"For over a hundred years, we've lived with the image." "A six-ton death machine called Tyrannosaurus Rex." "But today, the real nature of this beast is at the center of a debate." "In the Badlands of Montana, a maverick paleontologist is on the trail of a mystery." "Come with me, we'll go back down to the Cretaceous." "Jack Horner is determined to crack open the secrets of a monster." "Even if that means turning the world of T Rex inside out." "Can you see where we are?" "We have grown up believing that T Rex is a predator and it's just hard to get over that hump." "Jack Horner is on the trail of a 65-million-year-old mystery in search of the real Tyrannosaurus Rex." "In a lost world where nature and nightmare converge, giant creatures rule the Earth and sky." "While their reign spans millions of years, life is measured by the minute." "Survival depends on how big you are, how fast you are and the size of your teeth." "Only one beast is feared by all." "Smart, savage, insatiable." "1 5 feet tall and 40 feet long, T Rex can crush a car in its jaws." "Summer is dinosaur hunting season, and paleontologist Jack Horner is on his way to work." "And what Horner is finding, sets him apart from a hundred years of popular belief." "For years people have gotten the idea that Tyrannosaurus Rex was this big predatory dinosaur." "We see it in the toys and in the movies and in the books that we read." "Tyrannosaurus is always trying to eat everything else in sight." "I think it's an interesting idea." "It's interesting, except scientifically speaking no one's ever challenged the idea that T Rex was a predator." "And in fact, no one ever even had evidence to suggest that it was a predator." "I got together with a group of students and decided to look at T Rex as though no one knew what it had ever done for a living." "We just started looking at the evidence and seeing what the evidence said about T Rex." "And we came up with a whole bunch of characteristics that seemed to be very supportive of T Rex being a scavenger rather than a predator." "And yet, no one likes that idea." "In fact, T Rex the predator has never been more popular." "And the challenge to Jack Horner never so great." "Was T Rex a vicious killing machine?" "Was it the cold-hearted butcher we love to hate?" "Challenging the deadly reputation of T Rex is nothing less than heresy." "Jack Horner has come to look for answers in the fossil remains that lay scattered in the parched landscape of the Hell Creek formation." "As part of an ambitious five-year project," "Horner is working to piece together a comprehensive vision of what life was like at the end of the Cretaceous period." "Dinosaurs existed, there's no question about that." "We have the bones of dinosaurs." "We have their skeletons." "We have their footprints." "We have their skin impressions." "There's an awful lot of stuff we know about them as fact." "But when it comes to figuring out what dinosaurs were like as living creatures how they walked, what color they were" "we don't know." "We are sort of at the mercy of our own imaginations." "And so we are always trying to figure out new things about these animals by finding out what's wrong with our present hypotheses." "Hell Creek, Montana is nature's window into the distant past." "Getting to this part of the word means leaving the paved roads hours behind then traveling where there are no roads at all." "It's June." "Excavations begin on a newly discovered T Rex." "We are now capable of getting into areas where people wouldn't normally go." "And the Tyrannosaurus Rex is a very good example." "It is way out there." "It's about as far away from a road and water as you can get." "After almost 65 million years, the land has eroded back to the time of the cretaceous, revealing the world where Tyrannosaurus Rex lived and died." "Actually, you want to give us some slack, we are almost out of rope." "Okay." "Wait." "Hold on." "Hold on." "Wait." "At the end of the last digging season a few promising bones were found sticking out of the bottom of this hill." "But Winter closed in before the fossils could be freed." "When we first found the site, when we first found the T Rex, there was actually a little sandstone sitting over the top of this." "What we did was we uncovered just a little bit of it and we found both legs, and part of the tail going back into the hill, so they put a winterjacket over the top of it and now they are going to take off a whole bunch of dirt." "Using pick axes, shovels and drills, the team carefully removes the two stories of overburden that entomb the precious remains." "Since Tyrannosaurus Rex was first discovered, only two-dozen skeletons have ever been found." "None with all of its bones." "No one has ever found a complete T Rex, and one of the things that we're missing is a tail and this particular specimen that we're digging up right now looks as though there's a very good chance of" "finding a complete tail." "Just over a century ago, Hell Creek produced the world's very first T Rex." "The skeleton uncovered by fossil collector Barnum Brown was far from complete, but enough bones remained to cobble together a prehistoric nightmare." "It was named Tyrannosaurus Rex, or Tyrant Lizard King." "When Barnum Brown discovered T Rex, it had already been established that dinosaurs were reptiles." "So, when T Rex was put together and mounted in the American Museum, it was built just like the reptilian model they expected it to fit." "They stood it up, put its tail down on the floor, got its head way up in the air." "Made it just look about as mean as it could be." "With claws like meat hooks, a massive jaw bristling with deadly teeth and spare parts borrowed from other dinosaurs," "Brown created the Frankenstein monster of the Cretaceous Age." "How could they know to make this T Rex stand up straight, they were breaking its back, neck and tail?" "Yet for most of the 20th Century," "Tyrannosaurus Rex was seen as the savage, upright predator that Barnum Brown imagined." "It wasn't until recently that scientific advances were reflected a new posture for T Rex." "Still, the popular image of the legendary predator remains." "For Horner, that image was shattered for good in 1990." "An amateur fossil hunter named Kathy Wankel brought a few peculiar looking bones to Jack's Museum of he Rockies in Bozeman, Montana." "The lives of Jack Horner and Tyrannosaurus Rex would never be the same." "It was obvious right away that it was a Tyrannosaurus Rex arm." "The first one ever found." "And I was just..." "I was almost beside myself." "I mean, it was really neat to see." "And the first thing that struck me was how short the ulna and the radius were." "Within weeks, an expedition was dispatched to excavate the world's tenth Tyrannosaurus Rex." "And what they unearthed was the most complete T Rex skeleton ever found." "With over 90% of its bones, the Wankel fossil offered the world the first set of T Rex arms." "Jack wondered why nature would endow an aggressive, bloodthirsty predator with such pint-sized limbs." "When predatory animals fight, they have to be able to jump around." "They tip over, they hit the ground, they jump back up again, they fight some more." "Tyrannosaurus Rex couldn't do that." "The most striking thing about T Rex' arm other than the fact that it's really tiny is the fact that that the proportions are out of whack." "I mean, you've got the upper arm bone the humerus bone, which is pretty long, and the two lower arm bones, the ulna and radius, which are really short." "And you look at your own arm and you'll see that the humerus and ulna and radius are about the same length." "And that gives us good grasping power." "We can do lots of things with that." "But T Rex couldn't do that kind of thing." "When you look at the arm, it's actually longer than it is in real life." "In real life, just this hand basically is sticking out of its body." "The rest of it's all encased in muscle." "So imagine Tyrannosaurus Rex with its tiny little arms." "Can't grab anything." "Can't even put its hands together." "Can't reach its mouth." "Can't do anything but scratch its belly." "And here are people talking about T Rex as being a predator." "An animal weighing 12,000 pounds, having a center of gravity that's 12 feet off the ground," "If it tips over it has no way of catching itself, which it doesn't because of its short arms." "It would die." "It would break its jaws." "Break its ribs." "T Rex is an animal that just really cannot afford to fall down." "Is this the fate of the tyrant lizard king?" "Some believe what ultimately killed T Rex rained down from the heavens 65 million years ago." "An asteroid some six miles wide crashed into the Gulf of Mexico, blasting dust and debris into the upper atmosphere." "Lethal clouds blocked the sun and set in motion the mass extinction of the dinosaurs." "Evidence of that catastrophe is seen today in a thin layer of iridium that covers the globe." "Iridium, an element rare on Earth but common in asteroids, is found in rocks and sediment that are 65 million years old." "For dinosaur hunters, this geological reference point marks the end of the Cretaceous Period." "It's called the K/T Boundary" "So, right here, this dark area right here, this is the K/T Boundary." "This is the end of the dinosaur reign." "So everything below us, we can find dinosaurs in." "Everything above it, there are no dinosaurs." "So as we go up and down in section, paleontology really is just, is like time travel." "But you have to have a very good background in geology to know where you are in time." "Otherwise you are lost in time." "Come with me, we'll go back down to the Cretaceous." "The Cretaceous Period spanned almost 80 million years." "During that time, dinosaurs lived and died at the edge of an enormous sea that flooded most of North America." "As the sea withdrew, mountains formed." "Violent storms and floods deposited layers of rock and sediment, entombing the remains of a lost world." "Over millions of years, wind, water and erosion shaped the canyons and valleys of present-day Hell Creek, teasing to the surface the long buried evidence of prehistoric life." "But finding the hidden clues is a slow and painstaking process, where the struggle takes place one step at a time." "This area that we're walking around in right now has probably never been prospected." "People have probably never been here, actually looking for dinosaurs." "It takes an awful lot of work to find something good." "Because we could walk all through this whole thing and, you know, maybe we'll..." "You know, we found an ostrich vertebrae, two of them, and that's good." "That's good for the amount of time we've been here." "So we're doing okay." "You might say that Jack was destined for dinosaurs." "At age eight he found his first fossil and his childhood passion became a lifelong journey." "While Jack searches for new clues, his team on the other side of the valley continues to chip away the hillside still hoping the T Rex beneath will provide a complete tail." "Even when you find something, it can be under 1 5 feet of rock, and so, you get very excited when you find something, but then you've got to be kind of patient about it," "because it might take you all Summer to actually see it." "As the crew moves slowly down," "Jack returns to the museum to reexamine the evidence of the 65-million-year-old mystery." "The predator-scavenger debate really is very exciting because we can only answer this question by having lots and lots of data, and the data has got to come from the field and it's got to come from the laboratory." "It's got to come from both places." "Once again, the Wankel skeleton is the source for clues to the predator-scavenger controversy." "Tyrannosaurus Rex is the largest meat-eating dinosaur that ever lived in North America." "But the dinosaurs that I think are the good predatory dinosaurs, things like Deinonychus and Velociraptor, and Sauronithelestes and so forth, are all small." "They were small, agile animals, built very different than Tyrannosaurus Rex." "Can researchers determine that any dinosaur was a killer from its skeleton?" "If you look at Sauronitholestes or any of the animals like Velociraptor, they have big arms." "Big, long, grasping arms." "Good, long fingers." "Re-curved claws, big claws for hanging on to things." "They've got a long foot." "They've got slashing claws on the hind feet for actually cutting." "There's no question that they could slice and dice with their claw hands, their hands and their feet." "They also have laterally compressed teeth, very sharp, serrated." "This animal is designed to kill things." "Can an animal's skeleton reflect how fast it could run as well?" "We know that Sauronitholestes was one of the fast-running dinosaurs, and we can tell that because it has a relatively short femur compared to its tibia." "The speed of a bipedal animal can be determined by the ratio between its two leg bones." "A short thigh and a long shin, add up to a fast runner." "Using that formula, Jack measures T Rex's legs to see how fast it was." "When we look at T Rex, T Rex's thighbone is 50 inches long and T Rex's shinbone is only 46 inches long." "So the thighbone is longer than the shinbone, which is the opposite of a fast-running animal." "The fact that T Rex has a longer femur than tibia, and that the dinosaurs we think of as being fast runners don't have that, it's evidence I think we can use to hypothesize that Tyrannosaurus Rex was either a really slow runner orjust a walker." "With legs that weren't designed for speed and arms that were basically useless," "Jack hypothesizes that T Rex wasn't able to kill much of anything." "The evidence keeps pointing Jack in one direction." "T Rex simply didn't have the tools to be a hunter." "We have grown up believing that T Rex is a predator and it's just hard to get over that hump." "You know, sixth graders, fourth graders, I mean, they are adamant." "I mean, they throw things at me." "I mean, they just don't believe it at all." "And yet, I grew up with T Rex being a predator as well." "Now I had little toys." "You know my T Rex always chased everything else around and ate it." "All I've been trying to do is get people to think about doing science objectively, not starting out with a preconceived idea, they can..." "You know, I don't care if T Rex was a predator." "Show me some evidence." "Hell Creek will oblige with one of its oldest secrets and a priceless opportunity." "Midway into the digging season, a breakthrough discovery." "A 68-million-year-old T Rex that stands out from all the rest." "Now Horner and his team will be able to compare T Rexes that lived almost three million years apart." "But first they must free the bones from the rock and clay." "Named G Rex after Greg Wilson, the researcher who discovered it, this is the second T Rex discovered this summer and the oldest T Rex ever found." "With surgical care, the crew removes the age-old sediment." "It's hard to see the bones in the ground." "There's one right here at our feet." "This is the shinbone." "This is the knee end of the shin." "The upper end of the tibia." "Right here is the thighbone." "And here is the knee joint end of the thighbone." "Often times when there's mudstone, bone and the rock is about the same color." "But you can see the shape of the rib here." "One here, another one right here." "One under my foot right here." "Basically what we are looking at here is a partial skeleton of a Tyrannosaurus Rex." "It's probably not a huge adult, but with a length probably about 35 feet." "The specimen died probably out on a flood plain of a river and disarticulated." "Came apart." "Bones scattered around a little bit and it was then covered up by subsequent flood deposits." "The chances of uncovering a perfectly preserved skeleton are almost impossible." "When G.rex died, its body returned to the earth." "Its neck and head are pulled back as rigor mortis sets in." "Skin and muscle rot away." "Only the bones remain." "The spring floods could easily wash away its tiny arms, or break away its skull separating at the neck and carrying it off in one direction or another." "A leg could easily separate as well, as could the vulnerable ends of the tail." "The bones are then buried and compressed under tons of mud that hardens into rock." "What's left is a giant cretaceous jigsaw puzzle scattered in the sediment." "You can't predict what you're going to find." "You just never know." "You could dig and dig and dig and find the same old stuff everybody else found over the years and never come up with a new idea." "Or you might be digging along and come up with something brand new." "Everything we find here, everything we uncover, may or may not be a key." "But that's the neat thing about this whole predator-scavenger debate." "There isn't a single thing that it's going to tell you one way or another." "There's just not a smoking gun." "Every part of T Rex must be examined." "To the trained eye, the half-ton skull of Tyrannosaurus Rex may provide important clues to how it survived." "Here are the teeth, the nose, the eyes, the brain." "Clues to how T Rex survived in a kill-or-be-killed world." "If we look at a cast of the brain, what's really obvious is this very enlarged area at the front." "This is the olfactory lobe and right here, this small little bump right here, that's the optic lobe." "And this little thing right here, that's the optic nerve." "So we can just tell by looking at the brain cast that Tyrannosaurus Rex did not have much of a sense of sight." "It certainly wasn't the kind of animal that could hunt at night and I doubt very much if it could hunt very well in the evening or in the morning." "But we look right here, the olfactory lobe is huge." "So from this we can see that T Rex couldn't see well, but it had a tremendous sense of smell" "Perhaps a nearby hospital can help Horner get an inside look at T Rex's sense of smell." "Running the fossilized braincase of Tyrannosaurus through a C AT scan, gives Jack a new view of prehistoric anatomy." "What we are going to do now is just run through C AT scan slices that go from the opening of its nose back to the back of its brain." "This right here is actually the depression that the olfactory lobes rest in." "And they just keep getting bigger and bigger." "T Rex has a huge olfactory, but it's a huge animal." "And so one of the things that's important to do is make comparisons with modern animals that may or may not have large olfactories." "Today's vulture is one of the world's premier scavengers." "It can smell a meal up to 25 miles away." "Like the T Rex, cross-sections of the vulture's skull and olfactory lobes are equally impressive." "Here we see it right here again." "It starts opening up to a relatively large..." "Getting bigger, a lot bigger." "When the two C AT scans are placed side-by-side," "Jack discovers that T Rex's olfactory is proportionally equal to that of the vulture." "Both are huge." "The lesson from all of this is turkey vultures are scavengers." "And they use their huge olfactory to smell things at long distances." "T Rex has a huge olfactory." "So our working hypothesis is that T Rex used this huge olfactory to sense dead things long distances away," "and it walked to them and, ate them." "Tyrannosaurus Rex sniffing out leftovers?" "Jack believes the evidence leads undeniably in that direction." "65 million years later, dinner is still being served in Hell Creek and camp manager Larry Boychuk knows just what to offer hungry dinosaur hunters." "Some want it rare, some want it alive some want it dead." "So that's the trick now, is to try and please everybody." "So, it's a trick in itself." "Just learning, just learning." "I think it's really important that we use our evidence and state what the evidence says and don't go beyond that." "I think that's good science." "I think it's bad science to say that something may have happened, that it may... that T Rex may have been a predator and a scavenger," "because I don't think there's any evidence for it being a predator." "And until someone comes up with that evidence," "I don't think we should say that." "The best thing that we could say, based on the evidence, is that" "T Rex was 1 00 percent scavenger." "But there's still a lot more evidence to be gathered and the hunting season is never long enough." "At first light, Jack and the G Rex crew are back at work." "Like beacons on a faraway shore, the bones of T Rex guide Jack Horner ever deeper into the lost world of the Cretaceous." "He and his crew save hours of walking to G Rex by cutting across the lake." "The team excavating the first T Rex endures a bumpy drive and an hour hike to their site." "For Jack, time is of the essence." "Montana's summers are short and the harsh Winters make fieldwork impossible." "Using a process that hasn't changed in a hundred years, the specimens are covered in layers of plaster, burlap and paper." ""Jackets" in the dinosaur trade." "If a jacket is too thin, a fossil can shatter in transit." "Make a jacket too thick and you'll need a crane to move it." "With time running out," "Jack heads to the first T Rex site to check on progress there." "Along the way he scours the landscape for evidence." "But false leads are all too common." "There's a lot of things that look like bones that are rocks and a lot of rocks that look like bones." "So it's really important that you know what you're looking for." "The bone usually is brown when it's in the ground." "But then when it weathers for a while it bleaches, so it's white." "And when you look at it real close, you can see the spongy nature to it." "You can actually see what people refer to as the marrow." "There's a much different texture to the bone than there is to the rock." "The orange, the black, brown, these are all rocks." "So when we're walking through the hills, this is all we are looking for." "Places where pieces of bones have weathered out." "Weathered down the hill." "When we find them, we look at this and then we just track it up the hill until hopefully we find where it's coming from." "But unfortunately, that's a lot easier said than done." "But sometimes people get lucky." "A few days earlier, while eating lunch under the shade of this cliff, a crewmember spotted some odd-looking bones sticking out of the rocky wall." "The remains of a third T Rex." "This one is in a fine sandstone." "It's uncrushed." "The bone is you know, dark brown." "It's just beautiful." "So even though it's in a nasty place, it's still very well preserved." "And you know, in a lot of ways, it's kind of fun to dig up something like this that's in kind of a precarious position." "Risking his neck to excavate this T Rex is tempting, but Horner puts the dig on hold until next season." "Jack's plate is already full this Summer." "Across the valley, the first T Rex crew also plasters over the exposed fossil." "Not for transit, but for protection from the elements." "This dinosaur will not be coming out this season." "While removing the overburden, the crew made a startling discovery." "When we got down, the first thing they found was this big old hoof-like toe bone, which is not a Tyrannosaur." "And basically what we have here is just a really old duckbill dinosaur that has bone, a bone texture to it that is identical to a tyrannosauroid." "Mistaken identification is nothing new in paleontology, where progress is made as much from being wrong as from being right." "I think this is great science." "You can't always identify things, but you want to identify things." "And so you do your best to identify it." "And if later you learn that your identification was wrong, it's great, you've falsified your hypothesis." "Now affectionately called X Rex, this duckbill may still prove valuable to the predator-scavenger debate, since it lived at the same time as T Rex and would likely have been something it ate." "There is no doubt that this duckbill dinosaur was a contemporary of the Tyrannosaurus Rex that we are working on across the lake." "And so, T Rex was actually feeding on the carcasses of the duckbill dinosaurs after they died." "When we're trying to figure out what T Rex did for a living, what it ate, the first thing we need to do is go to the source, go to the teeth." "The teeth of Tyrannosaurus Rex are the largest meat-eating dinosaur teeth that we know of anywhere in the world." "Of any, any species of carnivorous dinosaur T Rex has the largest, most massive of all the teeth." "The sheer size of these teeth is the source of both the fascination and the legend of the tyrant lizard king." "Jack wants to take a closer look at the evidence to set the record straight." "What is it that people have thought about T Rex that made it a predator?" "And when I went back and looked at the historical records, the man who named Tyrannosaurus Rex, he was the guy that decided that it was a predator," "I guess because for no particular reason other than it was big and had big teeth." "While T Rex's enormous teeth have continued to intimidate people for over a hundred years, progress has been slow in determining exactly how he might have used them." "But then, a remarkable find." "In 1990, a one-of-a-kind fossil was discovered in Hell Creek with the equivalent of 65-million-year-old fingerprints all over it." "The only way we can really tell what Tyrannosaurus Rex ate is to find something that was actually eaten by a Tyrannosaurus." "This right here is a pretty good example." "This Is the sacrum of a Triceratops." "And this particular sacrum has a bunch of big puncture marks in it and those puncture marks just so happen to be the right size for a T Rex tooth." "So we can actually see that a Tyrannosaurus Rex could actually make the puncture marks that we find in this particular sacrum." "So this particular bone is evidence that Tyrannosaurus Rex ate meat." "It's not however evidence that Tyrannosaurus Rex killed anything." "All we can see here is bite marks on it." "We can see that T Rex was a bone crusher." "We could see that when it ate this animal, the animal was dead." "And we can tell that by the fact that we've got these deep marks in the bottom of the sacrum." "The sacrum is located at the bottom of the spine, encased in gristle." "It's the least accessible bone on a Triceratops' body and by logic, would only have been eaten by T Rex after all the choicer morsels had already been consumed." "The clues to the 65-million-year-old mystery are beginning to add up for Jack." "From T Rex the predator to T Rex the scavenger, smelling its way to dinner and arriving after predators have already been served." "T Rex was the kind of animal that got to a carcass second." "The predators get there first." "They get the meat." "The scavengers get there second and they have to crush bone." "And T Rex being a bone-crusher, probably is getting there second." "The emerging image of the new T Rex is nearly complete." "Filling in the remaining gaps requires getting this year's evidence out of the field and safely back to the lab." "Getting it out is the most important thing." "I mean, you can work all summer, but if you don't get it out, you just had fun is all." "A hundred years ago, using horses and wagons, it took weeks for Barnum Brown to get the plaster-covered remains of the first T Rex out of Hell Creek." "These days it can be done in just an afternoon." "For Jack, a season of backbreaking work hangs in the balance." "This is the oldest T Rex known." "It's found at the bottom of the formation." "There are no T Rexes anywhere that are any older than this." "And so, if we re going to see evolution within Tyrannosaurus Rex, we're going to see arms getting smaller." "If we are going to see leg proportions changing." "If we're going to see the kinds of features that I think are important to a scavenging animal." "We're going to see them first in this thing." "Will the oldest T Rex ever found fuel the fire or end the debate over Tyrannosaurus Rex?" "In museums across the country, dinosaurs are the star attractions." "T Rex gets top billing, sending chills of delight up the spines of young and old." "Beneath the display room floor, the changing face of Tyrannosaurus Rex is slowly being revealed." "In a dark corner of the museum, an amazing one-of-a-kind specimen that has never been seen by the public." "Called Daspletosaurus, it's in the tyrannosaur family and a very close cousin of T Rex." "But what's extraordinary is that this is a juvenile." "Once freed of it's rocky grave, the body features of this youngster may write a new chapter on T Rex." "This juvenile Daspletosaurus is probably the best example of a juvenile tyrannosaur that exists in North America." "So once we get the juvenile out of the rock, we will take it to the hospital and we'll C AT scan it and look at its olfactory." "And we'll look at it at the leg proportions." "We'll look at all the stuff that we would look at if we were to have, if we had a baby T Rex." "While a baby T Rex has yet to be found," "Horner is excited about the newest addition to the museum's vast collection." "G Rex, the oldest T Rex in the world." "The skeleton that we call G.rex is the oldest Tyrannosaurus Rex that's ever been found." "And we are right now hypothesizing that it is 68 million years old, as opposed to all the rest of them that are around 65 million years old." "The age of a fossil is calculated by the depth of its location in the ground." "The Wankel Rex was found close to the top of the Hell Creek formation..." "G Rex was found 300 feet lower." "In earth that is nearly three million years older." "By comparing specific bones belonging to the Wankel with the same bones of G Rex," "Jack can see how Tyrannosaurus Rex evolved over time." "What we learn from measuring the femur and the tibia of the older T Rex is that the femur and the tibia have basically the same length." "Making a comparison to the Wankel T Rex, the Wankel T Rex has a longer femur than tibia." "Now, I think this is a very strong indicator." "As T Rex is evolving, T Rex is losing its ability to run and acquiring an adaptation for long distance walking." "The biggest mouth in the world can't eat what it can't catch." "So why would any predator evolve away from running towards walking, unless it was a scavenger?" "If we envision T Rex as a scavenger, then, then we want to give it some attributes that we would associate with a scavenger." "You know, when we look at hyenas, when we look at turkey vultures or any of the vultures." "They are nasty looking, they're vile looking." "They are just awful looking." "A nasty appearance is key to scavenger survival." "It's their primary bluff in the cutthroat competition for food." "The same rules of engagement applied in the Cretaceous." "When a Tyrannosaurus, scavenging Tyrannosaurus, comes up to a carcass, the first thing it has to do is chase away whatever is eating it." "So if I were going to paint a picture of Tyrannosaurus, it would have a red head." "It would be really gnarly looking." "It would have some pretty gross features on it." "T Rex would have been big, nasty and stinky." "That's my idea of T Rex." "For now, dinosaur-hunting season in Hell Creek is over." "Jack takes advantage of the final moments for some last minute prospecting." "And today he gets lucky, very lucky." "It's the last day of the season." "The last hour of the season." "And after an hour out, we picked up a few cool bones." "They don't look like much, mostly they're just bone fragments." "But what's really neat are these two big pieces." "You can see the suture." "This is where the bones actually fit together." "And this right here is the noggin." "This piece right here, from a Tyrannosaurus Rex skull." "And the fact that they came apart, that they're in two pieces, means that it's a juvenile." "So this is a cool thing." "This is a really cool thing." "This is a piece of a juvenile Tyrannosaurus Rex and the skull is still in the ground." "It's been a record-breaking season in Hell Creek with an amazing eight T Rexes found." "But for now it's time for Jack to call it quits." "The mysteries that remain in the ground outnumber those that have been solved." "But in the savage realm of the dinosaur, the balance of power has shifted." "Scientific fact now challenges the legend of the tyrant lizard king." "The new T Rex really is very different from the old idea." "We now see an animal that can't run fast, that's got short, little arms, can't really catch anything," "and really is this smarter animal that is going in and taking over someone else's kill." "So in order to do that, it has to be a really nasty-looking, vile creature." "And as our image of the king of the dinosaurs continues to evolve, for Jack Horner, only the evidence matters and the secrets that are hidden in the "Valley of the T Rex.""