The Baryonyx

Jan 14, 2008 11:10 GMT  ·  By

We are more familiarized with the ferocious meat-eating dinosaurs, like T-rex. But some appear to have been skilled fishers, too! Baryonyx was found in 1983 near Dorking in Surrey, UK. It was 125 million years old, and was classified to the family of spinosaurs. The beast was up to 10 m (33 ft) long and weighed up to 2 tonnes.

The odd look of these dinosaurs pointed that they might have eaten fish. But a new research, using computer modeling techniques, clearly revealed that its skull worked like that of a fish-eating crocodile, even if the animal resembled the T-rex. The two huge hook-like hand claws could have been used for dragging fish out of the water. When Baryonyx ate, its skull appears to have made exactly the same movements like that of the Indian gharial, a long narrowed-jawed crocodile, world's most adapted to a fish diet.

"On excavation, partially digested fish scales and teeth, and a dinosaur bone were found in the stomach region of the animal, demonstrating that at least some of the time this dinosaur ate fish. Moreover, it had a very unusual skull that looked part-dinosaur and part-crocodile, so we wanted to establish which it was more similar to, structurally and functionally - a dinosaur or a crocodile", said lead author Dr. Emily Rayfield, of the University of Bristol, UK.

"We used an engineering technique called finite element analysis that reconstructs stress and strain in a structure when loaded. The Baryonyx skull bones were CT-scanned and digitally reconstructed so we could view the internal anatomy of the skull. We then analyzed digital models of the snouts of a Baryonyx, a theropod dinosaur (like T-rex), an alligator, and a fish-eating gharial, to see how each snout stressed during feeding. We then compared them to each other."

The feeding movements of Baryonyx were significantly different from those of a typical meat-eating dinosaur or an alligator, being extremely similar to the gharial's.

"The CT-data revealed that although Baryonyx and the gharial have independently evolved to feed in a similar manner, through quirks of their evolutionary history their skulls are shaped in a slightly different way in order to achieve the same function. This shows us that in some cases there is more than one evolutionary solution to the same problem", said co-author Dr. Angela Milner. from the Natural History Museum, who first described the dinosaur.

Baryonyx has a very elongated skull, with a sinuous jaw edge, like in crocodiles and alligators, and stout conical teeth, not the blade-like serrated ones in carnivorous dinosaurs, and a remarkable bulbous jaw tip bearing a rosette of teeth, a trait also found in ... the living gharial!

Photo Gallery (2 Images)

Baryonyx
Gharial
Open gallery