A Prehistoric Trumpet by the Water

About this drawing

The star of any parasaurolophus reflection is that long crest sweeping back from the head, a feature that has puzzled scientists for a century. It wasn't solid. Inside, hollow tubes ran from the nose up to the tip and back down again, a lot like the slide on a trombone.

Early ideas were all over the place. Some thought it worked as a snorkel, others as an air tank or a way to push through branches. None of them held up. Fossils showed there was no opening at the end of the crest, so the snorkel idea was out.

In the 1990s, researchers at a New Mexico lab scanned a beautifully preserved skull and built a computer model of those inner tubes. Then they simulated what would happen when air moved through them. What came out was a low, deep sound, something like a foghorn or a French horn, that could carry a long way.

That points to dinosaurs calling to each other across the landscape, perhaps to warn of danger or attract a mate. The crest also varied by age and species, so it may have helped them recognize each other on sight. Picture a herd bellowing across a marsh, and you get a concert nobody has heard in 75 million years.

• dinosaurs
• parasaurolophus
• reflections
• adult coloring