Herbivores have teeth that are highly specialized for eating plants. Because plant matter is often difficult to break down, the molars of herbivores are wider and flatter, designed to grind food, and aid in digestion. Herbivore incisors are sharp for tearing plants, but they may not be present on both the upper and lower jaw. White tail deer are a perfect example of an herbivore that has only lower incisors and a rigid upper jaw that assists in the tearing of plants. Many animals, such as horses and cows, have jaws that are capable of moving sideways. Elephants are herbivores, and their incisors are unlike those found in other animals. Odd as it may sound, a tusk is actually a tooth, an incisor, that has evolved into a different type of tool, often used for defense.
Carnivores have a set of teeth that are very different from herbivores. That makes sense, because they also have a different diet. A carnivore will use its teeth to kill a prey item before eating it. The sharp incisors and pointed canine teeth are perfectly designed for both incapacitating and eating a meal. A canine tooth can be easily identified, as it is the longer, pointed tooth located on either side of the incisors. The molars are fewer in number than other animals may have, mainly because so much of the work is done by the teeth in the front of the mouth. While the presence of canine teeth does not guarantee that an animal is a carnivore, it is an indicator that meat is some part of the diet.