We now know that dinosaurs were giant reptiles that dominated the Earth, but scientists have long wondered why it took them 30 million years to reach their peak. New research on their fossilized poop and vomit may have found the answer suggests that there was food in their waste.

Carnivorous dinosaurs like tyrannosaurus may have their herbivore ancestors to thank for their enormous size. The researchers propose that if these plant-eating animals hadn’t ingested so many plants, dinosaurs might not have evolved into the giant creatures we know today.

The fossilized poop and vomit, known as bromalite or copralite, dates back to around 230 to 200 million years ago, a time long before the reign of the tyrannosaurus and the Chicxulub asteroid impact that led to the extinction of dinosaurs.

Scientists reconstructed a “food web” from the undigested meals of early dinosaurs, revealing the intricate relationships between different species during the Triassic period. By scanning over 500 fossils, they found evidence of various organisms, including beetles, bones, and partially digested fish.

Combining this information with climate data and other fossils provided insights into the diverse flora and fauna coexisting with dinosaurs on Earth.

“Sometimes seemingly ordinary fossils contain remarkable information that cannot be found anywhere else,” said Dr. Martin Kvarnström, a study co-author from Uppsala University in Sweden, as reported by BBC Science Focus.

Dr. Grzegorz Niedzwicki, another co-author from Uppsala University, added, “Understanding the diet of early dinosaurs may help us grasp why this group thrived. The evolution of life on Earth hinges on predator-prey dynamics and feeding habits.”

A study published in Nature analyzed digestive samples from south-central Poland during the Late Triassic period when the region was part of the Pangea supercontinent.

According to experts, increased volcanic activity and humidity favored the growth of moisture-loving plants during this time, potentially influencing the evolution of dinosaurs.

The study utilized advanced scanning techniques to reveal detailed information from the fossils, highlighting changes in vertebrate populations leading up to the dominance of dinosaurs.

The researchers aim to apply this model to study ancient species in other regions and emphasize the importance of fossilized waste in reconstructing ancient food webs.

“Everyone is focused on finding fossilized skeletons, but it’s the waste that offers valuable insights into events from millions of years ago,” remarked Niedzwicki.

About our experts:

Dr. Martin Kvarnström is a researcher at Uppsala University in Sweden, focusing on using fossils to understand reptile diets, including dinosaurs.

Dr. Grzegorz Niedzwicki, also from Uppsala University, specializes in the early evolution of dinosaurs and other quadrupeds.

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