What was Dilophosaurus really like?
Jurassic Park (1993)
From Scientific American:
Artistic choices aside, scientific understanding of Dilophosaurus was bound to change in the years after Jurassic Park’s release. In the lead-up to the book and film, the field of paleontology was undergoing tremendous change. Advances in computing were revolutionizing the study of fossils, enabling researchers to process enormous data sets in ways unimaginable when Dilophosaurus was first discovered. Take, for instance, cladistic analysis, which identifies discrete, heritable anatomical features that can be compared between animals and that provide a statistical basis for testing hypotheses about the relationships of animals to one another. Researchers can now analyze many more characteristics much more quickly than ever before and thus develop better-supported hypotheses about how dinosaurs are related and how they evolved. Increased computing power and developments in medical and industrial CT scanning also created a nondestructive way to look inside bones and rocks at hidden anatomy.
Not only did the analytical tools available to paleontologists evolve, but in 1998 teams at the University of Texas at Austin began recovering more Dilophosaurus remains in the same region of northern Arizona that yielded the first finds. Every new fossil discovery can support or refute prior thinking about long-vanished organisms. In this case, the new fossils preserved parts of the Dilophosaurus anatomy that were missing or distorted in previously collected specimens.
Fossils are typically collected in large blocks of rock and encased in plaster to protect them during their journey from the field to the laboratory. When they arrive in the museum, paleontologists use dental picks, chisels and miniature handheld jackhammers to carefully remove the rock and expose the fossils. After millions of years of exposure to geologic processes such as crushing and weathering, the fossils we find are most often distorted and incomplete elements. We sometimes disassemble and reconstruct broken fragments to better approximate their original condition, sculpting and adding missing material based on closely related animals.
When Wann Langston, Jr., and his colleagues prepared the first Dilophosaurus skeletons at U.C. Berkeley around 1950, they filled in missing skull parts with casts from the skull of a more complete carnivorous dinosaur from the Jurassic, and they sculpted missing parts of the pelvis out of plaster. No one really knew what those missing parts looked like; the reconstructions represented a hypothesis of the real form of Dilophosaurus—one that could be tested with new fossils.