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The Best Dinosaur in the JURASSIC WORLD Trailer Isn’t Actually a Dinosaur

Up until the dinosaurs died, a 50-foot long lizard was patrolling the seas for 27 million years. In Jurassic World, they are splashing park-goers like Shamu.

Descended from a major group of reptiles that returned to the sea, Mosasaurs were ferociousĀ oceanic and freshwater predators that quickly diversified and dominated the oceans during the Late Cretaceous period. The largest of these mosasaurs — Hainosaurus — could reach up to 50-feet long, and resembled a komodo dragon with flippers stuck on it. Mosasaurs had double-jointed jaws with flexible, snake-like heads, and they propelled their sometimes gigantic bodies with side-to-side motions like an anaconda or sea snake slipping through the water.

But they weren’t dinosaurs.

112614_Mosasaur_FossilYes, this was a real creature (and the eye does have bony rings in it).

During the last age of the dinosaurs, mosasaurs burst onto the aquatic scene as other dominant ocean lizards, Ichthyosaurs and Plesiosaurs (laparas for you pokemaniacs), met their demise. The mosasaurs, however, did not evolve from fully-aquatic ancestors. They are believed to be descended from within a family of semi-aquatic lizards called Aigialosauridae, though the fossil record is a bit spotty on the precise transition.

112614_Mosasaur_LineageThese marine lizards were more closely related to, well, modern lizards than dinosaurs (very simplified). Image: Arvind Pillai.

Unlike what we see in the Jurassic World trailer, these predators likely had forked tongues like modern snakes and lizards do. But the largest mosasaurs were indeed gigantic — 50-feet long and 15 tons in weight — though the family had a range of species that got as small as 3-feet long. Some were the size of a large dog, but with gigantic teeth and a flexible head and it would eat your dog. Mosasaurs did probably eat sharks too, even though prehistoric sharks could often turn the tables.


How much money would you pay to see a mosasaur water show? Like, all the money? Me too.

IMAGES: Arvind Pillai; Mosasaurus at Natural History Museum of Maastricht by Ghedoghedo

Don’t miss our breakdown of the Jurassic World trailer from yesterday’s Nerdist News!

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  1. Taylor says:

    I agree they made it too big to be accurate, but from what I know in this movie they genetically alter a lot of the dinosaurs, so maybe the scientists made it bigger on purpose? Idk, just a thought.

  2. B says:

    BTW The Velociraptor’s claw cited on the “D-Rex” is a hallux aka the (not so) bit toe which is like a dew claw on the T-Rex, Raptor, and many other theropods. 

    The Raptor’s large claw being the index toe (third tow in) on it’s foot.

    I am quite curious about the hands though, that seem to have at least three fingers! Did anyone else notice that the finger spacing may have suggested an opposable thumb? Or perhaps it was just the fore-shortened view of the claws playing tricks on my eyes.

  3. Alex says:

    You spelled Lapras wrong >:( get it right. You’re not a tru nerd. /sarcasmSeriously though you spelled it wrong. 

  4. Van says:

    Pretty sure you would have to pay me to go there. Just think about it a Jurassic park sea world with a giant sea monster on an island. What happens if they lose power. I mean it could happen right?
    Now just saying if it were to escape the only way guest get there is by boat . Right? How would you get off the island that is now the soul territory of a creature that eats a great white in one bite?
     Sure they can always fly off the island. But would the ocean ever be safe to go into again? 

  5. Rick says:

    I thought it was a Liopleurodon, an enormous pliosaur which grew upwards of eighty feet long and was the largest predator ever to have lived.

    • Josh says:

      The wikipedia article on Liopleurodon says that scientists currently think the 20-25 meter size shown in Walking With Dinosaurs is dubious (resulting from fragmentary skeletons) and they now generally think they grew to a maximum of 21 feet.

    • wessel says:

      I thought so too at first, but upon closer inspection(yes I’m that nerd) I think they are right about it being a mosasaur. It’s all in the flippers, Mosasaurs generally had small flippers, like the one in this trailer. Whereas Liopleurodon’s had enormous flippers. Also I think they basically took this water tank thing from the telltale game, which featured and it was a mosasaur there too.

  6. Logan says:

    Bcadren, I’m tired of people pretending the first one tried to stick to the known science and this one is getting away from it. The first one in no way did that and very much Hollywood’ed up the whole thing.

    They didn’t know most dinosaurs had feathers back then, sure. But velociraptors were actually very tiny and the dinosaurs they created were giant compared to the actual thing. Not to mention the “spitters” with the cobra hoods that project venom to blind their victims. That’s more ridiculous than making something larger than it really was.

    I loved Jurassic Park and don’t know if this movie will be nearly as good, but I’m tired of people pretending Jurassic Park didn’t do this kind of thing only because they like that movie.

    • Erin says:

      The original book was actually as accurate as it could be at the time it was written. The ‘Hollywooding up’ is to be expected from Hollywood, is it not? It no surprise to me this movie took so long to come out. I can’t imagine what Mr. Crichton would think of it.

      • April says:

        @Erin  Michael Crichton took some liberties.  His dilophosaurii are armed with venomous bites, and spit their saliva to blind prey.  His procompsognathus is also venomous, and is specifically said to have venom comparable to a cobra.  His hypsilophodons roam in trees.  His “Lost World” carcarodontosaurus has camouflage comparable to the mimic octopus.  Those are a few examples off of the top of my head.  I’d need to reread the books to potentially expand my list.

  7. Beth says:

    Let’s just hope that thing can’t breed or cruise lines will have more to worry about than rampant diarrhea! šŸ˜‰

  8. Scooby says:

    Here’s me thinking it was Predator X.

  9. Jess says:

    I was hoping Kyle would do a scientific breakdown of the trailer! Still, my inner six year old will disregard all scientific inaccuracies and plot holes because DINOSAURS!!!!

  10. guest says:

    Just short of selling my children if I had any. Thats howmuch I would pay to see such a creature. 

  11. C. says:

    It’s a movie.  

  12. Josh says:

    You should probably mention that the creature seen in the trailer in no way resembles the actual size of the real Mosasaur.  If we say that the trainer in that first photo is 5.5 feet tall, just the portion of the Mosasaur that is out of the water is 50 feet long. The things were also almost half tail and what’s out of the water doesn’t even get halfway to the second set of flippers.  So if what we see is a third of it, the rest would make the full thing around 150 feet long. Making it the largest creature ever to live on Earth.

    My opinion, unless we’re watching Mega-crock vs. Gateroid on Sy-Fi, what we’re seeing is forced perspective, that shark is actually only 2 feet long.

    • dan hagman says:

      Its a movie not a documentary.

      • Bcadren says:

        It’d similar be worth noting that new science says the lack of feathers on the raptors is wrong…and the original did try to stay with what was current science at the time, tho…this is…brushing away from that.

      • Josh says:

        But is it a Sharknado type movie or a Jurassic Park type movie?

    • Arlizz says:

      I cringed when I saw that as well. Presumably the great white is like 16-20 feet. It’s all hype and so stupid. 50 feet is around how long most of these monsters would have gotten, including Hainosaurus, Tylosaurus, and Mosasaurus.

    • James says:

      Maybe they were meant to write 50 meters, rather than feet? This would make more sense.