Hundreds of millions of years ago, a carnivorous creature got into a feast of prehistoric amphibians and then threw up its meal.
Now paleontologists have discovered the regurgitation and published the findings of the ancient upchak.
In 2018, researchers excavating the Morrison Formation in southeastern Utah discovered regurgitalite—the fossilized remains of animal stomach contents—also known as bromalite.
Stretching across the western United States, these sedimentary rocks are a hotbed for fossils from the Late Jurassic (164 million to 145 million years ago).
In particular, this section, called the “Jurassic salad bar” by local paleontologists, usually contains the fossilized remains of plants and other organic matter, rather than animal bones.
So when a team that included researchers from the Utah Geological Survey (UGS) came across a “compact little pile” of retched remains no larger than a third of a square inch (1 square centimeter), they knew they were on to something. In particular, scientists said in a study published on August 3. 25 in the magazine palaios.
“What surprised us was this small concentration of animal bones in a relatively small area,” lead author John Foster, curator of the Utah Field Museum of Natural History State Park in Vernal, told Live Science.
“There are normally no animal remains in this area, only plants and the bones we found are not scattered. [amongst the rock] but they were concentrated in this one place. These are the first bones we saw there.”
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At first, the team didn’t know they had found prehistoric vomit. Instead, scientists thought they had discovered the bones of a creature “until they realized some of them looked wrong and not all of them were from a salamander,” Foster said.
“Up close, most of the material is from a frog and at least one salamander. That’s when we began to suspect that what we were seeing was vomited up by a predator.”

These fossils include amphibian bones, especially a frog and salamander, as well as vertebrates from one or more unknown species.
According to the study, several bone fragments were found together with a matrix of fossilized soft tissues.
Unlike coprolites (fossilized feces), this regurgitation is not fully digested, leading researchers to identify it as regurgitalite.
Although there are a number of recorded regurgitalite finds around the world, Foster said this is the first such find in the Morrison Formation, calling the discovery “one of a kind.”
While there’s no way to know for sure which animal species lost its lunch millions of years ago, or why it went down in the first place, further analysis can identify other components of partially digested animals that the predator ingested.
“We think there’s more to this thing than small amphibian bones,” Foster said. “By doing a chemical analysis, we can start to rule things out and determine exactly what the soft tissues are made of.”
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This article was originally published by Live Science. read it original article here.