72 Dangerous Animals: Prehistory | S2 E6 | Zephyr Nature

Dinosaurs ruled the earth for over 165 million years. There were many theropods throughout the Mesozoic era that were extremely formidable. We've picked 72 that dominate the others. In this show, we will talk about these dangerous animals, including when they lived, what they ate, their weaponry, and how humans would fare if these creatures were still alive. From the tyrant lizard king, to the lord of the lizard eaters, to the meat eating bull, this is 72 Dangerous Animals: Prehistory! Yutyrannu

s grew up to 30 feet long and weighed up to 3,100 pounds. It lived 125 million years ago in China. Yutyrannus, the beautifully feathered tyrant, is the largest carnivorous theropod confirmed to have feathers through direct fossil evidence. It was a tyrannosaur from the Early Cretaceous period, and had three fingers, rather than two, and long arms. This is due to it being an earlier form on the family tree than other known tyrannosaurs. It had massive claws on each finger that would have been dan

gerous weapons. Yutyrannus had crests along both sides of its snout. Its feathers were 6-8 inches long and covered its entire body. The feathers were likely used for thermoregulation, considering the area it lived in had an average yearly temperature of 50 degrees fahrenheit. The fact that basal tyrannosaurs, such as Yutyrannus, had feathers, means that later and more advanced tyrannosaurs may have also had feathers covering their bodies. Yutyrannus’ feet weren't specialized for running, however

it could still reach speeds of 25 miles per hour. Yutyrannus was likely a pack hunter, and may have hunted sauropods as its prey. It had a bite force of over 11,500 Newtons. This large tyrannosaur could easily finish off an unlucky human. Yutyrannus takes first for now. Can it be overtaken by Marsh’s lizard? Marshosaurus grew up to 20 feet long and weighed up to 550 pounds. It lived 155 to 152 million years ago in North America. Marshosaurus was a medium sized megalosauroid from the late Jurass

ic period. It lived in an area with distinct wet and dry seasons. It fed on small and medium sized dinosaurs, such as Stegosaurus. It was in turn eaten by Saurophaganax, Torvosaurus, and the apex predator in the area - the 40 foot long super Allosaurus. We have very little skeletal material of Marshosaurus. This means either it was a rare dinosaur, or it mostly lived away from the areas that other dinosaurs were preserved in. Marshosaurus was built for strength. Its strong arm bones suggest that

Marshosaurus was adapted for holding onto prey and subduing it. Marshosaurus had great eyesight. It attacked prey in either an ambush or by running it down. It had serrated teeth, useful for ripping prey apart. Marshosaurus was very speedy and agile, and could easily catch and kill you. Marshosaurus wasn't as dangerous as Yutyrannus. It takes second place. Up next, an outlier that might not even be a theropod. Herrerasaurus grew up to 20 feet long and weighed up to 770 pounds. It lived 231.4 to

228.9 million years ago in South America. Herrerasaurus was one of the earliest dinosaurs to appear in the fossil record. It was a saurischian from the late Triassic period. Herrerasaurus’ taxonomic status has been heavily debated. It possibly wasn't a theropod and may not have even been a dinosaur, despite its heavy resemblance. Herrerasaurus was lightly built and had a relatively small head. It had five toes on each foot and five fingers on each hand, however, only three digits were functiona

l on each limb. It had long arms with huge hands. It could use its hands to grasp prey. Herrerasaurus lacked almost all specializations found in later dinosaurs. It hunted small to medium sized plant eaters. Puncture marks on a Herrerasaurus skull reveal that it was preyed on by Saurosuchus, which was featured in our first season of 72. A different Herrerasaurus skull has bite marks from another Herrerasaurus obtained in a fight. Herrerasaurus coprolites were found with small fragments of bone i

n them, meaning this predator was capable of digesting bone. This beast could use its sharp teeth to end you quickly. Herrerasaurus falls into last place. Yutyrannus holds onto first. Next up, a massive oviraptorosaur. Gigantoraptor grew over 26 feet long and weighed up to 6,000 pounds. It lived 96 million years ago in Mongolia and North America. Gigantoraptor, the giant thief, was a massive oviraptorosaur from the late Cretaceous period. At up to 20 feet tall, Gigantoraptor was the largest ovir

aptorosaur of all time. The only known skeleton was a young adult individual, meaning it was not quite yet fully grown. This individual was 11 years old at the time of its death. It had an insanely fast growth rate that was much speedier than other non-avian theropods. Even though Gigantoraptor was absolutely gigantic, it was more bird-like than its smaller relatives, as seen in its skeletal morphology. While smaller oviraptorosaurs were fully feathered, Gigantoraptor was likely partially naked.

This is because it relied on body mass to regulate its temperature, whereas the smaller oviraptorosaurs relied on feathers for insulation. Even though its body was likely without feathers, Gigantoraptor still probably had arm and tail feathers that would have been used to help guard its nest from predators, as well as for display purposes. Gigantoraptor's legs were abnormal compared to other large theropods. The larger a theropod is, the shorter and stockier the legs are in order to combat a la

rger mass. Gigantoraptor, however, had an extremely long femur and tibia, both of which were 3.6 feet long. This means that Gigantoraptor was adapted for running and maintaining high speeds for extended periods of time. Gigantoraptor had a large horny beak that it used to feed on plants, as well as meat. Just like the modern tuatara, Gigantoraptor could slide its jaws forward and backward to slice up veggies and meat. It had a shearing bite that could cut up plant material as well as meat, unlik

e smaller oviraptorosaurs, which used their jaws to crush food. Gigantoraptor was a generalist feeder, meaning it wasn't picky about what it ate. Gigantoraptor created nests to lay their eggs in. They laid 26 massive eggs that were two feet long in a round nest with a diameter of 10 feet. Gigantoraptor had extremely powerful hind limbs, and could run at speeds of up to 42 miles per hour long-distance. Gigantoraptor’s kick would have been extremely lethal to humans. It's essentially Superman kick

ing Steppenwolf in the Snyder Cut. All of your bones would shatter, and you would go flying through the air for several dozen feet. While Gigantoraptor would not have been interested in hunting humans, if you approached its nest or got on its bad side, it would be game over for you. It could trample you, kick you, or stomp you to death. Gigantoraptor was very dangerous, but wouldn't have actively hunted you. It wasn't a predator, which results in it taking second. Marshosaurus moves to third, an

d Herrerasaurus to fourth. Incoming, a quilled carcharodontosaur. Concavenator grew up to 20 feet long and weighed up to 880 pounds. It lived 130 to 125 million years ago in Spain. Concavenator was a small carcharodontosaur from the early Cretaceous period. It was actually the smallest member of the carcharodontosaur family. Other carcharodontosaurs, such as Carcharodontosaurus, grew up to 41 feet long. Concavenator had a hump on its back formed by tall vertebrae in front of the hips. It is thou

ght that the hump was a visual display to attract mates. Concavenator had thin quill-like structures on its arms. The quills could have been full-on feathers too. Concavenator is thought to have been a social animal that would have used its quills and hump to communicate with other members of its species. It may have been a pack hunter. Because of its small size, Concavenator may have banded together to take down larger prey. It is likely that Concavenator cared for its young. Concavenator preye

d on small and medium sized dinosaurs. It lived in areas with lakes, wetlands, and swamps. It had long teeth that it could have used to rip you apart. Concavenator wasn't as dangerous as Yutyrannus or Gigantoraptor. It takes third, pushing Marshosaurus to fourth and Herrerasaurus to fifth. Up next, our episode’s highlight and the stereotypical dinosaur fan’s favorite dinosaur. Tyrannosaurus grew up to 43 feet or larger and weighed up to 20,000 pounds. It lived 72.6 to 65 million years ago in Nor

th America. Undoubtedly, the most famous dinosaur of all time was Tyrannosaurus rex. It is known by nearly everyone on the planet, is featured in hundreds of documentaries, shows, and movies, and has more merchandise than any other prehistoric creature. What you may not know however, is that the tyrant lizard king originally had a different and much more boring name, leading to outrage in the scientific community and general public. Here's the complete history of Tyrannosaurus rex. It all starte

d in 1892, when two vertebrae were named Manospondylus gigas by Edtard Stinker Cope. The name Manospondylus gigas means “giant porous vertebrae”. The vertebrae were named towards the end of the infamous “Bone Wars”, meaning that along with a large chunk of other fossils, they were named with little research or care. The Bone Wars was simply a competition to name as many species as possible. Many of the species named should be combined in the same genus, and even multiple genera should be combine

d due to a lack of major differences. Keep in mind that even in humans there is a whole lot of skeletal variation. Some humans are 7 feet tall, others only 3 when fully grown, some have 10 fingers, others have 8 or 12, there are differences between skulls and dentition as well, etc. Dinosaurs with the slightest differences are classified as different genera. For instance, if we found a Tyrannosaurus with 3 fingers on each hand, rather than two, even if it was otherwise identical skeletal wise, p

aleontologists would be like “new genus,” rather than considering that it may have had a mutation and been a rare specimen. The paleontologists might even say that this rewrites the entire family tree of the Tyrannosaurs, when in reality it's no different than a human with an extra pinky on each hand. It would still be a Tyrannosaurus in reality, but not in the eyes of the paleontologists. Nowadays, it can take a long time to get a new species or genus named. This allows for as much accuracy as

possible, and careful consideration of the placement of the taxa. Back to Tyrannosaurus’ history, a Kansas man named Barnum Brown discovered the remains of a Tyrannosaurus rex in Montana in 1902. Later, in 1905, the skeleton was given the official name “Tyrannosaurus rex” by Henry Fairfield Osborn. In a paper by Osborn in 1917, he pointed out that the Manospondylus and Tyrannosaurus vertebrae strongly resembled each other. However, nobody batted an eye. At least, not at the time. The Black Hills

Institute of Geological Research rediscovered the original fossil site for Manospondylus gigas in the year 2000. Remains of Tyrannosaurus were uncovered at the site, confirming that Tyrannosaurus and Manospondylus were the same species. Now, according to the ICZN rules, the first name given to a genus has priority over any names given later. This meant that from then on, all references and mentions of Tyrannosaurus must be called Manospondylus instead. This resulted in public outrage, because w

ho in their right mind would prefer to call the Tyrant Lizard King “giant porous vertebrae” instead? Luckily, however, a revision done to the ICZN rules meant that any junior synonym that was widely used for a creature that was given before 1899 could be used as the accepted name, rather than the senior name. Pretty much the only mentions of the name Manospondylus were references to the similarity between it and Tyrannosaurus. Meanwhile, Tyrannosaurus was the most popular dinosaur on the planet.

And, just like that, Tyrannosaurus got to keep its name, much to the relief of the scientific community and general public. Now that we've talked about how Tyrannosaurus came to be known, we can dive into its fascinating habits and biology. While Tyrannosaurus wasn't the largest carnivorous dinosaur, as that title was taken by Spinosaurus, it was still the largest carnivorous animal to ever set foot in North America at 43 feet long and 20,000 pounds in weight. Tyrannosaurus Sue, the most comple

te individual and most famous Non-binary, measured 40 feet long and was 28 years old at the time of their death. However, other individuals are known to have been larger. The maximum age for a Tyrannosaurus has been calculated at 30 years. Since we have discovered so many different Tyrannosaurus skeletons of different ages, it was possible to put together a growth curve for the species. This revealed an S shaped curve, showing that for the first 10 years of their lives, Tyrannosaurus grew slowly

. During the next 10 years, Tyrannosaurus had a period of rapid growth, increasing in size from one tenth of their size to nearly their maximum size. The last 10 years of Tyrannosaurus’ life had slowed growth, once more. While Tyrannosaurus had around the same length lifespan as other tyrannosaurs, it grew much longer and heavier in the same span of time. It has been heavily debated whether Tyrannosaurus was a predator or a scavenger. Some arguments for this include its speed. Tyrannosaurus was

nowhere near as fast as depicted in Jurassic Park or other movies. It definitely could not keep up with a speeding Jeep. In order to run 25 plus miles per hour, Tyrannosaurus would need 80% of its muscle mass in its legs, which is completely unheard of. It is estimated that Tyrannosaurus would have had a running speed of 11 miles per hour - much slower than other theropods. It also couldn’t maintain this speed for long. Its preferred walking speed was only 3 miles per hour. This does not mean Ty

rannosaurus was a scavenger. As seen with other animals, such as Dunkleosteus, the predator only needs to be fast enough to catch its prey. Tyrannosaurus preyed on large herbivorous dinosaurs, including Triceratops, Ankylosaurus, and Edmontosaurus. These dinosaurs weren't meant for speed. Tyrannosaurus’ stride was larger than its prey’s, meaning it didn't require as much energy to walk and could outlast its target long-distance. Another argument for Tyrannosaurus being a scavenger is that its ar

ms were too tiny to be useful. This is an extremely invalid argument, however. Tyrannosaurus had a much larger head proportionately than dinosaurs with longer arms, such as dromaeosaurs. Dromaeosaurs used their front and back limbs to attack prey, since they had a much smaller head proportionate to body size. Tyrannosaurus, on the other hand, used its head and extremely powerful bite force to take out its prey. Additionally, its arms weren't useless. Abelisaurs had such useless arms that they co

uldn't even bend their wrist or elbow, and most of their fingers didn't even have claws. Their arms were so small that they might not have even been visible on the outside of their body, with the skin and muscles covering them up. Tyrannosaurus on the other hand, had fully mobile joints and could lift 440 pounds with its arms. Another thing to consider is that if an animal no longer needs a certain feature, over time it evolves to not have that feature anymore. Tyrannosaurus didn't need its arms

for killing prey, therefore it wasn't necessary to have larger arms. Instead, it used its head, which was held at the perfect height to bite the necks and backs of its prey. A single bite from Tyrannosaurus in the right spot would cripple or kill its prey instantly. There is an Edmontosaurus skeleton with bite marks on its vertebrae from a Tyrannosaurus. The bones had healed, meaning that the Edmontosaurus was alive when the Tyrannosaurus bit it, and it survived the encounter. However, if Tyran

nosaurus’ bite was an inch deeper, the Edmontosaurus would have been killed in the attack. Tyrannosaurus had a bone crushing bite, which was necessary for chomping through Ankylosaurus armor and Triceratops horns. Tyrannosaurus had an amazing sense of smell that it would have used to detect prey or carrion. Almost all predators also scavenge when presented the opportunity. This is because the carcass is a free meal that Tyrannosaurus wouldn't have to waste energy attacking, or risk injury from t

he prey fighting back. Tyrannosaurus had a great sense of sight, as well as smell. The back of Tyrannosaurus' head was much wider than the front, resulting in binocular vision and great depth perception. This allowed it to know when it was close enough to strike at prey. Tyrannosaurus could tell the distance between it and its prey, if its prey was moving, and how fast its prey was traveling. Eagles can see 3.6 times better than humans, but Tyrannosaurus could see 13 times better than humans. Ty

rannosaurus would have been capable of seeing an object 3.7 miles away. Tyrannosaurus had a bite force of 35,000-57,000 Newtons. Its mouth was U shaped, rather than V shaped. The U shape gave Tyrannosaurus a bigger bite than other theropods, such as Allosaurus, and allowed it to rip off more meat at a time. The teeth on the side of Tyrannosaurus' mouth could bite through bone, and were up to a foot long, including the root. Tyrannosaurus had lips to cover its teeth. Tyrannosaurus was once consid

ered to be sluggish and cold-blooded, as were other dinosaurs. Tyrannosaurus' rapid growth curve provides evidence for warm-bloodedness. Cold-blooded animals have a constant growth rate, growing at the same pace throughout their entire lives, while Tyrannosaurus and other dinosaurs had periods of rapid growth throughout their teenage years. It is possible that very young Tyrannosaurus had down feathers covering its body as insulation. However, we know for a fact that adult Tyrannosaurus' were co

mpletely featherless. While Yutyrannus fossils have been found with feather imprints, Tyrannosaurus fossils have been found with pebble-like scaly skin. The Tyrannosaurus skin found shows that in areas where Yutyrannus had feathers, Tyrannosaurus was bald. Prehistoric Planet lied to you. There are two different size classes of Tyrannosaurus skeletons. There is a larger and heavier form and a smaller and lighter form. It was once thought that the larger ones were females and the smaller ones were

males. Additionally, it was believed that the females had a shorter chevron on the first tail vertebrae, that way eggs could pass through. However, some of the skeletons thought to be females had a full length chevron, disproving that theory. While it is impossible to tell the difference between male and female for most Tyrannosaurus skeletons, one skeleton is confirmed to be female, due to the presence of medullary tissue in her remains. Medullary tissue stores calcium that is used to produce

eggshells. This tissue is only present in females, meaning that the Tyrannosaurus skeleton must be female. Medullary tissue has also been found in several other dinosaurs. In 2005, paleontologists broke a Tyrannosaurus femur apart to transport it. On the inside, was fibrous bone matrix tissue and blood vessels. It used to be thought that soft tissue was incapable of being fossilized, but this proved otherwise. While there is evidence for pack hunting in some tyrannosaurs, such as Yutyrannus and

Albertosaurus, there is none for Tyrannosaurus. Several Tyrannosaurus skulls have what appear to be bite marks from other Tyrannosaurus. It was once thought that these Tyrannosaurus were fighting for dominance. However, now it is thought that the marks were caused by a parasite that infected the Tyrannosaurus when they drank from water where the parasite was found. Modern birds are affected by a parasite called Trichomonas, which causes growths on the soft tissue of the birds and scarring on the

bone. It is thought something similar happened to these Tyrannosaurus. In 2010, it was suggested that Tyrannosaurus may have been cannibalistic. Strong tooth marks were found on the legs and feet of a Tyrannosaurus skeleton. The Tyrannosaurus was already dead when eaten, however, since the legs of a living Tyrannosaurus would have been the farthest point away from the mouth of the other Tyrannosaurus. If a Tyrannosaurus were to attack another living Tyrannosaurus, it would go for the head or ne

ck. The legs have some of the smallest amounts of muscle mass, meaning that the victim was a long-dead carcass that was picked clean by the time the other Tyrannosaurus got to it. In 1955, a new tyrannosaur skeleton was discovered in Mongolia. It was named as a new species of Tyrannosaurus, Tyrannosaurus bataar. The skeletons of Tyrannosaurus rex and Tyrannosaurus bataar were so similar from side view that with a quick glance they could not be easily distinguished. However, in 1965, Tyrannosauru

s bataar was renamed Tarbosaurus bataar, as it was evident that it was a separate genus. There were a few differences between the skeletons, as well as them being from different continents. However, in all reality, while Tyrannosaurus and Tarbosaurus may be different species, they are likely in the same genus. Just because they were found on totally different continents, doesn't mean anything. Look at Jaguars and Lions. South America and Africa. They are the same genus. They have differences in

their skeletons too. So, why is it necessary to classify Tarbosaurus separately from Tyrannosaurus? Because paleontologists are underpaid and therefore don't have the time to look into things like this, even though it's common sense. A difference between Tyrannosaurus and Tarbosaurus is that Tyrannosaurus has a much wider skull. Another tyrannosaur named Zhuchengtyrannus is more closely related to Tarbosaurus than Tarbosaurus is to Tyrannosaurus, meaning that Tyrannosaurus and Tarbosaurus were n

ot that closely related. However, once again, this is comparing morphology, rather than genetics, meaning this method of linking creatures taxonomically is not, nor ever will be 100% accurate. And, considering The Bone Wars naming spree, not even close to 100%. For example, Hyenas and dogs look similar. Most people even assume they are related. However, Hyenas are practically cats through DNA analysis and are much more closely related to cats than to dogs. Another example is within vultures. New

World and Old World vultures may look similar, but Old World vultures are birds of prey, and New World vultures are not, and are much more closely related to storks. They evolved similarities through convergent evolution. Yet another example is the Emerald Tree Boa and Green Tree Python. Pythons and Boas are not actually as closely related as you think, even though these two species look almost identical. In 2022, Tyrannosaurus rex was split into three species. The two additional species were n

amed Tyrannosaurus imperator and Tyrannosaurus regina. Tyrannosaurus Sue became the holotype for Tyrannosaurus imperator and Wankel Rex became the holotype for Tyrannosaurus regina. The species were split apart based on the robustness of skeletal elements, mentioned earlier, including the femur, maxilla, dentary, humerus, ilium and metatarsals. Tyrannosaurus imperator is thought to be the ancestor to T. rex and T. regina since all of its specimens date to an earlier period stratigraphically. In

2024, a tyrannosaur skeleton discovered in 1983 was described and named Tyrannosaurus mcraeensis. It existed at a period in time before Tyrannosaurus rex - around 5-7 million years earlier, to be exact. T. mcraeensis was estimated to be 40 feet long. It had a proportionately longer bottom jaw with a less prominent chin than T. rex, as well as blunter teeth and a weaker bite. It is thought that Tyrannosaurus may have cared for and fed its offspring. In a 2021 paper, it was estimated that there we

re anywhere from 165 million to 41 billion Tyrannosaurus alive throughout their existence. The average estimate for the number living at one time resulted in an estimate of 2.5 billion Tyrannosaurus alive throughout their existence. It is thought that only one in 80 million Tyrannosaurus would become fossilized. To summarize, Tyrannosaurus is estimated to have grown up to or over 43 feet long and weigh up to 20,000 pounds. It could run 11 miles per hour for short distances, or walk 3 miles per h

our, more comfortably. It could see an object up to 3.7 miles away. It had a bite force of up to 57,000 Newtons. It could kill pretty much any other carnivorous dinosaur. This massive meat-eating monster could easily kill a human, at least, if it could catch you, that is. While it may have been slow, it could still quickly make sharp turns while running, and pivot on a single foot. Juvenile Tyrannosaurus, however, could run up to 38 miles per hour. To be honest, Tyrannosaurus should take second,

but that would piss off the entire dinosaur fan base, so, by default, it takes first and wins the episode. Yutyrannus finishes in second, Gigantoraptor in third, Concavenator in fourth, Marshosaurus in fifth, and Herrerasaurus in sixth. Tyrannosaurus moves onto our finalists. While this time Tyrannosaurus gets accommodations, for the finale, it will not. Prepare for disappointment. Next episode on 72 Dangerous Animals: Prehistory, the king of gore, the reversed vertebrae, and the southern thief

. Non-avian dinosaurs were around for longer than they've been extinct. This means that there were dinosaur fossils in existence while dinosaurs were still alive. In each episode we will rank the creatures from 1-6 on a scale of how potentially dangerous these creatures would be to humans, and the winner of each episode will showdown with the other 11 finalists in the season finale to decide on which prehistoric creature was the ultimate human killing machine!