A team of Chinese paleontologists discovered a new dinosaur species, Archaeocursor asiaticus, in southwestern China, offering fresh insights into the early evolution of ornithischian dinosaurs in ...

It is an ornithischian that lived on Earth 193 million years ago. "Along with other non-avian dinosaurs, they faced extinction at the end of the Cretaceous, while their early evolutionary history ...

Millions of years of evolution later, you can see the difference. Ornithischian dinosaurs like Triceratops and Stegosaurs, lacked these air sacs. And as a result most of them weren’t very big.