Parasaurolophus lived in what is now Canada and the United States, in Alberta, Utah and New Mexico. It lived among ceratopsians like Styracosaurus, tyrannosaur relatives including Gorgosaurus and Daspletosaurus, armored ankylosaurs like Euoplocephalus, and other duckbilled dinosaurs like Gryposaurus and Corythosaurus. It lived in a warm climate with wet and dry seasons.
The purpose of Parasaurolophus’s tube-like crest has been the subject of much debate. It was originally thought to function similarly to a snorkel, allowing Parasaurolophus to lead an aquatic lifestyle, but this theory has since been rejected. Another debunked theory is that it could breathe fire, creating a chemical reaction inside the crest.
One of the most accepted theories is that it used its crest like a resonating chamber to create loud calls that could carry over long distances. It could use these calls to alert or communicate with other members of its family or group. It may have also served a function as a visual display.
