Spread along the southwestern coast of Peru, the 9.9 to 8.9 million year old rock of the Pisco Formation has yielded some stunning fossils. Paleontologists working there have found the bones of enormous predatory whales, delicately-preserved shark jaws, and sea turtles, just to name a few highlights. But even those finds pale in comparison to a real rarity that was announced just last month: prehistoric whale vomit.

The unusual fossil, described by paleontologist Olivier Lambert and colleagues, is encased in a chunk of exceptionally-hard dolomite. The stone is so resilient, in fact, that preparing the rock away from the bones with tools and acid proved impossible. Nevertheless, the lower jaws of the early beaked whale