Some herbivores, like a beaver, have large incisors or front teeth that help with gnawing. Omnivores, such as boars and humans, have a combination of both pointed and flat teeth to match their varied diet. The shape of a mammal's jaw can also provide clues to its diet. Herbivores tend to have thick, square lower jaws that help with grinding and crushing tough plant material. The lower jaw of a carnivore is slender and works with the upper teeth like a pair of scissors, slicing and cutting the meat of its prey.
Humans are omnivores.
Our teeth have a combination of carnivore and herbivore characteristics. Our lower jaw is square shaped to help us with the grinding of the plant material that we eat. As you eat your next meal, concentrate on which teeth you rely on to eat certain foods. Although humans are not predators, our eyes face forward and help us judge distances, much like other primates judge distances in the trees.