TECH

Scientists find last fossilized dinosaur meal in their stomach 

In 2011, miners working in northern Canada were surprised to find a huge fossil of the upper half of a fairly preserved dinosaur (as you can see in the photo above). In 2017, researchers confirmed that it was a nodosaur, a species that belongs to the group of ankylosaurs or "armored dinosaurs", so called because of the thick bone carapace present on its back. Now, a new study of the same fossil has revealed a striking and unusual detail: the last meal that dino made before he died is still preserved.
The team spent years analyzing the inside of the fossil of more than 1,300 kg and found that the stomach was the most preserved ever found in a dinosaur so far. The organ is so preserved that, 110 million years after its death, its content is still practically intact, since it was also fossilized when the dinosaur died and its body ended up in the sea, where ocean rocks enveloped it and preserved it through history. So, for the first time, researchers were able to literally see the diet of a dinosaur taken directly from its stomach.
It was previously known that the dinosaurs of this group were herbivores, but details about their diets were, at best, directed speculation. Now paleontologists have concrete proof of what at least one species of them ate in their day to day life. Analysis of the material showed that the animal had a food preference for leaves of a specific species of Fern: 88% of the material found was formed from it. The remainder consisted of seeds, pieces of branches and trunks of at least 50 different plants, of various types, including from mosses to flowering plants (angiosperms). One fact surprised the researchers: the animal seemed to largely ignore an ingredient that scientists assumed to be part of its diet because of its abundance at the time: the leaves of conifers (a group that includes, for example, pine trees). Only a few remnants of this material were found in the stomach of the reptile.
In addition to the varied vegetable diet, the researchers also found a curious element in the dino's stomach: the so-called gastroliths, stones purposely swallowed by animals to help in the crushing and digestion of food in their stomachs. Crocodiles and seals are some modern animals that maintain this practice, and it was already theorized that several species of dinosaurs also use the resource.
Scientists also found pieces of burnt vegetation on the stomach of the animal, which was considered intriguing. The team does not know whether the consumption of this "coal" was accidental or purposeful. Some herbivores living in areas of constant natural fires have adapted to consume remains of burnt vegetation in their diets, but it is not known if this is the case with nodosaurus – even because the amount found was too small to assert itself with certainty.
Although pioneering, the study published in the journal Royal Society Open Science does not claim to generalize the fossil diet to all dinosaurs of the time, nor to their relatives: ankylosaurs were many and inhabited all continents, including Antarctica, which probably meant that they had different diets depending on the locality. 

Bruno Carbinatto-Brazil