Exhibit Spotlight: Dilophosaurus wetherilli

Exhibit Spotlight: Dilophosaurus wetherilli Another dinosaur catapulted to popular fame by Hollywood, its real-life persona also differs the most from its stint in Jurassic Park. It’s an eye-catching dinosaur, and it has one of the most striking positions in the park, so questions about it come up surprisingly frequently.

Image Credit: Teratophoneus , via teratophoneus.deviantart.com

  • Dilophosaurus had wanderlust: its footprints, sometimes called Eubrontes, have been found from St.George to Dinosaur State Park, Connecticut. They are the most common fossil evidence for this type of dinosaur. Though we can’t know for sure that Dilophosaurus made the Eubrontes tracks, their size and shape matches well enough that scientists often attribute them to this species.
  • Even with all these footprints, scientists have described only 5 skeletons of Dilophosaurus so far, all of which come from Arizona. Though Dilophosaurus was one of the largest carnivores of its day, it still had a light build and delicate bones. This makes preservation of the animal’s skeleton unlikely in most places, but conditions in Arizona seem to have worked out fine, fortunately for us.
  • Some workers report that the Eubrontes traces found in Connecticut show possible evidence of feathers, at least on parts of this animal. The traces come from prints left in the mud after the animal sat down. If those marks really represent feathers, they rank among the oldest evidence of feathers known to science. However, such reports have not ruled out other possibilities, like the marks might be cracks in the mud. Further study or new discoveries may clarify this situation in the future.
  • Other traces of Eubrontes found in St. George show that Dilophosaurus used its forelimbs to pull itself to its feet.
  • It did not spit poison. That legend sprang from an analysis that determined Dilophosaurus had weak jaws. One of the scientists involved with the study speculated that venom may have played a role in the animal’s lifestyle, but no one ever confirmed it—to the contrary, evidence suggests that it didn’t have enough extra room in its skull for venom sacs. Its jaw strength remains a case for debate, but even if its jaws lacked relative strength, other characters suggest it may not have needed it: it may have eaten mostly fish. A sushi-eating Dilophosaurus certainly would explain all those footprints near ancient lakes and riverbanks.
  • That frill that rattled like a snake in Jurassic Park was SO not a part of the real animal, either. Think about it: if a Dilophosaurus wanted to attack you, why would it want to make you run away, fight back, or risk making you do something else that makes you harder to eat or hit? The frill and venom both only makes sense from a storytelling or moviemaking perspective, not from any kind of practical design standpoint.
  • The thin crests on the animals’ head likely served a display function of some sort; they were too thin for anything rougher than showing off. In life they may have been brightly colored to attract attention, mates, or for scaring off other animals. They might have served an even more novel function, like cutting down on glare coming from the surface of the water to make fish easier to see, like the brim of a hat. Since these structures seem strongly connected to a behavior that leaves no fossils, we may never know for sure.

—Jeff Bond