How did dinosaurs rule the world for so long? This is a question that continues to vex scientists. A team of researchers has revealed that their diet may have played an important role. The information they read… in fossil drops!
If we are accustomed to represent. BiologistsBiologists Whether studying fossil bones or dinosaur footprints, the remains they are interested in are actually much more diverse. So, of course, we must admit that it is less appealing to say that we also study coprolites, in other words… fossilized excreta. And yet, the products of these items DigestionDigestion Of the long-extinct animals, it turns out to be extremely rich in information. They may even help us understand how dinosaurs were able to rule the world for so long.
” No such study has ever been conducted. », biologist Martin Kvarnström of Uppsala University commented in this article. ScienceSpeaking about the new study of which he is the lead author. ” People want to study large skeletons, not gray… » Results published. The nature Still they are talked about, and in a good way! Because it must be said that the approach is innovative.
Dinosaur excrement and regurgitation analyzed from every angle.
The first dinosaurs appeared about 230 million years ago, competing with another group of animals: the pseudocean, whose current representatives are crocodiles. While the latter seem well on their way to dominating the world, the situation will suddenly reverse. Dinosaurs diversified rapidly, gradually occupying all ecological niches. They would eventually establish their reign, which would last for 160 million years.
The reasons for this change have long been debated. If the bipedalism and agility of earlier dinosaurs were determining factors for some, then dinosaurs could have shown other advantages. For Qvarnström and his team, the diet of early dinosaurs could have played an important role. But how do we know what these animals ate 200 million years ago? By studying their excretion and regurgitation, of course! What could be more representative than these “bromalites” (the scientific term used to describe these fossilized remains resulting from digestion)?
They indeed contain countless clues about the dinosaur’s diet: insects, fish remains, plant remains, bones… 532 bromalites collected in Poland were thus sifted. In addition to chemical analysis, the precious remains were scanned (synchrotron microtomography) to determine what they were composed of and to associate them with various known species.
A very varied diet, the key to success
The researchers were thus able to observe the evolution of diet over time for each identified species, in relation to seasonal and environmental evolution.
It appears at first that the predecessors of the dinosaurs were basically All edibleAll edible and opportunistic, giving them greater ability to adapt than their competitors. Then, at the end of TriceTricethe ClimateClimate It gets hotter and more humid, allowing for lush vegetation that will encourage its spread. vegetarianvegetarian. The bromalites of the latter also indicate that their diet was very varied. They seemed to be able to eat a variety of plants, and even CoalCoal. An advantage that allowed them to replace the pseudochians and TreatmentTreatment vegetarian
An abundance of food would have favored the growth of very large sizes among gradual herbivores. This is how sauropodomorphs appear, whose weight can reach several tens of tons. In response to this morphological evolution of herbs, TheropodsTheropods CarnivoreCarnivoreLike the famous tyrannosaurus, will reach record sizes. Of this era giantgiant Definitely marks the beginning of the dinosaur age.
The study therefore shows the extent to which food diversity was an important factor in the evolution of dinosaurs. It also helps to better understand evolutionary processes in general.
