10 Fun Facts About Deinonychus

We no longer see dinosaurs as the same oafish, tail-dragging monsters that trudged through King Kong (1933). Over the past 50 years, they’ve undergone an amazing scientific makeover—and if this shift in our perception could be traced back to a single breakthrough, it’d have to be the discovery of an athletic creature named Deinonychus antirrhopus.

1. Deinonychus Helped Revolutionize Dino Paleontology ...

Some odd-looking remains were discovered on a fossil-hunting trip through Montana in 1964. Yale paleontologist John Ostrom quickly deduced that these were the bones of a carnivorous dinosaur that belonged to the theropod suborder. He also realized that this new animal defied almost everything we thought we knew about the “terrible lizards.” This predator clearly wasn’t built for a sluggish, reptilian existence. Instead, its light frame, counterbalancing tail, and huge, hooked claws betrayed an active lifestyle. Perhaps it was even warm-blooded. Five years later, Ostrom released a paper that introduced the world to his game-changing dinosaur, which the scientist called Deinonychus, or “terrible claw.”

2. … And it Revived the Whole Dinosaur/Bird Idea.

Today, virtually all paleontologists recognize that birds are the descendants of dinosaurs. Back in 1970, however, this notion seemed outdated. Naturalists started wondering about a possible link during the mid-to-late 1800s, but the conclusion that birds actually evolved from dinosaurs quickly fell out of favor—until Ostrom came along. In short order, he noted many glaring similarities between Deinonychus’ arms and those belonging to an ancient, feathery critter known as Archaeopteryx, and the long-dormant concept once again took flight.

3. Deinonychus Inspired the Raptors of Jurassic Park.

An unfortunate naming mix-up has kept Deinonychus from getting the celebrity treatment it so richly warrants. In 1988, researcher Gregory S. Paul published a splendid book entitled Predatory Dinosaurs of the World: A Complete Illustrated Guide. At the time, he believed that Deinonychus antirrhopus was really a large, North American species of Velociraptor, an exclusively Asian genus, and his book uses the name Velociraptor antirrhopus instead.

Even then, however, the overwhelming majority of paleontologists strongly disagreed with this assessment. Deinonychus, they argued, was far too different from Velociraptor to be casually lumped together with it. For starters, the Old World dinosaur was only about 6 feet long and had a fairly narrow snout. In contrast, Deinonychus antirrhopus stretched over 11 feet from end to end and sported a much taller snout. Soon enough, Paul heeded their remarks and resumed calling a spade a spade and a Deinonychus a Deinonychus.

But Paul’s work left a big impact on novelist Michael Crichton, who almost certainly used Predatory Dinosaurs of the World as a reference while writing Jurassic Park. So his characters wound up fleeing from an animal that’s obviously modeled after Deinonychus—right down to its size and skull shape—but is called Velociraptor anyway. Stephen Spielberg followed suit, and the rest is pop culture history.

4. Deinonychus and its Kin Probably Weren’t Half as Smart as the Media Would Have You Believe.

Thanks to Jurassic Park, dromaeosaurs—also known as raptors—have been painted as super-intelligent killers whose IQs were supposedly on par with those of whales and primates. Don’t buy the hype. Though they do appear a bit brainier than your typical dinosaur, it’s impossible to figure out just how smart an extinct animal really was, and even liberal estimates put clever dinosaurs in the same league as ostriches and opossums.

5. Also, There’s no Concrete Evidence that They Hunted in Wolf-Like Packs.

Ostrom himself first suggested this in the '60s after finding the skeletons of three Deinonychus scattered around one Tenontosaurusa much larger herbivore. Case closed, right? Not so fast: Perhaps they were merely squabbling over carrion, Komodo dragon-style. Nowadays, you won’t find any nonmammalian carnivores that form complicated hunting groups. Usually, a disorganized mob works just as well. 

6. Deinonychus Had a Semi-Rigid Tail.

AStrangerintheAlps via Wikimedia Commons // CC BY-SA 3.0

Long, interweaving rods extended from most of its tail vertebrae, which made the appendage abnormally stiff. According to most experts, the dinosaur’s strange tail acted as a counterweight to the rest of its body. Hence, a running Deinonychus could have made sharp turns midstride by suddenly swinging that thing about.  

7. Its Dexterity Left a Lot to Be Desired.   

Listen up, humans: Never, ever take your opposable digits for granted! Deinonychus’ smaller cousin Bambiraptor—and, yes, the lil’ bugger was named after Disney’s wide-eyed deer—had one on each hand, meaning that it could grasp things with relative ease. Deinonychus wasn’t so lucky: Because none of its fingers worked this way, the animal had to pick up an object by squeezing it between its palms.

8. A Probable Deinonychus Egg Has Been Located.   

Certain dinosaurs had stomach ribs called gastralia. These bones (which crocodiles also possess) were situated in the belly, where they helped support vital organs. In 2006, researchers found a few Deinonychus gastralia nestled atop an incomplete fossil egg. Assuming that a Deinonychus actually laid this egg, the position of the ribs implies that one of its parents died while brooding on it like a hen.

9. Deinonychus Most Likely Kept its Arms Folded.  

Emily Willoughby via Wikimedia Commons // CC BY-SA 4.0

By and large, dromaeosaurs have been illustrated with their forelimbs dangling almost limply from their torsos. But in recent years, this portrayal has come under fire. That position would have been ungainly, and although Deinonychus, Bambiraptor, and company couldn’t bend their wrists as far as today’s birds can, they probably spent most of their time with each arm tucked up against the body anyway.

10. We May Have Been Underrating its Bite Force.

Depending on who you ask, Deinonychus either bit weakly or used more chomping power than a hungry hyena. One 2010 analysis of several Tenontosaurus bones laced with Deinonychus tooth marks concluded that in order to leave these punctures, the dino’s jaws had to have been as strong as a present-day alligator’s. But this study had its critics, who argued that Deinonychus’ slender skull didn’t leave room for jaw muscles large enough to cause such damage. Besides, it was plenty frightening without them.  

New LEGO Set Recreates Jurassic Park's Iconic Velociraptor Chase Scenes

Jurassic World: Fallen Kingdom, the fifth installment in the Jurassic Park franchise, is skulking into theaters on June 22. That makes now the perfect time to revisit the original film in LEGO form.

This LEGO set, spotted by Nerdist, depicts some of the most suspenseful scenes from the 1993 movie. There's the main computer room where Ariana Richards's Lex shows off her hacker skills while Alan Grant (Sam Neill) and Ellie Sattler (Laura Dern) struggle to keep a hungry dinosaur from barging in. Just like in the film, the door features a deadbolt lock that's velociraptor-proof (though, unfortunately for the characters, the detachable window is not). Other Easter eggs hidden in this part include a map of Isla Nublar and a screener saver of LEGO Dennis Nedry (Wayne Knight).

In the neighboring room, you'll find the cold storage unit where the dinosaur embryos are kept, along with the fake shaving cream can Nedry uses to steal them. The final section is the kitchen, where Tim (Joseph Mazzello) and Lex are stalked by the velociraptor. There's less room for them to hide in the LEGO version compared to the movie set, but there is at least one functioning cabinet for Lex to tuck herself into. Closer inspection reveals even more details from the film, like the lime-green Jello Lex is eating when the raptors first arrive and the step ladder the gang uses to escape into the air ducts during the final chase.

LEGO Jurassic Park set.

LEGO Jurassic Park set.

LEGO Jurassic Park set.

The Jurassic Park Velociraptor Chase set is currently available from the LEGO shop for $40.

[h/t Nerdist]

All images courtesy of LEGO.

Why Are There No More Dinosaurs?

WHY? is our attempt to answer all the questions every little kid asks. Do you have a question? Send it to

Actually, there are still dinosaurs: Birds! But let’s talk about that a little later. Scientists have found clues in rocks and fossils that tell us that by 65 million years ago, the climate (CLY-met), or usual weather, of the Earth had changed a lot, becoming cooler and drier. That was hard on the heat-loving dinosaurs. But that’s not why almost all of the dinosaurs became extinct, or disappeared forever. Scientists think a terrible event occurred that killed them off.

In 1991, scientists discovered a huge 110-mile-long crater, or hole, in the Gulf of Mexico. They think this crater was made by a giant, fiery, 6-mile-wide asteroid (AST-er-oyd) from space that smashed into the Earth about 65 million years ago. The impact was more powerful than any bomb we have ever known. Scientists believe this event killed most plant and animal life—including the dinosaurs. The asteroid probably caused shockwaves, earthquakes, fireballs, wildfires, and tidal, or really big, waves. It also sent huge amounts of dust and gas into the atmosphere, which is like a big blanket of air that surrounds the Earth. That was really bad for the planet.

The dust blocked sunlight, making the planet very cold and dark. Then, over time, the gases trapped heat, causing the Earth to get even hotter than it was before the asteroid hit. This change was deadly for most dinosaurs, and they became extinct. But birds survived. Many millions of years earlier, they had evolved (ee-VOL-ved), or changed slowly over time, from one group of dinosaurs. And when the dinosaurs disappeared, mammals diversified (die-VERSE-uh-fide), or changed, into many different kinds of animals—including us, many millions of years later. So the next time you see a bird swoop by, wave hello to the little flying dinosaur!    


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