Artistic image of a puffin trying to sneak up on a frog floating on the surface of a pond while another cup fills part of the frog and newt’s recent diet. Puffins are the alleged predators of a 150-million-year-old vomit fossil found in southeastern Utah. (Brian Ing via the Utah Department of State Parks)
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VERNAL – A recently discovered fossil in southeastern Utah appears to show what kind of prey predators ate in the dinosaur age and when the area wasn’t desert it is today.
Paleontologists in Utah have unearthed a pile of amphibian bones that they believe appear to have been vomited by some kind of predator. This prehistoric vomit is thought to be 150 million years old, according to paleontologists from the Utah Geological Survey, the Utah Department of State Parks and the Flying Heritage & Combat Armor Museum in Washington.
Their discoveries were Published in Paleos magazine last month.
“This fossil gives us a rare glimpse of animal interactions in ancient ecosystems,” said John Foster, curator of the Utah State Field House Natural History Museum and one of the study’s co-authors, in a statement Tuesday.
The team found the fossil during the search Morrison training, a famous fossil site known for its late Jurassic fossils, ranging from around 148 million years ago to 155 million years ago. It is best known for its dinosaur bones, but it is also where scientists find all kinds of other animals, such as fish, salamanders and frogs.
The southeastern part of the Utah formation is largely characterized by prehistoric plants such as ginkgo, ferns, and conifers. However, paleontologists have also found amphibians and puffins there. This discovery is the reason they believe the area was once home to a pond or small lake.
But during a recent survey, the team found an oddly arranged fossil. It was a set of bones that included “elements” of at least one small frog or tadpole and would have been “the smallest salamander specimen reported of that formation,” the researchers wrote in the study. Some of these bones are only 0.12 inches long, among the smallest bone groups in the formation.
They added that the chemical composition and skeleton of the pit suggested it was regurgitation, a form of petrified vomit. The team noted that this was the first discovery in the Morrison Formation and the Jurassic of North America.
What remains unclear 150 million years later is what killed the species within regurgitalite. Foster noted that previous research placed puffins in the area at the time, which he considers the “best match to date” for the predator behind the fossil. Scientists have been discovering species of fish, salamanders and frogs in the Morrison Formation for more than a century.
“While we can’t rule out other predators, puffins are currently a suspect,” he said, explaining that fish – and other animals – sometimes regurgitate their last meal when being chased or want to distract a predator. .
“There are three animals that we still have today, which interact in a way that is also known between animals: the prey is eaten by a predator and a predator can be chased by another predator,” he added. “This in itself shows how similar some ancient ecosystems are to places on Earth today.”
The discovery is the latest made by a team from the region. Two of the study’s three co-authors also helped A huge 151 million year old water bug was foundwhich led to a document published in 2020.
State paleontologist James Kirkland, co-author of both studies, said paleontologists intend to continue searching the site where prehistoric vomit was found to see if they can find more evidence of past ecosystems in the area.
“I am very happy to have found this site, as vegetation sites from the Upper Jurassic are extremely rare,” he said in a statement. “Now we have to carefully dissect the site in search of other little wonders among the leaves.”
