Speaker 1: Welcome to Brainstuff, a production of iHeartRadio, Hey Brainstuff Lauren
Speaker 1: Voleebaum here. The science fiction film Jurassic Park from nineteen
Speaker 1: ninety three didn't just bring dinosaurs back to the forefront
Speaker 1: of pop culture consciousness, It actually inspired some science of
Speaker 1: its own. The film establishes early on that the Tyrannosaurus
Speaker 1: rex's vision is based on movement, so the characters can
Speaker 1: escape its notice if they can stand very still. That
Speaker 1: got computer scientist Kent Stevens thinking. In two thousand and six,
Speaker 1: he compared the eye socket orientation of several carnivorous dinos.
Speaker 1: T Rex included. When you look straight ahead, the area
Speaker 1: that both eyes can see simultaneously is called your binocular
Speaker 1: field of view. The wider your binocular field of view,
Speaker 1: the better your depth perception. So how did t Rex
Speaker 1: measure up? According to Stephen's finding, these dinosaurs possessed an
Speaker 1: impressive binocular field of view up to fifty five degrees wide.
Speaker 1: Not even the hawks we have today can match this figure,
Speaker 1: meaning Tyrannosaurus probably had great depth perception and division in general.
Speaker 1: Of course, people were fascinated by the t rex long
Speaker 1: before Jurassic Park came out. The paleontologist Henry Fairfield Osborne
Speaker 1: coined the dinosaur's name in nineteen oh five, derived from
Speaker 1: Latin and Greek Tyrannosaurus rex means tyrant lizard king. Osborne
Speaker 1: named the species on the basis of an incomplete skeleton
Speaker 1: found by the legendary fossil hunter Barnum Brown at a
Speaker 1: Montana dig site in nineteen oh two. Two years before that,
Speaker 1: Brown had discovered another carnivorous dinosaurs remains in eastern Wyoming.
Speaker 1: A close inspection would prove it belonged to the same species,
Speaker 1: although Osborne didn't recognize that at first. Osbourne's workplace, the
Speaker 1: American Museum of now History in New York City, eventually
Speaker 1: mounted one of Brown's t Rex specimens in nineteen fifteen.
Speaker 1: Then the film industry stepped in. A stop motion animator
Speaker 1: Willis O'Brien brought the beast to life for nineteen eighteen's
Speaker 1: The Ghost of Slumber Mountain and Early Dinosaur Flick. And
Speaker 1: t Rex has stayed in the public eye ever since.
Speaker 1: As science historian Jane Davidson once noted, it's the animal
Speaker 1: that probably springs to mind when most of us hear
Speaker 1: the word dinosaur. Remains of around fifty individual Tyrannosaurus have
Speaker 1: been found in western North America. These range from isolated
Speaker 1: backbones to almost full skeletons claws down. The most complete
Speaker 1: t Rex yet discovered is Sue, a beautiful find from
Speaker 1: South Dakota. This celebrity skeleton is now on display at
Speaker 1: the Chicago Field Museum. A Scientists have identified three hundred
Speaker 1: and eighty bones that full grown Tyrannosaurus would have possessed.
Speaker 1: Siou contains two hundred and fifty of these and is
Speaker 1: about ninety percent complete by bulk of bones. Sue is
Speaker 1: also one of the bigger skeletons on record. A t
Speaker 1: Rex could grow to a hip height of roughly twelve
Speaker 1: feet that's three point six meters, and could be forty
Speaker 1: feet in length that's twelve meters. The skull alone is
Speaker 1: over four feet long in large adults that's about one
Speaker 1: point two meters. Only a couple known species of dinosaurs
Speaker 1: may have been bigger. Gigantosaurus, a predatory dinosaur native to
Speaker 1: what's now South America, might have been a midge longer
Speaker 1: than t Rex, a couple extra feet from nose to tail,
Speaker 1: and the fin backed Spinosaurus from what's now Africa could
Speaker 1: have been over fifty two feet or sixteen meters long.
Speaker 1: Guessing any dinosaur's weight is not an easy task because
Speaker 1: generally speaking, their fossilized bones are what we have to
Speaker 1: go on, and that doesn't tell us very much about
Speaker 1: how filled out they might have been. I mean, if
Speaker 1: you had to guess that what a penguin looked like
Speaker 1: based just on bones, you might never make the jump
Speaker 1: to the plump, well insulated bird. But by one calculation,
Speaker 1: a full grown t Rex would have pushed some seventeen
Speaker 1: thousand pounds that's about seven thousand, seven hundred kilos. At
Speaker 1: that size, Tyrannosaurus may have been heavier than Gigantosaurus or Spinosaurus.
Speaker 1: All three of these creatures actually belonged to the same group,
Speaker 1: a huge and diverse array of dinosaurs known as the theropods.
Speaker 1: Tyrannosaurus was part of a subgroup known as the tyrannosauroids.
Speaker 1: T Rex was the largest and one of the last.
Speaker 1: This subgroup first appeared in what's now Eurasia one hundred
Speaker 1: and seventy million years ago during Earth's Jurassic Period. These
Speaker 1: critters started small. An early species was only about the
Speaker 1: size of an adult human being. Geologically speaking, t Rex
Speaker 1: had a brief rain. The fossils this giant left behind
Speaker 1: range from sixty eight to sixty five and a half
Speaker 1: million years of age, so Tyrannosaurus was around to see
Speaker 1: the last days of the Cretaceous period, which ended with
Speaker 1: a mass extinction event. Birds, which are modern therapods, were
Speaker 1: the only dinosaurs to survive this ordeal. At some point,
Speaker 1: the tyrannosaurids entered what's now North America. No t Rex
Speaker 1: remains have ever been found outside of this continent, but
Speaker 1: a twenty sixteen paper speculates that the species could have
Speaker 1: originated in Asia and later spread to the Americas. In
Speaker 1: other words, perhaps Tyrannosaurus rex was an invasive species A
Speaker 1: Judging by the bone microstructure evidence, it would have taken
Speaker 1: to Tyrannosaurus twenty years or so to attain its maximum size.
Speaker 1: Maturity came with some lifestyle changes. Adult t Rex had thick,
Speaker 1: bananas shaped teeth, rigid skulls, and seriously powerful jaw muscles.
Speaker 1: Those attributes gave the dinosaurs a punishing bite force of
Speaker 1: around seven tons a, meaning that like hyenas, mature Trannosaurus
Speaker 1: or consummate bone crushers. On the other hand, juvenile t
Speaker 1: rex had narrow blade like teeth and weaker jaws, so
Speaker 1: instead of ripping prey apart and eating them pretty much whole,
Speaker 1: the youngsters probably specialized in slicing meat off of prey. Proportionally,
Speaker 1: adolescent t rex had longer arms and legs than their
Speaker 1: parents did. The forelimbs on an adult trannosaurus were only
Speaker 1: about three feet long that's around a meter, which looked
Speaker 1: kind of puny when you take their total body size
Speaker 1: into account. Nobody knows what the function of these forelimbs was.
Speaker 1: Maybe the pendages were hooks used to grasp struggling prey,
Speaker 1: or maybe they helped the dinosaurs hang on to their
Speaker 1: partners during intercourse. Their hind limbs were huge and powerful,
Speaker 1: but according to biomechanical research published in twenty seventeen, t
Speaker 1: rex legs weren't built for running. Instead, the dinosaur was
Speaker 1: more of a speed walker, astriding across the prehistoric countryside
Speaker 1: up to around twelve miles an hour that's nineteen kilometers
Speaker 1: an hour. They were not picky about their meals, though
Speaker 1: bitemarks attributed to this carnivore have been found on the
Speaker 1: bones of triceratops on duck billed plant eaters called pattersaurids,
Speaker 1: and even other Tyrannosaurus skeletons. Yes, friends, the tyrant lizard
Speaker 1: king probably ate its own kind. Also, on top of
Speaker 1: being a sharp eyed predator, Tyrannosaurus had a keen sense
Speaker 1: of smell, as is evidenced by the contours of its
Speaker 1: brain cavity. Today's episode is based on the article Tyrannosaurus
Speaker 1: Rex was the Tyrant Lizard King on housdifforks dot com,
Speaker 1: written by Mark Mancini. The brain Stuff is production of
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Speaker 1: by Tyler Kuang. Four more podcasts my heart Radio, visit
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