it was the biggest reptile to walk the earth since Tyrannosaurus Rex a quarter of a ton of cold-blooded killing power meg Alania was one of the greatest predators of all time for more than a million years this giant ruled a continent in a world of hot blooded mammals a monstrous reptile owned the land there would have been nothing alive at that point in time they could have taken it out and there are rumors it still crawls the earth today imagine something as big and powerful as a Nile crocodile but walking around on the land the terror of the outback meg Alania the giant lizard resurrected [Music] Australia isolated by oceans on all sides this island continent has provided a unique environment for evolutionary experiments for millions of years for most of us the image we have of the Australian outback is that of a desolate place populated by small and cute pouched mammals such as kangaroos and koalas the biggest land predator the dingo is no larger than the average dog but Pleistocene Australia one and a half billion years ago was a very different place the continent teamed with enormous marsupials known as megafauna which were anything but cute imagine a monster kangaroo that towered over 2 metres in height and weight more than 225 kilograms the biggest kangaroo that ever lived meat throat copter dog imagine a two and a half metre long wombat that weighed more than 2,700 kilograms meat Diprotodon and feasting on these huge creatures a gigantic meat-eating lizard II wouldn't want to meet Meg Alania meg Alania was one of the greatest predators of all time it ranks with Tyrannosaurus Rex and the great white shark this extinct monster would have dwarfed its modern relatives the monitor lizards such as the Komodo dragon the largest lizard alive today [Music] meg Alania was a huge huge blizzard and when we think of lizards with think of things the size of a little iguana but Meg Alania was a lizard that was bigger than the modern-day Komodo dragon it was one of the largest terrestrial predators of its time this is an animal that was muscle and bone this is a very strong animal and if you look at the construction of its jaws they had jaws they could walk around pretty much any one of his prey item so if it got ahold of something it wasn't gonna let go I would have been more scared of Meg Alania than I probably would have been of an African lion monitor lizards are absolute machines they've got these incredibly tough scales on they're covering their body where the scales actually have chunks of bone inside of them and this is particularly the case for Komodo dragon and lace monitor and therefore meg Alania would have been the same scientists estimate that meg Alania grew over 6 meters in length and weighed more than two-thirds of a ton it's clear that this giant lizard was indeed a mega monster and Meg Alania has earned Australia an unusual distinction Australia is neat that after the age of the dinosaurs it was the only continent that remained dominated by reptiles most of the other continents were dominated by mammals this could be in part by the fact that not only is Australia very isolated but it's also very very hot why did reptiles prevail in this one area when mammals ruled everywhere else the rise of mammals was the result of a global catastrophe sixty-five million years ago a huge asteroid slammed into Earth killing off the giant reptiles we know as dinosaurs with Dinosaurs out of the way mammals evolved into the dominant species ultimately they would rule the planet with one notable exception Australia here evolution took a different route Australia has often been referred to as a natural laboratory because although it's a big place it's also isolated like a big island so if something has a chance of experimenting there it's often gonna take place there dr. Scott Hucknall is the world's leading Meg Alania researcher he spent years piecing together hundreds of fossil bits to reconstruct this monster skeleton 150 years ago meg Alania was only known from a single bone COMPETES of the backbone vertebra over that 150 years museums across Australia have found more and more pieces of that skeleton except for one the skull skull pieces have come into museums over the last 20 years and so what I've done in this study is bring together all those pieces of the skull and reconstruct the head of meg Alania for the first time when you take all the small pieces of the skull and you put them together you realize one really fundamental thing about it it was solid a solid block full of teeth sort of like a crocodile so you can imagine an animal that was really really strong with a very very robust head and use that to kill its prime what was it about Meg Alania that made it such a deadly predator and how did this giant lizard earn the nickname giant Ripper the solid skull of Meg Alania is perfectly adapted for an animal that attacks groups tears huge chunks of flesh out of his brain leaving them to bleed to death the teeth of any predator are the key to understanding how it kills some like those of saber-tooth cats were designed to pierce and slice T Rex's teeth were designed to crush Armour and bone make a lanius teeth both gripped and ripped this is a fossilized jar of Meg Alania and as you can see it has these amazing pointed teeth conical at the base so they're very firm in the jaw it would use these teeth to puncture its prey and rich massive chunks out of it each of mega lanius teeth were armed with a fine series of serrations just like a steak knife what's important about these teeth is that their serrations are on the back which allows the tooth to slice through the flesh when Meg Alania is pulling back on its prey you can imagine what a huge hole that would leave in the side of its prey as blood starts gushing out of the animal with such a huge open way and Meg Alania had a special adaptation that made its bite even deadlier than its modern-day relatives this is a skull from a modern-day monitor lizzard you'll notice that it has a straight tooth line going all the way around to the front this is common amongst all modern-day monitors so that makes meg Elena you unique because if you have a look at its jaw its tooth line is upturned right up to the front of the snout this allows Meg Alania to bite down on this prey and clamp it and what this means is that it can puncture its prey and slice huge chunks of flesh bigger than any monitor living today a huge bite force a huge bite diameter massive blood loss individually each of these adaptations was a lethal weapon all put into one beast they made Meg Alania a killing machine but the competition was also deadly what gave Meg Alania the edge did it have a secret weapon to answer these questions we have to analyze its deadly weapons and investigates how a cold-blooded killer lizard was able to dominate more intelligent warm-blooded mammals [Music] [Music] [Music] we're lucky giant six meter carnivorous lizards don't lurk in the meat section fortunately for us this mega beast became extinct thousands of years ago during the Pleistocene however meg Alania was the apex predator of Australia hunting and killing animals much larger and faster than itself we know about its weapons but how did this hyper carnivore use them and what was its hunting strategy [Music] the few fossils of meg Alania that have been found don't give scientists a lot of clues so we must look to its modern relatives though there are no monitor lizards as big as meg Alania today they probably share a lot of traits with their giant ancestor Brian Frye is a world authority on venomous snakes and lizards and has worked close up and personal with different species of monitor lizards one two lizards are one the ultimate predators they have incredible senses that good sense of hearing but they also have excellent sense of smell they can smell rotting carrion from over a kilometer away and they have great visual acuity as well in this hot environment fry is dressed for the chase despite its size this lace monitor is mega lanius closest living relative very dangerous and an excellent hunter but mega lanius bulk made it easy to spot from a distance and the animals it preyed upon were always listening for danger if you are a prey animal your best defense is to be alert and the best way to be alert is with a hearing so that's why a lot of mammals have very good hearing that they can change the direction of the sensing and they can detect a predator and then they bolt the opposite direction they're more likely to survive so obviously the slow and stupid are the first ones that get eaten if hearing is the key to survival for prey animals how could a giant like Meg Alania get close enough to surprise its prey to help us imagine how much noise meg Alania would have made we asked dr. fry to conduct an unusual experiment well you'll hear some guadalest and so let me put it up near the throat yeah that'll work fry and a member of our film crew temporarily attached a microphone to the lace monitor using removable tape okay he's done he's all ready to go okay good cuz I'm bleeding then we let the lizard loose it's obvious that this is no quiet hunter when you hear that lizard walking through the bush it makes a lot of racket mega Lanie would have made ten times that noise back Alania simply wasn't built for stalking prey quietly it had to find another way but how could a six meter long lizard even locate its prey without revealing itself once again studying its modern relatives may give us a clue most lizards have excellent eyesight but the sense they rely on most to find prey is smell and monitor lizards in particular have a remarkable adaptation to enhance that specific faculty [Applause] they have a very long snake-like tongue which shows their close ancestry to snakes and they use that to smell the air just like a snake would and it's an extraordinarily sensitive detection device for them the scent of a prey animal consists of tiny particles that lift off the creature and float through the air some of the blonde on the lizard's tongue when the lizard retracts its tongue it actually analyzes where the particles came from because the tongue is forked one side is slightly closer to the prey animal more scent particles land on that side and that helps the lizard homed in on its target when they put their tongue out they actually get it out in stereo sling detect left this is right by the tips of it and then help them orient on both directionality and distance but locating a prey animal is just the start how could the giant lizard get close enough to kill the answer ambush it is the most efficient way to hunt much less demanding than running down your food all predatory animals make a trade-off calories in or calories out it all depends on how much energy you use versus how much food you get back in return but Meg Alania would have to stay out of sight hiding behind bushes or in tall grass it typically couldn't see its prey so how would it know when to pounce the mega monster had its own organic radar system meg Alania had an extraordinary super century mechanism that allowed it to visualize its world without actually seeing it it's the same kind of system that crocodiles have which enables them to sense the movements of fish in very murky waters like the crocodile Meg Elena's jaws had a built-in motion detection system sits there with his head on the ground and it uses these sensory pits along the upper and lower jaw to actually sense the vibration from the prey coming along each one of these pits is a nerve ending and it can tell almost 50 feet away whether the prey is big enough for it to bother to even attack meg Alania would hide near water holes and feeding areas where prey animals were likely to pass then it would simply wait for the tell-tale vibrations but even with all these sensory advantages for a cold-blooded reptile to capture hot blooded mammals was still a challenge and this lizard needed a lot of food [Music] for example the Komodo dragon heats up to 80 percent of its body weight in a single meal at twice the size meg Alania would probably have needed to consume twice as much food but what could provide a full course meal for a quarter-ton super lizard how about a two metre tall a two hundred and twenty five kilogram kangaroo and when these two creatures get into a fight anything can happen [Music] scientists believe that Meg Alania became extinct thousands of years ago but persistent rumors claim that a few of these giant carnivorous lizard still lurk in remote stretches of the Australian outback [Music] [Music] of course there is no evidence that a 6-meter lizard is still out there today fortunately for us if mega Lanie were still around today there would be a lot of dead people out there livestock would be in peril the largest living maranatha lizard today Komodo dragons eat goats those are small compared to Michael a Nia and so I would imagine something as big as meg Alania would be taken down cattle during the Ice Age this reptile was the apex predator in a land of giant mammals so what was on the menu on this isolated continent marsupials have become the dominant mammals and many of them were super-sized much larger than the pouched animals we know today the biggest of the lot was Diprotodon this 2700 kilogram herbivore was like a monster wombat the size of a rhino and its size was its best defense and just like today Australia was teeming with kangaroos the only difference is the giant short-faced kangaroos weighed 225 kilograms and stood over 2 metres tall they were able to grab foliage three meters off the ground beyond the reach of other animals this king-size Skippy was a prime prey object but it wasn't an easy target join kangaroo isn't just mate on four legs would have been a formidable foe for any predator to attack these giant kangaroos were the mixed martial arts fighters of the outback like their modern counterparts these extinct Giants defended themselves by kicking with their powerful hind legs they could disembowel an attacker using the claws on their feet this is the thigh bone of the modern grass eating kangaroo it's an animal that might have weight in the order of 100 to 120 pounds we can see when we compare that with the thigh bone of the giant kangaroo just what a marked difference there is to bring down one of these giant critters meg Alania would have to lie in wait until it got close enough to ambush it then the huge lizard would rush forward but the attack would bring it into range of the Kangaroos powerful back legs these are giant kangaroos they're not just going to shrink away a lie down and die they're gonna try and defend themselves kangaroos the animal probably popped back on his tail lashed out those hind legs meg Alenia is far too sturdy to be killed by a kick the Vijayan kangaroo only needs to stun the lizards to give itself time to escape however the monster Roo is slow to accelerate making it extremely vulnerable until it gets up to speed well my money would get mine beyond Meg Alania and although Meg Alania was big and bulky it may not have been as slow as it looked modern monitor lizards are specially adapted as chased predators they have a special technique that enables them to pump more air into their bodies while running they expand their throats to draw in air then contract it to force the air into their lungs this natural supercharger pumps more oxygen into the monitor lizzard system allowing it to sustain high speeds over long distances and what that means is that if they can see a prey item they can run it down Meg Alania may well have shared this ability to accelerate quickly and keep going all it needed was to get close enough to grab the tail of its prey this tile is the integral to a kangaroo's movements and if that were bitten by meg Alania it'll be in a lot of trouble it would try and hop away bleed to death Magdalena would still have it's me even with all its strengths the giant kangaroo is no match for Meg Alania but Meg Alania didn't have this bouncy all to itself there were other predators on the continent most deadly was a bizarre creature called phyla Kaleo carnufex a marsupial lion despite its name it was not a lion or even part of the cat family this beast was actually a distant cousin to wombats and koalas but definitely not huge and cuddly imagine an animal half the size of a tiger with the aggressive personality of a cornered possum the marsupial lion was Australia's largest mammalian predator with flashing claws and grasping hands and blade-like teeth fossil remains of the marsupial lion and its prey have been found all over the continent but one place in southern Australia has become the el dorado of Pleistocene epoch bones over the course of half a million years thousands of animals fell into a labyrinth of underground caverns through sinkholes a few of them ever got out known today as the Naracoorte caves this network of chambers is home to some of the richest fossil deposits on earth including the remains of several marsupial lions paleontologists such as dr. Liz Reed have made some surprising discoveries about the special adaptations that made this unique animal such a deadly predator this is a two hundred thousand year old fossil of the marsupial line's hand and has special features that allow it to be a very effective predator large claws that it can use a slash and pierce prey and an opposable thumb which allowed it to grasp and hold on with those massive claws the marsupial lion had unusually flexible four limbs compared to other predators the bones of the forelimb of the marsupial line reflected strength and flexibility if we look at the elbow you can see a large range of movement in the joint big wide joint wide bones lots of power and unlike a lot of other animals including predators that are restricted to this kind of movement the mass of your lion could reach in and grab prey and hold it to its body allowing the mouth to then deliver the killing blow half a million years after they were made the marsupial Lions tooth marks can be seen on the fossilized skeleton of one of its victims on this bone you can actually see the slice marks produced by this big blade tooth of the muscle your lion so as it's devouring its prey it works at where the muscle attaches to the bone and slices it off so it can eat the flesh the marsupial lion was not all that big about one and a half meters long and less than a hundred and sixty kilograms but it was an agile and crafty animal the tactical killer of its time its sharp claws made it an excellent tree climber it made up for its lack of size by launching attacks from the air taking its prey by surprise a tactic which is given it the nickname drop cat the marsupial lion was absolutely built to get in and close up and personal with big dangerous animals and fight those animals and wrestle those eggs to the ground and the beasts had a phenomenally strong bite pound preparing it had the most powerful bite force of any animal that's ever lived this is a skull of the marsupial lion and basically it's got the most unusual teeth of any mammalian carnival and they would have worked in unison to clamp around the windpipe of its prey something like this these front incisor teeth use for holding or potentially suffocating the prey and then these large blade like premolar teeth we use to slice off pieces of flesh all of these tools combined to make the marsupial lion a lethal opponent the only creature able to challenge Meg Alania these predators would have generally avoided each other but they hunted the same prey and their world was changing the place thus in itself was a tough time it was a time that was dominated by what we call glacial and interglacial cycles culminating in the last equation so for the last ice age that was drier and we had more super droughts than any other time previously as Australia became more arid and food more scarce it's possible that the monster mammal and giant reptile would find themselves competing for prey so we can imagine a scenario where the egg Alania has come into the last of your lives territory it's looking down it sees the giant lizard and perceives it as a threat and then attacks by leaping down onto the lizards once a my soup your line was down on top of the lizard I'd probably go for the neck would not want to take your eyes off the head of Meg Alania it would be a mental battle between two gladiators even Meg Alania would be vulnerable to the Lions death grip on its throat but it had other ways to defend itself the mega lay Nia had another weapon it had a flicking tail so the marsupial whines would have to watch out because of flick from that tail could cause a serious injury if I was a betting person I'd probably put my money on Meg Alania Oh Meg Elena do is get a bite in and the muscle lions a serious trouble the marsupial lion as powerful it was those infected predators that was was really outclassed by the size and never ability of mega lanius megha lanius sheer size would ultimately win the day but in Ice Age Australia even the prey animals such as the mighty Diprotodon were dangerous how could a lizard even a giant lizard tackle a beamer like this some scientists believe that the giant Ripper had a secret weapon Australia today is renowned for its cute quirky and mostly small creatures but less than 70,000 years ago it was a land of monsters the top predator was the giant lizard called meg Alania a 6 meter long mega monster known as the giant Ripper but the biggest beast in the bush was Diprotodon a plant-eating mammal the size of a rhinoceros we're looking at the world's largest marsupial ever an absolute monster now an animal like that has no natural predators no proton probably wasn't very nice it was me and it was large and it would be something that all animals I think would would avoid at two thousand seven hundred kilograms Diprotodon outweighed mega Lanie at ten to one could the killer lizard have brought down this walking mountain of meat meg Alania would have found adult dog protons inherently difficult to tackle the sheer size of Diprotodon in and of itself would have been a very effective defense against predators including Meg Alania but evidence is growing that Meg Alania had a secret weapon that would have allowed it to tackle literally anything including these giant marsupials once again the living monitor lizard offers clues to the past the Komodo dragon regularly hunts animals far larger than itself it has been known to kill water buffalo ten times its own weight it's long been thought that the Komodo dragon has a sort of deadly drool full of infectious bacteria that lives on rotting meat in its gums but bryan fry believes it is a myth the problem with the toxic bacteria theory was that it's based entirely on an absence of evidence there's no evidence for this the one study that looked at the bacteria found pretty much the same bog-standard bacteria you'd find in the mouth of a kindergartener a lion or in the intestinal tract of one of their prey items there's nothing unique in there there's no super toxic bacteria Brian Frye thought there might be another explanation for the Komodos deadly bite the first thing we noticed when we start working with these animals is a huge bulge running a length of the lower jaw on either side but if you go into the reptile Anatomy books it's not in there there's nothing in the anatomy books talking about that even though this is a massive bulge this is not a trivial structure and that got me thinking immediately because this is the exact same location where you find the venom gland of the American Gila monster or the Mexican beaded lizard thought to be the only venomous lizards in the world but they're also very close relatives of the monitor lizards so it was not inconceivable that this bulge was the same gland as the Gila monster and therefore they may be producing the same venom eventually Frey found a way to prove his theory using the preserved head of a very rare Komodo dragon what I have here is a real Komodo dragon head this is a zoo animal that was captive bred that died that we were then allowed the opportunity to use for our research Frei and his team scan the head using MRI technology with the magnetic resonance imaging technology were able to go from the preserved head like this into computer data where we now have everything rendered in three dimensions and what that means is that we can examine what's happening on the inside so here we have the two eyes the gray is the tongue they're the long tongue that you see coming out and then we have showing here two sets of glands on either side the lower set of glands on each side produces venom Frye has discovered that the Komodo dragon isn't the only monitor lizard with this type of venom gland we've looked at monitor lizards now from everywhere where they occur Africa Asia and Australia we've also looked at all different kinds of species whether it be the ones live in the trees the ones on the ground and even the aquatic ones they all have the same generalized gland and they all have very similar venom snakes have powerful muscles specifically for injecting their venom through hypodermic like fans monitor lizards however don't have the ability to inject their poison instead they rely on a different method when the komodo bites its prey the pressure forces venom from the glands into its mouth where it mixes with saliva the toxic brew and oozes into the wound if modern monitor lizards have venom glands is it likely that meg Alania also would have the ability to produce toxins meg Alania was basically just a supercharged place monitor I'd be the closest relative of it now the closest relative of lace one of her is the Komodo dragon we've studied the venom in both a lace monitor and the Komodo dragon so if you have an animal with very similar anatomical features it should logically possess the same venom glands all of this strongly suggests that meg Alania was the largest venomous animal to have ever lived it fries correct this venom gland might have been the secret weapon that gave meg Alania the power to bring down huge prey animals and even compete with other predators no matter how it killed for hundreds of thousands of years meg Alania was the undisputed mega monster of its world but around 50,000 years ago a new predator arrived on the scene the first humans to arrive on the continent found that Australia was a hunter's jackpot the land that Aziz called the lucky country teamed with an endless bounty of edible beasts but those early Australians may not have been the only predators after the abundant prey meg Alania the giant ripper had dominated the land the those early human beings ever cross paths with this monster lizard most scientists believe humans migrated to Australia from Asia or Africa around 50,000 years ago is it likely that meg Alania was still alive at this time to answer this question we must determine the age of the youngest Meg Alania fossils until now there was no way to do this with any degree of certainty the well-known carbon-14 dating method can only be used on fossils up to 40,000 years old much later than the arrival of the first humans but this machine allows us to extend our ability to date fossils much further into the past it's called the Tim's the thermal ionization mass spectrometer now that allows us to push the daily limit back to somewhere between 500 to 600 thousand years so you know a long long wait wait wait outside of that radiocarbon dating barrier dr. price ran 10 samples taken from Meg Alania teeth through the Tim's price is still reviewing his findings but the preliminary results indicate that meg Alania may well have been alive 50000 years ago around the time humans arrived on the continent we've got some exciting new data that's starting to come out based not only on direct fossil evidence but also on the dating as well and it's starting just that we do have a time overlap between the last of the megafauna specifically animals like meg Alania and some of the first human colonizers that entered Australian if this is true dr. Price's research could rewrite the history of prehistoric Australia if humans and Meg Alania did live in Australia at the same time they could have encountered each other what then [Music] how effective would the primitive weapons of the first Aspray Lian's have been against a venomous giant lizard six metres long this is a fire hardened tip on the end of a spear this is the sort of spear that people would have used in the Pleistocene this in fact is made out of Mulder it's heavy it's very strong would be very difficult to break and it's the sort of spear that's needed for thrusting and you know people either side jabbing the similar weapons to distract it but even with all this happening this is not really a weapon that would really help you again smegal a Nia running from megalo Nia wasn't an option either like all monitor lizards this creature was remarkably fast the speed with which komodo dragons can run for example they can run up a hill faster than I can run down it a hundred pound human being would not have stood a chance against a 20 foot long mag Alania or even a 12 foot long mag Alania it would have been launched meg Alania was Australia's alpha predator for at least half a million years a big mega ley Nia would have no natural predators there would have been nothing alive at that point in time they could have taken it out yet this giant lizard which had ruled the continent eventually died out it disappeared leaving only a few fossilized bones to mark its legacy how could such a mega beast vanish without a trace many people think that extinction is an instant process something that occurs over night but extinction is a very complicated process and it usually happens over thousands and thousands of years we don't know why Meg Alania became extinct it could have been because of climate change or it could be because of human hunting on perhaps a combination of both the fact is all the megafauna in Australia became extinct Meghalaya amongst them despite the occasional rumors that meg Alania is still lurking in the Australian outback paleontologists have no doubt that the giant lizard is long gone it would seem that the age-old rivalry between reptiles and mammals has been settled [Applause] but there are still plenty of mega lanius relatives alive today the monstrous Komodo dragon can reach a length of three meters and has been known to kill people humans have been around for about 200,000 years but monitor lizards have survived for 60 million years there's no question that these cold-blooded killers are quite capable of making a comeback if humans were to go extinct it's pretty easy to imagine that a giant monitor lizard would again evolve from in the Australian environment all over need is for the top predator the humans to go away and they'd be back as dominant predators same sauce mega line it may be figure