Dinosaurs certainly tested everything mattermatter of morphologymorphology and, in particular, means of protection. In a world where super-predators lurked in every corner of the forest, it was indeed better to be well protected when you were an herbivore, even if you weighed several tons.
Many species of dinosaurs thus present a whole battery of defenses ranging from horns, claws, clubs to the ends of tails or dorsal spines. But one of the most effective was certainly the armor worn by the famous ankylosaurs and their relatives.
A layer of keratin covering bone armor
The fossil of a nodosaur, a herbivore more than five meters long and part of the cladeclade ankylosaurians, has also revealed the incredible performance of this protective armor. On this extremely well preserved fossil dating from the beginning of the CretaceousCretaceous (around 110 million years), researchers have indeed found remains of keratinkeratinthe same material our hair and nails are made of. A notable finding because keratin does not tend to be properly preserved during the process of fossilisationfossilisation.
Until now, it was thought that the main protection of ankylosaurs and nodosaurs was provided by a structure of bony plates that they wore on their of theof the and that only a thin layer of keratin would have covered it. The petrified nodosaur discovered in 2017 in a mine in Alberta, Canada, however, reveals that this layer of keratin was in reality much thicker, and that it would have played a very important protective role.
A real chain mail
The bony armor of nodosaurs would thus have been covered with a layer of keratin 16 centimeters thick, which would have acted like real chain mail. As reported in this article in LiveSciencesimulations revealed that the animal could thus have withstood a force equivalent to that of the impact of a carcar launched at full vitessevitesse ! This double protection would have ensured these dinosaurs survival against predators capable of inflicting powerful bitesbites.
These results were presented by Michael Habib on October 30, 2024, during the congress of the Society for Vertebrate Paleontology.
