In the Belly of This Beast, a Major Find

Scientists have long believed that the enormous, long-necked sauropods—like those popularized in films such as Jurassic Park and The Land Before Time—were herbivores. Researchers had some clues based on teeth shape and an unwieldy body that didn't suggest these dinosaurs could chase prey well, but hard proof was missing. Now, a new study in Current Biology offers what appears to be the first direct evidence: actual fossilized plant matter preserved in the gut of a sauropod.

• The discovery centers on a 36-foot-long juvenile Diamantinasaurus matildae named Judy, excavated in 2017 from the Winton Formation in Queensland, Australia, reports the New York Times. Led by paleontologist Stephen Poropat and the Australian Age of Dinosaurs Museum team, scientists found a layer of fossilized plant material, known as cololites, near Judy's pelvis.

• The rarity of cololites, especially in plant-eating dinosaurs, made the find significant. Further analysis revealed the plants didn't simply wash in to the body—the plant fossils were found with a layer of fossilized skin, strengthening the case they were in the gut at the time of fossilization.
• Analysis of Judy's cololites hinted at a varied diet, showing remains from conifer trees and flowering plants. The leaves were impressively preserved, leading Poropat's team to conclude that sauropods swallowed their food whole without chewing, relying on gut bacteria to digest it over a week or two.
• Experts note the findings support long-standing ideas that sauropods ate a wide variety of plants and weren't picky about what they ate—necessary, perhaps, for sustaining such massive bodies.
• Judy is just one dinosaur, and Poropat concedes that what may have been this particular dino's final meal doesn't necessarily speak for the dietary habits of all sauropods, per a release. But researchers say this single, well-preserved cololite offers rare insight into what these giants actually ate and how they processed food.