The Spitting Jurassic Park Lizard: Was It Real?

One of the most memorable and terrifying moments in the 1993 film Jurassic Park involves a creature that was, until then, relatively obscure to the public. In a dark, rain-swept scene, a seemingly small and inquisitive dinosaur with chirping sounds suddenly transforms into a formidable predator. It unfurls a vibrant, rattling neck frill and spits a blinding substance, creating a lasting image of prehistoric horror. The scene’s effectiveness left many viewers wondering about the reality behind this unique creature.

The On-Screen Depiction in Jurassic Park

The dinosaur that confronts the stranded computer programmer Dennis Nedry is identified as a Dilophosaurus. In the film, it is portrayed as smaller than a person, seeming deceptively harmless at first. Its most striking features are cinematic inventions: a large, expandable neck frill that flares out as a threat display and the ability to spit a thick, dark venom to disable its prey.

The movie’s Dilophosaurus is presented with vibrant coloration, particularly in its neck frill, which adds to the visual shock of its attack. This design choice was intended to make the creature more visually distinctive from other theropods in the film. The filmmakers deliberately scaled down the animal and equipped it with these biological weapons to craft a specific horror for Nedry’s demise, ensuring its brief appearance would be unforgettable.

Scientific Profile of Dilophosaurus

The actual Dilophosaurus wetherilli was a significantly more imposing animal than its on-screen counterpart. Living during the Early Jurassic period, about 183 million years ago, it was the largest known land predator in North America of its time. Fossil evidence indicates that Dilophosaurus was a bipedal carnivore that could reach lengths of up to 23 feet (7 meters) and weigh around 880 pounds (400 kilograms), comparable in size to a brown bear. Its name, meaning “two-crested lizard,” refers to its defining feature: a pair of thin, arched bony crests on its skull.

These crests were likely used for display, perhaps to attract mates or identify members of its own species, and may have been covered in keratin, making them appear larger in life. There is no fossil evidence to support the existence of a neck frill or any specialized anatomy for spitting venom. The jaw, once thought to be weak, is now understood to have been equipped with powerful muscles, suggesting Dilophosaurus was a formidable predator.

Cinematic Choices and Their Inspirations

The filmmakers’ decision to alter the Dilophosaurus was an example of artistic license, prioritizing dramatic effect over scientific accuracy. The creative team borrowed traits from modern animals to achieve a visually distinct creature for a key scene. The expandable neck frill was directly inspired by the frill-necked lizard (Chlamydosaurus kingii), an Australian reptile that uses its frill to intimidate potential threats.

The venom-spitting ability was likely inspired by animals like the spitting cobra. In the original novel by Michael Crichton, this ability was justified by the idea that such a feature, involving only soft tissues, would not fossilize. By combining these real-world biological concepts with the dinosaur’s existing crests, the filmmakers created a hybrid creature perfectly suited for its cinematic role. These choices ultimately shaped the public’s perception of Dilophosaurus for decades.