Ornithischians

Ornithischians, on the other hand, are divided into four groups:

• Ornthitopods
• Stegosaurs
• Ankylosaurs
• Ceratopsians.

Ornithiscians were plant-eaters and lacked teeth that could defend them and so, had to resort to other means to protect themselves from meat-eaters like T Rexes and Velociraptors.

Stegosaurs had bone plates along their backs and tails that were armed with spikes to help fight off enemies.

Ankylosaurs, also referred to as armored dinosaurs had large masses of bone at the end of their tails for clubbing other animals in with. They also had spiky bone ridges on their backs for protection.

Ceratopsians had horns with which to gore a Theropod with whenever the need came up.

It’s also worth mentioning that ornithischians were different in another respect-they could chew, just like humans and some mammals (mostly herbivores) can. Now, not a lot of people notice but this, but some mammals like lions, wolves and many other carnivores can’t chew their food-they just bite it into sizeable chunks and swallow it whole. You on the other hand can chew food up as much as you want to.