Tag Archives: t-rex

Research suggests T. rex had a cooling system in its head

The Tyrannosaurus rex, the most feared and iconic of all the dinosaurs, had a cooling system in its skull that allowed him to deal with prehistoric heat and humidity. The new study from scientists in Missouri, Ohio, and Florida, challenges previous beliefs about this cranial structure.

Credit: Wikipedia Commons

T. rex, known as one of the largest meat-eating dinosaurs on the planet, has two large holes in its skull, called the dorso-temporal fenestra — basically two “windows” in the back of its head. Scientists used to believe that they were filled with muscles that helped with jaw movements but now this was challenged by a new study.

Similar holes can be found in the skulls of a class of animals known as diapsids, an extremely diverse set of animals grouped together because of this particular feature (this class includes not only crocodilians, but also birds, lizards, and tuatara). The holes are thought to have evolved about 300 million years ago.

“It’s really weird for a muscle to come up from the jaw, make a 90-degree turn, and go along the roof of the skull,” Holliday said. “Yet, we now have a lot of compelling evidence for blood vessels in this area, based on our work with alligators and other reptiles.”

Researchers looked at alligators at the St. Augustine Alligator Farm Zoological Park in Florida, using thermal imagining to translate heat into visible light. The new evidence obtained offers a new theory and insight into the anatomy of a T. rex’s had, they argued.

Because alligators are cold-blooded (or ectothermic) their body temperature is dependent on the temperature of their environment. This means that their thermoregulation processes are very different from warm-blooded, or endothermic, organisms.

“We noticed when it was cooler and the alligators are trying to warm up, our thermal imaging showed big hot spots in these holes in the roof of their skull, indicating a rise in temperature. Yet, later in the day when it’s warmer, the holes appear dark, like they were turned off to keep cool,” said Kent Vliet, coordinator of laboratories at the University of Florida’s Department of Biology.

The researching team worked with the thermal imaging data to examine fossilized remains of dinosaurs and crocodiles, trying to understand how this hole in the skull changed over time.

“We know that, similarly to the T. rex, alligators have holes on the roof of their skulls, and they are filled with blood vessels,” said Larry Witmer, professor of anatomy at Ohio University’s Heritage College of Osteopathic Medicine. “Yet, for over 100 years we’ve been putting muscles into a similar space with dinosaurs. By using some anatomy and physiology of current animals, we can show that we can overturn those early hypotheses about the anatomy of this part of the T. rex’s skull.”

It’s not yet known whether dinosaurs in general and T. rex in particular, were ectothermic or endothermic. The topic is actually under debate, with some scientists thinking the former, some the latter, and some believing dinosaurs fell somewhere between the two – a feature called mesothermy.

Nevertheless, what the new research published in the journal The Anatomical Record, suggests is that T. rex and other dinosaurs used some of the thermoregulation tactics of ectotherms. The actual meaning of this within the broader context of their metabolisms is yet to be explored.

Thai T. rexes.

Two new dinosaurs found in Thailand are smaller, cuter, but still deadly cousins of the T. Rex

Researchers from the University of Bonn and the Sirindhorn Museum in Thailand have identified two new cousins of T. rex.

Thai T. rexes.

Image credits Adun Samathi / University of Bonn.

The fossils of these two species were discovered in Thailand some 30 years ago, but hadn’t been studied until now. Both dinosaurs are relatively distant cousins of T. rex, the team reports, with a somewhat more primitive body structure. However, they were both effective predators.

The fossils were first unearthed three decades ago in Thailand and were subsequently passed over to the Sirindhorn Museum, where they were never examined in detail. Adun Samathi, a paleontologist currently doing his doctorate at the Steinmann Institute of Geology, Mineralogy, and Paleontology at the University of Bonn, re-discovered them in the museum’s archives around five years ago as part of his thesis efforts. He brought some casts of the fossils to the University of Bonn to analyze them together with his doctoral supervisor, Prof. Dr. Martin Sander, using state-of-the-art methods.

The results offer us fresh insight into the history of megaraptors. Tyrannosaurus rex is part of this lineage of carnivorous dinosaurs, whose name means “giant thieves”. There is some resemblance between the two new species and the iconic predator — they all, for example, ran on their hind legs and had a similar body structure. Unlike T. rex, however, the two new species had strong arms that ended in long, vicious-looking claws. Their heads were also more delicate and had long snouts.

“We were able to assign the bones to a novel megaraptor, which we baptized Phuwiangvenator yaemniyomi,” explains Samathi.

The Cthulu-like name was chosen in honor of where the fossils were discovered — the Phuwiang district, Thailand — and the discoverer of the first Thai dinosaur fossil, Sudham Yaemniyom.

Phuwiangvenator was likely a very adept runner, judging by its anatomy. But it was much smaller than T. rex, only growing about six meters in length (so about half the size). The discovery is pretty exciting if you’re into dinosaurs (and who isn’t?) because megaraptors, so far, had predominantly been discovered in South America and Australia. Phuwiangvenator’s body structure seems to indicate that the lineage actually originated in this area, from which it eventually spread far and wide.

“We have compared the Thai fossils with the finds there,” says Samathi. “Various characteristics of Phuwiangvenator indicate that it is an early representative of this group.”

“We take this as an indication that the megaraptors originated in Southeast Asia and then spread to other regions.”

The other set of fossils that Samathi uncovered during this doctoral research seem to belong to another as of yet unidentified species. Sadly, there wasn’t enough material to clearly determine its ancestry; however, the team believes it was also a predator related to Phuwiangvenator and T. rex. Christened Vayuraptor nongbualamphuenisis, this dinosaur seems to have been the runt of the litter — it measures around 4.5 meters in length. It’s not much information to work from, but the size alone is useful as it paints a richer tapestry of the ancient ecosystem that these dinos lived in and the roles they undertook.

“Perhaps the situation can be compared with that of African big cats,” explains Samathi. “If Phuwiangvenator were a lion, Vayuraptor would be a cheetah.”

The two new predatory dinosaurs will be presented to the public today to mark the tenth anniversary of the Sirindhorn Museum. The event will be opened by the Thai Princess Maha Chakri Sirindhorn.

The paper “Two new basal coelurosaurian theropod dinosaurs from the Early Cretaceous Sao Khua Formation of Thailand” has been published in the journal Acta Palaeontologica Polonica.

Illustration of T. Rex hatchling. Credit: AMNH.

This is what T. rex probably looked like as a baby

Illustration of T. Rex hatchling. Credit: AMNH.

Illustration of T. Rex hatchling. Credit: AMNH.

Tyrannosaurus Rex was the most well-equipped, specialized, and fearsome predator of its day. With its huge, menacing jaw and puny arms, T. rex is also one of the most recognizable dinosaurs in the world — but that doesn’t mean we know exactly what it looked or behaved like. Based on the latest fossil discoveries and research, paleontologists at NYC’s American Museum of Natural History (AMNH) have opened a new exhibit that showcases T. rex as you’ve never seen it before, in various life stages — including an adorable fully feathered baby model. Seriously, this is cute aggression material.

Computer animation of T. rex hatchling. Credit: ANMH.

Computer animation of T. rex hatchling. Credit: ANMH.

The exhibit, called “T. rex: The Ultimate Predator”, features reconstructed models of the apex predator as a hatchling, as a four-year-old, and as an adult. The most surprising exhibit is the hatchling model, which is fully adorned with feathers, looking cute as a button. The turkey-sized hatchling would have grown very fast, about 65 kg (140 pounds) per month, until it reached up to 6,800 kg (15,000 pounds) as a fully adult behemoth about 20 years later. The young predator likely snacked on insects and small vertebrates before it matured.

Speaking of which, the adult life stage is also equipped with a lot more feathers than previous interpretations. Tufts of feathers adorn the T. rex’s head and run down its spine, giving it more bird-like features. It’s skin is also more leathery, akin to that of the foot of a chicken or the leg of a turtle.

Four-year-old T. rex model on display at the “T. rex: The Ultimate Predator” exhibit at the ANMH. Credit; ANMH.

Four-year-old T. rex model on display at the “T. rex: The Ultimate Predator” exhibit at the ANMH. Credit; ANMH.

Although no one has ever found fossilized feathers in a T. rex skeleton, researchers have discovered many tyrannosaur relatives that fit this description, such as the famous Dilong paradoxus first unearthed in China in 2004. But, at the same time, this also means that the AMNH interpretation is speculative — at most, it’s an inferential leap. The dinosaur’s color is also debatable, although insights from new research are very exciting. By dissolving small pieces of T. rex bones, researchers have been able to isolate some soft tissue cells such as melanin and keratin. Keratin — the protein that skin, hair, and nails are made of — ranges in color from purple to orange to red. T. rex‘s scale-like skin could have been orange or brown, but we can’t tell for sure until researchers can find more evidence.

Judging from the predator’s cranial structure, we now know that T. rex didn’t really sound like a lion’s roar. Far from the Jurassic Park interpretation, researchers say that T. rex likely sounded like a crocodile’s bellow.

Adult T. Rex on display at AMNH. Credit: AMNH.

Adult T. Rex on display at AMNH. Credit: AMNH.

What is less open to interpretation is T. rex‘s strength and diet. Recent x-ray fluorescence and microscope analysis of coprolites (fossilized feces) show that they were made by up to 50% bone. This suggests that T. rex‘s mighty jaws, which could bite with 7,800 pounds of force, easily crushed the bones of its prey. As for the dinosaurs’ laughably disproportionate forearms, experts believe that T. rex didn’t use them much.

T. rex might also have been smarter than the average tyrannosaur, having a larger brain and more pronounced olfactory bulb that allowed it to smell and hear prey from a long distance. Brain casing analysis also shows that its eyes faced forward like a hawk, offering the dinosaur a great depth of vision.

The new exhibit opened Monday, March 11, 2019, and will run until August 9, 2020.

Moros intrepidus. Credit: Jorge Gonzalez.

New species of small tyrannosaur ancestor sheds light on T. Rex’s path to becoming ‘King of the Dinosaurs’

Moros intrepidus. Credit: Jorge Gonzalez.

Moros intrepidus. Credit: Jorge Gonzalez.

Tyrannosaurus rex is in the public’s mind the ultimate apex predator during the age of the dinosaurs. It is true that few other dinosaurs were as fierce and well equipped to take down even some of the toughest game in prehistoric times as T. rex was. However, T. Rex was not born a king — the dinosaur had to climb up the evolutionary ladder and, just like everybody else, it started out from humble beginnings. The path T. rex took in order to become “the king of the dinosaurs” is still mysterious but thanks to the discovery of a 96-million-year-old ancestor, paleontologists are now filling the blanks.

“With a lethal combination of bone-crunching bite forces, stereoscopic vision, rapid growth rates, and colossal size, tyrant dinosaurs reigned uncontested for 15 million years leading up to the end-Cretaceous extinction – but it wasn’t always that way,” says Lindsay Zanno, paleontologist at North Carolina State University, head of paleontology at the North Carolina Museum of Sciences and lead author of the new study. “Early in their evolution, tyrannosaurs hunted in the shadows of archaic lineages such as allosaurs that were already established at the top of the food chain.”

The newly discovered tyrannosaur species, named Moros intrepidus, was found in Utah by a team of paleontologists at the North Carolina Museum of Natural Sciences and North Carolina State University. It stood just 3 feet to 4 feet tall and weighed about 170 pounds — about the size of T. Rex’s skull, which appeared about 15 million years later, during the Cretaceous.

That’s not to say that Moros intrepidus, which means “harbinger of doom,” was harmless. The fossils suggest that it was an extremely agile predator, easily capable of running down prey while avoiding confrontation with the top predators of day, such as allosaurs. Zanno estimates that their Moros was more than seven years old when it died, nearly fully grown.

“Although the earliest Cretaceous tyrannosaurs were small, their predatory specializations meant that they were primed to take advantage of new opportunities when warming temperatures, rising sea-level, and shrinking ranges restructured ecosystems at the beginning of the Late Cretaceous,” Zanno explained. “We now know it took them less than 15 million years to rise to power.”

The new study published in the journal Communications Biology documents a blank slate in the fossil record between the period when allosaurs dominated the planet’s surface and the time when T. rex made its appearance.

“When and how quickly tyrannosaurs went from wallflower to prom king has been vexing paleontologists for a long time,” Zanno said. “The only way to attack this problem was to get out there and find more data on these rare animals.”

 

Moros also revealed the origin of T. rex’s lineage on the North American continent. Interestingly, when researchers placed Moros on the family tree of tyrannosaurs, its closest relatives were found in Asia.
T. rex and its famous contemporaries such as Triceratops may be among our most beloved cultural icons, but we owe their existence to their intrepid ancestors who migrated here from Asia at least 30 million years prior,” Zanno says. “Moros signals the establishment of the iconic Late Cretaceous ecosystems of North America.”

 

Nanotyrannus and the Skeptical Criteria for Species

The classification of varying species, even the very term species itself, has long been a puzzling element of taxonomic categorization. Pulled from the Latin phrase species (meaning “appearance”), the term, in regards to its scientific use, has more than two dozen different definitions.

Based on this information alone, we can see how precisely pinpointing what declares a specimen a specific species is not quite clear. It is, perhaps, unique to each individual case. Numerous factors need to be taken into account. When biologists examine an organism to see if it is identical to or distinct from another species, they analyze its attributes. In comparing it to other organisms, they look for common characteristics or reproduction compatibility, or the lack of either.

However, when studying the remains of organisms of eons past, definitively declaring a species can be more difficult. Take a look at the drawn-out Jane and Nanotyrranus dilemma, for example. More than 15 years ago now, a dinosaur skeleton was unearthed in Montana by a team from the Burpee Museum of Natural History from Rockford, Illinois. The remains were rather well-preserved. They belonged to a ferocious carnivore of the Cretaceous Period. But what kind of carnivore?

Skeleton of a T. Rex. Source: Wikipedia.

It was a tyrannosaurid. Well, that narrows it down a bit, kind of like narrowing one’s selection from mammals down to bears. We have eliminated countless possibilities, yet there are quite a few bear species to go through. Similarly, there is a variety of species of tyrannosaurids to compare the remains of one to.

It was 20 feet in length, 7 feet in height, and its gender was undetermined. Regardless of that trifling mystery, the tyrannosaurid was dubbed Jane. Paleontologists made their observations. But not all agreed on what the appropriate classification of this specimen should be. Some suggested it could be a Nanotyrannus, a species of dwarf tyrannosaurid, whereas others believed it to simply be a juvenile specimen of Tyrannosaurus rex.

Jane on Display at Burpee Museum. Credit: Wikimedia Commons.

The debate was on. Upon further research, the existence of Nanotyrannus has been a sketchy one, as far as some scientists are concerned. As Dougal Dixon puts it in his extensive World Encyclopedia of Dinosaurs and Prehistoric Creatures, “Some paleontologists regard Nanotyrannus as a juvenile specimen of something better known, or even a dwarf species of Albertosaurus or Gorgosaurus” (324)”, which are other tyrannosaurids.

Jane’s remains were not the first to be suggested to be those of Nanotyrannus. In 1942, David Dunkle found the skull of a carnivorous dinosaur which resembled that of Jane. Dunkle’s discovery was tagged “CMNH 7541.” After this, other paleontologists examined the fossil on numerous occasions. Each suggested it was a certain species of previously known tyrannosaurid, such as Albertosaurus. It would not be until the late 1980’s that the skull would be suggested to be something more.

Robert Bakker. Credit: Wikimedia Commons.

Robert Bakker. Credit: Wikimedia Commons.

Renowned modern paleontologist Robert T. Bakker and his associates took another look at CMNH 7541. This time though, the scientists were able to use a variety of advanced practices in their combing of the skull. One of these was the use of CAT scans. Bakker’s team ultimately determined it to be an utterly new species, calling it Nanotyrannus.

However, this skull, like the remains of Jane, has more recently fallen under scrutiny again. Some experts, such as Thomas Carr, have pointed to the presence of the factor of mere growth to explain the differences between “Nanotyrannus” and other tyrannosaurids. Carr and others have stated that the features of this supposed new species are different from those of its relatives only because the specimens of “Nanotyrannus” were juvenile examples of another species.

Once again, technology managed to come to the rescue. Fossilized bones carry LAG’s, lines of arrested growth. Like tree rings, these natural markings can allow us to better distinguish the age of a prehistoric creature. In order to detect the LAG’s, a tiny bit of practically weightless bone must be cut off. This is what was done with a segment of bone from Jane. (This could not be done with CMNH 7541 since a weightless fragment of bone cannot be extracted from the fossilized skull.)

Jane remains on display at the Burpee Museum. You can see the dinosaur in her museum habitat in this video I was able to shoot of Jane. It features some of the other skeletons on display at the Burpee Museum as well.

From the fragment taken from Jane, scientists concluded that Jane was merely a teenager, around 12 years old. With tyrannosaurs typically reaching adulthood around 20, Jane’s LAG’s showed the dinosaur was, in fact, a juvenile. Most now consider Jane simply a very well-preserved specimen of juvenile T. rex.

Despite the whole controversy over Jane’s identity, the existence of Nanotyrannus has not altogether been ruled out. This is just one example of the confusing, perpetually ongoing discussions regarding what classifies an organism under a certain species.

Researchers investigate intriguing ‘baby’ tyrannosaur fossil

The “fabulous” fossil probably belongs to a young Tyrannosaurus rex that lived 66.5 million years ago — but it also could also be a mature specimen of a smaller carnivorous dinosaur.

Back at the lab, the researchers found the fossil glowed under a black light. Credit: University of Kansas.

Tyrannosaur fossils are always a treat, but finding one as well-preserved as this one is a special treat. The fossil features a complete section of the upper jaw with all of its teeth intact, along with bits of the specimen’s skull, foot, hips and even backbone. Judging by the preliminary analysis, the fossil seems to belong to a juvenile, which means it could offer new perspectives on how tyrannosaurs evolved and developed — but it also means more questions.

Whenever you’re working with fossils that are tens of millions of years old, you’re bound to deal with some uncertainties. The Nanotyrannus (as the specimen has been named) is hard to attribute to one species or another because not many juvenile fossils have been found.

“The teeth suggest it’s a Tyrannosaurus rex; however, there is still more work to be done,” said David Burnham, preparator of vertebrate paleontology at the KU Biodiversity Institute. “Because a young T. rex is so rare, there are only a few that have been found over the years, so it’s difficult to discern what are changes due to growth or if the differences in the bones reflect different species. Fortunately, KU has an older T. rex to compare with and another young T. rex on loan to help decipher this problem.”

Many animals show growth lines in their bones as they are developing — kind of like tree rings. However, as the bone ages and is potentially damaged, regular repair procedures are carried out to renew bone, and these procedures can mask each other, hiding the real age of the bone.

In this case, researchers are planning a microscopic analysis of the fossil bones that were brought into the lab, and they’re also preparing for a new trip to the original fossil site to see if they can find more of it.

“Confusing the issue here is age,” Burnham said. “Ontogeny, that’s the process of growth—and during that process we change. Adult dinosaur bones, especially in the skull, don’t look the same as their younger selves. So, if someone finds a baby or juvenile fossil they may think it’s a new species, but we have to be careful since it may represent a younger growth stage of an existing species. It’s reasonable to assume Nanotyrannus could be valid—but we must show it’s not just a stage in the life history of T. rex.”

After the analysis concludes, we can expect a paper addressing the position of this fossil on the family tree of theropod dinosaurs and answering the most pressing of questions: was it a T-Rex, or not.

Credit: Ideatrash.

T. Rex’s tiny arms weren’t meek after all — new research says they were meant for ‘vicious slashing’

Meeting the giant carnivorous dinosaur eye to eye must have been a gruesome sight during the Cretacious. Shifting the gaze a bit south from T. Rex’s menacing jaw, however, would have shown a pair of puny arms. This contradictory appearance has made the dinosaur a laughing stock, one big fossilized joke and a favorite running gag among nerds everywhere in the world.

Well, the joke’s on you, bud. Steven Stanley, a paleontologist at the University of Hawaii at Manoa, says T-Rex’s short forelimbs could have actually been an asset during close encounters with prey, allowing the dinosaurs to viciously slash anything in front of it.

Credit: Ideatrash.

Credit: Ideatrash.

For decades, paleontologists and biologists have debated how T. Rex used its arms. One leading hypothesis is that the dinosaur’s forelimbs were vestigial — a structure that served a purpose at some point far back in an animal’s family tree, but was gradually reduced in size and functionality as an adaptive response to millions of years of evolutionary pressure. Others have suggested that T. Rex used its arms to grab onto females when mating; lever itself off the ground if it happened to get knocked down by an opponent; or as a clutch to closely hold onto prey long enough for the dinosaur’s killer jaws to make the final blow.

Less ‘clumsy’, more ‘ferocious’

It’s important to note that while T. Rex’s forelimbs were indeed small in relation to the dinosaur’s huge body and jaws, they were still one meter (three feet) in length and may have been capable of bench-pressing over 180 kg (400 pounds) each. Stanley has identified several clues that suggest T. Rex mini-arms were actually secret weapons capable of inflicting ferocious damage.

For starters, the arms are strong and robust, as indicated by the bones that make up the limbs themselves but also the coracoid, which is the shoulder bone that helps control arm movement. Being so short in relation to the dinosaur’s towering body, the arms would have been perfectly adapted to slashing at close quarters. Another hint is that T. Rex had two claws on each forelimb instead of the typical three most other theropods feature. Having just two claws would have helped T. Rex exert 50 percent more pressure when slashing and clawing. The (8-10 cm long) sickle-shaped claws would have caused deep wounds.

“Its short, strong forelimbs and large claws would have permitted T. rex, whether mounted on a victim’s back or grasping it with its jaws, to inflict four gashes a meter or more long and several centimeters deep within a few seconds — and it could have repeated this multiple times in rapid succession.”

“Infliction of damage by slashing was widespread among other theropod taxa, so in light of its formidable weaponry, why should T. rex not have engaged in this activity?” Stanley wrote about his findings presented at the annual conference of the Geological Society of America. 

T-rex

Credit: Wikimedia Commons.

The fossil record does indeed point to the fact that T. Rex’s arms shrank over time as its jaw became bigger and more powerful. But rather than becoming useless evolutionary remnants, the dinosaur’s forelimbs would have still packed a deadly punch in close-quarters combat.

For now, scientists aren’t entirely sure what the deal with T. Rex’s arms is. More biomechanical studies such as this might help shed light on the issue because the dinosaur’s dynamics aren’t yet fully understood. For instance, Thomas Holtz at the University of Maryland, who wasn’t involved with the research, said T. Rex had “to push its chest up against the side of the victim” in order to deploy its limbs for damage.

In any event, T. Rex’s arms don’t seem that silly anymore, that’s for sure.

Fossil Friday: Sciurumimus albersdoerferi, the single-fossil theropod

S. albersdoerferi fossil found in the Plattenkalk formation in Peinten, Germany.
Image credits to wikimedia user Toter Alter Mann

This fierce little guy is a Sciurumimus albersdoerferi. Well, it’s actually the only S. albersdoerferi we’ve ever found. He belongs to an extinct genus of coelurosaurian theropods that lived some 163 to 145 million years ago, in the Late Jurassic. Theropods were initially carnivorous, however, several groups are known to have evolved into other kinds of diets, from herbivorous to insectivore and omnivore. Based on the shape of his jaw and teeth, S. albersdoerferi was most likely a meat-eater (though we don’t know if he prayed on other dinosaurs, fish, or insects.)

And theropods have passed this wide diet to a very colorful part of life today — they’re the direct ancestors of modern birds. The link was established based on the fact that both theropods and birds have a wishbone and hollow skeletons. Some theropods even had feathers.

Now, this specimen is a fossil of a juvenile S. albersdoerferi so we don’t know what size an adult might grow to. As a group however, theropods tended to grow larger than any of the predators that came before them. To get an idea, think of the reconstructions of T-Rex you saw in Jurassic Park — also a theropod.

Do not want to be that guy.
Image credits wikimedia user Matt Martyniuk

 

 

Artist impression of Timurlengia euotica in its natural environment 90 million years ago. Credit: Todd Marshall

Brain before brawn: T-Rex first evolved a clever brain

T. Rex is one of the most popular dinosaurs, for good reasons too. It was one of the biggest carnivorous dinosaurs to walk the planet, and a fierce looking one to boot. Though its laughable  two-fingered forearms were puny, the rest of its body was built for slashing pray: a huge skull fitted with razor-sharp teeth which lent one of the most powerful bites ever, powerful thighs and tail that allowed the dinosaur to run at up to 25 mph, and a big overall body which rendered it immune to other predators. Essentially, it grew its way to the top of the food chain. To get there though, T-Rex first had to evolve a big brain with keen senses, a new research suggests.

Artist impression of Timurlengia euotica in its natural environment 90 million years ago. Credit: Todd Marshall

Artist impression of Timurlengia euotica in its natural environment 90 million years ago. Credit: Todd Marshall

Tyrannosaurus rex was big, but its predecessors were small. The first tyrannosaurs, which were human- to horse-size, originated about 170 million years ago during the mid-Jurassic. Though lacking in stature, these little tyrannosaurs had advanced brains and advanced sensory perceptions, including hearing that would put any of us to shame, says Dr. Steve Brusatte from the University of Edinburgh’s School of GeoSciences.

Reconstructed skeleton of “Timurlengia euotica” with discovered fossilized bones, highlighted in red. Credit: t Proceedings of the National Academy of Sciences

Reconstructed skeleton of “Timurlengia euotica” with discovered fossilized bones, highlighted in red. Credit: t Proceedings of the National Academy of Sciences.

Brusatte and colleagues identified a new dinosaur species called  Timurlengia euotica, which lived 90 million years ago and was an ancestor to T. rex and other tyrannosaurs. T. euotica, which was unearthed in Uzbekistan, fills a 20 million year gap in the fossil records. The analysis suggests “only after these ancestral tyrannosaurs evolved their clever brains and sharp senses did they grow into the colossal sizes of T. rex,” Brusatte said.

Previously, researchers weren’t sure how T-rex evolved into such cunning, yet massive hunters. Though smaller than those of T-rex, T. euotica’s skull and brain suggest very sharp senses and a powerful brain for its size, CT scans revealed. Since T-rex  predecessors  were already pretty apt cognitively, the logical explanation is the dinosaurs first had big brains, then worked on brawn.

“New discoveries like this show that there is still so much to be discovered about the history of dinosaurs,” says Hans Sues, a scientist at the Smithsonian’s National Museum of Natural History, and one of the authors of the paper. “It’s not every day that you find a new tyrannosaur.”

Findings appeared in PNAS.

tyrannosaur tracks

Paleontologists follow the trail of tyrannosaurs: rare multi-step tracks revealed

When he was only 13 years old, Scott Persons was led to a sandstone slope right next to the Glenrock Paleon Museum, Wyoming. The museum’s curator gently brushed away at an intended spot and soon enough three uncanny dinosaur tracks revealed themselves to Persons, who was dumbstruck at the sight. Many years later, Persons — now a doctoral student in paleontology — returned to the site, studied it extensively along with colleagues and made a scientific report of the three dinosaur tracks carved in the stone by the eons. As it turns out, these findings belong to a tyrannosaur and are absolutely unique.

tyrannosaur tracks

Credit: Scott Persons

Each track shows three big toes each with sharp claw tips. and a small fourth claw at the rear. Based on these markings and their size, the paleontologists concluded that these were definitely made by a carnivorous dinosaur. There were more clues. Made  66 million years ago, or roughly around the time of the major mass extinction that wiped dinosaurs off the planet, the trail was definitely made by a tyrannosaur.

The researchers filtered their list of suspects even further until they finally reach two prime candidates: an adolescent Tyrannosaurus rex or the closely-related smaller tyrannosaur Nanotyrannus lancensis. In any event, the findings bear evidence of the first multi-step tracks of either species known to science, as reported in Cretaceous Research.

“Having a trail of tracks is important,” says Persons. “With it, you can calculate an estimate of how fast the tyrannosaur was walking.”

The tyrannosaurs must have walked at a speed of 4.5 to 8 km/h. This shows that, even when walking, tyrannosaurs moved faster and covered more ground in a single step than the large herbivores, such as the duckbilled dinosaurs, which they coexisted with and presumably hunted. A T-rex could run as fast as 29 km/h. A human would definitely not stand a chance in out-running the king.

If you’re in Wyoming around Glenrock, don’t miss this show!

“The tracks are still in the field,” says Persons. “If you go to Glenrock, today, visit the Plaeon Museum, and are up for a little hike, you can see the prints just like I did.”

tyrannosaurus_1

New evidence that T-Rex was indeed a cannibal

Tyrannosaurus was one of the fiercest land predators ever, despite claims that the dinosaur was mostly a scavenger. While this is true to a degree, T-Rex was most definitely a hunter at heart even though the predator might have munched on a carcass or two from time to time. Apparently, the dinosaur even ate its own kind, a new study suggests.

tyrannosaurus_1

Loma Linda University paleontologist Matthew McLain and colleagues found bone fossils belonging to T-Rex which had clear cut marks on them which could have been made by no else but another T-Rex. These marks show the bone was gnawed, and this is possible only with serrated teeth. Now, most  theropod dinosaurs – a group of biped dinosaurs which includes T-Rex, but also Velociraptor, Spinosaurs and, uhm, birds – have serrated teeth. However, considering the length of the cut marks the suspect list was narrowed down to two dinosaurs: Tyrannosaurus rex and the Nanotyrannus lancensis. These are the only two theropods in the Lance Formation – a division of Late Cretaceous rocks in western US. Upon further investigation, the researchers posited that the cut marks could have only been made by a T-Rex, hence evidence of cannibalism.

“We’re sure it was feeding, these are feeding traces,” McLain said. “The marks were made either near death or after death, because there is no sign of healing on them. If the animal was bitten and survived then the spots would heal.”

In other words, the prey could have either been already dead when the other T-Rex took for free lunch (scavenging tricks again) , or was killed by the other theropod.

 The Tyrannosaur long bone laced with serrated teeth marks. Image: MATTHEW MCLAIN

The Tyrannosaur long bone laced with serrated teeth marks. Image: MATTHEW MCLAIN

This is the third paper that suggests T-Rex sometimes may have engaged in cannibalistic practices. In 2010, paleontologist Nicholas Longrich found three foot bone fossils belong to T-Rex, including two toes, and one arm fossil all retained big tooth marks made by some other T-Rex. The cut marks were made by feeding. Then, earlier this year,  Dr David Hone from Queen Mary, University of London found a T-Rex skull littered with numerous injuries, many of which came from bites.  There is even a circular, tooth-shaped puncture hole in the back of the head from a particularly savage bite. The creature was bitten by other T-rex even after it was killed, as it was decaying.

It seems cannibalism was quite common among Tyrannosauruses, which isn’t necessarily surprising. Male lions will sometimes kill and eat the cubs of their rivals, in order to establish dominance in the pack and ensure the survival of their own bloodline. Even before they’re born, sand tiger sharks will cannibalize each other in the mother’s womb, the biggest baby shark (with the biggest teeth) devouring its unfortunate siblings.

 

A detail of a thin section through the tooth of a large theropod, Gorgosaurus, from Alberta. Credit: Danielle Default

T-rex and other top dinosaur predators had serrated teeth to butcher their prey

A novel analysis reveals T-rex and other theropods – the top land predators that dominated the planet for no less than 165 million years – had teeth of unrivaled complexity. The long and powerful teeth were serrated like steak knives to disembowel prey easily, while on the inside tissue supported the teeth for maximum resistance against the powerful sheering stress which followed each bite.

Gorgosaurus feeding on a young Corythosaurus in Alberta, Canada, 75 million years ago. Image: Danielle Dufault

Gorgosaurus feeding on a young Corythosaurus in Alberta, Canada, 75 million years ago. Image: Danielle Dufault

Over millions of years, theropods developed an unrivaled arsenal. Though not very fast, these huge beasts would overwhelm any prey, no matter how large, which had the misfortune of encountering a theropod. Among the fossil teeth analyzed by University of Toronto Mississauga paleontologist Kirstin Brink and colleagues were those belonging to the smaller Coelophysis and bird-like Troodon, but also large predators Allosaurus, Gorgosaurus, Daspletosaurus, Tyrannosaurus and Carcharodontosaurus, along with those of semi-aquatic Spinosaurus.

“[..] The serrations were most efficient for piercing flesh and gripping it while ripping off a chunk of meat, called the ‘puncture and pull’ feeding style,” Brink said.

A detail of a thin section through the tooth of a large theropod, Gorgosaurus, from Alberta. Credit: Danielle Default

A detail of a thin section through the tooth of a large theropod, Gorgosaurus, from Alberta. Credit: Danielle Dufault

The researchers carefully section fossilized teeth, either alone or confined in the ribs and other bones of prey, then used a scanning electron microscope and a synchrotron. This offered an unprecedented view both of the meat eaters’ tooth structure and chemical composition. Like a very strong saw, the teeth of T-rex and its cousins were disposed in a manner that allowed each teeth to be supported by those surrounding it. When and if a tooth happened to come out, it would be replaced. T-rex, for instance, took two and a half years to grow a new tooth.

“It could take up to two years for a tooth to grow back in the big theropods like T. rex. Therefore, having specially reinforced teeth means less tooth breakage and less gaps in the jaw, leading to more efficient eating,” Brink said.

Today, only one animal with serrated teeth is still alive: the infamous Komodo dragon. The 10 foot long Indonesian lizard has teeth that closely resemble those of ancient theropods. It uses them to chomp  huge prey, life buffalo. Interestingly enough, the Komodo isn’t a descendant of dinosaurs and evolved its serrated dentures independently.

Turkey Sized Vegetarian T-Rex Discovered

A seven year old has discovered the fossil of a turkey-sized dinosaur that roamed South America over 140 million years ago. The tiny dinosaur was related to T-Rex, but had few similarities to it; aside for its size, the dinosaur was a vegetarian, munching on plants instead of terrorizing other creatures.

Chilesaurus diegosuarezi grew up to ten feet long Photo: Reuters

At the end of the Jurassic period, the Earth was very different from what it is today. Average temperatures were a whopping 3 degrees Celsius higher than today, there was virtually no frozen landmass, and of course, dinosaurs ruled the planet. But while most dinosaurs were huge and terrifying Chilesaurus diegosuarezi was nothing of sorts.

It had short arms and hands with two fingers, like T-Rex, but feet that resembled long-necked dinosaurs. It could grow up to ten feet, but the discovered specimen was about as big as a turkey. It was part of the same group as Velociraptor and Tyrannosaurus, from which modern birds evolved, but it’s just strange.

“Chilesaurus is so unexpected, so drastically different than anything else we’ve seen before. It’s an anatomical Frankenstein,” says Lindsay Zanno of the North Carolina Museum of Natural Sciences in Raleigh.

Photo: Reuters

The species really riddled paleontologists, who have rarely seen such a hybrid and enigmatic dinosaur. So strange was the dinosaur that initially, scientists believed they were dealing with several different species.

“It’s like a T. rex that’s been shrunk but not shrunk equally,” says Pete Makovicky, an associate curator and dinosaur specialist at The Field Museum in Chicago, who was not involved in the new find. “This animal would’ve looked more silly than fearful … more similar to an ostrich than to T. rex.”

The fossil was actually discovered 11 years ago, when Diego Suarez was only 7 and he was accompanying his geologist parents on an expedition, and the little boy playing actually discovered the dinosaur, who was named in his honor – a remarkable case of beginner’s luck.

“Out of nowhere, two small things appeared. … They were fossils,” Suarez says by email. He ran to show his mother. His parents, he says, “were amazed. You (can) imagine it was, to them, like wining the lottery.” The family sent the fossils to dinosaur specialists in Argentina.

Diego Suarez has a passion for fossils. (Photo: Manuel Suarez)

In terms of evolutionary significance, Chilesaurus seems to throw a curveball. Its ancestors were meat eaters, its living relatives were meat eaters, but it ate plants. It had vertebrae and front limbs like T-Rex and velociraptor, but its feet, ankle and some of its pelvis looked like they belonged to a completely different branch of plant-eating animals. In a way, it’s like a platypus – a creature that embodies distinctive traits from entirely different species.

Martin Eczurra, a PhD student at Birmingham University said:

“Chilesaurus can be considered a ‘platypus’ dinosaur because different parts of its body resemble those of other dinosaur groups due to mosaic convergent evolution. In this process a region or regions of an organism resemble others of unrelated species because of a similar mode of life and evolutionary pressures.”

It might also provide some insight into evolution itself.

“Chilesaurus provides a good example of how evolution works in deep time and it is one of the most interesting cases of convergent evolution documented in the history of life. It comes as false relationship evidence may arise because of cases of convergent evolution – such as that present in Chilesaurus.”

Journal Reference: Fernando E. Novas et al. An enigmatic plant-eating theropod from the Late Jurassic period of Chile. Naturedoi:10.1038/nature14307

An arrow marks the spot where a dinosaur lost its footing while crossing a slippery mudflat Image: Seth Hammond

Fossilized footprints reveal a clumsy dinosaur

Crossing  the riverbed of Carrizo Creek in Oklahoma, a series of tracks made by a two-legged dinosaur have been preserved in time for 150 million years. The tracks reveal a most clumsy scene, as the dinosaur in question slipped for a second before going back to his beaten path.

An arrow marks the spot where a dinosaur lost its footing while crossing a slippery mudflat Image: Seth Hammond

An arrow marks the spot where a dinosaur lost its footing while crossing a slippery mudflat
Image: Seth Hammond

When first analyzedin the 1980s, paleontologists described some 47 tracks, but due to erosion, only 14 are visible today. Nevertheless, they still capture a most interesting moment as two of the tracks show signs of the dinosaur stumbling.  One has a ridge of mud pushed out and up along its side. The other one is strangely deep — about 0.6 inches (1.6 centimeters) deeper than any of the other tracks.

“What we finally decided is, what must have happened is that the dinosaur slipped as it was walking across this really slippery mudflat, and then that’s where it caught itself,”  said  researcher J. Seth Hammond, a graduate student in geosciences at Fort Hays State University in Hays, Kan. of the second, deep track.

“In a way, what’s interesting is the everyday trivia,” Hammond said. “He’s just walking across a mudflat and slips like anyone else might.”

The species of the dinosaur is unknown, but paleontologists are fairly certain it belonged to a class of dinosaurs called Therapods, which also includes famous two-legged predators like T. rex and Deinonychus.

via Scientific American

It’s settled – Tyrannosaurus Rex hunted for live prey

The king of all predators, the godfather of his time, la creme de la creme – Tyrannosaurus Rex (T. Rex) was the ultimate predator… or was he? When Jurassic Park came out, even though the cinema crowd went wild as T. Rex smashed and ate velociraptors (and the occasional human), at the time, there was no compelling proof that the dinosaur actually hunted – some teams actually claimed that he was a scavenger.

trex

In 2011, a team from the Zoological Society of London reaffirmed T. Rex as the mean green killing machine we all know:

“It is effectively impossible for Tyrannosaurus rex to have fed solely or almost completely on carcasses of dead animals. T. rex lived in an ecosystem with a large number of smaller-bodied carnivorous dinosaur species and it couldn’t have relied on carcasses for its diet,” said Sam Turvey, a co-author of the study published in Proceedings of the Royal Society B.

It seemed obvious that T. Rex was a hunter. But few doubts still remained. Now, another study seems to pin the final nail in the scavenger theory.

The researchers found a T. rex tooth stuck between vertebrae in the tail of a herbivorous duck-billed hadrosaur. The fossils came from a famous area in South Dakota – the Hell Creek Formation.

This CT scan of a duck-billed hadrosaur's vertebra shows an embedded T. rex tooth crown with bone tissue that regrew around it.

This CT scan of a duck-billed hadrosaur’s vertebra shows an embedded T. rex tooth crown with bone tissue that regrew around it.

The finding is very significant because the T. rex tooth is surrounded by bone that clearly grew after the tooth became lodged there. This could only happen if the predator bit the herbivore’s tail, lost its tooth there, as well as the prey.

“It’s a smoking gun. We finally have Tyrannosaurus rex caught in the act,” says Bruce Rothschild, a palaeopathologist at the University of Kansas in Lawrence and a co-author of the paper. “We’ve seen plenty of re-healed bite marks attributed to Tyrannosaurus rex, but it’s hard to confirm identity with those,” says Thomas Holtz, a vertebrate palaeontologist from the University of Maryland in College Park. “Actually having the broken tooth makes it easy to determine who was doing the hunting here,”

But even with this, some are hard to convince.

“I’ve long argued that Tyrannosaurus rex was an opportunist like a hyena, sometimes hunting and sometimes scavenging. This provides no evidence to the contrary,” says Jack Horner, a palaeontologist at the Museum of the Rockies in Bozeman, Montana, who served as scientific adviser on the Jurassic Park films.

But even as a few argue that he wasn’t a pure predator, and more argue that he in fact was, even a larger group is just fed up by this debate.

“Great galloping lizards!” exclaims John Hutchinson, an evolutionary physiologist at the Royal Veterinary College in London. “It is so frustrating to see provocative half-baked ideas about celebrity species like Tyrannosaurus rex drawing the public’s attention when there is so much more interesting palaeontology to be talking about.”

Via Nature

Tyrannosaurus skeleton auctioned, despite controversy and court order

I’ve studied geology for four years – and I still haven’t had the chance to see a T-Rex skeleton; this is just one of the reasons why I believe such valuable fossils belong in museums, where they could serve the higher purpose of education, and not in some personal collection, where they serve only the vanity of the rich – especially when it comes to such a rare specimen.

The rare Tyrannosaurus Bataar, seven metres long (23ft), was bought by an anonymous bidder for more than $1m (£630,000) in New York. The sale went on, despite vehement protests from the Mongolian president, who claims the dinosaur, which was found in Mongolia was exported illegally, and perhaps even more important, despite a court order released by a Texas judge which declared the auction illegal.

Robert Painter, the attorney who obtained the court order, stood up at the beginning of the auction with the Texas judge on his cell phone and noted the restraining order; almost everybody was shocked as, despite this turn of events, the attorney was asked to leave and the sale proceeded.

“I am very surprised that Heritage Auctions, Inc. knowingly defied a valid court order, particularly with the judge on the phone, listening and ready to explain his order,” Painter says, in a statement.

We will keep you posted as events continue to unfold.

Artist impression of a group of Yutyrannus, the largest feathered animal known to man and a close relative to the T. Rex, which lived during the Cretaceous period. On the far left are two Beipiaosaurus depicted, the previously largest feathered animal.

T. Rex relative had an extensive plumage – biggest feathered dinosaur ever found

Artist impression of a group of Yutyrannus, the largest feathered animal known to man and a close relative to the T. Rex, which lived during the Cretaceous period. On the far left are two Beipiaosaurus depicted, the previously largest feathered animal.

Artist impression of a group of Yutyrannus, the largest feathered animal known to man and a close relative to the T. Rex, which lived during the Cretaceous period. On the far left are two Beipiaosaurus depicted, the previously largest feathered animal.

A remarkable paleontological discovery surfaced from China recently, after scientists reported they’ve found fossils belonging to the Yutyrannus huali,a very close relative of the Tyrannosaurs Rex, which prove that its entire enormous bus-sized body was covered in feathers. This officially makes it the biggest animal covered in feathers ever found, and also forces paleontologists to rethink some of the leading feather-related evolutionary theories.

The Yutyrannus h., whose name translates as “beautiful feathered tyrant”, used to live some 125 million years ago in what’s today northeastern China. Judging from the  three specimens of the bipedal tyrannosaur found by paleontologists in the area, it’s believed the dinosaur weighed at least 1,400 kilograms and was covered with a filamentous plumage at least on its neck, pelvis and legs. It’s foot is typical of other early tyrannosaur relatives, however its distinct plumage is what makes this dinosaur so incredibly fascinating, unique to an animal of this size.

Yutyrannus fossil clearly showing plumage evidence - its feathers were as long as a pencil. (c)  Zang Hailong

Yutyrannus fossil clearly showing plumage evidence - its feathers were as long as a pencil. (c) Zang Hailong

Previously, the largest feathered dinosaur ever found was the Beipiaosaurus, which measured just 2 meters in length and could have easily been wrapped around by two human hands. The podium jump has now been marked by a visible discrepancy. Scientists used to thought that as a feathered animal becomes larger, it gradually loses its plumage until it becomes completely gone. The Yutyrannus, however, proves otherwise. Paleontologists believe its plumage had a thermal insulating role at its core, keeping it warm and cool at the same time, according to the ambient temperature. In the area and time the Yutyrannus used to live, the temperature was cooler by eight degrees Celsius than other dinosaur habitats at that time, which serves as a pertinent explanation. Yutyrannus was a fascinating beast, nevertheless, one that is certain to provide some important evolutionary clues in the near future.

Yutyrannus artist impression

Yutyrannus artist impression

The findings were reported in the journal Nature.

[via Scientific American]

T. Rex bite computer analysis

T. Rex’s bite was the strongest ever of any terrestrial being

T. Rex bite computer analysis

Although the T. rex isn’t the largest carnivorous dinosaur to have roamed Earth, a new study which used computer models to reconstruct its skull muscles reveals that his bite was the most powerful one ever of all terrestrial animals, extinct or living.

Biomechanicists at Liverpool University, UK,  used laser scanners to digitize the skulls of a human, alligator, a juvenile and adult T. rex, and Allosaurus. They then made a jaw muscle computer reconstruction and performed a bite analysis. These were scaled up to the T. rex‘s skull, for a relevant comparison.

Previous studies estimated T. rex’s bite had a force of 8000 to 13,400 Newtons, however for many years these figures have been questioned considering the dinosaur weighed around six tones. The new analysis suggests that the T. rex was capable of generating a biting force of 35,000 to 57,000 newtons at its back teeth – four times bigger than past estimates and around ten times more powerful than the bite force of today’s modern alligator.

When studying the T. rex juvenille’s bite force, the researchers observed that even after skull scaling to adult model was performed, it still lagged a considerable amount behind its daddy’s biting force. This suggests that the T. rex underwent a change in feeding behaviour as it grew, leading to a non-linear jaw muscle growth.

“The power of the T. rex jaw has been a much debated topic over the years. Scientists only have the skeleton to work with, as muscle does not survive with the fossil, so we often have to rely on statistical analysis or qualitative comparisons to living animals, which differ greatly in size and shape from the giant enigmatic dinosaurs like T. rex. As these methods are somewhat indirect, it can be difficult to get an objective insight into how dinosaurs might have functioned and what they may or may not have been capable of in life,” said Dr Karl Bates, from the University of Liverpool’s Department of Musculoskeletal Biology.

The T. Rex is the most famous dinosaur in popular culture, however his fame is joined by much debate regarding his status. The T. Rex has been studied bone to bone for decades and decades, and a lot of theories have circulating around the dinosaur – whether he could run or just plod along, or most importantly whether he was a predator or a scavenger. Recent studies seem to point towards the predatory direction, and this latest bite analysis seems to add strength to the assumption.

“Our results show that the T. rex had an extremely powerful bite, making it one of the most dangerous predators to have roamed our planet. Its unique musculoskeletal system will continue to fascinate scientists for years to come,” Dr. Bates adds.

Despite its extremely powerful jaw muscles, the T. rex isn’t the most powerful bitter known to man – this honor goes to the fierce megalodon – a huge shark which could grow as large as 50 feet (16 meters) in length and weigh as much as 30 times that of the modern great white shark. Studies show that the bite force of the megalodon was three times more powerful than that of the T. rex.

The reseachers’ findings were  published in the journal Biology Letters.

source

Carnotaurus had puny arms, incredibly powerful tail

If you think that T-Rex had laughable front limbs, you’re in for a treat: even he would be amused by upon such puny arms. However, the shortcomings Carnotaurus had more than made up for its very muscular and powerful tail, which made it one of the fastest hunters to ever walk the face of the Earth.

Measuring over 8 meters long, Carnotaurus ruled South America, while T-Rex was ‘in charge’ of Asia and North America; the dinosaur had razor sharp teeth that fitted in quite nicely with its amazing hunting abilities. Tail bone fossils reveal that a particular muscle known as the caudofemoralis was attached by a tendon to the upper leg bones; when the tail moved, it gived a momentum to the back legs, which led to remarkable and fearsome strides – a feat it wouldn’t have been capable otherwise.

Brian Murphy from the University of Alberta conducted the study. His examination of the tail showed that along its length were pairs of tall rib-like bones that interlocked with the next pair in line. Using 3-D computer models, Persons recreated the tail muscles of Carnotaurus. He found that the unusual tail ribs supported a huge caudofemoralis muscle. The interlocked bone structure along the dinosaur’s tail did present one drawback: the tail was rigid, making it difficult for the hunter to make quick, fluid turns. Persons says that what Carnotaurus gave up in maneuverability, it made up for in straight ahead speed. For its size, Carnotaurus had the largest caudofemoralis muscle of any known animal, living or extinct.

Via io9

Everything you wanted to know about T Rex but were afraid to ask

T-Rex, or Tyrannosaurus Rex as it is more formally known is probably the most fascinating dinosaur to ever walk the face of the Earth, at least for most people. He became more famous however due to movies, rather than people taking interest in this fascinating predator. So this post is intended to provide you with as much info and pictures about T Rex as possible.

He was indeed a predator, and not a scavanger, as suggested by some researchers, but he wasn’t the biggest carnivore ever; as a matter of fact, he wasn’t even the biggest land predator ever, that honour going to Spinosaurus. An average T-Rex was about 12.5 meters long, 5 meters tall and weighed 6.8 metric tons. Still, size isn’t everything, even if you’re a dinosaur. Everything in Tyrannosaurus Rex is designed specifically for one thing: killing. Its huge head was balanced by a massive tail, and it featured a 1.2 meter jaw that could bite up to 230 kilograms in one bite – that’s about three average men.

The name, Tyrannosaurus means “tyrant lizard”, in Greek, and Rex means “king” in Latin – and for a good reason; the species managed to thrive while more and more competitors became extinct. However, not even the mighty T Rex could escape the mass extinction that took place 65 million years ago.

More than 30 specimens have been found, some of which are full skeletons, and even have proteins. The teeth are particularly interesting too: they were different in size and shape, with some teeth having a cone form (used for piercing flesh and dealing as much damage as possible), while others were more like “lethal bananas” rather than daggers. The longest T Rex tooth ever to be found measured 30 centimeters, making it the largest tooth in any carnivorous dinosaur ever to be found.

Unlike most dinosaurs, T-Rex had an unusual growth curve, increasing dramatically in weight after the age of 14. Still, his head has the S common to other related dinosaurs. It was historically described as a ‘living tripod’, with the body being at approximately 45 degrees from the vertical, walking on two legs and dragging the tail around, but modern representations show it with its body approximately parallel to the ground and tail extended behind the body to balance the head, which paleontologists believe to be much closer to reality.

The back legs of Tyrannosaurus Rex are extremely powerful, allowing it to carry massive weights, and run very fast on short distances. The only apparent weakness was its forearms, which are not even long enough to reach its mouth, but they probably could have been used for grabbing prey… or at least pieces of it. It was suggested at some point that T Rex was covered with feathers, or at least some protofeathers, but this theory was proven inaccurate.

All in all, despite not being the biggest, T-Rex was definitely the baddest around, and it definitely deserves the tyrant lizard king title. Hopefully, the media will not disrupt its image from now on, especially because there are still so many things we have yet to understand about this magnificant dinosaur.