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By manipulating the genetic pathways of chicken embryos, researchers attempt to reactivate ancestral traits, such as growing teeth, long bony tails, and forearms....
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00:01Dinosaurs. You've probably seen hundreds of them.
00:05You might think you know what they look like.
00:08But almost every dinosaur you've ever seen is a work of fiction.
00:15You turn on the television, it almost feels that we know everything about them.
00:21And that's not really the case.
00:23But now a groundbreaking new exhibition is working with the world's leading dinosaur scientists
00:29to revolutionize the way we see these animals.
00:33We've found using our computer models that a human sprinter would probably be pretty well matched for a muscular Tyrannosaurus.
00:41Scientists are pushing the frontiers of our knowledge in new and surprising ways.
00:46We can say these dark stripes were not red, black or whatever, they were ginger.
00:51That's just amazing.
00:52But we've never even found a complete skeleton of a Tyrannosaurus rex,
00:57the most famous dinosaur.
00:59So how on earth have we worked out so much about animals that lived millions of years ago?
01:05How do we get from an incomplete pile of broken bones to this?
01:11How do you build a dinosaur?
01:34How do you build a limb?
01:37I'm Alice Roberts. I'm an anatomist used to working with human bodies.
01:43I'm sure I'm much more able to build this in my life.
01:44And that's justrand information that I've been interested in.
01:44I know that's a whole bunch of restraints of all sorts of things in such.
01:44it's not hard to put a human skeleton together you only need to look in the mirror to get a
01:49pretty good idea of where the bones go but what do you do when the bones belong to animals that
01:56went extinct millions of years ago we all think that we know what dinosaurs look like we've seen
02:04plenty of them pictures in films and animations even in toy shops
02:09but given that the last of the dinosaurs died out about 65 million years ago none of us has ever
02:17actually seen a living dinosaur so how do we know what they look like and how can we be sure
02:26that we're getting it right
02:33here in crystal palace in south london you can still see the first dinosaur exhibition
02:39that was ever built anywhere in the world the sculptures were unveiled in 1854
02:47it was the start of an obsession that we've never got over but it wasn't long before the science
02:54behind these reconstructions had lost credibility
03:00even by the end of the 19th century our ideas about dinosaurs had changed so much that
03:05these models were already looked upon with scorn this megalosaurus for instance is shown walking
03:13on all four legs but we now know he would have been bipedal he would have stood on just his
03:19hind legs
03:20and his forelegs would have been quite small and lifted right up off the ground
03:26when the first iguanodon was discovered only one thumb bone was found so paleontologists thought it
03:32must have been a horn but iguanodon didn't have a horn it's very easy to walk amongst these massive
03:41models and to laugh at the 19th century idea of what a dinosaur was like we now know so much
03:49more we've
03:50worked out a phenomenal amount about the dinosaurs but how have we done that how do you start to get
03:58close to animals that lived hundreds of millions of years ago
04:14from 19th century london to 21st century los angeles 150 years after the first ever dinosaur exhibition
04:22i want to know how we can be sure that we're now getting it right so i've come to la's
04:29museum of natural
04:30history the museum is undergoing major redevelopment at the moment and at the center of it all is a
04:36multi-million dollar new dinosaur exhibit louise chiape is director of the museum's dinosaur institute
04:44and curator of the new exhibition hello i'm very well nice to meet you likewise he'll be packing the
04:52exhibition with everything we know about dinosaurs from the biggest to the smallest with the latest
04:57science on how they looked moved and interacted so beyond the fact that the exhibition is obviously
05:05about dinosaurs what's the idea behind it it's really how do we know what we know about dinosaurs
05:10so you're not just presenting facts to people you're actually showing how you got to that knowledge
05:14yes how do we translate the evidence that we find in in in the field into scientific knowledge
05:21so can i get a sneak preview sure of course yes our knowledge of dinosaurs has been transformed over
05:29recent years and that means that when it opens luis's exhibition will aim to be the most scientifically
05:35accurate representation of dinosaurs ever the science will be brought to life by a wide and varied cast
05:43of dinosaurs but right now the exhibition hall is a building site we are approaching the centerpiece
05:51of the exhibit a large platform that will support three tyrannosaurus rex what we call a growth series of
05:58tyrannosaurus rex because a complete t-rex skeleton has never been found luis's team will have to
06:06reconstruct the missing bones then he'll have to choose poses that reflect the latest scientific
06:12thinking on how these animals stood and moved and with three t-rexes on a single platform he'll even be
06:20considering how they interacted all this for animals that went extinct 65 million years ago
06:27but dinosaurs weren't all big and scary we're still learning more about some of t-rex's relatives
06:35and luis will also be reconstructing a tiny chicken-sized dinosaur called fruited ends as you come into
06:44the other gallery there's going to be a platform with a very large dinosaur a long neck called
06:51mamankisaurus and a tiny little one the tiny fruited ends the smallest dinosaur in north america
06:59they have to build fruited ends from little more than these fossil remains it's never been
07:04reconstructed before so working out what it looked like is a huge challenge and luis's team will be
07:11doing much more than just piecing bones back together they'll be creating a lifelike model of
07:16the animal which means adding muscles and skin i think when most of us go to an exhibition like this
07:24we don't think about all of the work that's gone into it and an exhibition on this scale requires hundreds
07:30of
07:30people to be working together from scientists to engineers to artists and designers but absolutely
07:38none of it would be possible without the starting point of the hard evidence the fossils themselves
07:44because if we'd never found their bones we wouldn't ever have known that these ancient animals ever existed
08:04louise has come to the south eastern corner of utah today this is wild west country a stop off on
08:12the
08:12way to the grand canyon and its past is equally epic all the rocks you can see around here are
08:20mostly of
08:21uh jurassic age so this is prime um dinosaur country
08:31at the time of the jurassic the dinosaurs were in their prime and this was their home
08:40but it was a very different world
08:45back then this area was a wash with streams and floodplains it was the perfect habitat for the
08:52largest land animals that have ever lived the sauropods long-necked plant-eating dinosaurs
09:05it's just a phenomenal place it's beautiful and it's filled with clues about the ancient life
09:14in a vast desert most of us wouldn't have a hope of finding those clues
09:20but if you know what you're looking for the hint of a different color on the ground
09:26is all it takes let me take a closer look you can see the bones right here and here and
09:34here it's
09:35very difficult to see what exactly they may be they're very thin it was probably worth coming back and
09:43and cleaning this a little bit and taking a closer look at what they may be amazingly less than a
09:50hundred
09:51meters away there are more clues to the past louise's colleague has found the remains of a sauropod
10:00there's a piece of rib here that's going into the ground about about this angle and then
10:07there's a piece of the pubis the hip bone right here and it's almost complete
10:13save for just the very back end which is already starting to weather off
10:17louise has to decide what to do with these finds starting a new dig is a huge undertaking requiring
10:23time and money and he has limited resources we already have two very good sides with long-necked
10:31dinosaurs i'm a little reluctant to you know open another excavation just half a mile away is one of
10:40those sites louise's team began working it a year ago most of the bones are still embedded in the rock
10:46and must be painstakingly excavated louise knows from the layer of rock they're digging that this
10:52dinosaur died 150 million years ago but he doesn't know what species it is and it's potentially a
10:59dinosaur that has never been seen before we are actually collecting in an area that has not been
11:05sample no one has really worked here before the possibility of having a new species is very very
11:12exciting a fossil dig is like a murder scene every piece of evidence about what happened 150 million
11:20years ago has to be salvaged the layout of the entire site will be mapped and the precise location of
11:27every
11:28bone fragment recorded to help piece together the remains the more complete the skeleton the easier
11:35it will be to identify and the greater the likelihood that this dinosaur will be turned into an exhibit
11:42we have high limbs we have forelimbs we have a lot of the tail we have ribs we have many
11:49parts of the
11:50skeleton and now we're starting to uncover the neck i would anticipate that we're going to have to
11:56keep opening the quarry to uncover many other um neck vertebra in and hopefully the skull working out
12:06what species this is won't be possible until the bones are back in l.a but fossils are fragile and
12:12moving them is a risky business ready one two three it has to be 400 pounds at least right if
12:29not more
12:30go slowly the team begin the precarious task of shifting a femur the single heaviest bone in the
12:38dinosaur's body try to keep in a line because if we go on the side it's just going to be
12:44really difficult
12:44that one should go that way because the fossil is so delicate it's been cased in plaster and reinforced
12:51with steel bars when you're handling bones that are heavy and fragile that is definitely not an easy
12:59process if you know you don't have um the right people uh the bones can break it will take many
13:09more months of work to excavate the entire skeleton and get it back to la for analysis good good
13:18but to build an exhibition you don't have to spend months in the desert digging up bones
13:25there are other places to find fossils there are plenty of paleontologists working out in the field
13:36and excavating new fossils naming new species every year but there are also scientists who are combing
13:43through existing collections in dusty storerooms hoping to make new discoveries from bones that were
13:50found decades if not centuries ago i've come to the natural history museum in oxford and i'm here to
14:02meet darren nash he's a paleontologist who looks for new dinosaurs in the back rooms of museums
14:11there are always a huge number of specimens behind the scenes
14:17either because they're incomplete unglamorous or unidentified darren i do love these museum
14:24collections when you come behind the scenes and you suddenly feel that you're surrounded by treasures
14:29and it's amazing to think that there are new discoveries to be made in here as well that's
14:34right in a way there are almost too many specimens for the number of experts out there there's always new
14:38stuff to find in collections you don't necessarily have to go out in the field and look for dinosaurs you
14:42can just rummage through museum drawers you will find something new recently darren and a colleague
14:47did exactly that they came across a bone that had been lying on a museum shelf since victorian times
14:54it may look unremarkable but with several unique features it didn't fit with anything that had been
15:00found before and it was enough for them to describe a new species it must have been really exciting to
15:07name
15:08a whole new species of dinosaur yeah yeah we realized straight away that wow this is something
15:12completely new naming a new species you know not such a big deal it's quite easy to do but finding
15:18there are you think that'd be a kind of once in a lifetime wow i've named a new species of
15:24dinosaur
15:24but no no there's certain huge swathes of the tree of life there's very little work been done really
15:30it's quite easy to find new species we're in a golden age of dinosaur discovery there's about 50 new
15:36species of dinosaurs named every year really about 90 percent of all names dinosaurs have been named
15:42since about 1990 if you were to generate a discovery curve of dinosaurs over time you would have a curve
15:47that's shaped like this and we're currently on the steep upward curve of the graph why do you think
15:52there's such a craze for naming new dinosaurs at the moment regions of the world are being explored more
15:58that haven't been really looked at much beforehand so places like southern south america much of central
16:03asia parts of africa and australia more and more people are going out to those places finding new
16:08dinosaurs and bringing them back and the more we find the more complete our understanding of the world
16:15of the dinosaurs becomes it makes you realize just what a vast body of knowledge we've now amassed about
16:23these extinct animals so that a paleontologist can come along look at a single bone and say this must be
16:30a whole new species and it also makes you wonder how many other dusty unloved specimens are sitting
16:38there on store shelves just waiting to be recognized
16:57back in los angeles luis's team are working on the bones that were dug up in utah the next step
17:05in
17:05turning them into an exhibition is to work out exactly what they are well this is where the fossil
17:12bones end up and here the preparators continue the process of excavation this time using delicate tools
17:19and cleaning away the last of the hard sediment revealing the bone itself it's here in the dino lab
17:26that the dinosaurs really start to come back to life
17:32so luis is this one of the specimens from utah yes it is it looks like it's taking ages to
17:39extract
17:39this from the from the stony matrix that has built up around it well erica has been working on this
17:45bone
17:45for several weeks it will definitely take years for the entire skeleton to be prepared to be cleaned up
17:54do you have an idea at the moment what species of dinosaur this might be from not entirely in
18:00terms of the species but we know it's a camarasaurid
18:06camarasaurids were a family of long-necked dinosaurs we currently know of four different species of them
18:12but luis is hopeful that he might have found a fifth so what features will you be looking at as
18:18the bones are cleaned up to help you refine your identification well you'll be looking at the
18:24shape of the centrum here the configuration of the different uh processes the struts the spines of
18:33the vertebra that are are in general very diagnostic they're very telling you must have to be an amazing
18:40anatomist and you must have to know the anatomy of so many different dinosaurs to be able to work out
18:46what it is you're looking at yes but sometimes it's difficult for example here we have two bones
18:53of one dinosaur can you um figure out what they are well i'm a human anatomist so this is stretching
19:04my
19:04expertise and what does to me to identify dinosaur bones and these ones are not very well preserved i'm
19:10sorry brilliant you know they're fairly kind of flat pieces of bone so i would think maybe this is
19:17part of the skull or the jaw and like anywhere near yes you're absolutely right so what you have
19:23here are two lower jaws of a duck-billed dinosaur oh brilliant so they'd come together in the midline
19:29something they actually come together right the other way brilliant
19:38i know how difficult it can be to piece together an ancient skeleton from fragments but i've only ever
19:44worked with one species humans so i'm really impressed by paleontologists who have to understand
19:52the anatomy of hundreds of different dinosaur species
19:57identifying a dinosaur is just the starting point for unlocking its secrets and getting it ready for
20:02display it will be years before this dinosaur is ready for the public instead the centerpiece of
20:09louise's exhibition will be three t-rex skeletons that have already been excavated and are now ready to be
20:22mounted
20:23they're being put together in a workshop in new jersey resurrecting these awe-inspiring creatures will
20:29require mounting the bones in a way that reflects the latest scientific understanding about posture
20:35movement and behavior but the fossil remains of each of these animals are desperately incomplete
20:44paul's the wisher is in charge of turning the partial distorted skeletons into the most up-to-date
20:50reflection of scientific knowledge okie doke uh we've got another several weeks and i'm just trying to
20:56figure out where everyone's at tommy uh right now we're about 50 to 60 finished everything is articulated
21:05we have to get the new bases built did you get those hands straightened out yeah i think we finally
21:11two days later working closely with louise paul and his team will turn a miniature model of the
21:20three t-rexes into a finished exhibit the science will come alive through a combination of art and
21:28engineering louise came out here several months ago he pretty much shifted things around to the
21:34scenario that's going on here but again we have a little liberty uh because we want to make these
21:39things come to life otherwise they just they just don't uh move and they don't look real fossilized
21:46bones are essentially solid lumps of rock which means that mounting them into a skeleton is an enormous
21:52challenge most of the bones are real which makes them extremely heavy we're estimating that the total
21:58weight of the bones is a little over a ton the femurs probably a good 200 250 pounds piece and
22:06we have
22:06to set those in place with special reading devices heaven forbid one of them falls because it would take
22:14quite a bit of time to get those back together the entire skeleton will be held together using a custom
22:20made steel frame which needs to be strong enough to support the enormous weight of the fossils
22:26this will fit in this will get attached to this other section over here and i'll take one of these
22:33ribs here and i'm not sure exactly which one goes where at this point um this is number five so
22:40it would
22:42lay down right in there that will actually get screwed in at the bottom and just settle itself right
22:49right right in here like many t-rexes this one has been given a nickname thomas he's one of the
22:57best
22:57t-rex specimens ever discovered but is still only 70 percent complete the missing bones will be made by
23:05paul's team based on over 30 partial tyrannosaurus rexes that have been found so far on this particular
23:13rib you can see where the real rib goes together with the artificial rib and this is a section that
23:19we had modeled and you can see how it blends in with the real rib how it's glued and it's
23:27also pinned
23:27on the inside so it doesn't break and these ribs will break like icicles if you pick them up the
23:35wrong
23:35way they'll just crack break right apart but it's not just about hanging the skeleton safely the steel
23:43frame will be a work of art in itself millimeter perfect and subtle enough not to draw attention
23:50away from the dinosaur hon jen is filing down part of the rib armature again this is specifically made
23:59like a piece of jewelry it has to hold a specific piece in a special a special way and he's
24:05at the
24:05point now where he's starting to clean up the welds and it's going to be absolutely gorgeous by time he's
24:10finished the pose in which the dinosaur is hung while being true to science will also involve a degree of
24:19artistic interpretation to really bring the exhibit to life a little bit more of a sine wave in it okay
24:25because it's a little too flat and it's not moving well so myself and kevin have been working on the
24:31tail and i personally don't like the way it looks and now we're going to be actually taking that down
24:36next week and putting a slight bend in that to get it give it a little bit more life but
24:41it's just a
24:42visual movement for instance we might change the toes just a little bit to to give this thing a sneaking
24:48feeling or a pausing feeling but it's it's very very very subtle you might move one toe just
24:55one inch in one direction and that changes how you visualize this whole thing
25:02but putting dinosaurs back together is about more than just reconstructing skeletons
25:08we need to work out how they stood how they moved and even understand the details of their physiology
25:16and that's not something that's easy to get right
25:23for example we used to think that t-rex held its head high with its tail dragging along the ground
25:29we
25:30saw it as a cold-blooded lizard-like creature it wasn't until recently that t-rex became a forward
25:39thrusting aggressor so fast it could apparently outrun a car so how did a t-rex stand and was it
25:48really that quick
25:55paleontologists now have access to an incredible set of clues that can help us understand the posture
26:01and movement of dinosaurs it's a set of clues that can tell us what they might have looked like in
26:07the
26:07flesh a set of clues that can even shed light on how quickly they might have run and a set
26:14of clues that
26:15we all see every day birds are the living descendants of a dinosaur because dinosaurs have living descendants
26:26dinosaurs are not extinct they did not become extinct at the end of the mesozoic era
26:34it's an incredible idea but most experts now believe that today's birds are the direct descendants of ancient dinosaurs
26:44so does that mean birds actually are dinosaurs yes absolutely how can you be sure about that
26:50you have evidence from the skeletal anatomy you have evidence from the shape of the eggs and the
26:59microstructure of the eggshell the discovery of a wealth of feathered dinosaurs animals that are
27:05unquestionably dinosaurs and yet have feathers that look just like the feathers of modern birds
27:12it's a discovery that revolutionizes the way we see dinosaurs even some tyrannosaurs were feathered
27:21but the relationship between birds and dinosaurs can tell us much more than simply what they may have
27:27looked like so does this mean that we can use living birds to help us understand dinosaurs absolutely
27:36you know you have 10 000 living species of birds that are providing you an enormous amount of
27:45information that you can use to understand the biology of the ancient dinosaurs it's quite amazing
27:53but it also makes a certain degree of sense when you really look at them
28:00if we want to learn about how the ancient dinosaurs moved and even how quickly they ran
28:06few animals can tell us more than ostriches
28:14they evolved on an early branch of the avian family tree
28:19and like the dinosaurs they're related to they're large bipedal and flightless
28:26we have some living dinosaurs here to take a look at hello ladies they're all ladies are they yes
28:35yes they're a bit more manageable when they're females dr john hutchinson is based at the royal
28:41veterinary college just outside london he's one of the world's leading experts on dinosaur movement
28:46and louise has been consulting him to make sure his t-rexes reflect the latest theories
28:51can i touch them yeah yeah yeah yeah will they peck me they'll peck at your rings really and they'll
28:58try to take them off if they get a good hold but they're not very strong at pecking
29:02i want to feel your feathers now this might be what a dinosaur felt like to touch that's really soft
29:13and
29:13lovely yeah it's just like a cuddly toy oh i'm streaking dinosaurs yeah get off me
29:21i think they do look like dinosaurs especially when you know that some dinosaurs were actually
29:25feathered they certainly do and those feathers are quite primitive in their structure a lot like
29:30some of the fossil feathers we find the similarities aren't just on the surface we can get a much
29:37better understanding of ancient dinosaurs by looking at the anatomy of their modern relatives in depth
29:43and a local farm has recently had to put down one of its ostriches
29:47as an anatomist i'm very used to dissecting cadavers you know i don't usually wear wellington
29:54boots when i'm dissecting hard to say but this will be the first time that i've ever dissected a bird
29:59or for that matter the descendant of a dinosaur so john talk me through the anatomy that we can
30:06see on the surface that's our heel the ankle joint but birds walk with that clear of the ground just
30:12like their dinosaurian ancestors did and really just two toes and one main one the middle toe
30:18is their dominant toe just like in a dinosaur the third toe is is the major toe of the foot
30:24and there
30:25are other similarities to their ancient relatives i don't know if you can see this but here's the tip
30:33of the wing right here and there's a lovely little claw coming off it yeah so so that's
30:38at the end of one of the digits on on their on their arms on their wings and it's you
30:42know just
30:42there as a relic of their of their ancestors yeah but the real clues about dinosaurs come from
30:48seeing what the relationship is between a bird's muscles and its bones right away we can see some
30:55of the the thigh muscles here you can see this lovely red color beautiful beefy muscle so based
31:03on the sections like this how accurately do you think you can reconstruct the musculature of extinct
31:09dinosaurs you can look at any bone and tell something about the soft tissue anatomy of the animal
31:13from the scars as they're called the muscle scars and ligament and tendon scars on the bones that are
31:19attachment points for all these things that we see here is soft tissue actually if i bring a bone
31:26over we can superimpose these two it's got one big muscle attachment right here and dinosaurs have
31:32a muscle scar just like this it appears in the first bipedal dinosaurs this scar on the outside of
31:38the fibula yeah and is not present in earlier animals so this is another link between dinosaurs and
31:45birds so i must look for that the next time i see you can see that i mean t-rex
31:49will have a huge one
31:50of those it's just a massive scar like this big yeah by estimating the muscle sizes of extinct animals
31:58and inputting them into computer models john is able to get an incredible new insight into how dinosaurs
32:05actually moved it's basically running a simulation the computer's figuring out what is the best way to use
32:12these muscles given what we put in to raise the body up we're not animating it we're not saying
32:18do it this way we're just giving it some basic rules of biology this is what kinds of things you
32:24should be trying to do overall and then it finds the best solution yeah yeah so john you've actually
32:29done work trying to reconstruct how t-rex would have looked how his muscles would have worked how he would
32:36have run what kind of results have you got from that yeah so uh we've found using our computer models
32:41that
32:42human sprinter which can do 25 miles an hour or a little faster would probably be pretty well
32:47matched for a muscular tyrannosaurus or an average human who can run about 15 miles per hour would
32:54probably be a pretty good match for kind of a skinnier version of a t-rex john i've heard some
32:58theories
32:59where t-rex has been put forward as running very fast probably faster than that so so has your work
33:06basically disproved that yeah i think uh it's put a lot of doubt in in that idea that t-rex
33:12could run
33:13like as fast as a racehorse or even faster like so 40 miles an hour something like that i don't
33:19think
33:19you'd need an automobile to outrun a t-rex we'd have a chance of outrunning them running away never going
33:26happen thankfully the work of scientists like john has allowed us to not only refine our ideas about
33:35these extinct animals but has actually transformed our image of them if you think about tyrannosaurus rex
33:41as an example we used to think of him as standing upright like godzilla but now we know that he
33:47couldn't have worked like that we treat him like an engineering problem inform that he's in comparative
33:52anatomy of living animals and now we know that his body was much more horizontal with his tail held
33:58up in the air and our reconstructions are much more robust we're getting as close as we possibly can
34:05to what this long dead animal would have looked like but even working out exactly what an adult t-rex
34:14would have looked like only gives you a snapshot of a moment in time to really understand this animal
34:20we need to know how it changed over the course of its entire life and that's why louise's team are
34:26attempting the first ever reconstruction of a baby t-rex there are some small very tiny segments of the baby
34:34but some of them are so small that you can't match anything up nothing like this has ever been found
34:40before it's much harder to recreate a baby than an adult only a few tiny fragments of a skeleton have
34:49ever
34:49been found paul's colleague tommy is trying to piece together the remains from little more than
34:55dinosaur dust there's not a lot of pieces and it's only for the skull see i mean i've gotten several
35:03little pieces put together these bones had similar color the texture on the surface was pretty close
35:11and a lot of times i'll look at the edge of the bone you'll see this one has a little
35:15white
35:16and a little black a lot of times it's just trying the piece see if it'll fit a lot of
35:23people find it
35:23boring um i don't know it calms me although useful for scientists these fossil remains are far too
35:33limited to bring a baby t-rex to life for an audience
35:39and that's why the entire baby skeleton will be a model its bones made not from fossils but from foam
35:46and resin this is where the artists come in they will produce creatures from their imaginations but
35:53they have to be guided by the science which provides them with a range of possibilities ultimately the
36:00animal that they draw or sculpt will be a blend of science and art the baby t-rex will be
36:10sculpted by
36:10doyle one of louise's artists when you're doing something that's brand new that there is no precedent
36:17for can be a little nerve-wracking and it can be a lot of fun for my baby t-rex
36:24there is no reference
36:25for that so there's a lot of interpretation there with his miniature model of an adult t-rex for
36:32reference along with the growing patterns of close relatives of tyrannosaurs it's possible
36:37to work out the likely proportions of the baby the starting point for the sculpture is a simple
36:43illustration so i'm going to start off t-rex usually an adult skull is a great way to measure because
36:52it's so big but in babies skull is going to be thinner the rule is always that the orbit is
37:01going to
37:02be larger and also when you look at human babies you'll notice that they are about three heads tall
37:10versus an adult human which is anywhere from seven to nine depending on how tall they are
37:17do you find yourself at all looking at other people's reconstructions and thinking oh god they've
37:22got that wrong uh yes there are a bunch of people who are out there who are coming from maybe
37:31film or
37:34special effects or something like that they're doing this kind of work from a less informed background
37:40so i'm very privileged to work with a scientist and that's definitely an asset that i don't dare forget
37:50he's looking nice this little t-rex this little two-year-old but with limited fossil remains the
37:56reconstruction has room for creative license so can you draw me another baby t-rex based on the same
38:04evidence but taking it off in a bit of a different direction let's do the same thing we have our
38:10head
38:11there's a lot of evidence that some of them had feathers and that maybe some of them when they were
38:19young would have had some sort of downy covering that would have left in adulthood so that it would
38:27have been shedded before they were fully grown this little baby's looking extraordinarily bird-like
38:33and has really long legs yeah is this a reasonable interpretation there's nothing that says that it
38:39can't be this way right they're fantastic it's the same creature but they're very different even without
38:45the feathers here the length of the legs it's quite extraordinary in this one and i love the feathers i
38:50mean that just immediately makes it look like a completely different creature it shows you that
38:54there's quite a bit of room for artistic maneuver i think in these yes in these reconstructions definitely
39:01definitely the questions about louise's baby t-rex run even deeper than its appearance with such
39:09limited fossils some scientists have actually questioned whether the bones might belong to a different
39:14species of dinosaur entirely something like a t-rex but much smaller you're presenting a mounted
39:22skeleton of this baby t-rex and this is the first baby t-rex that's been found and and has
39:28been put on
39:29display how can you be sure that it is indeed a t-rex if it's a baby because bones changes
39:35as juveniles
39:37turn into adults you can read the characteristics of the bone tissue and that can tell you if the animal
39:45is a full-grown individual or if it's a baby or a very young individual so we know that perhaps
39:52in
39:52future discoveries may prove that there was another species of tyrannosaur that essentially lived together
40:01with t-rex and that maybe this is a baby of that particular species but at the moment um with
40:08information that we have uh it seems that the most reasonable um hypothesis is to say that this one
40:15represents a baby of a tyrannosaurus rex i think that's actually quite brave to put something like a
40:21baby t-rex in this exhibition as a mounted skeleton because there's nothing to compare it with it is our
40:26responsibility to make sure that people understand that things are not written in stone in our
40:32scientific uh conclusions change as we gather more evidence
40:40back in new jersey the t-rexes are nearly complete and luis has come to inspect them this is phenomenal
40:48you know looks awesome it's just fantastic really fantastic everything you thought it would be better
40:58better better better it's hard to describe but i feel that it's very dynamic you know we brought the
41:07right hand foot over the center line quite a bit yeah i can see that turning and i can see
41:14that
41:14there's a little quite a bit of movement yeah i'm glad that you like it louise i think it's phenomenal
41:26but it's not completely finished
41:31paul and his team need luis's advice on a couple of issues
41:38there are several unknowns and the complete tail has never been found
41:42so uh on the older drawings that we have there's maybe 53 tail vertebra the newer thinking is is
41:49there's close to 43 paleontology mostly is a soft science so the theories change with new evidence that
41:57is found one of the big questions about t-rex is what its surprisingly short arms were used for
42:05they might have been used to hold on to prey or to push the body up from a sitting position
42:09no one knows and that's partly because each arm is anchored to the body by the shoulder blade or
42:15scapula and there's no easy way of telling exactly where that sat with the scapula i've seen they've gone
42:23up uh closer to the the vertebra in the backbone i've also seen where they're lowered almost to the
42:29where the belly is there's uh parts of the front end of the scapula the coracoids and some people
42:35think they go together this much and some people that think they go to this much but that all has
42:39to do with how the how everything hangs in the front end of this and also how the hands were
42:44used
42:45those arms are just about the same size as a human arm the difficulty in placing the scapula on thomas
42:52is compounded by the fact that the bones were distorted over the millions of years that they spent
42:57buried underground they're flattened and they don't really have the curvature that they may have
43:05had when when the animal was alive therefore uh it's really difficult to fit them on the sides of
43:14the rib cage i guess that that's the nature of the beast we're gonna have to find a compromise and
43:20we'll
43:20live with it back in la there are two months to go before the exhibition opens the three t-rexes
43:30are now
43:30installed oh this is a bit different there are dinosaurs here now these guys i recognized yes so
43:42this is your famous thomas can we get up here sure yeah absolutely face to face with a baby t
43:50-rex
43:51with three t-rexes of different ages on one platform it's possible for the first time ever
43:56to get an understanding of the entire life cycle of this legend of the dinosaur kingdom so having a
44:03series of juvenile skeletons like this gives you insights into the way that dinosaurs grew absolutely
44:09the dinosaurs had growth spurts so this animal is estimated to have died at the age of two right
44:17and this one here is estimated to have died at the age of 13. there's you know there's a size
44:23discrepancy here but they're also 11 years apart yet this animal is only four years older than this one
44:35yet is enormously bigger than this one what this is telling you is that between 13 and 17 they were
44:46able to add about 1500 pounds that's what 750 kilograms a year wow and when you see the the two
44:55skeletons close to each other like that you really get a kind of physical impression of that although
45:01thomas towers over the younger t-rexes even he wasn't fully grown but at about 17 years old he was
45:08already 11 meters long and over three tons in weight so this is a juvenile this enormous skeleton this is
45:16an animal that probably died at the age of 17 so rather young so still a teenager you can tell
45:22that
45:23it's a juvenile not only based on the histology on the bone tissue that for which we have um studies
45:30of
45:31it but also because there are many bones that would fuse when the animal was a full-grown that have
45:38not
45:38yet been fused and one of them is here the calcaneum and the astragals are completely unfused and both with
45:46the tibia and it's not just the phenomenal speed at which they grew that louise is shedding light on
45:53the final addition to this platform will be the carcass of another dinosaur the t-rex's dinner it will
45:59give us an insight into how the three t-rexes may have interacted so how realistic do you think it
46:06is
46:07to show three tyrannosaurs coming together like this we have evidence suggesting that this animals
46:16lived in groups it's very reasonable to imagine a scene like this in which you have a juvenile
46:22eating a carcass of a duck-billed dinosaur and other individuals coming and being attracted by the carcass
46:31if there's going to be a skeleton here representing an edmontosaurus a duck-billed
46:35dinosaur being eaten by the t-rex is there actually evidence that they ate this type of dinosaur you
46:42have evidence in the shape of bones of duck-billed like edmontosaurus that have tooth marks essentially
46:51and those marks those scratches on the bone coincide well with the shape of the crowns of the teeth of
46:59tyrannosaurus rex that's quite forensic so you've actually got no marks on a on a duck-billed dinosaur
47:05fantastic but the exhibition isn't only about t-rex in amongst the 20 major mounts will be fruit
47:13adems the smallest dinosaur ever to be found in north america working from his own illustration
47:20doyle has created five fruit adems it's the first time that this dinosaur has ever been reconstructed
47:28this is full grown to scale it's a very small dinosaur and one of the smallest in the world
47:35because the specimen is so fragile and sparse the information that we can gather a lot of it is
47:44inferred or we're guessing that it fits with a group of animals based on
47:49what information we do have we don't have a full skeleton by comparing the size of a forelimb to a
47:57thigh bone it was clear that fruited ends was bipedal and by studying clay's relatives it's possible to
48:03get a good idea of what a complete skeleton would have looked like the real challenge was to turn that
48:09skeleton into a fleshed out animal musculature can be inferred from the bones you can see muscle
48:18attachments every animal has some sort of muscle that pulls the leg back and also something that
48:25supports the leg in front a calf muscle gastronemius or any sort of tendon that will go down to the
48:33feet that that's something that exists on every animal that walks on land with large teeth for
48:39mashing plants and sharper teeth for eating insects and worms we can even tell that fruited ends was an
48:46omnivore but the final piece of the puzzle in recreating this animal is its color and that's
48:53something we can't be sure about if you push things too far you go with polka dots and purple and
49:00pink
49:01your audience simply won't believe it if you draw upon the examples of our living animals we can
49:08actually gain a lot just by looking at crocodile skin and coloration and maybe uh some lizards and fish
49:17even and it will remain believable like everything in the exhibition the finished work will have to be
49:23approved by luis so one thing we need to keep in mind is that although we want to have some
49:29variation in
49:32in pattern or in color um they obviously you all need to look same species you're going to give me
49:40some freedom to experiment with some colors maybe in the face or the throat i still think that overall
49:46we want to stick to standard gray green brown i think that it'll be nice to be subtle but something
49:52that can be can be viewed when you're looking at it from you know six feet away although the color
50:00of
50:01fruitidens is unknown new scientific breakthroughs are allowing paleontologists to see some dinosaurs
50:08in a way that's never been possible before
50:19we're still learning more about dinosaurs as increasing numbers of specimens come to light but
50:24also as the techniques that we use to analyze them become more and more sophisticated and i'm off to
50:30meet somebody now who's made great discoveries and one particular aspect of dinosaur science that
50:36many people thought would remain hidden forever okay so here's another one we're going to look at
50:44i'll just put it in it'll take a minute or two to fire up the vacuum professor mike benton recently
50:50came
50:51across the remains of a dinosaur that was so exquisitely well preserved that feathers as well as bones had
50:57fossilized incredibly those feathers can tell us the color of a dinosaur that lived 125 million years ago
51:06going back say 10 years ago would you ever have imagined that you would have been able to tell
51:11what color any dinosaurs would have been no i mean i think at that time i and everybody else would
51:17have
51:17said that is one of the things we'll we'll never know so if we just focus up see what we've
51:22got here
51:23using a scanning electron microscope mike can find clues about the pigmentation of these ancient
51:29fossil feathers and if we just have a look at this we're at quite high magnification that's 9 000 times
51:37all these sausage shapes then are melanosomes and in a living feather they would be full of the chemical
51:44melanin which which in fact gives the color and these sausage shaped ones are a sure indicator of a
51:50particular kind of melanin which is the one that gives a black or dark brown color so in some cases
51:57like this the the field of view is completely packed with the sausage shaped ones so we know this must
52:03have
52:03been uh intensely black if there were more loosely space we would know it was a paler color maybe dark
52:10brown or even gray right so is it just really the presence or absence of uh of the black pigments
52:16that
52:16you're able to ascertain well the wonderful thing is that there's another form of melanin that gives
52:21a ginger color and so and it is packaged in a different shape of melanosome not this kind of
52:26cigar shaped or sausage shaped one but a spherical one little ball close it up get the vacuum going
52:33a sample taken from a different fossil shows what the structures that carry this ginger pigment look like
52:40well that's entirely different this surface looks like they've taken a melon border and scooped out
52:46lots of little spherical hollows so what color would these melanosomes have made this is definitely ginger
52:55and if you look at a piece of ginger hair from a mammal or a human being that's what you
52:59see also
53:00so is it relatively easy to compare your dinosaur feathers with what's already known about the feathers of
53:07living birds to get that comparison to know what colors you were looking at here we can put the
53:12specimens in one after the other there's the modern one there's the fossil spot the difference no
53:18difference at all and who on earth would have thought a dinosaur is a little close to a bird but
53:23there we are you know it's kind of proved in the skeletons and now if you like proved in the
53:28anatomy of
53:29the feathers for those few dinosaurs from whom fossilized feathers have been found largely in china
53:35we can now put the finishing touches to a reconstruction so has this changed the way
53:41that artists are painting their reconstructions and i mean you've obviously got some dinosaurs
53:45where you've got a very good idea exactly what they look like yes it is changing the way people view
53:50them if we have a look at these paintings of cynosauropteryx which is one of the lovely little
53:56dinosaurs this was probably done five or six years ago it looks a bit odd i mean they've got the
54:01texture
54:01of the feathers and and that's more or less what we would believe from the fossil but they made it
54:06a strange sea green kind of color a few years later the the the same artists are able to produce
54:11a
54:12picture like this which um shows the same dinosaur but with a very definite uh ginger white ginger white
54:19sort of barber's pole stripe on the tail so this is based on your analysis of of color of this
54:25particular dinosaur of this particular dinosaur we we took samples from the dark stripes and we can
54:31say these dark stripes were not red or or black or whatever they were ginger nice that's just amazing
54:38so this is more than just being able to put a bit of color on your illustrations it's actually telling
54:43you something quite important about dinosaurs yes it may say something about behavior which we wouldn't
54:50have thought we could ever get to if they are colored and if they are striped and patterned
54:55there must be some visual purpose yeah signaling of some kind camouflage or sexual display
55:03or a warning thing you know i've got a flash of color don't mess with me you know so there's
55:07all
55:08sorts of reasons they may have had those colors these new discoveries really do bring dinosaurs right out of
55:16the realm of the mythical and the fantastical they're not imagined creatures at all they are real and with
55:24some of them when we have all this information we can look at a reconstruction and know that that is
55:30a
55:30lifelike representation of that animal from the size and shape of its body to the way it holds itself
55:37the way it moves down to its color all of that is rooted in science
55:56back in los angeles last minute preparations are underway to get the dinosaurs ready for the public
56:06it's only now that you get a sense of just how many people have been involved in creating this
56:11exhibition from the artists to the designers to the teams that made the interactive media and the mounts
56:18for the dinosaurs all of it bringing to life the decades of research that our current scientific
56:24understanding relies on the exhibition consists of over 300 specimens it's taken more than six years to
56:40complete and cost tens of millions of dollars
56:54we've created an exhibit that this part of the world has never seen and it's very rewarding for me to
57:03think about the millions of kids and the millions of people that during the next 20 years will visit this
57:11exhibit
57:12and will remember this exhibit for the rest of their lives
57:17these animals look like something out of a comic book or a hollywood studio but they were real
57:24from a pile of dusty bones millions of years old we can put a skeleton back together flesh it out
57:31tell what color these creatures were and even say something about how they grew up
57:37i think this is a unique time to be a dinosaur paleontologist we're finding so much discovering
57:47new dinosaurs and learning new things about them
57:56there are certainly still gaps in our knowledge but i find it amazing just how much we do know
58:00about these extinct animals that no one has ever actually seen alive and that lived so many millions
58:07of years ago the creatures themselves are utterly awe-inspiring but i think so is the incredible amount of work
58:16and the vast numbers of people involved in reconstructing them so that we can come face to face with a
58:23dinosaur
58:33coming up next this evening here on bbc4 what if the dinosaurs had never died out
58:38just one of the questions horizon tackles in a guide to dinosaurs in just a few moments stay with us
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