Parasaurolophus was a Long-crested Duck-billed Dinosaur

Parasaurolophus was an Ornithopod dinosaur that lived some 75 million years ago during the Cretaceous period in what is now North America. Parasaurolophus (pronounced pah-Ruhsaw-uh-lofe-Us) was a Hadrosaurid a group known for their bizarre head ornaments. In the case of Parasaurolophus, a large and elaborate cranial crest made it one of the most recognizable Hadrosaurs from the Cretaceous period.

Parasaurolophus is made up of three species; the type species P. walkeri, P. tubicen and P. cyrtocristatus. Parasaurolophus translates to mean “near crested lizard” in reference to Saurolophus which Parasaurolophus was originally thought to be related to.

Quick Facts

What did Parasaurolophus Look Like?

Measuring around 16 feet tall, with a length of around 33 feet and weighing around 3.5 tons, Parasaurolophus was a relatively bulky dinosaur and is often depicted as standing upright on its two thick muscular back legs with a thick pointed tail and oval-shaped body. Parasaurolophus had a long narrow head with large eyes on a mid-length neck, a hard beak and a narrow snout with pebbly textured skin and uniform tubercle-like scales.

Parasaurolophus is most recognizable by its large and elaborate cranial crest that researchers believe could have measured as long as 6 1/2 feet long.

Physical Attributes of Parasaurolophus

Palaeontologists think that Parasaurolophus had good eyesight and good hearing. Being an Ornithopod, Parasaurolophus would have had intermediate intelligence. Additionally, this herbivore didn’t have any weapons since it had no long whipped tail, claws or armor to protect itself with against predators.

The function of Parasaurolophus’ cranial crest has been debated by palaeontologists for centuries with several theories arising about its use – some far more ridiculous than others. It has been said that the crest could have been used to support and move the head, as a weapon in combat amongst individuals of the same species, it could have been used to throw jets of “chemical fire” at enemies similar to the modern day bombardier beetle, as well as being used by an aquatic lifestyle in the form of a snorkel or as an air-trap to keep water out of the lungs.

However all of these theories have been discredited and the overall consensus today is that the crest had several different functions which changed with age. The crest is believed to have been used for visual recognition between species and sexes, for acoustic resonance and for sound amplification (used to create a foghorn-like sound) as well as for thermoregulation.

The cranial crest of Parasaurolophus was hollow and was made up of the premaxilla and nasal bones with long distinct tubes leading from each nostril to the end of the crest and then back into the skull. Scientists believe that the two hollow tubes inside the crest would have been used to make distinctive sounds, distinctive enough to have been identified individually, so that they could call and communicate with others in the herd.

The sound is thought to have been like a fog-horn sounding loud bellow created by exhaling air from the tubes, with females thought to have created sounds at lower-frequencies. Researcher David Weishampel has suggested that an adult Parasaurolophus may have been able to produce frequencies of between 48-240 Hz with juveniles creating higher frequencies of 75-375 Hz that the adult Parasaurolophus were more sensitive too.

What did Parasaurolophus Eat?

This dinosaur was an herbivore and most likely would have eaten pine needles from conifer trees as well as leaves and twigs. Its long neck would have enabled it to reach 13 feet up into the trees for food as well as being able to forage from the ground.

Parasaurolophus had a tough beak which it would have used to snip off vegetation with hundreds of small teeth, arranged in batteries, in its cheeks which it would have used to grind up each mouthful. Because of the narrow beak that Parasaurolophus had it is thought that it was a more selective feeder than other crested broad-beaked Hadrosaurs.

How did Parasaurolophus Move?

It is thought that Parasaurolophus switched between bipedal and quadrupedal movement as it had unusually strong fore legs. The strong back legs of this species would have also made it a relatively fast moving dinosaur having an estimated speed of 25 mph.

It is thought that Parasaurolophus would have been bipedal to walk and run so as to look out for danger as well as to defend itself. When feeding however, Parasaurolophus would have moved to a quadrupedal stance.

Where did Parasaurolophus Live?

Parasaurolophus lived in what is now North America with a span that ranged from Alberta, Canada to New Mexico USA.

65 million years ago in what is now Alberta, Canada the climate would have been warmer without any frosts but with significant wet and dry seasons. Parasaurolophus would have lived in the forest region though would have also migrated to the plains and swamp regions and is thought to have moved to higher ground in order to reproduce and for females to nest.

These dinosaurs would have lived in large herds and when faced with danger they would have moved quickly as these large herds to confuse their predators. One such predator of Parasaurolophus was Albertosaurus.

The Discovery of Parasaurolophus

Parasaurolophus is one of the rarer known Hadrosaurids factually, being known from only a few good specimens.

Parasaurolophus (P. walkeri the holotype) was first described and named in 1922 by William Parks after a skull and partial skeleton (which was missing most of the tail and hind legs below the knees) were discovered in Alberta, Canada. This discovery was made in 1920 by a field party from the University of Toronto. The remains were found along the Red Deer River near Sand Creek in an area now recognized as being the Campanian age, Upper Cretaceous Dinosaur Park Formation

Parasaurolophus was originally thought to be closely related to Saurolophus because of the superficially similar crest which is why it was so named. In later years palaeontologists reassessed Parasaurolophus and realized it was a member of the Lambeosaurine group, a subfamily of Hadrosaurids.

The Importance of Parasaurolophus

Parasaurolophus is an important dinosaur because of its unique crest which has been helping palaeontologists to better understand how these dinosaurs communicated and structured their social groups.

It is hoped that more Parasaurolophus fossils will be found in the future enabling palaeontologists to better understand the differences as well as similarities between the three separate species and  how the species relate to each other.