Fossilized Vomit Found in Utah Dates to the Jurassic Period

Paleontologists have unearthed the regurgitalite, or vomit, of a carnivorous predator that consumed smaller species dated to a million years ago.

What is a Bromalite?

Bromalites, which can be categorized as trace fossils, are the fossilized remains of material that came from an organism's digestive system, according to Wikipedia. The popular types include fossilized feces (coprolites) and fossilized remains of vomit or other regurgitated objects (regurgitalites), intestinal contents (cololites), and stomach contents (gastrolites).

While gastrolites and cololites are discovered in situ in their respective organs, regurgitalites and coprolites are only found after they have left the bodies of the producing organisms.

Bromalite Discovery in Utah

According to Live Science, during an excavation in the Morrison Formation in southeast Utah in 2018, scientists discovered a bromalite. The western United States is covered with a band of sedimentary rocks. Local paleontologists call it the "Jurassic salad bar" because it is rich in late Jurassic period fossils. Its name comes from the fact that it is made up of more fossilized organic material than animal bones, specifically plants and other organic materials.

The team, comprised of experts from the Utah Geological Survey, discovered a small pile of decaying remains less than one-third of an inch square. They said they knew they had found something remarkable when they saw it. The Palaios journal published a report on this occurrence.

According to the lead author, John Foster, what surprised them was the scant concentration of animal bones in a relatively small area. He claimed that there aren't typically any animal remains at the location. Only vegetation was there, and the bones they discovered were not dispersed across the rock but were centered on a single area instead. He said the bones they discovered were the first group they had ever seen.

Identifying the Fossilized Vomit

Foster recalled that at first, they believed the fossil they had found to be the remains of a single animal. However, they soon discover that the bones are not all from the same salamander and that some of them are mismatched.

When they looked closely, they discovered that the femurs were from a frog and that the bones belonged to at least one salamander. There were also vertebrae from one or more undetermined species. The researchers concluded that what they saw was vomited out by a predator.

Nearly a dozen bone fragments and a matrix of soft tissue fossils were discovered combined, according to the study. Foster described their discovery as unique compared to other regurgitalites' documented results worldwide.

However, an additional examination is required to identify other elements of the partially digested animals that the predator ingested. Unfortunately, it is impossible to determine precisely which species were consumed by their predators. Additionally, the reason that it was upchucked in the first place could not be determined.

Foster stated that they believe their discoveries to be more extensive than just the minute bones of amphibians. He claimed that by performing chemical analysis, they could start to exclude possibilities and establish exactly what the soft tissues are made of.