These fossils of dinosaur tracks near Tuba City , Arizona are thought to be from Dilophosaurus. In the movie Jurassic Park, Dilophosaurus was the small dinosaur that had a frill on its neck and spat poison. Actually they grew up to 20 feet tall, and we have no evidence of either frills or poison. For size reference, the black object is my cell phone. Still, this dinosaur fit better into the movie than most of the others featured. Why?