing strategies in Northwestern Montana they found the remains of one such descendant and while they're uncertain of the exact identity it looks like it could be basser Raptor small but chillingly efficient killer the discovery has been made by an unusual dinosaur hunting team family named the linders each summer the linders pack up their camper and drive out to ranch for unique kind of vacation who needs the beach when you have your very own dinosaur Quarry Cliff Linder and his family have no formal training in paleontology but they become skilled at identifying fossils and are meticulous in their field methods Cliff has taught the boys how to dig fossils like professionals after the top soil is removed they uncover bones with ice piics and brushes while applying acetone hardener to fortify them against breakage the work is difficult but there's quite kick in uncovering dinosaur bones that haven't seen the light of day in 80 million years and occasionally like most families they can't resist chance to joke around like the time Wesley found the skeleton of ground squirrel after carefully painting it black he told Dad it was dinosaur bone one day our second boy came to me with this little bone here we looked it over we couldn't identify it and from there we went to the Black Hills Institute and the first guy we showed it to there got big smile on his face and dug out his book and said this is squirrel bone it is it's ground squirrel common gopher painted with magic marker super glued good job of Faking but practical jokes can backfire few days later Wesley uncovered the real bones of small dinosaur we came up to move some overburden and got down little too deep and rolled out dirt CLA and it had the small jaw in there could tell was carnivore after looked at it for while so after found that ran down the hill and found my mom when he first told his mother she didn't believe him she thought he was just playing another joke but soon it was clear that Wesley had found the remains of velociraptor or very close relative even more exciting the bones were tiny this was baby dinosaur it was no more than 3 ft long and 18 in tall about the size of an eagle because the bones were so immature it was hard to be sure of the exact species the linders named it Bambi when the family showed the bones to paleontologist David Burnham he instantly recognized the importance of their discovery pound forp pound this little guy was was dynamite and these bones are so important because the fossil record for small theropods is very rare because the bones are are lightly built and therefore don't usually preserve very well Bambi and its parents are part of group of dinosaurs from the early Cretaceous commonly called Raptors lightly built they probably leaped feet first at prey using their stiff tails for ballots and the retractable toe claw to rip open flesh with single stroke though little is known about their behavior one site revealed five skeletons buried together hinting at frightening idea these quick and deadly dinosaurs may have run and hunted in packs with Bambi we may learn even more about Raptors the linders managed to find 90% of the skeleton making it quite possibly the most complete of its kind ever found the Linder family's Discovery is Raising other questions appropriately they concern dinosaur Family Life how is delicate young Bambi cared for and protected who caught its food provocative answer is emerging from collection of scarred bones found by Sherlock Holmes of dinosaur slothing this is Koo Bluff in Wyoming fossil Gold Mine ever since railroad workers found the first bones here in 1877 today it's the favorite hunting ground of Bob Bacher and his wife constant Bob is the Wildman of dinosaur experts an original thinker whose provocative theories continue to shake up the field now he's reconstructing the family life of carnivorous dinosaurs the work began when Bob opened new site just below The Ridge at KOMO Bluff it turned out to contain curious mixture of Bones from different kinds of large dinosaurs this is nail Quarry named for an antique nail found on the surface most of the time have to say some amateur student found an important site but this is one of the few places can say found this when we started digging in there were fun things there were giant carnivorous dinosaurs meaters some as big as T-Rex but 60 million years earlier well that's kind of interesting for most of that time in the Jurassic period the landscape here was flood plane without any major rivers or streams not the kind of environment where dinosaurs would gather or where their bones would usually survive something else must have brought them to KOMO Bluff but what as Bacher dug into the Quarry the mystery deepened he found the bones of more and more different kinds of dinosaurs both Plante eaters and meat eaters there are four species of giant carnivorous dinosaurs here that's interesting it's rich vwn of mediators but they were victims as we dug the bones of these giant carnivores we found they' had been chewed these were an eater they were eedes and they were they were chewed they were nod tooth marks were clearly visible on the bones so it looked like nail Quarry had been feeding site dinosaur victims had been killed elsewhere dragged back and eaten here another weird thing about this Quarry is they're no small animals at all the smallest animal is baby de blus at 5 tons 10,000 lb that's the smallest animal well whoever dragged the car es here didn't want small small bodies they didn't want little prey they wanted big hunks of meat and Bone and gristle they wanted haunch of brontosaur the shoulders of stegosaur the tail of megalosaur big pieces so who was doing the killing dragging and eating besides the chewing marks there were other Clues scattered among the bones meeting dinosaurs leave calling carts when they chew they had teeth like crocodiles or sharks they'd break off tooth new tooth would grow in they'd break off their teeth where they were chewing their prey their carcasses this is carnivore tooth that's got wear at the tip where the enamal was ground off who was chewing bones scattered among the assortment of bones at nail Quarry Bacher found teeth that belong to just one type of dinosaur and there's only one species of Predator just one one particular species of no one else so that was an allosaur layer weighing almost 2 tons and stretching over 30 ft allosaurs were among the Jurassic most formidable Hunters if Bob is right they killed their victims first then drag them back to nail Quarry but why among the teeth Bacher found were tiny ones like this from the smallest allosaur ever found baby that probably weighed just one lb fresh out of the egg according to Baker that's why allosaurs drag their prey here to feed their helpless infants here is the shoulder blade of brosur and cutting across at our tooth marks left by carnivores who were gnawing away the flesh those are pretty deep that's from medium siiz allosaur maybe 1,000 lbs but here are we little ones those are so small they only match those tiny baby hatchling allosaur so the scene is there's mother and half-grown allosaurs chewing and over at this corner the little baby before bacher's Discovery Nest sites of only plaing dinosaurs had been found together with evidence of Parental care but many paleontologists assumed that carnivorous dinosaurs were solitary Killers who didn't look after their young now Bones from nail Quarry are changing that view even the fiercest dinosaurs it seems became caring parents when they got back home if you're baby lion you're not fed rabbits you're not fed Chipmunks you're fed hunks of zebra your baby lion mother brings you piece of zebra big piece if you were baby alisur right here in this part of Wyoming you wouldn't be fed little chipmunk sign dinosaur and you didn't have to hunt for yourself you just had to wait for mom maybe your aunt maybe dad to drag in the latest two ton hunk of meat and then you could sit right here and gnaw to your little baby allosaur heart's content in his reconstruction of the allosaur feeding site bacher's passion for understanding how dinosaurs behaved is evident all paleontologists ultimately strive in their own way for similar goal to reconstruct the Lost World of dinosaur Behavior with five T-Rexes under their belt the team at Black Hills Institute are in unique position to test ideas about how carnivorous dinosaurs lived and died this is Stan T-Rex discovered in South Dakota in 1992 the second most complete skeleton ever found Stan is world traveler newly returned from tour of Japan while he's on the road Stan looks more like giant erector set than dinosaur that's because he's designed to be taken apart and fit into collection of wooden crates then slotted back together when he reaches his destination each bone is the original fossil Black Hills has used all of its knowledge of T-Rexes to restore and mount Stan and atomically he's probably the most up-to-date version of T-Rex in the world today early reconstructions depicted Tyrannosaurs as portly creatures barely able to support their own weight and dragging their tails on the ground but assembling recent specimens like Stan has revealed how wrong those early views were the mistakes go back to the days of Barnum Brown who found the first T-Rexes in Montana almost century ago when he brought them back to the American Museum in New York no one knew for sure how the bone should be mounted the director Henry Fairfield Osborne did the best he could with the little information then available after considering several Alternatives he finally posed the first tyrannosaur upright with its tail and feet planted on the ground this is the T-Rex that stood in the American Museum until 1990 scaring generations of children and inspiring Hollywood producers The Land Unknown could man have survived in the dinosaur age of Mighty Monsters shudder at history's most ferocious killer Tyrannosaurus Rex but according to Black Hills institute's Neil Larson the museum got it all wrong 80 years ago when scientists mounted the first Tyrannosaurus Rex they mounted it like the like this toy and like they did all toys ever since then they mounted it standing on two legs resting on its tail for balance they couldn't figure out how te T-Rex being bipedal animal could stand on the two legs without falling flat on his face but the more complete Tyrannosaur skeletons Unearthed in the 1990s are helping dinosaur experts rethink T-Rex Anatomy it seems they had no problem balancing on their back legs and didn't drag their tails v-shaped bone straddled the vertebrae and limited the tails up and down motion locked high off the ground it counterbalance the creature's massive head and with that counterbalance he did not fall flat on his face he could stand he could walk he could run at Breakneck speed chasing down his prey with that tail stretched out right behind him and so was born new T-Rex the sprinting killer with top speed of 40 milph according to Larson but could this be just another T-Rex myth could T-Rex really Sprint up to 40 mph as its revised posture suggests to find out you might come to Montana and look up Matt Smith renowned dinosaur sculptor Smith became curious about T-Rex's Mobility when the Museum of the Rockies in Boseman asked him to design and build new T-Rex in 1990 the museum had Unearthed the most complete skeleton known at that time and wanted to show visitors what it would have looked like in the flesh in sculpting this rendition of the T-Rex was very fortunate we were able to lay out all the bones take look at the relationship between the ribs the vertebrae everything to ensure his model was accurate Smith had to measure each part of the creature every bone tooth and Claw then he had to decide how much flesh to put on the bones it wasn't just guesswork although the Tyrannosaur muscles are long gone each has left its mark on the bones the larger the muscle the bigger the scar you need to look at the bones and on the surface of the fossil there's correlation between the force the muscle exerts onto the surface of the bone and the scarring it leaves behind by looking at that you can help identify the placement of the muscle the size and it'll help give you more accurate rendition of the animal with the model fleshed out and complete Smith sent out copies for other dinosaur researchers to study one reached paleontologist Jim farlo of Indiana Purdue University who wanted to use the model to investigate T-Rex's top running speed according to farlo the creature's speed would be limited by its weight so he used the model in water displacement experiment to estimate how much the T-Rex weighed when it was alive his calculations showed that it would have weighed 6 to 8 tons if T-Rex that heavy ran faster than around 20 mph Faro believes the consequences would be fatal you've got an animal really big heavy animal the size of small truck going at this kind of speed in these certain scenarios it can't stop itself what if T-Rex stumbled or tripped while sprinting at high speed the head alone coming down from 15 ft in the air that would be like taking really big watermelon and dropping it from second your third story window mean the impact the deceleration would sort of make it blow up like water balloon next its body would be crushed under its own weight as it crashed to the ground internal bleeding broken bones punctured lungs you know just don't think it likely that the animal would have engaged in that kind of activity even if the leg bones had been capable of supporting it the risk strikes me as just too great not everyone accepts Faro's view but T-Rex running at even 20 mph would be terrifying enough though tripping may have been disastrous for T-Rex it wasn't the only danger large carnivorous dinosaurs faced as scientists scrutinize the bones of meat eaters the truly violent nature of their world is appearing at the Black Hills Institute dinosaur hunter Terry Wentz examined Sue before she was locked away by the FBI he recalls injuries he found in Her Bones well osaurus Rex had very violent hard life mean they fought lot and we can tell that because of the things we found with like Su for instance the tyranosaurus Rex from Faith area when was working on the rib there's one of the ribs had big mass of extra bone growth on it real weird looking it didn't look like rib at all it had just big mass of bone on it extra bone from an injury down way down inside of that injury was piece of Tyrannosaurus rex tooth that rib had been bitten into by another T-Rex and she also had another very interesting injury that was is aounds scientists when they see it that is she had broken leg and Sue survived that injury it actually healed with broken leg Sue could not have hunted for food perhaps mate fed her while she convalesced could fearsome T-Rex also be kind partner maybe but in the end it was another Tyrannosaur that caused Sue death the last injury that Sue had didn't heal she was literally bitten in the back of the head by another T-Rex and it killed her he bit in the back crushed her skull on top and just ripped out the lower jaw it was just ripped right out and you can kind of tell it looked like the Flesh on the front of the jaw actually held it in place but the whole back of the jaw was just ripped right out some meaters mutilated each other perhaps while defending their Turf others were wounded in Pursuit Of Prey Bob Bacher has found evidence that the mightiest Hunters of the Jurassic period the allosaur faced menacing ad advies okay this particular allosaur has wound inflicted in battle with Plante eater it's right here there's deep penetrating wound which went all the way through the bone and produced an open oozing abscess that lasted for months every time this Critter sat down or probably went who made the wound probably the rear end of Stegosaurus where there are massive spikes the crime probably went like this here's an allosaur here's the stegosaur with spikes and whack as the slow work of freeing their secrets from The Rock continues the true lives of the meat eating dinosaurs are coming to light while there's no doubt they were horrifying monsters science scientists are discovering that they were like nearly all creatures that have inhabited Earth they struggled in their own unique ways to survive to feed themselves to care for their young and to protect their kind as more new discoveries are made and more bones interpreted the killer dinosaurs are becoming more fascinating than ever Dinosaurs Ruled the Earth for 150 million years surviving evolving flourishing then mysteriously they vanished to find out why scientists search the void of outer space they comb the hot Sands of the desert and they Plumb the depths of the ocean some believe the answer is locked up in chunks of Amber everywhere they look they're finding compelling clues about why the Earth was once ruled by dinosaurs and then there were none 65 million years ago the world was teaming with Dinosaurs but then an unimaginable disaster happened giant asteroid came screaming toward Earth at 60,000 mph it burst through the atmosphere and smashed into the planet fiery debris was thrown thousands of miles causing death and destruction smoke and dust formed giant Cloud that enveloped the Earth blotting out the sun and drenching the land with lethal acid Rin the planet was plunged into icy Darkness photo synthesis stopped vegetation withered in the Gloom Plante eating dinosaurs starved to death the meaters soon followed in one swift terrible catastrophe the dinosaur's 150 million year reign came to an end it's compelling story and popular notion but is that the way it really happened many scientists believe it's only part of the story they feel that an asteroid impact alone couldn't have caused the extinction of the dinosaurs their quest for hidden lethal Factor behind the extinction has led them to look in the most unlikely places even the bottom of the ocean today research team is heading toward the coast of Mexico on board ques resolution once an oil drilling ship now converted into the world's biggest and most technologically sophisticated floating lab from theater to the south of the University of Rhode Island oceanographer harer sson is taking his team close to the site of the asteroid impact now partially buried Beneath the Sea he's convinced that the only way the blast could have wiped out the dinosaurs was if it struck extremely rare terrain to prove it he's searching for something peculiar in the sediment where it hit something that made the effects of the explosion more deadly to the dinosaur than the impact itself the team will use the ship's massive drill probe to bring up narrow columns or cores of sediment from the ocean floor each core consists of dozens of seabed layers that accumulated gradually over millions of years we're planning to drill at number of sites in the Caribbean where we will recover cores from the sea floor about mile down that will provide us new information about the process of the impact and the environment effects of this great meteor impact aboard are 10 state-of-the-art Laboratories where the scientists will analyze the chemistry of the rocks and sand in the cores layer clay it there's lot of work ahead but when they finish sigurdson May finally have the answer to the dinosaur's demise it's mystery scientists that been trying to figure out ever since dinosaurs were discovered British naturalist Richard Owen coined the word dinosaur in 1842 and also came up with the first theory for why they died out he believed that in the age of dinosaurs there was depletion of oxygen the dinosaurs survived because they were like sluggish reptiles then somehow oxygen levels Rose favoring the faster moving mammals and the dinosaurs went extinct but Owen's theory was little more than guesswork and since Darwin had yet to publish his theory of evolution most of Owen's contemporaries believed in simpler notion that the dinosaurs were wiped out by the biblical flood as science progressed geologists found evidence of numerous great floods and catastrophes in Earth's history floods that the dinosaurs survived at the turn of the century another idea emerged that the dinosaurs like all other extinct creatures Were Meant to die out and give way to more advanced forms throughout the 20th century many theories were bounced back and forth however all had one thing in common with earlier ideas they couldn't be supported by hard evidence then in 1978 in limestone gorge in central Italy geologist named Walter Alvarez made discovery that took the dinosaur's Extinction out of the realm of guesswork Alvarez noticed strange thin dark line of clay between two layers of sediment dating back roughly 65 million years below the unusual Clay is limestone from the Cretaceous period in which the dinosaurs were thriving above it is the tertiary period when all the dinosaurs and many other life forms disappeared from the fossil record because the layer divides these two geologic periods it's known as the KT boundary the sea was changed to because had already been used to describe another geological time period Alvarez brought sample of the thin clay layer back to the lab for analysis there his team discovered something strange it had over 30 times the normal concentration of rare metal called idium stranger still other researchers soon reported the same clay layer at sites around the world always loaded with iridium then with the help of his father Nobel prize-winning physicist and other colleagues Alvarez came up with daring new Theory since iridium is rare on Earth's surface but common in asteroids he deduced that 65 million years ago 6mile wide asteroid slammed into the Earth and vaporized showering the globe with clouds of idium Rich dust and other debris because this phenomenon coincided with the extinction of the Dinosaurs they developed the now well-known scenario for the dinosaur's sudden death by killer asteroid but critics were quick to point out that idium at that level isn't found only in asteroids it's also in the Earth's core so maybe the dust clouds spewed from volcanic eruptions scientists have found evidence of extraordinary lava flows in India that coincide with dinosaur extinction but it's un certain whether the eruptions were vast enough to cause worldwide Extinction meanwhile if Alvarez and his supporters wanted to prove their case they needed to find huge crater somewhere on Earth's surface according to their calculations it should be about 112 mi in diameter and 65 million years old soon several candidates were spot spotted one in Canada another in Iowa but the Canadian crater was too old and neither crater was big enough then in 1990 The elusive crater was finally discovered just off the coast of Mexico's Yucatan Peninsula mostly beneath the Caribbean Sea it was named the chick suub crater though the crater had been found crucial question remained was the impact alone enough to cause the extinction of the dinosaurs and half the life on Earth the team aboard the htis resolution is out to prove that it wasn't their leader harer sson thinks there was more to it his team is here in the Caribbean Sea to explore sediments from the KT boundary that surround the submerged chicku crater they're hoping to find evidence that the rock layers hit by the asteroid were rich in Sulfur which would have worsened the aftermath of the explosion the research ship will drill not into the underwater crater itself but into several spots on its periphery when the asteroid hit it first threw out dense fiery Rock and debris for thousands of miles before the finer particles floated into the atmosphere the heavier ejected material at the KT boundary is what interests girson one of the objectives of our Expedition is to drill into the seafloor in the Caribbean in order to recover material from the boundary layer or from the deposit that was ejected by this great impact the drill team pushes pipe thousands of feet long through hole in the bottom of the ship on the end of the pipe is drill bit with super hard tungsten carbide teeth that can chew through Rock sonar Beacon sends sound waves to the ship guiding the drill into cone already set on the sea Flor to reach mile down they have to assemble the pipe on board linking 100t sections together one by one sand and rock layers beneath the ocean floor get pushed up the pipe to form core that the scientists will study to retrieve just one sample it takes total of 4 hours when they pull the drill back to the surface the core will have the same layers in the same order as the unders Sea Rock itself but the KT boundary layer they're looking for is thin making it extremely difficult to locate beneath mile of water will the team find it there's no way of knowing until they get the core into the lab the team aboard the htis resolution anxiously awaits the retrieval of core containing sediment from the seafloor if it holds the crucial KT boundary layer they'll begin to look for evidence that the killing power of the asteroid that wiped out the dinosaurs was Amplified by its collision with sulfur Rich rocks after the core is recovered and cut into manageable sections it's sliced down the middle at the splitting station half will be saved for later study the other half goes directly to the onboard lab well see what we got here looks like great car now haral or sson and his team can examine the core to see if it contains the dark clay boundary layer the drilling was success this is the the layer is right there in the middle of the core to pin that down well we need to get sample from somewhere down in here we should see it might be in the upper part of this one end is from the courtious period when the dinosaurs were still alive the other end is from the tertiary after they died out and in between is the KT layer that marks the Dinosaurs last days on Earth but sigurdson leaves nothing to chance he has to be sure that he's really found debris thrown from the impact for that he'll study sample under the microscope to look for the unmistakable signs of an asteroid explosion the energy of such blast is so enormous it melts the underlying Rock Globs of liquid rock are flung into the sky the the molten rock cools as it falls to Earth some turns into tiny glass beads or te ties which fall like rain all around the earth at the same time the blast shatters grains of the mineral quartz in distinctive way it's called shocked quartz under the microscope they find the shocked quartz it's clearly sheared and Shattered by the force of the explosion then they find the distinctive glass beads the tech ties the two discoveries prove they pinpointed the ejected material now sigurdson and his team can begin to analyze the te ties for sulfur content careful chemical analysis later shows that sigurdson found what he wanted the tech ties contain high level of sulfur indicating the asteroid Sur sentiment that was rich in mineral called gypsum according to sigon the energy of the impact would have vaporized the gypsum into huge cloud of sulfur dioxide as it spread through the upper atmosphere it changed into sulfuric acid particles of the sulfuric acid acted like trillions of lenses reflecting the sunlight away from the earth the deadly Veil would have blocked out sunlight to greater degree than anyone unimagined for an entire year the world must have been dark and Frozen leaving no chance for the dinosaurs to survive it was an incredible twist of fate that the asteroid hit where it did it was like bomb hitting powder cake even more astonishing less than 1% of the Earth's crust has this kind of sulfur Rich rock if the asteroid had hit almost anywhere else the dinosaurs might have survived in the ship's lab the team finds evidence of the impact's effect on creatures that lived in the sea where apparently even more life was wiped out than on land in the lab on sh University of Rhode Island paleontologist Steven deun put Limestone from the core under microscope if you take look at the Rock that's below the impact layer here you see the skeletons of small animals that floated around in the surface ocean eating phytoplankton this rock is composed almost entirely of their skeletons we have in this picture probably eight or nine different varieties same but just centimeter above the impact layer totally different world appears we see rock that's just got few scattered lonely little individuals here and there this these three dots right here comprise the skeleton of one of the few species that actually survived the impact event before the ocean was filled with all these other varieties after the event nothing left so an ocean teaming with life suddenly became Barren and empty one Cosmic mishap forever changed life on Earth to sigurdson it all adds up to proof that massive asteroid blasted into bed of sulfur Rich sediments and wiped out ancient life on Earth in Flash it's clear that the dinosaurs didn't stand chance in the bitter aftermath of the impact but exactly how close did the asteroid come to destroying all life on Earth clues that reveal the magnitude of the devastation are buried in The Bleak bad lands of North Dakota here summer temperatures reach over 100° in the shade and fierce storms whip up the sand but scientists flock here because of its well-preserved record of the end of the dinosaur age today team is setting out to learn more about that record leading them is Kirk Johnson paleobotanist from the Denver Museum of Natural History he's here to look at the fossil record of plants an asteroid powerful enough to Kill the Dinosaurs would have also destroyed tremendous amount of plant life that way now in the Rocks he has little trouble finding the thin dark clay layer that marks the impact the KT boundary this little thin layer here it's about half an inch thick it's here it's dark gray to Black appears as though it was deposited in less than year looks like it's the Fallout layer from an asteroid impact that occurred in Mexico with the impact layer identified Johnson and his crew search for plant fossils to him they can actually reveal more than dinosaur bones the plants they grew with the last dinosaurs actually tell you lot more about the lake Cretaceous Period than the dinosaurs themselves because plants are much more integral part of the landscape when you walk outside for instance what do you see you don't see lots of animals running around you see vegetation plants trees grass to get clear picture of what happened to the vegetation at the KT boundary the team must find wide sample of plant fossils we have to set the stage we have to build the late Cretaceous world before we destroy it and the destruction of that Lake Cretaceous world is what happened right at the boundary and we're what we're trying to do here is reconstruct the vegetation the landscape the environments of Lake rases understand its climate then what we do is climb up the hill we cross the KT boundary we do the same thing in the early tertiary period And We compare before and after the team first Works in sediments from the late Cretaceous Period the time just before the impact they'll soon find out what kind of landscape the dinosaurs roamed in and what what happened to it after the asteroid hit by finding plant fossils from below the KT boundary layer and comparing them to What's Left above paleobotanist Kirk Johnson and his team hope to discover the destructive power of the asteroid that caused the dinosaur's Extinction as the soft rocks from the late Cretaceous layer are Pride open they reveal variety of fossilized leaves impressions of plants that once provided food and shade for the dinosaurs are exposed for the first time in millions of years most are broadleaf like relatives of avocado cinnamon and Lotus plants all are subtropical species even palm tree turns up this is 66 milliony Old Palm FR so we're looking at fossil that would was tree 66 million years ago and that means that 66 million years ago North Dakota wasn't cold in the winters it was warm in the winters and it was warm in the Summers it was subtropical climate in the final days of the dinosaurs this part of North Dakota was lush forest and the soft Sandstone the fossils are found in tells Johnson that stream once ran through this area the fossils formed when leaves dropped into the stream and were buried by sand over time the stream dried up and Sandy layers slowly turned to rock while minerals entered into the leaves and turned them into fossils what's left millions of years later is record of the once green and steamy landscape the dinosaurs lived in but then the asteroid hit and everything changed after the boundary the plant species diversity plummets it's real Barren Wasteland up there mean it's still forests but the forests have five or six different kinds of plants down here in the Cretaceous 60 or 70 species of plants see okay having collected more than 20,000 fossil leaves from above and below the KT boundary Johnson calculates that 80% % of the plant life here disappeared after the impact proof that the asteroid wiped out not just the dinosaurs but entire ecosystems still mystery remains many small creatures made it through the crisis unlike dinosaurs their fossils appear above the KT boundary we find our crocodiles alligators Turtles snakes lizards and mammals and birds frogs things like that but all small animals and one of the things that all small animals share besides their small body size is they have pretty large populations so there's lot more mice than there are elephants for instance and so that's one of the things that probably made the dinosaurs vulnerable was the fact that they were large animals and as result had probably relatively small population size so does solution simply lie in the large numbers of little animals guaranteeing that some would survive the harsh aftermath of the impact or was there something else going on even today the puzzle of the dinosaur's disappearance remains unsolved scientists still bitterly dispute the cause the asteroid Theory may be popular but many don't accept it by probing further they' found Clues hinting at other agents of death and offer explanations as to why some creatures survived at the Tate Museum in Casper Wyoming one of paleontology most original thinkers Bob Bacher has devised his own Solution by looking at the big picture we dinosaur scientists have KT fixation their conferences about the KT their books about the KT their TV programs about the KT that's bit of mistake because if you want to know why the dinosaurs died at the end of the cret you got to put them in context that wasn't the only ecosystem collapse there were five or 10 or 15 others you've got to study the KT by comparing it to the end of the Jurassic and the end of the Triassic and the end end of the peran and the extinctions that hit animals long after the Cretaceous put the KT in context and then you'll find out who killed T-Rex besides the dinosaurs there have actually been at least five mass extinctions throughout the history of our world in fact Extinction seems to be the rule many scientists agree that 90% of all creatures that have ever lived are now extinct studying these mass extinctions Bacher found that they all had something in common he uses the Jurassic Extinction as an example at the end of the Jurassic this system collapsed the top predators the allosaurs went extinct their prey the brontosaurs were nearly totally exterminated the Plante eeding stegosaurs became very rare in the oceans there were Extinction what did it the pattern of dying is the same you see at the KT boundary the end of the Cretaceous in fact every time there's an Extinction on land it happens the same way the victim profile is the same it's the big active predators and the big active plant eaters who die there would be extinctions after the KT there were extinctions before the Jurassic and all of them have the same modus operand you want to know why the allosaurs went extinct you have to find the serial killer that attacks the land ecosystem what caused the large dinosaurs to die at the end of both periods according to Baker every Extinction has coincided with drop in global sea levels this left land bridges connecting previously isolated continents dinosaurs that were living on single land mass could then easily spread from one continent to another but They Carried with them latent diseases from their own habitats when they came in contact with groups of dinosaurs from new habitats diseases would be transmitted without immunities to new diseases one group would be killed off by an epidemic eventually entire populations would collapse but what about the smaller animals according to Baker it was easy for large dinosaurs to roam long distances across land bridges but difficult for small animals even shallow River could block their progress with the big dinosaurs gone niches opened up for those who hung on in the hills of KOMO Bluff Wyoming baker has found evidence of survivors of the Jurassic Extinction which shows similar pattern to the extinction at the KT boundary the extinction of dinosaurs at the end of the Jurassic was an opportunity for other species if you lived in fresh water if you were turtle or crocodile you enjoyed the event Turtle Evolution speeds up during this Extinction time and if you were something else too you enjoyed the event if you were small and hot blooded and furry if you belong to our class the class Melia your Evolution too took advantage of this opportunity so each time an Extinction occurs opportunities are created for the survivors for another scientist the surviving creatures at the KT boundary provide evidence for another novel theory of the dinosaur's demise he believes they weren't killed by sudden asteroid explosion or disease but by something in the air now we can just gently te every summer paleontologist Keith Rigby of Notre Dame University comes to the bad lands of Montana to hunt for fossils okay what he finds here tells different story of the dinosaurs Extinction 65 million years ago we're looking right here at what some say is the aous tertiary boundary black streak in the hillside right here some say this is where an asteroid hit the earth killed the dinosaurs and everything was wiped out in more or less an afternoon what we're finding out is that it's different than that right there the startling evidence he's found is the product of extensive teamwork his students and volunteers aren't looking for prize Museum specimens instead their goal is to collect thousands of tiny bone fragments and teeth from many creatures these will allow rig to build broad picture of entire animal populations he thinks tracing how these populations changed over time is the best way to study the cause of the extinction it's demanding work every day his diggers shovel out couple of tons of dirt but this is no ordinary dirt it comes from near the KT boundary and contains hundreds of small fossils some of the sacks are filled with sediment taken from below the boundary in the Cretaceous Period and others contain sediment from above in the tertiary each is carefully labeled out of it now the team hauls the bags to nearby Reservoir to the right here the contents of the sacks are emptied into strainers each layer is kept separate cons the other way next it's time to head for the water the water rinses away the sand and clay so that only hard material remains mostly Rock turns up tiny broken up fossil bones and teeth are also revealed back on dry land the rocky debris is picked out leaving only fossils finding these fragments is the hardest part of the work the trick is knowing which are rock and which our fossil it takes Discerning Eye though the fossils aren't much to look at there are lots of them from wide range of ancient animals not only dinosaurs but alligators salamanders Turtles even tiny mammals back in the lab the bones are sorted according to whether they were found in Cretaceous or tertiary layers then they're organized by species this will give rig an indication of which animals survived the KT boundary event and which did not no I'm just putting it up there by tracing the fate of wide variety of animals rig creates kind of snapshot of the entire living world in the Cretaceous and tertiary periods if there was sudden catastrophe it should show up as clean break in the fossil record of many species at the KT boundary but in fact Rigby has found just the opposite his work shows that the dinosaur's Extinction unfolded slowly too slowly for an asteroid to have been the cause and was already underway long long before the asteroid hit what's more rig discovered that the smaller animals that became extinct around the time of the impact did so gradually not in one single Swift moment at the same time other species survived unharmed and most surprising small mammals began to diversify and expand so even though rig accepts that an asteroid hit the Earth 65 million years ago he's convinced that other factors have already set the wheels of Extinction into motion in fact according to rig the entire idea of sudden Extinction as seen in the Rocks is misleading layer marking an Extinction may be less than an inch thick but could represent tens of thousands of years we've seen extinctions in the geologic record time and time again they appear sudden in the geologic record but this is Thousands tens of thousands of years to take to accomplish this sudden geologic event it takes time it appears suddenly in the geologic record but in our frame of reference in our life times it's many generations 10,000 100,000 years condensed to appear in the geologic record as sudden but in reality is quite long period of time but if dinosaur extinction was already underway long before the asteroid hit what caused it Rigby and his colleagues have come up with clever and controversial answer he thinks the solution lies inside chunks of Amber but this is no Jurassic Park he isn't trying to bring back the dinosaurs he wants to figure out why they disappeared Amber is formed from hardened Pine resin protective substance found on the surface of trees the sticky resin flows down the tree trapping bugs dirt even bubbles of air after while it solidifies preserving everything inside in its fossilized form it's called Amber Rigby's team has dug up chunks of Amber preserved inside layers of rock from the Cretaceous the last period of the dinosaurs what they're looking for is Amber chunks that have bubbles trapped inside the bubbles they believe contained the air breathed by dinosaurs millions of years ago the clues that we found so far are incredibly interesting we found that the atmosphere of the last of the dinosaurs is dramatically different than what we have now could the air that dinosaurs breathe be different from today's to find out sends off the chunks of Amber from his dig site to lab in Denver there Gary Landis geochemist from the United States Geological Survey will release the air from the bubbles for the first time in millions of years it's nothing short of phenomenal it's really exciting mean to hold piece of capsule that contains air from 60 70 100 million years ago is phenomenal it's thoroughly thrilling but how can Landis be sure the air inside the bubbles is really that old the ancient air may have leaked out or new air leaked in to show that Amber is airtight Landis devised test first he plac samples of Amber inside nuclear reactor the radiation converts potassium found found naturally in the Amber to the gas argon argon molecules are smaller than oxygen molecules and don't react with Amber so argon would escape from the Amber more easily than oxygen after monitoring the samples over 3 and 1/2 year period Landis found that the Argon did not seep out proving that Amber is leak proof the next step is to release the air to analyze its contents and see what Secrets it tells about the fate of the dinosaurs to do that Landis puts Amber from the Cretaceous inside vacuum chamber the machine slowly cracks and crushes the Amber unlocking the ancient air trapped in the bubbles he then uses mass spectrometer to measure the different elements of the air and identify its components the results show the air breathed by the dinosaurs during the middle Cretaceous was made of the same elements as today's but there was one crucial difference the amount of oxygen was dramatically higher at nearly 35% the air we breathe contains only 21% Oxygen by analyzing air samples ranging from the early Cretaceous to today Landis found that oxygen level have gradually dropped Landis and believe the drop in oxygen levels is what slowly killed off the dinosaurs while sparing other creatures including mammals their Theory includes recent studies that suggest dinosaurs may have lacked diaphragm and relied on their giant chest muscles to flex their rib cages in order to breathe the method was inefficient but in an oxygen-rich environment that wasn't problem as the air became thinner however the dinosaurs began to suffocate they were unable to move as rapidly and unable to chase down and make their kills in food they were less capable of migrating to new pastures for grazing for feed you might even speculate that an animal having difficulty breathing enough to maintain its normal activity would be far less interested even in Sex and reproduction meanwhile small mammals prospered they had muscular diaphragm beneath their lungs that helped them breathe the oxygen depleted air smaller reptiles without diaphragms hung on because of their lower metabolic needs but what caused the oxy oxygen level to drop according to Rigby and Landis in the middle period of dinosaurs the Jurassic earth's land masses were rapidly shifting causing great volcanic eruptions and earthquakes the violent activity pumped large amounts of carbon dioxide into the air which the trees converted to oxygen it was lush oxygen-rich environment in which the dinosaurs thrived then in the Cretaceous land mass movements slowly settled down with fewer eruptions less carbon dioxide was spewed plant life withered and oxygen levels dropped slowly the dinosaurs died out by the time the asteroid hit the damage was already done while the oxygen theory is controversial many paleontologists agree that slow acting complex environmental changes contributed to the dinosaur's demise even so it can't be denied that dinosaur remains vanished from the fossil record at the same place that marks an asteroid impact and evidence continues to mount that links the two events vast craters that Scar the Earth's surface show that debris from space as pummeled our planet more than once scientists to keep an eye on the far reaches of space consider the idea of killer asteroid wreaking havoc on our planet as very real threat even today could the human race become just another statistic on the extinction chart with giant asteroid come flying out of the sky and wipe Humanity from the face of the Earth are we doomed to suffer the same fate as the dinosaurs some scientists are taking the threat seriously at kit PE observatory near Tucson Arizona Jim Scotty is one of the astronomers who run project called spacewatch the team operates telescope that keeps an eye out for asteroids and comets approaching Earth Scotty has seen enough of them to be worried to recognize impending disaster as early as possible he bathes his telescope with liquid nitrogen to minimize distortion the telescope automatically rotates throughout the night constantly scanning the skies for asteroids or comets that might be headed our way the view is recorded by sensitive electronic camera attached to the telescope the images are fed into computer which picks out the fast moving asteroids against the background of stationary stars and planets on our computer screen the slower moving main built asteroids are indicated by flagging them with boxes and numbers indicating where the object is in the current image and was in the previous two images our computer software finds literally hundreds of mainbuilt asteroids every night but we're after the fast-moving asteroids that are potential Earth Crossing asteroids so the spacewatch team gets worried only if the computer tracks rogue asteroid that's been kicked out of the main asteroid belt between Mars and Jupiter and is heading toward Earth they're finding about three month what are the chances we'll get hit in fact meteors commonly known as shooting stars hit us all the time they pieces of space debris smaller than an asteroid but anything up to the size of house will burn up in the atmosphere 100t asteroid strikes about once century that's what blew out meteor crater near Flagstaff Arizona 50,000 years ago as for 6m wide dinosaur killer fortunately scientists think it's rare event maybe once every 100 million years but there's another threat to worry about comets these icy masses don't orbit the Sun in well-defined belt like the asteroids do many swing far out to the edge of the solar system Beyond Pluto they're fast moving so they can appear out of deep space with relatively little warning an object the size of the dinosaur killer something like 10 or 20 km in diameter would be visible to our telescope with our current technology probably for only about year or two astronomers only had 16-month warning when fragments of comet Shoemaker Levy were spotted heading toward Jupiter in July 1994 the telescopes recorded the impacts the biggest was equal to 1 million Megaton bomb leaving an impact site the size of planet Earth what could we do if we only had few months notice of such cataclysmic threat with present technology there's not lot we can do there are plenty of ideas about how to defend ourselves like sending nuclear bomb into space to blow it up but no matter what you do you don't want to blow the asteroid to smithin that's not going to help you because instead you're not going to vaporize the asteroid you're going to make it into Big Rubble pile and it's still going to hit the earth it may take more subtle approach to nudge an asteroid out of the way maybe using microwave beams or solar sales the spacewatch scientists think we should be trying to solve the problem dinosaurs lasted for well over 100 million years and they endured at least one other big impact event but during all that time they never quite got around to building an asteroid deflection system so look what it got them it got them fossilized even if humans had been around at the time of the dinosaurs to develop Star Wars technology we might not have saved them though new evidence strongly suggest that an asteroid was the agent of death the dinosaurs may have already been on the way out endangered by millions of years of global change to which they couldn't adapt fast enough or perhaps they dropped in droves from disease for now the dinosaurs Extinction remains compelling mystery but scientists are learning more about the forces of nature that caused it maybe one day they'll put all the pieces together and in the process gain insight about our own future