Fossil permits peek inside a Dinosaur

A fossil of a primitive ceratopsian called Psittacosaurus has provided scientists with a glimpse of what these dinosaurs were like in the flesh.  Research published in the scientific journal of the Royal Society outlines the work carried out to study the fossilised skin of this small Cretaceous dinosaur.

It is rare for soft tissue such as skin to be fossilised but recently the discovery of a mummified hadrosaur in America has provided scientists with an opportunity to examine the hide of a dinosaur in detail.

To read the article on the dinosaur “mummy”: Mummified Dinosaur unlocks Duck-Billed Dinosaur Secrets.

Psittacosaurus

It is not clear whether Psittacosaurus was covered in primitive feathers called proto-feathers, this has yet to be determined and more finds will be required but this latest discovery reveals that this little dinosaur was a “tough cookie” with a thick, scaly skin composed of 25 layers of collagen similar to modern sharks and dolphins.  Palaeontologists believe this tough, outer coating supported the dinosaur’s organs and protected it from predators, although it could also have helped insulate this relatively small dinosaur and keep it warm.

Puncture marks on the fossil, identified as teeth marks indicate that the dinosaur’s carcase was torn open by another dinosaur, the carcase was soon buried by fine sediments and the folded skin was preserved.

Psittacosaurus was a small dinosaur, an early ancestor of the horned dinosaurs such as Triceratops.  The name means “parrot lizard” in deference to the parrot like beak this animal possessed.  This beak, was supported by a single median bone called the rostral bone – it is the one feature that distinguishes ceratopsians from all other dinosaur families.  The hind-limbs were slightly longer than the forelimbs.  This suggests that Psittacosaurus probably adopted a four-footed stance but could if required, such as when attempting to escape from predators, run on its hind legs.

Many Psittacosaurus Fossils are Known

Something in excess of over 400 specimens of Psittacosaurus are known from the fossil record, representing at least ten species.  Fossils have been found in Mongolia, Russia and China with further reported finds in Thailand.  Although not as well known as other ceratopsians such as Protoceratops and Triceratops, Psittacosaurus fossils are extremely important to palaeontologists as individuals of varying ages have been found.  This has helped scientists piece together how these animals changed and grew from hatchlings to fully grown adults.  The study of how a creature grows and changes over its lifetime is called ontogeny.

Psittacosaurus (right) and Protoceratops (left)

Picture credit: Everything Dinosaur

The models in the picture have been taken from the Feathered Dinosaur Models, available from Everything Dinosaur.  These models were originally designed by scientists from the American museum of Natural History.

To view the Feathered Dinosaurs and other prehistoric animal models: Dinosaur and Prehistoric Animal Models.

Commenting on this exciting discovery, Professor Theagarten Lingham-Soliar of the University of KwaZulu-Natal stated: “as noted from the studies on modern-day animals, this fibre structure plays a critical part in the stresses and strains the skin may be subjected to and is ideally suited to providing support and protection”.

Psittacosaurus, may not be the biggest dinosaur, it may not be the most popular amongst young dinosaur fans but it has provided some of the most exceptional fossils from the Mesozoic.  This new research provides further insight into the anatomy of dinosaurs, once again it is the little psittacosaur, that has got palaeontological circles buzzing.

The discovery last year of a “dinosaur den” containing the fossils of a group of juvenile psittacosaurs provided palaeontologists with a tantalising glimpse of the social life and behaviour of these little dinosaurs.

Psittacosaur nursery article: Dinosaur Nursery Unearthed in China.