Ornithischian dinosaurs , or "bird-hipped" dinosaurs, represent one of the two primary orders of dinosaurs. Despite the name, they are not the direct ancestors of modern birds—those actually evolved from the "lizard-hipped" saurischian group. This diverse group was almost exclusively herbivorous and is famous for its elaborate physical adaptations, including horns, armor, and complex chewing mechanisms. Key Defining Features
: A backward-pointing pubis bone, parallel to the ischium, likely evolved to accommodate a larger digestive system for processing plants.
: A unique, beak-like bone at the tip of the lower jaw used for cropping vegetation.
