Bears, deer and wolves are examples of omnivores, herbivores and carnivores respectively. Many animals that are considered carnivores, such as foxes, actually eat plants as well. Not only do red foxes eat fruit, but they sometimes eat carrion.
Bears are largely omnivorous. Both grizzly bears and black bears eat nuts and berries as well as fish. However, panda bears are strictly herbivorous. Ants are an unusual example of omnivores. They eat seeds but feed on insects as well if given the opportunity.
Herbivores are either grazers or browsers, which means they graze on grass and small plants on or near the ground or browse on leaves and twigs from larger plants. Elephants do both, while giraffes are especially adapted to browsing in treetops with their long necks. Deer are an example of herbivores and are an important source of food for carnivores like wolves and lions.
Carnivores include dogs and cats. In fact, carnivores evolved millions of years ago roughly into two groups: the ancestors of cats and the ancestors of dogs. Throughout time, the cat-like carnivore group evolved into mongooses, cats and hyenas. The dog-like group evolved into dogs, seals, raccoons, badgers and wolverines. Among this group, raccoons and bears are considered omnivores.