10 Hardy Facts About Euoplocephalus

Life in tyrannosaurid country forced Euoplocephalus to develop some extreme safety features. (You know you’re dealing with one tough customer when armor-plated eyelids are involved.) Here are 10 more things you might not know about this fascinating herbivore.

1. Its Terrifying Tail Club was Supported by Bony Tendons.

The far end of Euoplocephalus’ tail was basically a rigid hammer thanks to these rods. In action, powerful muscles near the tail’s more flexible base swung that half around with potentially bone-splintering force.

2. Euoplocephalus Probably Wasn’t the Sharpest Knife in the Drawer.

We’ll never know how intelligent an extinct animal truly was—after all, objectively assessing a live creature’s brain power is nearly impossible. Still, a popular tool called the “encephalization quotient” might help point us in the right direction. By measuring a given creature's brain mass, then dividing that number by whatever brain mass we'd expect an animal of that size to possess, we land at an EQ estimate for the beast in question. 

Supposedly, the brightest critters get the highest numbers. For the record, we self-aggrandizing humans have an average EQ of 5.28 while platypuses and their kin lag far behind at around 0.87. In 1979, paleontologist James Hopson tried to calculate an EQ for Euoplocephalus. His result: 0.52.

3. It Was a Pretty Decent Masticator.

Mammals totally trump reptiles in the chewing department. Since dinosaurs couldn’t move their lower jaws from side to side the way people do, most would have either swallowed foodstuff whole or mashed it up by slamming their teeth together in a straight, vertical motion. Euoplocephalus, on the other hand, had a more complicated technique: By pulling its lower jaw backwards, this dino’s pearly whites could tear apart its vegetarian entrees with ease.

4. Generally, Euoplocephalus Let Its Tail Club Hang Low.

Given the proportions of Euoplocephalus’ tail and hind legs, the tail, when being used for fighting, was likely suspended “just above the ground, neither dragging nor being greatly elevated.” At least, that’s what dino locomotion expert Walter P. Coombs Jr. concluded in 1995

5. Toy Manufacturers Keep Shortchanging Euoplocephalus.

For 56 million years, body armor was all the rage thanks to the ankylosaurid family. One could argue that, scientifically, Euoplocephalus is this brawny gang’s best-known genus due to an abundance of specimens—though many of these probably came from different dinosaurs (see below for more on that).

In a perfect world, Euoplocephalus would be a household name. Unfortunately, its bigger cousin Ankylosaurus keeps hogging the spotlight—there's a Godzilla villain named in its honor, it has an upcoming Jurassic World appearance, and plastic toys clearly based on Euoplocephalus are often mislabeled Ankylosaurus.

6. Euoplocephalus Had Some Weird Neck Armor ...

Several bony plates were fused together in an arch-shaped block that was draped over Euoplocephalus’ neck. Called a cervical half-ring, this odd structure can only be found in ankylosaurs.

7. … And Even Weirder Nasal Passages.

Get a whiff of this, folks: Apparently, inward breaths had to take a circuitous path from the dino’s nostrils to its lungs. Twisted Euoplocephalus nasal passages are so erratic-looking that they’ve even been compared to novelty crazy straws. Perhaps this convoluted mechanism evolved to help cool down the brain. Or maybe Euoplocephalus used its schnoz to produce deep, resonant sounds. Both explanations make sense.

8. Like Many Ankylosaurs, It Had a Really Wide Ribcage.

Generous midsections not only make Euoplocephalus and company really hard to draw, they also hint at a heavy-duty digestive system. Ankylosaur rib cages were almost as wide as their equally outrageous hips, leading paleontologists to suspect that the herbivores’ huge abdominal regions acted as massive fermentation chambers, made to break down the fibrous plants these guys ate. By the way, if this hunch is accurate, suffice it to say that you wouldn’t want to light a match near one. 

9. Euoplocephalus May Have Mated Feline-Style.

How did two enormous animals that were essentially legged tanks copulate? Ankylosaur specialist Ken Carpenter offered a decent hypothesis in his 2000 book Eggs, Nests, and Baby Dinosaurs: A Look at Dinosaur Reproduction. “[A] common method,” he writes, “might be for the female to squat on her forelimbs, raising her rear to the air (sort of like a house cat). In this position, with the tail off to one side, the cloaca is well exposed. The male could mount her from behind to one side and support himself with his forelimbs on her back.” For you visual learners, Carpenter drew a picture for you.

10. It Likely Wasn’t Quite as Successful as We’d Assumed.

Euoplocephalus was once something of an aberration. After its discovery in 1902, the animal went on to become North America’s most commonly-found ankylosaurid by a cozy margin. Moreover, there was only one species within this genus: Euoplocephalus tutus. E. tutus, it was thought, lived from 76 to 67 million years ago, an unusually long span by species standards.

Euoplocephalus was heavily revised in 2013 by then-Ph.D. student Victoria Arbour. As part of her doctoral research, Arbour took a good, hard look at every available specimen and concluded that, in actuality, four separate speciesScolosaurus cutleri, Anodontosaurus lambei, Dyoplosaurus acutosquamens, and Euoplocephalus tutus itself—had all been wrongly lumped together under the name E. tutus. Hence, she argues that good old Euoplocephalus really lasted a scant 2 million years. If you’ve got the time, check out "Who-oplocephalus? Euoplocephalus!" Arbour’s excellent, pun-tastic talk:

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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