A new study suggests that some ankylosaurs preferred a lonesome life because of their inferior sense of hearing
Using modern methods of investigation like micro-CT, scientists from Germany and Austria, looked at the braincase of an Austrian dinosaur and found that it was deaf and slow moving as per a report in scitechdaily.com.
The findings of the study were published in Scientific Reports.
The dinosaur that was studied was ankylosaurs which is also called “living fortress” and this was not without a reason as this group of herbivorous dinosaurs’ body length could go up to eight metres and it had spikes and bony plates. Certain members of this group like the ankylosaurids even at times had a tail which was like a club and some others like nodosaurids were blessed with spikes on their shoulders and necks. Yet there are many lifestyle aspects of this group that continue to puzzle scientists.
Most of the dinosaurs preferred to live in groups but there were some ankylosaurs who tended to lead a solitary life which was due to their inferior faculty of hearing.
The Greifswald and Vienna scientists using a high-resolution computer tomography produced a digital three-dimensional cast of the Austrian dinosaur and by scrutinising it they came to this conclusion.
What once housed the brain and other neurosensory tissues, namely the fossil braincases are vital for scientific investigation as their study reveals several aspects about the creature like their lifestyle. Take the case of inner ears which provides insights about the skull orientation and auditory capacities.
The scientists for their study chose struthiosaurus austriacus. This creature was a small nodosaurid and belonged to the Late Cretaceous period of Austria and was found from a locality close to Muthmannsdorf, south of Vienna. This dinosaur fossil was part of the collection of the Institute for Palaeontology in Vienna in the 19th Century.
Marco Schade from the University of Greifswald, Cathrin Pfaff of University of Vienna along with their colleagues investigated the braincase which was tiny -- 50 mm -- to discover fresh features about the lifestyle and anatomy of Struthiosaurus austriacus. The points observed provided them with new insights about the animal’s sense of audition and equilibrium.
What the study unveils is that the brain of Struthiosaurus austriacus was quite alike to that of its close relatives. For instance, the evolutionary old part of the brain, the flocculus, was quite small. Now this part is salient for the fixation of the eyes when the head, neck and whole body are in motion and is convenient for the creature when vying with prospective aggressors or competitors.
Expressing his views, Marco Schade said: “In contrast to its North American relative Euoplocephalus, which had a tail club and a clear flocculus on the brain cast, Struthiosaurus austriacus may rather relied on its body armour for protection.”
The unusual sluggish lifestyle of this plant eater comes across when flocculus is considered in tandem with the form of the semicircular canals in the inner ear. Moreover, the researchers discovered the shortest lagena of a dinosaur so far. Lagena is a part of the inner ear and it is here that audition takes place and size provides clues about its auditory capacities.
The study assumes importance as it helps in gaining fresh perceptions about the dinosaurs, their evolution and the world they lived – a planet in which a large portion of Europe was inundated by the ocean.