North Carolina Museum of Natural Sciences, Flickr // CC BY-NC-ND 2.0
North Carolina Museum of Natural Sciences, Flickr // CC BY-NC-ND 2.0

10 Ridged Facts About Acrocanthosaurus

North Carolina Museum of Natural Sciences, Flickr // CC BY-NC-ND 2.0
North Carolina Museum of Natural Sciences, Flickr // CC BY-NC-ND 2.0

This intimidating predator would look great on the big screen. Ahem, Steven Spielberg...

1. Acrocanthosaurus is the Official State Dinosaur of Oklahoma.

Acrocanthosaurus was discovered in Oklahoma’s Atoka County in the 1940s, and in 2006, it was declared the state’s official dinosaur—even though it already had a state fossil (another big carnivore named Saurophaganax). 

2. It Wasn’t Much Smaller than T. Rex.

While there aren't any complete specimens, most paleontologists estimate that a fully-grown Acrocanthosaurus would have been around 35 to 38 feet long. By comparison, Tyrannosaurus rex could reach about 40 feet. Both rank among the biggest meat-eating dinosaurs ever found.

3. Those Arms Might Have Helped it Ensnare Prey.

According to one 2006 studyAcrocanthosaurus’ forelimbs had a very limited range of motion. Still, despite that shortcoming, analysis revealed that the arms would have been quite adept at pulling things toward the animal's torso. Perhaps Acrocanthosaurus came up to victims from behind, sank its claws into them, and held on tight while chomping like mad.

4. Acrocanthosaurus Didn’t Keep its Chin Up.  

A 2005 computer simulation found that, given the shape of its inner ear (which helps creatures keep balanced), Acrocanthosaurus habitually let the tip of its snout point 25 degrees downward rather than straight ahead. 

5. The Dinosaur Might Have Stalked Maryland.

Though far better remains are known from Oklahoma and Texas, Acrocanthosaurus-like teeth have been found in the Old Line State.

6. A Similar-Looking Dinosaur Lived in England.

Becklespinax was 16 feet long and lived in the UK from 142 to 132 million years ago. Its name references some long spines that protruded from its vertebrae—much like the ones we see on Acrocanthosaurus. The two are widely thought to be relatives.

7. Many Footprints Have Been Attributed to Acrocanthosaurus.

Dinosaur Valley State Park in Glen Rose, Texas is loaded with 112-million-year-old fossilized track ways, most of which were probably made by passing Acrocanthosaurus. Some especially cool prints even hint at a prehistoric battle: While exploring the area in the ‘40s, explorer Roland T. Bird noticed a set of theropod tracks running parallel to some that were left by a sauropod. At one point, the predator appears to have broken stride and taken two consecutive right steps.

Why would it do this? Maybe the carnivorous theropod had latched on to the much bigger, long-necked herbivore. But the sauropod’s tracks show no change in spacing or direction—so if this particular animal was indeed under attack, it was weirdly relaxed about it.

8. The Animal Has Proven Very Difficult to Classify.

Acrocanthosaurus has been viewed as a close cousin of Allosaurusa North American predator that died out long before the ridge-backed dino came along. It’s also been lumped closer to a humongous carnivore from Africa known as Carcharodontosaurus. Thankfully, the water got slightly less murky in 2011. By comparing and contrasting several anatomical features, including the brain cavity, paleontologists Drew R. Eddy and Julia A. Clarke found that while Acrocanthosaurus definitely shared a common ancestor with Allosaurus, the dinosaur really belongs to Carcharodontosaurus’ family.

9. Acrocanthosaurus Had Plenty of Dietary Options.

One hundred and twenty-five million years ago, this massive carnivore shared its range with such sauropods as Astrodon and the 60-foot-tall Sauroposideon. A beaked, long-tailed plant-eater called Tenontosaurus was also available.

10. The North Carolina State Museum of Natural Science Once Paid $3 Million for One.

North Carolina Museum of Natural Sciences, Flickr// CC BY-NC-ND 2.0

Over the past 25 years, dinosaur skeletons have gotten absurdly expensive. In 1997, the Chicago Field Museum—backed by corporate sponsors—bought Sue, a T. rex skeleton that's 90 percent complete, for $8.36 million at auction. Shortly thereafter, the North Carolina State Museum of Natural Science found itself shelling out $3 million to secure a handsome Acrocanthosaurus from southern Oklahoma

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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