Parasaurolophus is a dinosaur from the Upper ............ of what is now North America, about 76.5–73 million years ago. It was a herbivore that walked on both two and four feet. It probably lived in ............. Parasaurolophus was a ............. They had a large head ............, which was a long curved tube. It went upwards and back from the skull. The crest has been much discussed by scientists. They think that the Parasaurolophus might have used it to ............. Cretaceous herds hadrosaur crest communicate