Research reviewed 30 July 2026. Scientific interpretations may change as new evidence is published.
Parasaurolophus was a large plant eating dinosaur with a long, hollow crest that extended from the back of its skull. The crest probably helped it communicate and recognise others, but nobody can know the exact sound that this dinosaur made.
| Fact | Evidence based answer |
|---|---|
| Scientific name | Parasaurolophus walkeri |
| Time period | Late Cretaceous, about 77 to 73 million years ago |
| Fossil locations | Canada and the United States |
| Diet | Herbivore |
| Estimated length | About 9 metres |
| Estimated mass | Roughly 2.5 to 5 tonnes |
| Famous feature | A long, hollow tube shaped head crest |
Parasaurolophus was a hadrosaurid, often called a duck billed dinosaur. These plant eaters had broad beaks and batteries of closely packed teeth. It belonged to the hollow crested branch called lambeosaurines.
The best known species is Parasaurolophus walkeri from Alberta. P. tubicen and P. cyrtocristatus are known from the south western United States. Their crests differ in shape.
Its name means "near crested lizard", after a comparison with Saurolophus. Much of our knowledge comes from a limited number of partial skeletons.
Parasaurolophus lived about 77 to 73 million years ago. Fossils are known from Alberta, New Mexico and Utah, then part of a western landmass beside a shallow inland sea.
Its habitats included river plains, wetlands and forests with conifers, ferns and flowering plants. Other residents included horned and armoured dinosaurs, hadrosaurids and large theropods.
Rock layers help researchers establish where and when each species lived.
Parasaurolophus had strong hind legs, shorter front limbs and a stiffened tail. It probably fed on four legs and rose onto two for faster movement.
Central front fingers formed a weight bearing pad. Tendons stiffened its raised tail and helped balance the body.
Nasal passages looped through the crest and back into the skull. Computer models suggest that moving air could produce deep sounds. A young specimen had a low, rounded crest that lengthened with age.
Parasaurolophus was a herbivore. Its broad beak could crop vegetation, while hundreds of replacement teeth formed grinding surfaces farther back in the mouth. As teeth wore down, new teeth moved into place.
It probably ate a mixture of leaves, twigs and other available plant material. Its ability to move on two or four legs may have allowed it to feed at several heights. Scientists cannot identify every plant it ate, so museum scenes showing one precise favourite food should be treated as illustrations rather than proof.
The first named Parasaurolophus walkeri includes a skull and much of the body. Further skulls revealed more than one crest shape.
CT scans reveal internal passages without damaging fossils. Digital models test how air might resonate inside the crest. They suggest possible sounds, not the animal’s exact voice.
A young specimen nicknamed Joe preserved a small crest and many body details. Its growth shows how the adult crest developed and helps researchers recognise juveniles.
The crest could have served several roles. Hollow passages support sound production, while its shape may have signalled species or age. The importance of each role remains debated.
Models depend on assumptions about missing soft tissues and airflow. They can suggest a low tone, but cannot recover the exact call.
Researchers also ask whether crest differences reflect species, age or sex. More complete fossils are needed.
The crest was not a snorkel. Its closed tip could not take in air underwater.
It did not chew like a modern cow. Its jaw movement and digestion were different.
Computer simulations offer possible calls, not Cretaceous recordings.
The crest probably helped with sound, display and recognition. It may have served several functions at the same time.
Air passing through its long internal tubes could have resonated. Models suggest a low sound, but the exact call is unknown.
No. The crest had no open breathing hole at its far end, so the snorkel idea does not fit its anatomy.
Adults were about 9 metres long. Mass estimates vary, but roughly 2.5 to 5 tonnes is a useful range.
It ate plants and could crop vegetation with its beak before processing it with batteries of teeth.
It could probably use both. Four legs suited steady feeding, while two legs may have been useful for faster movement.
No. Juveniles had much smaller, rounder crests that lengthened and changed shape as they grew.
Its fossils have been found in western North America, including Canada and the United States.
