Gravelly guts (Image: Laura Codorniu/Luis M. Chappe/and Fabricio D. Cid)

IF YOU’RE flying, it’s normally best to travel light, but one prehistoric flying reptile didn’t get the memo. It took to the skies with a cargo of gravel in its guts.

The gravel-muncher in question is Pterodaustro guinazui, and it lived towards the end of the dinosaur era. While examining a new fossil of the species, Luis Chiappe of the Natural History Museum of Los Angeles County and colleagues discovered that its abdomen contained 29 stones (see photo), ranging from 1.5 to 8.4 millimetres across (Journal of Vertebrate Paleontology, DOI: 10.1080/039.033.0508).

P. guinazui is known as the reptilian version of the flamingo because its unusually long skull gave it a beak-like snout. It is also thought to have used its hundreds of long, thin teeth to filter morsels out of shallow water.


Chiappe says the pterosaurs may have used the stones to help grind up the tiny crustaceans it ate. Again, this strategy is commonly seen in filter-feeding birds like flamingos.

“This is a really special pterosaur,” says Lorna Steel of the Natural History Museum in London. Most species ate fish or insects, using sharp teeth to rip them apart, and would not have needed stomach stones. “This is probably unique to the filter-feeding pterosaurs.”

This article appeared in print under the headline “Prehistoric flier had gravelly guts”