Sometimes, the most important scientific discoveries come from the least glamorous places. In a new international study published in Scientific Reports, Brandon University paleontologist Dr. Mark MacDougall helped identify what may be the oldest known example of fossilized vomit from a land-dwelling predator, dating back nearly 290 million years.
Dr. Mark MacDougall
Yes, really. Dinosaur barf.
More accurately known as a regurgitalite, the fossil was discovered at the famous Bromacker fossil site in Germany and represents the preserved remains of a prehistoric predator's rejected meal. Unlike fossilized poop (coprolites), this specimen contains partially digested bones that were thrown up rather than passed through, and it's the earliest confirmed example from a fully terrestrial ecosystem.
"This fossil is extremely important for understanding how early land ecosystems worked," says Dr. Mark MacDougall, Assistant Professor of Biology at Brandon University and a co-author on the study. "It's rare to get such direct evidence of who was eating whom nearly 300 million years ago. In this case, the predator clearly bit off more than it could stomach."
Using CT scanning and chemical analysis, the research team identified bones from at least three different animals inside the regurgitated cluster, including a small reptile, a fast-moving lizard-like animal, and part of a much larger plant-eater. All signs point to a top predator, likely an early relative of mammals such as Dimetrodon, gulping down a mixed meal and later coughing it back up.
Modern animals, from owls to wolves, do the same thing when bones or other tough bits prove too hard to digest. Finding evidence of this behaviour so far back in time gives scientists a rare snapshot of feeding behaviour, food webs, and predator-prey relationships in one of Earth's earliest land ecosystems.
"This is like a prehistoric time capsule," MacDougall adds. "These animals lived together, died together, and ended up in the same regurgitated pile, probably within days of each other. That kind of detail is incredibly rare in the fossil record."
The study was led by researchers from the Museum für Naturkunde in Berlin and France's CNRS, with Brandon University playing a key role in interpreting the fossil and its ecological meaning.
Dr. Chris LeMoine, Dean of Science at Brandon University, says the discovery highlights the global impact of BU research. "This project highlights how Brandon University researchers are collaborating with colleagues around the world to contribute to significant fundamental discoveries," says LeMoine. "It's rigorous science, creative thinking, and yes, sometimes a bit messy. That's how we expand our understanding of the natural world past and present."
The research also reflects Brandon University's broader commitment to curiosity-driven research and knowledge sharing. Dr. Bernadette Ardelli, Vice-President (Research & Graduate Studies), notes that even unusual discoveries play a vital role in public engagement with science. "This study reminds us that research doesn't have to be intimidating to be meaningful," says Ardelli. "Whether it's dinosaur barf or breakthrough technology, Brandon University research helps people connect with science, and see how discovery can come from asking unexpected questions."
Beyond the novelty, the finding provides the first direct evidence of opportunistic feeding behaviour in an early land-based apex predator and helps scientists better understand how complex food webs evolved long before dinosaurs roamed the Earth.
And yes, it also proves that even 290 million years ago, some meals just didn't sit right.
Rebillard, A., Jannel, A., Marchetti, L., MacDougall, M.J., et al. (2026). Early Permian terrestrial apex predator regurgitalite indicates opportunistic feeding behaviour. Scientific Reports.
