T.Rex’s ‘bizarre’ vegetarian cousin puzzles science

Chilesaurus diegosuarezi had a bird-like beak with leaf-shaped teeth, evidence that it feasted on plants, but with hind leg features similar to theropod dinosaurs, the group into which it was slotted with notorious killers like T. Rex, Velociraptor and the horned Carnotaurus.

“Chilesaurus constitutes one of the most bizarre dinosaurs ever found,” Fernando Novas of Argentina’s Natural History Museum in Buenos Aires told of a study published in the journal Nature which he co-authored.
“At the beginning, I was convinced that we had collected three different dinosaurs, but when the most complete skeleton was prepared, it (became) evident that all the elements pertained to a single dinosaur species.” 

The bizarre creature was named after the South American country where its fossilized remains were found, and the seven-year old boy, Diego Suarez, who discovered the first bones in 2004 while exploring the Andes mountains with his geologist parents.

Theropods like T. Rex tended to have relatively short necks, big heads and strong, muscled hind legs much bigger than their arms, vicious claws and jaws brimming with razor-sharp teeth. But Chilesaurus cuts an altogether less threatening figure.

Chilesaurus diegosuarezi lived at the end of the Jurassic period, some 145 million years ago, long before T.rex.