Regurgitated material contains prey of hunter who lived before dinosaurs
Two hundred and ninety million years ago, in a mountain valley in the central region of the supercontinent Pangea, an apex predator grabbed at least three other animals and vomited up the bones some time later.
This material has hardened over time and today constitutes the oldest fossilized vomit ever discovered in a terrestrial ecosystem. The pile of bones and digestive material provides rare information, published January 30 in Scientific reports, about the behavior of some of the world’s first terrestrial predators.
“It’s a bit like a photograph of a moment from the past which tells us about the animal that lived,” explains Arnaud Rebillard, paleontologist at the Museum für Naturkunde in Berlin. “Any data we can find on their behavior is very valuable.”
Paleontologists discovered the lime-sized specimen in 2021 at a site called the Bromacker locality in central Germany. The researchers then scanned the bones to create 3D models showing a group of parts from different animals, suggesting they came from the gut of a predator. They also chemically analyzed the material surrounding the bones and found that it was low in phosphorus, suggesting that it was not fossilized dung.
today’s monitor lizards like the Komodo dragons: Dimetrodon teutoniswith a prominent sail on the back, and Tambacarnifex unguifalcatus. Although reptilian in appearance, both belong to a group of animals called synapsids that includes mammals and their extinct relatives.Among the 41 disgorged bones, researchers were able to distinguish two small lizard-like reptiles and a limb bone from a larger reptile-like herbivore. This collection of remains, along with several unidentified bones, indicate that the predator ate whatever it could find rather than specializing in a specific type of prey.
Because the fossilized vomit, or regurgitalite, contains three different animals eaten by the same predator, “we can literally say, with certainty, that these three animals lived in the exact same place and at the exact same time, perhaps every week or even every day,” Rebillard says.
Many living predators usually regurgitate bones and other hard-to-digest body parts after eating. Scientists don’t know if that’s why the ancient animal spat out its bones, but it’s one of the most plausible explanations, along with simply eating too much, Rebillard says.
Fossils of partially digested material, including regurgitations, as well as fossilized excrementare valuable clues for studying the Earth’s past. “We need fossils like this to really connect ecosystem functioning and food web structure,” says Martin Qvarnström, a paleontologist at Uppsala University in Sweden, who was not involved in the new study.
German Regurgitality is particularly interesting because the Bromacker site preserves a snapshot of a primitive terrestrial ecosystem. Older predators that could move on land often lived in semi-aquatic environments where they hunted crustaceans and fish. The Permian period represents a time when large herbivores became predominant in interior environments, followed by new predators. Fossil feces and vomit are much rarer in inland environments than in aquatic environments.
“We’re talking about ecosystems that are almost 300 million years old,” says Rebillard. “So to have such a temporal view of the time they lived in, in the same region and at the same time, is extremely fascinating.”
