Question 1

How do you say Mosasaurus?

Accepted Answer

Mosasaurus is pronounced MOH-za-SORE-us. Break it into four parts: MOH, then za, then SORE, then us. The stress falls on the first syllable MOH and the third syllable SORE. Once you say it a few times it becomes very natural, and it is definitely one of the coolest names to drop at school.

Question 2

What does Mosasaurus mean?

Accepted Answer

Mosasaurus means 'Meuse River lizard.' The first part of the name, Mosa, is the Latin name for the Meuse River in the Netherlands, where the very first fossil skull was found in a chalk quarry in 1778. The second part, saurus, comes from the Ancient Greek word for lizard. It is a pretty simple name for one of the most spectacular ocean predators that ever lived.

Question 3

How big was Mosasaurus?

Accepted Answer

Mosasaurus could grow up to about 59 feet long, which is longer than four minivans parked bumper to bumper. It weighed an estimated 30,000 pounds, roughly the same as two full-grown African elephants. It was one of the largest marine predators of the Late Cretaceous period and almost certainly the apex predator wherever it lived.

Question 4

Was Mosasaurus a dinosaur?

Accepted Answer

No, Mosasaurus was not a dinosaur at all. It was a giant marine lizard, most closely related to modern monitor lizards and Komodo dragons. Dinosaurs were a completely separate group of reptiles that lived on land. Mosasaurus lived in the ocean and belonged to the group Squamata, which includes all modern lizards and snakes. The two groups just happened to live at the same time.

Question 5

When did Mosasaurus live?

Accepted Answer

Mosasaurus lived during the Late Cretaceous period, roughly 82 to 66 million years ago. It was one of the last and largest mosasaurs to exist before the mass extinction event at the end of the Cretaceous wiped out the non-bird dinosaurs, pterosaurs, and most large marine reptiles. It shared the planet with famous animals like Tyrannosaurus rex and Triceratops, though their worlds were very different.

Question 6

What did Mosasaurus eat?

Accepted Answer

Mosasaurus was a powerful carnivore that ate large fish, sharks, sea turtles, smaller mosasaurs, and likely anything else it could catch. Scientists have found fossilized stomach contents inside mosasaur skeletons that include fish bones and ammonites, the coiled-shell sea creatures of the Cretaceous. Its double row of teeth, including pterygoid teeth on the roof of its mouth, meant prey had almost no chance of escape once bitten.

Question 7

Is the Mosasaurus in Jurassic World accurate?

Accepted Answer

The Jurassic World version of Mosasaurus is entertaining but exaggerated and inaccurate in several ways. The movie version is shown living in a tank and being fed great white sharks, which is fun but completely fictional. The real Mosasaurus would have been roughly 59 feet long, similar to the movie version, but scientists now believe it had a more streamlined, shark-like body with a crescent-shaped tail fin rather than the eel-like look shown in early reconstructions. Also, Mosasaurus could never have lived in a tank because it almost certainly gave birth to live young in the open ocean and never came to shore.

Question 8

How did Mosasaurus go extinct?

Accepted Answer

Mosasaurus went extinct about 66 million years ago during the same mass extinction event that killed the non-bird dinosaurs. This event was triggered when a massive asteroid roughly six miles wide slammed into what is now the Yucatan Peninsula in Mexico. The impact caused catastrophic climate change, drastically reducing sunlight, collapsing food chains, and wiping out around 75 percent of all species on Earth. Mosasaurus, as a large top predator, would have been especially vulnerable when its prey populations crashed.

Question 9

Where were Mosasaurus fossils found?

Accepted Answer

The very first Mosasaurus fossils were discovered in chalk quarries near Maastricht in the Netherlands in the late 1700s. Since then, fossils have been found in the United States, Russia, the United Kingdom, Sweden, Japan, and Denmark. Many North American specimens come from the Pierre Shale and Niobrara Formation, which were deposited at the bottom of the ancient Western Interior Seaway that once split North America in half.

Question 10

Could Mosasaurus beat a megalodon?

Accepted Answer

This is a fun question but actually impossible in real life because Mosasaurus and Megalodon never lived at the same time. Mosasaurus went extinct about 66 million years ago, while Megalodon lived from about 23 to 3.6 million years ago, meaning there is a gap of over 40 million years between them. In terms of raw size, adult Megalodon may have been slightly larger and heavier, but Mosasaurus was highly intelligent for a reptile and had a very different attack style with its powerful jaws and gripping teeth.

Question 11

Did Mosasaurus have any predators?

Accepted Answer

Adult Mosasaurus at full size almost certainly had no natural predators. It was the apex predator of its ecosystem, sitting at the very top of the food chain in the Western Interior Seaway and other Late Cretaceous seas. However, younger, smaller Mosasaurus individuals may have been vulnerable to large sharks or even larger adult mosasaurs of other species. Scientists have found mosasaur bones with bite marks that appear to have been made by other mosasaurs.

Question 12

How did Mosasaurus swim?

Accepted Answer

Scientists believe Mosasaurus swam primarily by sweeping its large, crescent-shaped tail fin from side to side, similar to how a shark swims today. Its four flippers were used for steering and stability rather than propulsion. This swimming style would have made it fast and agile in open water. Earlier reconstructions showed it wiggling its entire body like an eel, but fossil evidence of tail shape and soft tissue impressions from related mosasaurs have updated this picture significantly.

Question 13

Who discovered Mosasaurus?

Accepted Answer

The first notable skull was discovered in 1778 by miners working in chalk quarries beneath the city of Maastricht in the Netherlands. The fossil became famous across Europe and was famously seized by Napoleon's army in 1795. In 1808, French naturalist Georges Cuvier identified it as a giant marine lizard and used it as evidence for the concept of extinction. The official scientific name Mosasaurus was given by British naturalist William Daniel Conybeare in 1822.

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