Jurassic World and Indominus Rex

Saturday, March 25, 2017

Indominus Rex Attack!

What do you do when you want to boost visitor attendance to your dinosaur-dominated, Jurassic World theme park? Use DNA, from four different dinosaurs, and “in the Hammond lab” create something entirely new and fearsome.

Then … give the new creature a name which signifies its awesome power: Indominus rex. At least … that’s how the story theme works in the 2015 film “Jurassic World.”

So … let’s travel back in time, to the age of the dinosaurs, and meet the four interesting creatures whose DNA led to this new and ferocious predator:

If—contrary to plan—Indominus rex becomes a killing machine, we have to ask: Did she “inherit” that trait from her “ancestors?” Let’s examine the question, starting with Rugops (ROO-gops).

Rugops skull at the National Geographic Museum Spinosaurus Exhibit. Author Ryan Somma

What we know about this theropod, from a physical standpoint, comes from a single, nearly complete and fossilized skull. With its weak but gaping jaw and skull, Rugops—which means “wrinkle face”—is not a predator like the Cretaceous Period Spinosaurus.

Instead, Rugops is a natural-born scavenger, likely waiting in the wings for what’s left of a Spinosaurus-caught, Cretaceous-era fish known as Onchopristis. Living off the scraps of meals, killed by another creature, could be enough for a Rugops.

What does the DNA from Rugops contribute to Indominus rex ? Probably … a massive, gaping jaw. In other words … she isn’t getting the killer streak from Rugops.

How about Carnotaurus  (CAR-no-TOR-us), the “Meat Eating Bull?” 


This Late-Cretaceous theropod, measuring around 25 feet long, likely roamed the plains of South America. At least, that’s where palaeontologist Jose Bonaparte found amazingly in-tact fossilized remains—in Argentina—during 1985. Even its skull and skin impressions were visible once the creature’s skeleton was unearthed.

Those skin impressions have caused palaeontologists to believe that Carnotaurus had bumps across its body. It also had projections on its skull, resembling horns, which led to its “bull” name. It is this physical feature—the two horns—which Carnotaurus “passed-on” to Indomitus rex.

From whom did Indomitus rex inherit her size? Giganotosaurus  (jig-a-NOT-o-SOR-us) can take credit for that.


This “Giant Southern Lizard” lived, in South America, during the Mid-Cretaceous period. Around 40-45 feet long, the Giganotosaurus  weighed around 8 tons and walked—upright—on two powerfully large legs. With its thin and pointed tail providing balance, the creature was likely able to make quick turns while running.

Because of its size, Giganotosaurus likely had no natural predators. Living before T. rex, it probably fed on herbivore dinosaurs. If so, it could have easily sliced through the flesh of its prey.

Because no complete skeleton of this creature has ever been found, paleontologists (and artists) can only speculate about this massive creature (including whether gigantic carnivores and herbivores lived at the same time.)

That leaves Majungasaurus (ma-JUNG-ah-SORE-us), the last of the four DNA-contributing dinosaurs. Once roaming Madagascar, in the late-Cretaceous period, this theropod likely contributed its teeth and lower torso to the lab-developed Indominus rex.

Fearsome teeth

We know about this predator from spectacular fossils located in the Berivotra area of northwest Madagascar. Long before lemurs lived on that island, Majungasaurus grew to around 21 feet in length. It is the best-known of the muscular abelisaurids (which dominated the southern hemisphere just as the tyrannosaurids dominated the northern hemisphere).

Majungasaurus had an unusual body. Its short-but-powerful hind legs were far different from its very small front “legs.” While paleontologists are not sure about the function of those forelimbs, there is little doubt about how a Majungasaurusused its sharp and knife-like teeth!

Plus … scientists believe this dinosaur may also have been … a cannibal. What is the evidence for that?

During 2003, in Madagascar, paleontologists found a fossilized tail bone from a Majungasaurus. That bone contains some interesting marks which paleontologists compared with the denticle spacings of Majungasaurus.

Guess what? They matched … almost exactly!

So … now you know the history of a 43-foot long, 18-foot high hybrid dinosaur called I. rex !

Jurassic World – Indominius Rex