This armored dinosaur is a paleontologist’s aspiration. Named Borealopelta in 2017, the dinosaur’s fossil preserves a great offer of its bony armor in location. In actuality, the animal is so intricately preserved that paleontologists have been equipped to work out the dinosaur’s shade — rusty purple higher than and lighter beneath. But the so-termed “northern shield” nevertheless has insider secrets to reveal. Inside of the dinosaur, guarded by its bones, are the remnants of the ankylosaur’s previous food.

Paleontologists know fairly little about what dinosaurs really had for lunch. For carnivorous animals, the vital evidence frequently will come from bitten bones and petrified poop that contains bone shards and muscle fibers.

Amongst herbivores, fossil feces can slim down a handful of menu solutions, but fossilized intestine contents have been far more contentious. It can be hard to inform no matter whether tatters of crops uncovered inside a plant-ingesting dinosaur’s skeleton ended up remnants of a previous food — or only happened to get blended in with the sediment that buried the animal. Just this yr, in actuality, the intestine contents uncovered in a duckbill dinosaur turned out to be prehistoric compost blended in among the bones all through preservation.

“Dinosaurs that turn into fossils frequently get buried in the mud or in river channels,” says Caleb Brown of the Royal Tyrrell Museum. These situation can make confounding associations of bones and the content inside, which might or might not be the contents of the petrified dinosaur’s belly.

But Brown says this specimen stands aside — and is the most effective-supported case for belly contents in an herbivorous dinosaur. “And it contains the most element about revealing what the diet was,” he provides. Brown and colleagues have published their review this week in Royal Culture Open Science.

A Dinosaur’s Final Meal

Borealopelta side view

The Borealopelta fossil on display at the Royal Tyrell Museum in Alberta, Canada. (Credit: Etemenanki3/Wikimedia Commons)

Out of 16 conditions that Brown and co-authors produced to establish no matter whether the crops ended up really intestine contents or not, Borealopelta matched 14 of the appropriate features.

And even with going as a result of the initially fifty percent of the dinosaur’s digestive tract, the plant content remained astonishingly very well preserved. “We embedded fragments of the belly content mass in resin, sliced them, polished them right up until translucent, and looked at them beneath the microscope,” Brown says. The crops ended up preserved down to the mobile stage, allowing the paleontologists to be far more specific about what kinds of veggies the ankylosaur ate. Prior to dying, Borealopelta wolfed down small-lying ferns, with some cycads and a little little bit of conifer thrown in.

“What I like about this review is that it confirms some of the suggestions proposed about several a long time about the typical style of food stuff ankylosaurs ended up ingesting, though giving us a substantially far more specific idea of the particular crops that produced up the diet of Borealopelta,” says Victoria Arbour, a paleontologist at the Royal BC Museum.

These dinosaurs ended up quadrupeds, with heads small to the ground and fairly weak jaws equipped with modest teeth. They did not have the amazing dental batteries of other dinosaurs of their time that would have authorized them to munch as a result of rotting logs or tough wooden.

Still, Brown says, there ended up some surprises. The absence of crops like horsetails in the intestine contents, and the rarity of conifer content, could seem odd supplied how widespread they ended up in the dinosaur’s habitat. It appears this Borealopelta was a thing of a picky eater.

“The most important shock for me was the charcoal,” Brown says, pointing to the modest quantity of burnt wooden that suggested this dinosaur was ingesting small-lying crops in an place that had not too long ago had a wildfire. In actuality, that association could make clear the presence of so lots of ferns. Arbour notes that ferns are some of the initially crops to grow in fireplace-influenced landscapes.

“It’s interesting to assume that this dinosaur might have at any time survived the wildfire that developed the charcoal it ate,” she provides, “only to fulfill its demise in a watery tomb later on on.”