This T. rex-Like Dino Was Vegetarian

A seven-year-old boy has just discovered a new dinosaur that was closely related to notorious carnivore Tyrannosaurus rex, but surprisingly ate a meat-free diet.

The 145-million-year-old dinosaur, Chilesaurus diegosuarezi, has been nicknamed "The Platypus" because of its extremely bizarre anatomy that was a mish-mash of features associated with huge carnivores, gigantic herbivores and nearly everything in between. It is described in the latest issue of the journal Nature.

The lifestyle of "The Platypus" contrasted with that of its relative, T. rex, which could likely rip the head off of other animals with a single bite.

"Chilesaurus probably fed upon ferns, araucarians, bennetitaleans, and podocarps -- all of which were plants that were abundant at the end of the Jurassic," lead author Fernando Novas of the Bernardino Rivadavia Natural Sciences Museum in Buenos Aires told Discovery News.

Diego Suárez, the son of two of Novas' co-authors, Rita de la Cruz and Manuel Suárez, stumbled upon the fossils of Chilesaurus while he and his sister Macarena were looking for decorative stones at the Toqui Formation in Aysén, south of Chilean Patagonia.

The researchers explored the area further and excavated even more fossils. At first they thought the bones belonged to multiple species, but they found four complete Chilesaurus skeletons, providing strong evidence that the combination of unique anatomical features belonged to a single species.

The dinosaur grew up to 10 feet long and was a member of the typically two-legged theropod group of dinos that included some of the world's most iconic meat eaters, such as Velociraptor and Carnotaurus, in addition to Tyrannosaurus.

Instead of chomping into meat, Chilesaurus could munch on plants either by directly accessing them via its long neck or by stuffing them into its horny-beaked mouth with its short T-rex-resembling forelimbs. Its leaf-shaped teeth could then chew the plant materials into a swallow-ready mass.

Novas and his team believe that the earliest theropods started off as carnivores before some evolved towards an all-plant diet. Chilesaurus wasn't the only such herbivore. Limusaurus also veered toward veggies, probably due to ecological pressures and because plants were likely abundant in its environment.

Other animals in Chilesaurus' ecosystem included small, meat-eating crocodiles and extremely large plant-eating dinosaurs, such as 50-foot-long Diplodocus.

While some theropod dinosaurs evolved into birds, Chilesaurus and its related plant-eating dino relatives experienced another fate.

"Theropods that evolved into herbivores finally went extinct without leaving descendants that switched into carnivores again," Novas said.

Read more at Discovery News