Most reptiles are carnivorous, meaning they eat other animals. There are a small number of reptile species however, that do eat plants for survival. Reptiles have highly developed predatory instincts as well as reflexes to aid them in catching their prey.
Reptiles of the crocodilia order (alligators, crocodiles, caimans and gharials), eat raccoons, rabbits, water birds, pigs and sometimes their own species, if they are smaller than they are. A large alligator has enough power to take down a deer, for its meal.
Testudines eat both plant and animal. Tortoises mainly eat plants, while turtles will eat either one. Turtles will eat duckweed, algae, eggs, larva, insects, crayfish, mollusks and some will species will even eat jellyfish. Turtles do not have teeth, therefore their jaws have horny, tough plates for holding on to their food.
Snakes and lizards are of the squamata order of reptiles. A few lizard species only eat plants, but most eat other reptiles, insects, snails and spiders. Lizards are equipped with a special mobility of their skull, which allows them to grasp and hold their prey firmly. This special mobility also increases their jaw closing force. Snakes on the other hand eat birds, frogs, insects, lizards, salamanders, rodents, eggs, fish, mammals and other snakes. Snakes are able to swallow prey that is several times its own size. They are able to do this by dislocating their jawbone from their skull. Non-venomous snakes squeeze to death than swallow it. Poisonous snakes inject poison into their prey with their fangs, in order to keep them from struggling. Pit viper snakes have heat sensitive pit organs on their head that allows the snake to track warm-blooded prey and aim their strike.
Tuataras mostly eat insects and love beetles. However they have been know to eat birds and bird eggs as well as other lizards. The young tuataras will hunt for their food during the day, so as not to be eaten by the adult tuataras who hunt at night. Tuataras have one row of teeth on their lower jaw and two rows on the upper. There teeth placement makes it easy for them to tear apart their food.