Wednesday, May 29, 2013

Jurassic Park’s Velociraptor is NOT Deinonychus: Making Brian Switek's Fanboy Hypothesis Extinct!

I just finished reading Brian Switek's new book "My Beloved Brontosaurus"; it's a pretty good book that gives a good overview of how much dinosaur paleontology has changed in the last 40 years. Unfortunately he struck a sour note with me on page 121.

Here he claims that Michael Crichton in Jurassic Park changed the name of Deinonychus to Velociraptor because Velociraptor was too small to be threatening. He claims the name change was due to Greg Paul classified Deinonychus and Velociraptor in the same genus. 

Ugh! I have been trying to squash that fanboy rumor for years. It is simply not so and reading the book they are supposedly fans of would easily show that this idea is incorrect. Oh and Spielberg’s movie is irrelevant as it omits the very background dialog that identifies the raptors in question. And besides we are talking about Crichton not Speilberg.

The simple fact of the matter is that the Greg Paul’s classification is irrelevant. Yes Paul classified Deinonychus in the same genus as Velociraptor but they were still different species. Even worse for Switek (and the fanboys) the novel actually says the animals cloned for the Park were cloned from DNA found in Mongolia and Deinonychus is a North American genus!

But first let’s see what the novel says about Deinonychus.

"What do you know about Velociraptor?" Grant asked Tim. He was just making conversation.

"It's a small carnivore that hunted in packs, like Deinonychus," Tim said.

"That's right," Grant said, "although Deinonychus is now considered one of the velociraptors."

This is from the first edition of the book (which I own) and it is omitted in more recent reprintings. With it gone the only other Deinonychus in the book is when Grant mentions the digging up a hatchling antirrhopus in Montana.

Note that Grant does not say Deinonychus is the same genus as Velociraptor. He says velociraptors, as in the animal group, and indeed in the 1980's Velociraptor and Deinonychus were placed in the same subfamily - the Velociraptorinae. Note that books in the 1970s placed Deinonychus in the subfamily Dromaeosaurinae so it's classification had indeed recently been changed. So Grant was right.

The movie version of JP's 'Velociraptor',  No doubt the designers modeled this animal on Deinonychus simply because that genus was (and still is) better known to the public than any other dromaeosaur.

But what about Crichton's "Velociraptor"? Surly they have to be Deinonychus (or the fandom's other favorite candidate, Utahraptor) due to their size? Sorry folks the book especially says that the scientists assumed the animal was Velociraptor becase the DNA came from Mongolia. Both Deinonychus and Utahraptor came from the United States. Even worse, Utahraptor was not even discovered until the movie was finished much less the book! But Crichton’s giant raptor was not something from his imagination. His giant “Velociraptor” is a stroke of Fridge Brilliance not a made up monster.

Crichton did indeed get his idea from Gregory S. Paul’s ‘Predatory Dinosaurs of the World’ but the idea was not a name change. On page 366 of Paul’s book can be found the following…

Also at the AMNH is a hyper-extendable toe bone from the late Cretaceous of Mongolia that looks like a Velociraptor somewhat bigger than V. antirrhopus.

In other words the scientists at Jurassic Park (not Crichton) made a mistake. At the time the Park was built (supposedly in the mid 1980’s according to the book) the only velociraptorine known from Mongolia was Velociraptor mongoliensis so when a raptor hatched out of an egg infused with Mongolian DNA they assumed the animal was a Velociraptor. That’s why the scientists were dismayed when the animals became so much larger and more vicious than one would assume from the fossils. They probably thought modern food was the culprit as animals in captivity often get larger than their wild counterparts due to better nutrition. This illustrated the callous disregard the Jurassic Park scientists gave their project. Note that Crichton points out several similar assuptions made by the JP scientists. Among these assuptions are a Stegosaurus (Triceratops in the movie) being poisoned after eating modern plants and their identification of Coelurus  as a herbivorous dinosaur!

So what was this animal the Jurassic Park scientist really cloned? Well at the time no one knew. Though the first bones were discovered in the 1980s the animal itself was not named or described until 1999. The animal is now called Achillobator giganticus. This animal from the Bayan Shireh formation of Mongolia inhabited the same desert scrub habitat that would be roamed by V. mongoliensis 15 million years later. It was some 16.5 feet long and (like the JP raptors) was once thought to be six feet tall until new findings showed it had short, squat, legs like a dodo bird. So while Crichton's giant Mongolian raptor was real the cheetah-like speed attributed to it by the movies was not.

Just for fun let’s compare silhouettes of the various raptors claimed to be the ones in Jurassic Park. The JP raptor is from the official McDonald's cup and even though it is rearing (rather than in a neutral posture) Achillobator is still the only animal of the correct size.

Jurassic Park raptor from an official JP cup distributed by McDonnalds. 

 Dinos4Ever the JPLegacy Moderator double checked these facts when I gave them and had to come to the same conclusion. Even the Jurassic Park Wiki agrees with me. The book speaks for itself, the raptors in Jurassic Park are NOT Deinonychus.

1. It's not the size of the real V. mongoliensis, because the true Velociraptor is a third of the size of the Raptors in the novel.
2. It's not Deinonychus "Velociraptor" antirrhopus, because the true Deinonychus is not only half the size of the novel Raptors, but does not originate from Mongolian or Chinese rock as Achillobator or Velociraptor does.
3. That leaves only one real contender: Achillobator. The size matches up; the location matches up. It's Achillobator.

Jurassic Park's raptors are not Deinonychus, Utahraptor, or even Velociraptor, they are Achillobator. Crichton and Paul knew what they were talking about even though the animal wasn’t even named yet. No wonder Jurassic Park failed, the poor scientists literally had no idea what they had cloned.

Charles R. Knights Dryptosaurus, the original leaping lizard and origin of the bounding raptor cliche'.


Crichton, Michael. 1990. Jurassic Park. Alfred A. Knopf; 1st edition. New York. New York.

Dinos4Ever. 2012. The True Identity of the Novel Raptors. Jurassic Park Legacy.

Jurassic Park Wiki. Velociraptor (Novel Cannon)

Martyniuk, Matthew P. 2012. A Field Guide to Mesozoic Birds. Pan Aves Publisher. Vernon, New Jersey.

Maryniuk, Matthew P. 2011. Waddle, _Achillobator_, Waddle!
Paul, Gregory S, 1988. Predatory Dinosaurs of the World. New York Academy of Science, Simon & Schuster Inc. New York, New York.

 O'Regan, Hannah J and Andrew C. Kitchener. 2005. The Effects of Captivity on the Morphology of Captive, Domesticated and Feral Mammals. Blackwell Publishing LtdOxford.

Switek, Brian, 2013. My Beloved Brontosaurus. Scientific American. New York, New York.


  1. Then why were they that fast??? That's more in line with Deinonychus.

  2. They were fast in the book and movie because at the time Jurassic Park was written all velociraptorines, including Achillobator were thought to be fast. Later finds showed that they were not. The book raptors also had scales something later finds have disproved. Science marches on.

    Besides Deinonychus is a North American genus not Asian as pointed out in the article. In any case the book InGen mutated the dinosaurs with the DNA of other species (not just frogs as in the movie) so maybe they added some cheetah genes? That's my 'in universe' explanation anyway.

  3. Back to this:

    While dromaeosaurs weren't the fastest theropods they are still fast compared to people.