These Dinosaurs Tooted Their Own Horns

Thursday, November 1, 2018

An illustration of two Parasaurolophus dinosaurs bellowing at each other to claim territory.  Corey Ford/Getty Images

The sounds made by duck-billed dinosaurs are less of a mystery now.

Duck-billed dinosaurs may have “tooted” different notes from their trumpet-like nasal passages depending on what species they were, new research suggests.

Paleontologists made this discovery while studying an unnamed species of the duck-billed Parasaurolophus. This type of dinosaur had nasal passages connected to a hollow crest that stretched over the back of its head.

They discovered that this type of Parasaurolophus would’ve been able to produce a sound with a different pitch than two other species of Parasaurolophus. Specifically, it would’ve produced a lower pitch than the P. cyrtocristatus and a higher pitch than the P. walkeri.

This suggests that different species of duck-billed dinosaurs marched to the beat of their own drum, so to speak, by tooting different notes on their horns.

Paleontologists are still investigating whether the unnamed Parasaurolophus is a previously unknown species or a known species at a different life cycle or sex than we’ve seen before. They presented this unpublished research at the 78th annual Society of Vertebrate Paleontology meeting in Albuquerque, New Mexico, in October 2018, according to Live Science.

One of the reasons these findings are so significant is that we don’t know what sounds dinosaurs made with their vocal cords. That’s because it’s hard to find fossilized versions of these cords, which are soft tissue.

In contrast, the Parasaurolophus’ naval cavities and hollow crests are much more easily preserved. These don’t give us all the clues, but they do give us a peek into what dinosaurs may have sounded like.

“We can never be exactly certain what sounds these dinosaurs actually made,” Caroline Rinaldi, an associate professor of anatomy at the University of Texas Southwestern Medical Center, told Live Science (Rinaldi isn’t involved with the new research). “But the authors used an innovative combination of physics and physiological principles to develop a hypothesis that different species of Parasaurolophus (with different crest shapes), produced sounds of different frequencies.”