Sauropodomorphs included ground-shaking giants like Apatasaurus, and ornithischians included a range of dinosaurs, such as Stegosaurus and Triceratops.
BBC: T.rex 'little cousin' discovered
2.
He explained that it filled a gap in the fossil record, demonstrating that dinosaurs split into their three major groups - theropods, sauropodomorphs and ornithischians - very early in their evolution.