The “near crested reptile” was found in Western North America and described by William Parks in 1922. Parasaurolophus lived in the Late Cretaceous Period about 80 to 73 million years ago. It was 7.6 meters (25ft) in length, 4 meters (13ft) in height and weighed 4 tons.
Parasaurolophus can be found on both Isla Nublar & Isla Sorna gathered in herds that are usually found around large sauropods. Laura Sorkin also had a male herd of Parasaurolophus on Nublar as part of her private stock in her isolated section of the island. Parasaurolophus are known to be hunted for food by Tyrannosaurus rex, as seen in The Lost World and Jurassic Park ///.
The only way to identify the Parasaurolophus is a question of color. Females vary in color with blue or black horizontal, possibly lateral stripes, base color of green and maybe a yellow, white, brown, or grey underbelly. Males are often brown & show a hint of red. While it is said that the female Parasaurolophus on Jurassic Park have a slight curvature to their skulls, the skull is generally exactly the same as the males after closer investigation and this makes the sexes of the species indistinguishable from another save for the separate colors. It is also worthy of notation that the Parasaurolophus possibly may have an individual ranking system where dominant animals happen to feature different vibrancy of red on their crests & neck. This can in fact be seen in both encounters with both males and females featuring red crests/necks and also members of the same sex not featuring this color on their head and neck as dominant by looking blander in color this could even be the result of the individualism of the animals, lighting used on film or CGI rendering of the animals. The coloration of the animal is affected by the light sources present in their environment as well that could be causing this kind of appearance or discrepancy in appearances, rather.
The Parasaurolophus herd in Isla Sorna in 2001 also seem to feature this type of red in varying shades as well on their necks and around their crests as noted also, but this looks more deliberate to be different and could even indicate individualism as intended. Herding between the species seems to have both male & females divided from one another possibly based on The Making of The Lost World (p.25)
“‘We had to design new paint schemes not only for the new dinosaurs, but for some of the already-designed dinosaurs from the last movie,’ Winston explained, ‘because now there were male dinosaurs, as well as females; and typically in nature the males of any species are far more brightly colored. We also wanted to make sure that the audience would be able to tell the males and females apart. It was a great of fun to run the gamut of color and come up with interesting designs. The colors on the females for the first film had been fairly subdued; but with male animals, there were may more possible colorations.’”
If the herds are gender divided, some have postulated that the Parasaurolophus females are territorial, and the source from this comes from an informational video at Isla Adventura and thus is suspect, other theories have been suggested of versioning (as mentioned earlier), and some have suggested that the Parasaurolophus are possibly of differing species though there is no evidence for any other species but P. walkeri in the S/F continuity family. There is a concept art piece featuring a design of the female Parasaurolophus that has some similarity to what we see in the films as well, but there are still major differences between the concept art piece and what we see on film.
Parasaurolophus were one of the dinosaur attractions housed in the Jurassic World theme park on Isla Nublar. They were housed in the Gallimimus Valley, Gyrosphere, Petting Zoo, and Cretaceous Cruise attractions where they mixed with other herbivorous dinosaurs. Most notably, two Parasaurolophus can were seen during Zach and Gray Mitchell‘s tour of the Gyrosphere valley, engaging in a dominance fight in the background. Both of which held similar coloration patterns to the males seen on Sorna.