Study Shows Lots of Variation in Dinosaur Species

By | March 26th, 2021|Dinosaur and Prehistoric Animal News Stories, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

Researchers from the University of Bonn (Germany), in collaboration with colleagues from Liverpool John Moores University examined cranial material of the Plateosaurus species – P. trossingensis and discovered that the skulls of these dinosaurs demonstrated a high degree of variation. Just like people, this Plateosaurus species demonstrates a high degree of individual variation within a species.

Plateosaurus trossingensis fossil skeleton
Fossil of a Plateosaurus trossingensis, on loan from the Sauriermuseum Frick and on display at the Zoological Research Museum Alexander Koenig (ZFMK) in Bonn. Doctor Katja Waskow (left) from the Zoological Research Museum and on the right, Prof. Dr Martin Sander from the University of Bonn. Picture Credit: Volker Lannert/University of Bonn.

Not All Dinosaurs of the Same Species Looked Alike

Plateosaurus from the Late Triassic of Europe is one of the most extensively studied of all the dinosaurs, thanks mainly to the huge bonebeds containing thousands of fossilised bones that have been found. It is by studying the fossilised remains that palaeontologists can put forward evidence to suggest the erection of a new species. However, this new study published in Acta Palaeontologica Polonica, suggests that the anatomy of Plateosaurus was significantly more variable than previously thought.

A Plateosaurus dinosaur model.
A rearing Plateosaurus. A model of a Plateosaurus (CollectA Plateosaurus), this Late Triassic member of the Prosauropoda is one of the most extensively studied of all the Dinosauria.

Natural Variation

The researchers examined the complete skulls of fourteen individual Plateosaurus trossingensis specimens, eight of which had not been studied before, along with numerous other skull bones and discovered that there was considerable variation in the skulls. Such variation had been noted before and it had been suggested that the extensive bonebeds at Frick (northern Switzerland), Trossingen (south-western Germany) and Halberstadt (central Germany) might contain the fossilised remains of more than one species. However, the researchers which included PhD student Jens Lallensack (University of Bonn), could not group these variations according to specific anatomical traits, locality or their stratigraphy. The team concluded that there was no evidence to indicate the presence of more than one species, but these types of dinosaurs showed considerable variation within their species (intraspecific variability).

Plateosaurus trossingensis skull and drawing.
A Plateosaurus trossingensis skull in right lateral view with a colour coded diagram (below) showing individual fossil bones. Picture Credit: Jens Lallensack (University of Bonn).

Taking into Account Bone Deformation

The careful documentation of the skull variation will assist other palaeontologists when it comes to understanding the distinct individuality of dinosaurs within a given population. The team were able to distinguish these differences from those characteristics of the bones that are deformed and altered as a result of their fossilisation. Being able to attribute bone deformation due to taphonomy (the fossilisation process), is extremely useful in helping to determine unique anatomical traits that could lead to the identification of a new species.

Photograph (top) and a model of a deformed skull resulting from the fossilisation process (below)
Photograph (top) and a model of a deformed skull resulting from the fossilisation process (below). Picture Credit: Jens Lallensack (University of Bonn).

The scientific paper: “New skulls of the basal sauropodomorph Plateosaurus trossingensis from Frick, Switzerland: Is there more than one species?” by Jens N. Lallensack, Elżbieta M. Teschner, Ben Pabst and P. Martin Sander published in Acta Palaeontologica Polonica.