Tag Archives: tyrannosaurus

Tyrannosaurus rex.

Largest T. rex skeleton ever found lived in Canada up to its early 30s

Researchers at the University of Alberta (UAlberta) have reported finding the world’s largest Tyrannosaurus rex and the largest dinosaur ever discovered in Canada — they named it “Scotty”.

Tyrannosaurus rex.

A T. rex skull (not Scotty’s).
Image credits Jill White.

The impressive skeleton spans 13 meters in length and, in true paleontologist fashion, was nicknamed for a celebratory bottle of scotch the night it was discovered. Scotty used to live in prehistoric Saskatchewan 66 million years ago. Judging from its leg bones, its discoverers estimate that it weighed some 8,800 kg while alive, making it bigger than any other carnivorous dinosaur whose fossil we’ve recovered.

King of kings

“This is the rex of rexes,” said Scott Persons, lead author of the study and a postdoctoral researcher in the Department of Biological Sciences at the UAlberta.

“There is considerable size variability among Tyrannosaurus. Some individuals were lankier than others and some were more robust. Scotty exemplifies the robust. Take careful measurements of its legs, hips, and even shoulder, and Scotty comes out a bit heftier than other T. rex specimens.”

The skeleton was first uncovered in 1991, when several paleontologists — including T. rex expert, UAlberta professor, and one of this study’s co-authors Phil Currie — were called in on the project. The bones were encased in hard sandstone, and it took the team over a decade to remove the bones from the stone without damaging them. Now, however, the researchers have been able to assemble and look at Scotty in its original shape.

Scotty’s size immediately made an impression on the team. It is the largest T. rex specimen, by both size and weight, that we have ever recovered. It is also, according to the team, the most senior dinosaur of the species that we have ever seen.

“Scotty is the oldest T. rex known,” Persons explains. “By which I mean, it would have had the most candles on its last birthday cake. You can get an idea of how old a dinosaur is by cutting into its bones and studying its growth patterns. Scotty is all old growth.”

“By Tyrannosaurus standards, it had an unusually long life. And it was a violent one. Riddled across the skeleton are pathologies — spots where scarred bone records large injuries.”

T. rexes tended to live very violent — and thus not very long — lives. Scotty, estimated to have been in its early 30s when it died, stands out as being quite old. It’s even more surprising that the dino reached this advanced age as its skeleton shows signs of broken ribs, an infected jaw, and a lot of battle scars — including, possibly, a bite from another T. rex on its tail.

“I think there will always be bigger discoveries to be made,” said Persons “But as of right now, this particular Tyrannosaurus is the largest terrestrial predator known to science.”

A new exhibit featuring the skeleton of Scotty is set to open at the Royal Saskatchewan Museum in May 2019.

The paper “An Older and Exceptionally Large Adult Specimen of Tyrannosaurus rex” has been published in the journal The Anatomical Record.

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.”


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.