When we talk about “The Age Of Dinosaurs,” we think of an era where these enormous beasts ruled the land, but that wasn’t always the case. Like all animals that have lived to taste the upper echelons of the food chain, dinosaurs had to work their way to the top by outcompeting those that came before them. So, what triggered that rise?

A new study has tapped into the question in revealing that a boom in plant diversity may have given rise to heftier herbivores, which in turn made it possible for the big carnivores to come along. It’s a fascinating story, and one that’s sure to be a pivotal weapon in getting kids to eat their vegetables.

Studying dinosaur stomach contents

Studying the diet of extinct animals can be tricky, as finding stomach contents in-situ is rare in animal fossils, though we do have some incredible exceptions. Where else can you look for answers? All you need is some vomit, feces, and a bit of detective work.

“Studying undigested food remains and piecing together ‘who ate whom’ in the past is true detective work,” said lead author Martin Qvarnström of Uppsala University in a statement provided to IFLScience. “The ability to examine what animals were eating and how they interacted with their environment provides invaluable insights into what enabled dinosaurs to reach supremacy.”

When new floras evolved as a response to changing climates, the dinosaur herbivores seemed to have been better adapted to take advantage of the new resources.

Martin Qvarnström

Collectively known as bromalites, preserved stomach contents can be divided into regurgitalites (vomit) and coprolites (poop), revealing trace fossil evidence of what an animal ate in life.

Those studied in this latest research span the Late Triassic to the Early Jurassic, meaning some are over 200 million years old. Despite their impressive age, they contain beautifully preserved specimens including tiny beetles and fish, as well as the crushed up bones of larger animals.

Some of the stomach contents proved to be surprising, including that of the early herbivorous dinosaurs known as sauropodomorphs. It seemed they had been munching on large quantities of tree ferns, which can be toxic even to herbivores. However, they also appeared to be eating charcoal, a known detoxification agent we use in modern medicine. Clever veggie dinosaurs.

How did the dinosaurs rise to power?

As for the big question: how did the dinosaurs rise to power? It seems that eating more plants appears to have been a crucial step that saw the herbivorous dinosaurs outcompete the four-limbed vertebrates that came before them.

“Early herbivorous dinosaurs in the Polish Basin fed on a larger variety of plants than previous, more specialised non-dinosaur herbivores,” Qvarnström told IFLScience. “When new floras evolved as a response to changing climates, the dinosaur herbivores seemed to have been better adapted to take advantage of the new resources.”

Increased volcanic activity contributed to the diversification of plant species, providing more food that led to bigger and more diverse herbivorous dinosaur species. This also gave the meat-eaters a helping hand as they found themselves with much larger prey on the menu, and as they got bigger and more powerful in tandem, the dinosaurs clawed their way to the top.

The findings, which were taken from bromalite samples collected over 25 years ago, address a 30 million year gap in our knowledge of how the first dinosaurs evolved during the Late Triassic. Shining a light, for the first time, on the evolutionary and ecological processes that helped them along the way.

“What to do to not die out[?]” said senior author Grzegorz Niedźwiedzki in the statement. “Eat a lot of plants, a bit in the spirit of the slogan ‘eat your veggies and live longer’ which is exactly what early herbivorous dinosaurs did. The reason behind their evolutionary success is a true love for green and fresh plant shoots.”

BRB, off to eat a salad.

The study is published in the journal Nature.