Jurassic puke. (Life News).

As a paleontologist, Peter Doyle spends a lot of time sifting through dirt in search of dinosaur fossils. Most often his efforts turn up, well--dirt. But last fall, the University of Greenwich professor lucked out while fossil hunting in a clay quarry in Peterborough, England. His find? A rock-hard pile of puke. What's so lucky about fossilized vomit? Turns out, it belongs to a 160-million-year-old dolphin-like marine reptile (backboned animal that lays eggs) called an ichthyosaur.

Etched into the vomit are fossilized remains of belemnites, squid-like shellfish preyed on by ichthyosaurs. Unable to digest the bullet-size shells, the sea-dwelling reptiles regurgitated them. The proof? While analyzing the fossil beneath a powerful electron microscope, Doyle discovered acid marks caused by the ichthyosaur's digestive fluids, enzymes (complex proteins) found in its gut that break down food. "We believe this is the first time the existence of fossil vomit on a grand scale has been proven beyond reasonable doubt," he says.

Both ichthyosaurs and belemnites thrived in coastal waters that covered England during the Jurassic period, 205 to 135 million years ago. What will Doyle dig up next? Fossilized snot?