Recently, paleontologists in Poland have discovered fossils of dinosaur feces and vomit from 200 million years ago. Although these fossils may not be as massive as dinosaur skeletons, they play a crucial role in helping paleontologists reconstruct the lost world, such as understanding the dietary habits of dinosaurs and their ecological roles. This new discovery was published in the journal “Nature” on November 27.
“The most astonishing aspect is how well-preserved and diverse the food remnants inside the fossilized feces and vomit are,” said Martin Quivanshtrom, a co-author of the study and a paleontologist at Uppsala University in Sweden, to “Popular Science” magazine. “We found bones, teeth, fish scales, plant fragments, and even tiny beetles, providing insights into the dietary preferences of dinosaurs.”
These fossils were unearthed in Poland and trace back to the late Triassic and early Jurassic periods. During this time, all the land on Earth formed a supercontinent known as “Pangaea.” As this landmass started to break apart, internal seas brought moistures to previously arid climates.
Grzegorz Niedzwiedzki, a co-author of the study and a paleontologist from Uppsala University, explained, “By the late Triassic period, the Polish Basin became more humid, flourishing with fern plants and various moisture-loving plants that herbivorous dinosaurs enjoyed as their food source.”
Initially, the landscape was dominated by large amphibians and non-dinosaur reptiles, along with early mammals, turtles, and pterosaurs. However, around 200 million years ago, during the transition from the Triassic to the Jurassic period, dinosaurs began to rise to dominance, leading to the gradual extinction of other animal groups.
In this study, Quivanshtrom, Niedzwiedzki, and other paleontologists from Norway, Poland, and Hungary examined over 500 feces fossils. They utilized advanced synchrotron imaging techniques to meticulously analyze the internal components hidden within the fossilized feces. By combining climate data and information from other fossils, they identified undigested food remnants of plants and animals to reconstruct the ecosystem structure during the rise of dinosaurs in the northern regions of Pangaea.
“I believe that dinosaurs thrived in this world, wandering on massive riverbeds, searching for the best feeding grounds,” Niedzwiedzki said. “Scenarios of herbivores being ambushed by predators occasionally likely happened, as evidenced by 15-inch-long claw marks from predators scattered around.”
Some feces fossils contained remnants of fish, insects, large animals, and plant debris. Other fossils showed bones chewed by predators, who would crush bones to access salts and marrow similar to modern-day hyenas. Feces from sauropod dinosaurs, among the earliest herbivorous dinosaurs, were rich in tree ferns and other plant types.
“In one of the feces fossils we found, remarkably well-preserved plant remnants were present, with various structures of cells and leaves clearly visible,” Niedzwiedzki remarked. “These plants likely passed through the dinosaur’s digestive tract, possibly preserved well due to bacterial action.”
Traces of charcoal were also found in the feces of herbivores. The research team speculated that sauropod dinosaurs may have consumed charcoal to detoxify certain substances in their stomachs, as fern plants could be toxic to herbivores.
According to the team, this research fills a 30-million-year gap in our understanding of dinosaur evolution. While we have abundant knowledge about their lives and extinctions, we know little about the ecological and evolutionary processes that led to their successful emergence as a species.
“Understanding the process that led to the rise of dinosaurs over two hundred million years ago may seem distant, but it is incredibly fascinating and closely relevant to today,” Quivanshtrom explained. “Understanding how dinosaurs ascended to dominance tells us about the long-term effects of climate change and extinction events. These ancient patterns can help us better comprehend the challenges of current and future climate change and species extinction.”