Jurassic Park: 15 Things You Never Knew About The T-Rex

In 1993, the world was introduced to the onscreen version of Michael Crichton’s best-selling novel, Jurassic Park. Directed by Steven Spielberg, audiences were taken to a world where prehistoric amusement parks were a possibility. The thrilling action-adventure movie became one of the most popular films of that year and still stands as a crowning achievement for Spielberg.

Though the franchise has continued throughout the years including the most recent installment Jurassic World, one character remains as a fan favorite: the mighty Tyrannosaurs Rex.

Introduced in the first movie as a “villain” of the film, the T-Rex had made appearances (in one form or another) throughout the series. Though the dinosaurs of the movie only appear in 14 minutes of the original film, the T-Rex became the focal point whenever she was onscreen. Between CGI technology and fully functional scale models, the predator was brought to life to frighten audiences throughout the world.

In this article, we plan to take a behind the scenes look at the creation of the “star” of Jurassic Park and some of the little-known facts about its history.

From its iconic onscreen moments to lasting movie legacy, here are the 15 Things You Never Knew About the T-Rex.

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After being selected as Jurassic Park author Michael Crichton’s first choice for directors, Steven Spielberg began assembling a team to bring his modern prehistoric tale to life. Though responsible for some of the most imaginative movies of our generation, Spielberg still needed additional assistance with creating both CGI and animatronic dinosaurs.

His team of dinosaur creators tapped talented professionals that became known for their work on popular sci-fi franchises including Star Wars, The Terminator, and Alien.

Spielberg hired Stan Winston on the basis of his work creating the alien queen in Aliens. Winston built the life-size lizards, including the Tyrannosaurus rex and triceratops. Spielberg hired stop-motion puppeteer Phil Tippett (worked on Star Wars) to animate model dinosaurs that would be superimposed in post-production, and Dennis Muren (fresh from creating the molten-metal morphing effects in Terminator 2: Judgment Day) to see if dinosaurs could be created using computer-generated imagery.”

14 Two versions of the T-Rex were created

Jurassic Park T-Rex Full Body and Head

The creation of the T-Rex was a daunting task, to say the least. The crew immediately began work on creating a full-scale model that could be used to incite immediate fear when standing next to humans. The final model used in the movie was an enormous beast that stood 18 feet tall and was 36 feet long. However, issues arose when trying to control the large mechanical dinosaur in more intimate shots.

With a focus more on his overall movement than this massive head, the crew later constructed a head-only model that could be safely used for those intimate, scary moments that the storyboard called for. Using the same materials as the full-scale model, the final model has the ability to create more expressive, intricate movements to add to the close-ups.

13 T-Rex model was incredibly dangerous

Jurassic Park T-Rex Attacking Jeep

Jurassic Park took on the improbable task of recreating several species of dinosaurs that had not roamed the Earth in 200+ million years. While many were created using special effects, the T-Rex (being the star of the movie) had to be created as close to scale as possible. However, with the completion of his full body model, the final product turned out to be a huge safety concern. With a final weight of around 12,000 lbs., the T-Rex had the potential to cause significant damage.

The crew had to implement certain safety precautions just for its operation. These procedures included “us[ing] flashing lights to announce when it was about to come on, to alert the crew, because if you stood next to it, and the head went by at speed, it felt like a bus going by.”

Wow! Imagine being taken to the hospital and having to report you got hit by a speeding T-Rex.

12 Sound Effects Included Animal And Tree Sounds

Jurassic Park T-Rex Footstep

Not only was the task of recreating prehistoric animals a challenge but producing their sounds as well. Of course, no one had any idea what the T-Rex’s roar sounded like so the process of creating one required the use of the entire animal kingdom.

According to an article in Scientific America,” …The T. rex roar from the film was a combination of a baby elephant’s squeal, an alligator’s gurgling, and a tiger’s snarl. Its breath was the sound of air escaping a whale’s blowhole.”

As for the unforgettable sound of its footsteps, Spielberg and his crew tapped the natural sounds found in nature. This sound effect was created from massive sequoias crashing into the ground. Although these may seem like very usual combinations, nothing was stranger than some of the other dinosaurs’ roars being comprised of animals having sex. Childhood ruined.

11 Spielberg Would Scream Through A Megaphone for its Growls

Steven Spielberg Jurassic Park Set

In the process of filming, Spielberg did his best to create some degree of tension throughout the movie. With a movie filled with intense chase scenes and fear-inducing situations, he did his best to create such situations on set for the actors to react to. Well, for the most part.

Since the creation of the T-Rex’s spine-curdling growl had to be produced in post-production, Spielberg utilized other methods to generate appropriate sound effects for the best reactions. While filming scenes for the T-Rex and the other dinosaur species seen throughout the movie, he would act as their stand in by screaming through a megaphone.

Although he intended to help the actors get into character, his makeshift dinosaur screaming just led to fits of laughter from both the cast and crew.

10 The T-Rex Model Would Come Alive on its Own

Jurassic Park T-Rex Pushing Jeep

Can you imagine how terrifying it would be to be chased by a T-Rex? Anytime the T-Rex appeared onscreen, its ginormous presence and hair-raising roar would frighten audiences. Although it was meant to incite fear in the hearts of fans, it also managed to scare the crap out of the crew too.

The T-Rex was known to occasionally malfunction when it came into contact with water. Producer Kathleen Kennedy recalled, "The T. rex went into the heebie-jeebies sometimes. Scared the crap out of us. We'd be, like, eating lunch, and all of a sudden a T-rex would come alive. At first, we didn't know what was happening, and then we realized it was the rain. You'd hear people start screaming." We can only imagine how terrifying that must have been.

9 The water ripple scene was created with guitar strings

Jurassic Park Water Ripple Scene

One of the most iconic moments of Jurassic Park seems very simple. The first appearance of the T-Rex began with just footsteps in the background that caused ripples in two glasses of water.

Simplistic in its appearance, this scene became the perfect setup for the approaching enemy. Incidentally, music was Spielberg’s motivation for the scene. According to Business Insider, “Spielberg was inspired to do this shot after listening to an Earth, Wind, and Fire song in his car, which caused the mirror to shake.”

However, the attempts to pull off such a simple effect proved very challenging for Spielberg and his crew. The ripples would not form correctly or the shot so alternate methods had to be used to create just the right effect.

In an interview included on the Jurassic Park DVD, Special Dinosaur Effects Supervisor Michael Lantieri shared that, "Finally, messing around, with a guitar one night, I set a glass, I started playing notes on a guitar and got to a right frequency, a right note, and it did exactly what I wanted it to do.” They duplicated this method onset with a crew member plucking a guitar string that had been attached through the Jeep.

8 The T. Rex Coming Through the Window Was an Accident

Jurassic Park Kids in Jeep Scene

Some of the most memorable moments in cinematic history have taken months of careful planning and detailed storyboarding. However, on those rare occasions, movie magic happened from an unplanned reaction or take that captures the perfect moment on film.

In the case of Jurassic Park, those unforgettable moments had to tap into some very terrifying circumstances. For the Jeep scene in the movie, young characters Lexi and Tim are trapped under the glass of the sunroof. Though the scene itself was planned out in detailed, no one accounted for the strength the of the glass against the force of the T-Rex head. As a result, the glass cracked and shattered by accident, causing the children’s screams to increase.

Although the glass breaking was unplanned (thankfully, no one got hurt), its serendipitous addition intensified the tension and fear of this unforgettable scene.

7 Spielberg wanted the T-Rex to be the “heroine” of the movie

Jurassic Park T-Rex Final Scenes

Fans of Jurassic Park may be surprised to know that the movie was planned with a very different ending. According to IMDB, “In the original script, the T-Rex skeleton in the lobby was hooked up to pulleys like a giant marionette. In the ending, Grant was going to man the controls and act as puppeteer, using the skeleton's head and feet to crush the raptors.”

However, no seemed to like that ending and found it to be too fake. So, at the last minute, Spielberg came up with the idea of making the T-Rex the “hero” of the movie and created the ending that was used in the final cut. Considering all the hell that she put the characters through, it was nice to see her save their lives in the end.

6 The T-Rex had to be blow dried

Jurassic Park BTS T-Rex Skin

No one can forget the first time they saw the T-Rex onscreen in Jurassic Park. From its massive head to its humungous footprint in the mud, its appearance shook audiences to their core. All the while, the movie’s most remarkable scene took place in the pouring rain, a factor that was considered the mechanical T-Rex’s kryptonite.

According to an interview with The Atlantic, puppeteer John Rosengrant shared “We found out not long before we were going to shoot that it was going to be raining [in the scene]. So it went from this beautifully tuned machine that worked fantastically to… suddenly the foam-rubber skin started absorbing water, and now all of the calculations were off and it started to shudder."

Due to the thick foam latex skin covering its entire body, the full-scale model was prone to, well, shrinkage. Water would not only affect its mechanical operation but its outward appearance as well. To prevent any further repairs and patchwork on his skin, the crew had to attack the pooling rain with many hair dryers and towels.

5 The Jeep Chase Was Hard To Shoot and Historically Inaccurate

Jurassic Park Jeep Chase Scene

The climactic Jeep chase scene ended up being one of the most difficult scenes for the effects crew to create. Since no data existed of an actual T-Rex running, animators had to rely on trial-and-error for the process.

Although they finally got his chase scene down, there was a mistake made in the final cut. As the heroes of the movie tried to escape the clutches of the T-Rex, they were chased down by the massive monster. While the speedometer showed the Jeep hitting upwards of 40 mph, this was actually a mistake by the filmmakers.

Based on the data paleontologists have about the Tyrannosaurus Rex, they have concluded that this species of dinosaur may have been able to get to 25 mph at the most.

4 T-Rex's paper stand-in on set

Jurassic Park BTS Fake T-Rex Head

The special effects work on Jurassic Park utilized technology that was years ahead its time. Not only did the CGI technology help capture the best interpretation of dinosaurs roaming the Earth but it left a lasting impression on other filmmakers.

However, to achieve such revolutionary feats, the post-production work took some considerable time. On set, the actors were left to use their imagination to visualize their prehistoric foes… and paper cutouts.

According to behind the scenes footage from the movie, the gigantic dinosaurs were replaced with homemade art project versions. Serving as a stand-in for the CGI-created enemy, the crew would use paper cutouts for the T-Rex attacked to wooden sticks.

Much like the effectiveness of Spielberg’s megaphone screams, the paper dinosaurs served as an excellent source of amusement for everyone on set.

3 Movie Mistake: The T-Rex Was Missing A Tooth

Jurassic Park T-Rex Missing Tooth

Poor T-Rex. Between being subjected to gallons of rainwater to being regularly patched up for shrinking skin, this mechanical enemy really had a rough experience onset.

It was only a matter of time before the T-Rex began to fall apart over time. One such instance actually made it into the film. During the infamous Jeep scene with the two young characters, the T-Rex head was used to fight with the kids. While pushing down on the Plexiglass, not only did the T-Rex break the glass but it also lost a tooth, getting stuck in the metal of the car.

If you pause your DVD in just the right shot, you can see the missing tooth the crew failed to repair.

2 Director's Trademark Used in T-Rex Chase Scene

Jurassic Park Mirror Shot

Fans of Steven Spielberg have to come to learn the unique touches he places in all of his films. Spielberg has a way of capturing human emotion onscreen like no other director.

From his iconic family films to his heart-stopping action movies, audiences always experience the memorizing storytelling that only Spielberg can provide. He also has a tendency to incorporate special hints and touches into his films. These special Easter Eggs have become fun treasure hunts for fans and have appeared in each of his films.

While the “Spielberg Face” (a close-up show of the main character(s) looking shocked, frightened, or perplexed) can be found in Jurassic Park, he also managed to added another Easter egg just for the T-Rex.

Spielberg's also known for incorporating jokes into signs or directions, and the chase scene made hilarious use of the rearview mirror during a particularly intense moment. An image of the T-Rex with its jaws wide open can be seen about the mirror’s message “Objects in mirror are closer than they appear."

1 The Legacy of The T-Rex's Roar and Its Lasting Impacts

Jurassic Park T-Rex Roar

The legacy of Jurassic Park extended far beyond the simple take of a prehistoric themed amusement park (something we hope never becomes a reality). The technology used for the movie itself served as inspiration for many filmmakers and production companies.

The work of Stan Winston particularly stood out as some of the most revolutionary sound work of its time. His incorporation of various animal sounds for the iconic T-Rex roar set a new standard for giant monster movies. Not only have his techniques been duplicated on other films but the T-Rex roar itself has been used for other larger-than-life beasts.

Jurassic Park and its “star” the T-Rex has become a mainstay in pop culture since its release and will remain significant for years to come.


Have any other trivia to share about Jurassic Park's T-Rex? Share it in the comments!

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