While it looked normal from the neck down, it looked almost as if it had a
trombone on its head!
Its name, which means "like Saurolophus," refers to the resemblance of the
crests of these two duckbilled dinosaurs. However, the crest of Saurolophus
was solid bone and the crest of Parasaurolophus was hollow. The hollow space
within the crest of Parasaurolophus reached the nostrils and looped down to connect to the
back of the throat.
The elongated, crested skull of the male Parasaurolophus has
been the topic of debate among paleontologists for years. At first,
paleontologists thought this crest was used underwater, perhaps as a snorkel or a place to
store extra air. Other suggestions included extra space to increase the
animal's sense of smell or an area used to cool its brain. The function of the
crest is now thought to relate to hadrosaur social behavior. Because of their size and
shape, crests could have been for display. They may have helped other members of its
species identify the animal, and the crest may have shown how old the animal was and its
sex.
Also, because the crest was hollow and connected to the lungs, it would have made a
resonating chamber. Sounds would have been made by a vocal organ or voice box and
"pushed" through the crest, making a deep honking call. In this way,
the animal could have communicated and warn others of impending danger.
The females had shorter crests and may have made higher noises.
The difference in sounds may have aided in attracting a mate.
Each crest was unique and would, most likely, have made a unique sound. The
uniqueness of each Parasaurolophus would have made it easier to return to mates, and for
babies to find their parents. All lambeosaurines would have used their
"voices" to announce themselves, to warn their hatchlings, and to challenge
other animals that invaded their territory.
Click here to hear what they might have sounded like!