|Rodents are a very diverse order that include the large capybara, squirrels, beaver, chinchillas as well as porcupines and of course rats and mice. Rodents have enlarged chewing muscles that allow their jaw to work in a vertical, forward and backward motion. Only the front surface of the incisors has enamel, the back is softer dentine. This arrangement allows the continuously growing incisors to remain sharp as they are worn off. Most rodents eat a plant-based diet while some enjoy delicacies such as snails, turtles, clams, crayfish, ants and scorpions. Rodents have a large cecum where bacteria digest cellulose into useable carbohydrates. After this plant material has been processed in the cecum the animal eats it again to use as energy. This behavior is known as coprophagy.