Wann Langston, Jr., at UC, Berkeley, supervises the reconstruction of the first skeleton of Dilophosaurus in the early 1950s. TEXAS VERTEBRATE PALEONTOLOGY COLLECTIONS
National Geographic has a post about the "best worst-known" dinosaur - Dilophosaurus. Adam Marsh, a paleontologist at the Petrified Forest National Park in Arizona, led an effort to redescribe Dilophosaurus. That paper was published recently in the Journal of Paleontology.
Now, the new analysis includes two previously unstudied fossil specimens from Arizona, providing the first clear picture of what Dilophosaurus was like in life. Rather than a small dinosaur that relied on gimmicks such as venom and a neck frill to subdue its prey, Dilophosaurus was a powerful predator and one of the largest land animals in North America when it lived during the early Jurassic period, which lasted from about 201 to 174 million years ago.
“It’s a lot bigger than people would think from watching Jurassic Park,” Marsh says.
A Navajo man named Jesse Williams found the first Dilophosaurus specimens in 1940 on Navajo Nation land near Tuba City, Arizona. In 1942, Williams showed the fossils to paleontologists at the University of California, Berkeley, including Samuel Welles, who named it as a new species in 1954.
The team that reconstructed the dinosaur for display used plaster versions of bones to fill in for missing fossils. The resulting dinosaur was “intentionally made to look like [the different predator] Allosaurus … because it was going on a wall mount and they wanted to make it look complete,” Marsh says. The trouble is that the 1954 study, and additional research that Welles published in 1984, didn’t make clear which bones were actual fossils and which were plaster parts.
Subsequent research based on these early papers led to confusion about whether Dilophosaurus was more closely related to turkey-size Triassic carnivores, such as Coelophysis, or larger late Jurassic species, such as Ceratosaurus and Allosaurus.
“It just wasn’t clear after 1984 if they were talking about real anatomy or something described from plaster,” Marsh says. Without anyone spending time and resources on further study, the muddled picture of the animal’s anatomy persisted for decades.
