The Dilophosaurus is probably the best-known dinosaur whose fossil remains have been found in Arizona. That’s because the 1994 blockbuster movie “Jurassic Park” made Dilophosaurus famous—or at least an imaginative version of it.
In the movie, it is portrayed as a small, bipedal predator with a flaring frill and venomous spit, along with a mouthful of sharp teeth. The real Dilophosaurus, though, was far larger than the movie version, at least 8 feet tall, with a length of over 20 feet. This was a fearsome animal- possibly the largest land animal of the early Jurassic period and likely the dominant predator of its time.
There is no fossil evidence of the frill or the venomous spit, but it did feature two prominent crests atop its skull, hence the genus name, which means “two-crested lizard”. Those crests are believed to be too delicate for anything but visual display purposes, for attracting mates or other communication.
The best Dilophosaurus fossils have been found on the Navajo Nation, in Kayenta Formation sandstones east of Cameron, Arizona. The Navajo Nation has worked with museums to care for these precious fossils and ensure that they are carefully studied. And, the Museum of Northern Arizona in Flagstaff displays a beautiful restoration of a Dilophosaurus skeleton.
Thanks to the excellent quality of the fossils and the thorough study of them, Dilophosaurus may be the best-understood dinosaur from the early Jurassic.
This Earth Note was written by Steve Schwartz and produced by KNAU and the Sustainable Communities Program at Northern Arizona University.
