Stones & Bones: Jurassic Barf
by Mark Rose
Ever see your cat throw up a fur ball? Lots of animals upchuck things they can't digest or that might injure their intestines. Owls and hawks spit up feathers, fur, and bones of their prey. Sperm whales vomit the hard beaks of the squids they eat. Dinosaurs were no different. Recently, some dino vomit was found at Las Hoyas in central Spain. Dated to the Cretaceous period, about 115 million years ago, the vomit consisted of fossil bones and feather impressions from four birds. Spanish paleontologists say the bones aren't crunched up as in coprolites (fossil poop), but show some pitting from stomach acids. It appears that the birds were eaten, then their bones and feathers were thrown up.
British scientists have now pushed back the date on prehistoric barf to the Jurassic period, 160 million years ago. The evidence? A mass of pointy internal shells from squid-like belemnites (small fossils) that were found in a quarry north of London. How do they know it's vomit? When they looked at it under high magnification, they could see the shells had been etched by acid, suggesting they had been exposed to digestive juices. Further, most of the shells are from young animals, so they didn't die off naturally. They believe the shells were thrown up by an ichthyosaur, a marine reptile that looked a bit like a dolphin and reached up to 45 feet in length. The belemnite shells would have damaged the soft tissue of the animal's gut, so puking was the only way to get rid of them.
- How did these paleontologists know that what they were studying was vomit?
[anno: They were able to see etchings from stomach acid on the shell surfaces.]
- Why do you think it is important for scientists to study dinosaurs?
[anno: Answers may vary but could include that it is important to know about where the species have come from because it helps us learn more about today's organisms and about the history of the Earth.]