Deinonychus: The Dinosaur That Sparked a Renaissance

beliefs regarding dinosaur metabolic rates came into question awhere. Previously, our best scientific guess was that dinosaurs would have been big, cold blooded lizards and therefore mostly slow and lethargic. During this time, we started to understand that some might have been active hunters. And it was all thanks to one species unearthed in Montana that also became the basis of

Jurassic parks velociraptors. Today, let's talk about Diynonicus. Back in nineteen thirty one, while exploring southern Montana, paleontologist Barnum Brown found the incomplete skeleton of a dinosaur that would have measured some eight feet that's two and a half meters in length. It was clearly a theropod, a member of the same group as Alosaurus and Tyrannosaurus rex. This one had an agile build. Not only was it light boned, but there were long, wiry extensions on the tail vertebra.

Brown guessed the stiffened the appendage as a whole, helping the tail act as a better counterweight to the rest of the body. Though Brown planned to write a manuscript about this intriguing new dinosaur, he was unable to finish before his death in nineteen sixty three, But in his later years, Brown showed the skeleton to a young researcher named John Ostrom. August of nineteen sixty four found Ostrom hunting for early Cretaceous dinosaurs around Bridger, Montana. Under the

summer sun. He and a colleague discovered the clawed hand of a theropod peeking out of the earth. Then a foot turned up, so did thousands of other bones. Ostrom soon realized he was dealing with the same species that Brown had unearthed decades earlier. He named the creature Dinonicus

anti rappus. At the time, he had recovered the bodies of four individuals at a single Montana quarry, all lying in close proximity to some bones from t Nantosaurus, a plant eating dinosaur with a beak and a long tail that would have grown to over twice the size of a Dinonicus, possibly over five times the size. Dinonicus means terrible claw. This was inspired by the huge curved claws that topped the second toe of each foot. To Ostroum,

this was a revelation. Dinonicus would have held these claws off the ground as it walked, standing sort of perched with light bones, battle ready and athletic. Historically, dinosaurs were thought to be plotting beasts, Buticus contradicted this assumption. Ostrom wrote in nineteen sixty nine, it must have been a fleet footed, highly predacious, extremely agile, and very active animal,

sensitive to many stimuli and quick in its responses. Ostrom's work on Diynonicus was a catalyst for the dinosaur renaissance, but you don't have to be a science enthusiast or a history buff to appreciate its impact. The famous, though fictionalized velociraptors from Jurassic Park were based on Dinonicus. Don't get us wrong, there was an actual theropod named Velociraptor that lived in Central Asia some seventy five to seventy

one million years ago. However, it was way smaller than the creatures shown in the popular movies, which can look a grown man in the eye. The real Velociraptor stood just twenty eight inches tall at the hip. That's seventy two centimeters, closer to the size of a wild turkey, just with the longer body and more weight on its bones.

Dinonicus wasn't all that big either, but would have stood about thirty eight inches tall at the hip or one meter, and could grow more than eleven feet long that's three and the third meters, so it would have been staring into sam Nil's chest, not his eyes. Both Velociraptor and Dinonicus belonged to the same family of bear pods, the dromiosaurs, found in Eurasia, Africa, and the Americas. The dromiosaurs had

knife like teeth, big skulls, and long limbs. At least some probably all of them had feathers to boot, but let's revisit those terrible claws. Dinonicus was not unique in having an enlarged talon on the second toe of each foot. It was a standard dromiosaur feature, said toes were hyper extensible, they could be pulled back into an almost vertical position. Besides keeping the claw tips sharp, this trait gave them

a wide arc of motion. Ostrum Dgennonicus leaping through the air, slashing wildly with the curved daggers on its flexible toes. But more recent modeling has painted a different picture. In twenty nineteen, paleontologist Peter J. Bishop published a three D Dinonicus hind limb reconstruction. According to his simulations, the toe claws couldn't exert very much force. They were probably better

at grasping prey than disemboweling it. And remember the long rods on Dinonicus's tail vertebra, Velociraptor, uteriraptor and other dromiosaurs had those two experts think that they made all but the base of the tail very rigid. That sort of like a tightrope walker's long pole. It would have kept

the animal upright and balanced while moving. One velociraptor fossil, discovered in nineteen ninety nine, with its tail in an s curve, may challenge that view, though it's hard to say whether the shape was the result of motion during life or the settling of the bones after death. Speaking of fossils, let's go back to Ostrum's find a four carnivorous Dynonicus in close proximity to a herbivorous but much larger to Nontosaurus. It got him thinking, he wrote in

nineteen sixty nine. The multiple remains suggest that Dinonicus may have been gregarious and hunted in packs. Author Michael Crichton ran with the idea. His original Jurassic Park novel published in nineteen ninety, which was the basis for Steven Spielberg's nineteen ninety three movie adaptation, describes the raptors attacking their prey in organized packs, working together to bring down dinosaurs and humans alike. Yet scientists have cause for skepticism. Habitual

strategic pack hunting is quite rare among modern animals. Perhaps Dinonicus and other dromiosaurs were loners for the most part, but went into spontaneous group feeding frenzies every now and then. After all, that's how modern komodo dragons roll. However, some birds, the closest living relative of dinosaurs, have been observed hunting in pairs, like peregrine falcons and Harris's hawks of the American Southwest coordinate in groups of five, communicating through movements

and converging on prey from multiple angles. So maybe Crichton's raptors and Prehistory's dromosaurs hunting like this isn't too far fetched after all. Today's episode is based on the article how Dynonicus Upended the way we look at Dinosaurs on how stuffworks dot com, written by Mark Mancini. Brainstuff is production of iHeartRadio in partnership with how stuffworks dot Com.

It is produced by Tyler Klang. Four more podcasts from my heart Radio visit the iHeartRadio app, Apple Podcasts, or wherever you listen to your favorite shows.