---

Some Saurischian dinosaurs (e.g., Apatosaurus (Brontosaurus) and Diplodocus) and all Ornithischian dinosaurs (e.g., Iguanodon and the duckbills, Stegosaurus, Protoceratops and Triceratops) were plant-eaters.

Eating a diet of plants causes animals many more problems than eating meat. Plants are made of tough materials like cellulose and woody lignin and need to be broken down before digestion can take place in the animal's stomach.

Plant-eating dinosaurs coped with their diet in a variety of ways:

• The Sauropods didn't chew at all, but swallowed raked-in vegetetation. This passed directly to the stomach and was ground up by deliberately swallowed gastroliths, or "gizzard stones," or was fermented by bacteria, as in a cow's stomach.
• Hadrosaurs had special teeth which to ground and chop their food before they swallowed it.
• A beak like the one used by Ceratopsians was ideal for tackling tough plants like the . Their lower, wider part of the bone (called the preentary) fitted tightly against the lower jaw.

---

Did they sit down to eat?

Does a rhinoceros sit down to eat grass, or a giraffe squat to nibble on low branches? No, and for good reason. A rhino's head is close to the ground because that's where all of its food grows. A giraffe's head is at the end of a long neck, close to leaves in trees.

---

To read about some plant eaters, click here.