Welcome to brain Stuff, a production of iHeart Radio. Hey They're brain Stuff, Lauren Vogelbaum Here. They lived about thirty million years apart and never set foot on the same continent. Yet Giganetosaurus carolini i is always getting compared to the world's most popular dinosaur, the beloved and well known Torannosaurus rex. Toranosaurus rex has been a media darling since arguably nineteen o six, when The New York Times called it the
prize fighter of antiquity. Named just one year prior, this big beast was already making a splash over at the American Museum of Natural History in Manhattan. Today, we know that an adult t Rex could stand twelve feet or about three and a half meters tall at the hip and measure forty feet or twelve meters long. As such, Torannosaurus was one of the largest predators to ever walk
the earth, But hold your horses. A handful of other meat eating dinos rivaled or possibly exceeded these creatures in size. Jiganosaurus belongs to this elite group, and it's part of a dinosauran mystery that's never been solved. T Rex and Jagonatosaurus were both representatives of the Therapoda clade, a clade being a group of organisms that includes a common ancestor species and all of its presumed descendants, hollow, boned and bipedal.
The therapods were and are a highly successful bunch. On the list of documented therapods, you'll find every carnivorous dinosaur ever discovered, quite a few plant gobbling species, and all birds living and extinct. The last non avian dinosaurs were wiped out at the close of the Cretaceous Period, an expanse of geologic time that lasted from a hundred forty five to sixty six million years ago. Its conclusion marked the end of the Mesozoic era, sometimes called the Age
of the Dinosaurs. Tyrannosaurus rex lived in North America during the Twilight of the Cretaceous, making its evolutionary debut around sixty eight million years before the present. Our buddy, Gigonatosaurus was the product of another time and a whole different land mass. Native to western Argentina, it came along much earlier in the Cretaceous, roughly ninety seven million years ago.
South America was a realm of giants. Back then, huge sauropods or long necked dinosaurs roamed the countryside, with some species stretching around fifty feet or fifteen meters long. Rounding out the local beasti area were crocodilians, early snakes, and beaked herbivores. No doubt Gigonatosaurus kept its neighbors on guard. That therapods discovery was first announced in by paleontologists rudolful Choria and Leonardo Salgado. In all the years since, we
have yet to find a complete skeleton. However, the backbones and tail vertebrate at art disposal suggest Gigonatosaurus was at least forty one ft or twelve and a half meters in length, so Gigonatosaurus might have been slightly longer than Tyrannosaurus. On the other hand, a paper published in argued that t Rex had a much heavier build. Using the circumference of its upper leg bone, Roger Benson and his colleagues calculated that a mature Giganetosaurus weighed about thirteen thousand, five
hundred pounds or about six thousand, one hundred kilos. The same technique put t Rex at a whopping seventeen thousand pounds or seven thousand, seven hundred kilos weight gaps are all well and good, but the jaws tell better stories. Anatomical evidence suggests that these two carnivores used very different methods to bring down their prey. The teeth of Tyrannosaurus were thick and sort of banana shaped and would have
excelled a crushing bone. In contrast, Giganetosaurus had tall, skinny teeth that looked an awful lot like recurved kitchen knives serrated on both sides. These pearly whites were housed inside a narrow snout. By the way, Giganetosaurus had a monstrous skull, soient estimate this noggin was around six ft or two meters long. Combine all of these features and you're looking at a therapod that probably killed by slicing ribbons of meat off of its unfortunate prey, as opposed to shattering bones.
Once bitten, a victim may have bled out while the carnivore lurked nearby. Giganetosaurus hails from one of the fossil records most intimidating families, the Cacara Donta swords. If you're into sharks, that name should ring a bell. Scientists called the Great white the car cardon Cacarius. Likewise, the word
cocardonto sword roughly means shark toothed lizard in Greek. Well we spoke by email with Steve Brusatti, a paleontologist at the University of Edinburgh who studied these remarkable therapods and happens to be a scientific advisor for the next Jurassic World movie. He said, the roster of Cacara donta sword fossils has expanded tremendously over the last decade as people have found new fossils all over the world, particularly in South americ in Africa, but also in Asia and Europe.
Most kacar dontosaurids, like Giganotosaurus were giant meat eating dinosaurs with deep jaws and sharp, thin, almost shark like teeth. They were the largest and most formidable predators in many ecosystems during the early to middle part of the Cretaceous before the rise of Tyrannosaurus. Indeed, t Rex itself had some puny forebears. The first members of its lineage were human sized predators that showed up around a hundred and
seventy million years ago. Giant Tyrannosaurus wouldn't start evolving until the late Cretaceous period, after the mighty cocar Donta saurids died out. Brussadi said that this changeover remains a mystery. We really don't know why it happened, and it's one of the biggest remaining mysteries of dinosaur evolution in my opinion. Today's episode was written by Mark Mancini and produced by Tyler Klang. For more on this and lots of other thunderous topics, visit has to Forks dot com. Rain Stuff
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