jurassic park wikia
jurassic park wikia

6 Amazing Mosasaur Facts to Prepare You For Jurassic World

jurassic park wikia
jurassic park wikia

Meet Mosasaurus, a gigantic carnivore that swam seas around the globe 80 million to 66 million years ago. On June 12, you can see one doing its best Shamu impression in Jurassic World.

Few people on earth know more about the amazing mosasaur family than Michael J. Everhart, who’s been collecting marine fossils for decades. A celebrated paleontologist, he serves as an adjunct curator at the Sternberg Museum of Natural History in Hays, Kans. Between digs, Everhart manages Oceans of Kansas, which spawned a companion book in 2005. Everhart recently spoke to mental_floss about key mosasaur characteristics.

1. The Biggest Mosasaurs Were Longer Than T. rex.

Though we haven’t yet found any complete specimens, Everhart argues that both Mosasaurus and Tylosaurus (a North American cousin) probably “reached lengths of 14 to 15 meters,” or about 46–50 feet. Though Tyrannosaurus was much heavier, it maxed out at around 40 feet from nose to tail. At 60 feet long, the captive in Jurassic World surpasses even the wildest mosasaur size estimates.

Not all mosasaurs were giants. In real life, some species would have looked dwarfish beside an average American alligator. Fully grown Carinodens belgicus, for example, were likely a mere 6.5 feet long.

2. Mosasaur Jaws Are Pretty Interesting/Terrifying.

Look closely at this Jurassic World poster and you’ll see a Mosasaurus complete with two extra rows of teeth inside its maw. Did some Hollywood concept artist make these up to help the thing look scarier? Actually, no. Gripping food underwater would have been a challenge for mosasaurs. Luckily, like present-day snakes, they had a toothy secret weapon: pterygoid ("flanged") teeth, which were anchored to bones in the roof of the mouth. These made the job of handling—and swallowing—prey a whole lot easier. But, as Everhart points out, mosasaur teeth “were embedded in the fleshy tissue of their gums... [and] not nearly as visible as portrayed” in the movie.

3. Snakes and Monitor Lizards Are Their Closest Living Relatives.

Like their mosasaur relatives, snakes have extra teeth. The extinct reptiles were also closely akin to monitor lizards such as the Komodo dragon. Perhaps mosasaurs had forked, flickering tongues like their modern brethren. Unfortunately, because soft tissues seldom fossilize, we may never know for sure.

4. Mosasaurs Gave Birth to Live Young.

Everhart estimates that a 50-foot mosasaur would have weighed around 5000 kg (5.5 tons). Something that big would have really struggled to pull itself ashore to give birth. So like many oceanic animals, it gave birth beneath the waves.

We know this thanks to a Plioplatecarpus specimen. The midsize animal was found in both hemispheres' oceans from 83 to 71 million years ago. The “mother mosasaur,” which was discovered in South Dakota, shed some light on how these creatures came into the world: Scattered around the gravid (or pregnant) reptile’s body were the remains of her unborn young.

5. Just Before Dying Off, the Mosasaur Family Really Diversified.


Mosasaurs were wildly successful. Their fossils have been found on every continent, even Antarctica. And during the last 25 million years of the family’s existence, strange new varieties began to emerge. While more traditional mosasaurs dined on fish, squids, and smaller reptiles in the open ocean, a few latecomers carved out vastly different niches. Consider Globidens, which evolved rounded teeth designed for crushing hard shells. Later, the heavily built Goronyosaurus (whose skull almost looks like it was stolen from some poor crocodile) invaded African rivers. And then there is the narrow-snouted Plotosaurus with its weird, fish-like build—the potential hallmark of a streamlined, high-speed lifestyle.

6. Jurassic World takes liberties with its Mosasaurus.

For starters, Ingen’s Mosasaurus seems awfully acrobatic. “It’s not a killer whale,” Everhart says. This “tail-wagging” creature, he explains, simply wasn’t “fast enough in the water to do the kinds of jumps that are shown in the movie.” Also, the oversized specimen would probably surpass 6 tons in weight. “[That] is a lot of mass to try to shoot straight up out of a relatively small and shallow captivity pool,” Everhart says.

Everhart also takes issue with how the trailer released on April 20 portrays Mosasaurus flippers in action. “Their paddles would be held tightly against the body while swimming—watch a crocodile swim—not fluttering around creating drag,” he says. Theoretically, the appendages were used to help stabilize the animal. But the film shows them actively propelling it forward.

One other inaccuracy: The beast’s rough, croc-like hide. Real mosasaurs were relatively smooth skinned and covered with tiny scales, Everhart says.

Still, such exaggerations are par for the course. Whenever Hollywood tries to put prehistoric life on the silver screen, tweaks are always made to ensure the creatures are as cinematic and entertaining as possible. At the very least, Jurassic World already has people buzzing about mosasaurs, a group that deserves way more time in the spotlight.

Big Questions
What's the Difference Between Gophers and Groundhogs?
Gopher or groundhog? (If you chose gopher, you're correct.)
Gopher or groundhog? (If you chose gopher, you're correct.)

Gophers and groundhogs. Groundhogs and gophers. They're both deceptively cuddly woodland rodents that scurry through underground tunnels and chow down on plants. But whether you're a nature nerd, a Golden Gophers football fan, or planning a pre-spring trip to Punxsutawney, Pennsylvania, you might want to know the difference between groundhogs and gophers.

Despite their similar appearances and burrowing habits, groundhogs and gophers don't have a whole lot in common—they don't even belong to the same family. For example, gophers belong to the family Geomyidae, a group that includes pocket gophers (sometimes referred to as "true" gophers), kangaroo rats, and pocket mice.

Groundhogs, meanwhile, are members of the Sciuridae (meaning shadow-tail) family and belong to the genus Marmota. Marmots are diurnal ground squirrels, Daniel Blumstein, a UCLA biologist and marmot expert, tells Mental Floss. "There are 15 species of marmot, and groundhogs are one of them," he explains.

Science aside, there are plenty of other visible differences between the two animals. Gophers, for example, have hairless tails, protruding yellow or brownish teeth, and fur-lined cheek pockets for storing food—all traits that make them different from groundhogs. The feet of gophers are often pink, while groundhogs have brown or black feet. And while the tiny gopher tends to weigh around two or so pounds, groundhogs can grow to around 13 pounds.

While both types of rodent eat mostly vegetation, gophers prefer roots and tubers (much to the dismay of gardeners trying to plant new specimens), while groundhogs like vegetation and fruits. This means that the former animals rarely emerge from their burrows, while the latter are more commonly seen out and about.

Groundhogs "have burrows underground they use for safety, and they hibernate in their burrows," Blumstein says. "They're active during the day above ground, eating a variety of plants and running back to their burrows to safety. If it's too hot, they'll go back into their burrow. If the weather gets crappy, they'll go back into their burrow during the day as well."

But that doesn't necessarily mean that gophers are the more reclusive of the two, as groundhogs famously hibernate during the winter. Gophers, on the other hand, remain active—and wreck lawns—year-round.

"What's really interesting is if you go to a place where there's gophers, in the spring, what you'll see are what is called eskers," or winding mounds of soil, Blumstein says [PDF]. "Basically, they dig all winter long through the earth, but then they tunnel through snow, and they leave dirt in these snow tunnels."

If all this rodent talk has you now thinking about woodchucks and other woodland creatures, know that groundhogs have plenty of nicknames, including "whistle-pig" and "woodchuck," while the only nicknames for gophers appear to be bitter monikers coined by Wisconsin Badgers fans.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at

Watch Christmas Island’s Annual Crab Migration on Google Street View

Every year, the 45 million or so red crabs on the remote Australian territory of Christmas Island migrate en masse from their forest burrows down to the ocean to mate, and so the female crabs can release their eggs into the sea to hatch. The migration starts during the fall, and the number of crabs on the beach often peaks in December. This year, you don’t have to be on Christmas Island to witness the spectacular crustacean event, as New Atlas reports. You can see it on Google Street View.

Watching the sheer density of crabs scuttling across roads, boardwalks, and beaches is a rare visual treat. According to the Google blog, this year’s crabtacular finale is forecasted for December 16, and Parks Australia crab expert Alasdair Grigg will be there with the Street View Trekker to capture it. That is likely to be the day when crab populations on the beaches will be at their peak, giving you the best view of the action.

Crabs scuttle across the forest floor while a man with a Google Street View Trekker walks behind them.

Google Street View is already a repository for a number of armchair travel experiences. You can digitally explore remote locations in Antarctica, recreations of ancient cities, and even the International Space Station. You can essentially see the whole world without ever logging off your computer.

Sadly, because Street View isn’t live, you won’t be able to see the migration as it happens. The image collection won’t be available until sometime in early 2018. But it’ll be worth the wait, we promise. For a sneak preview, watch Parks Australia’s video of the 2012 event here.

[h/t New Atlas]


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