We can classify animals into three groups according to what they eat. Plant eaters are herbivores, meat eaters are carnivores, and animals that eat both plants and animals are omnivores. What they eat can often clue biologists into another information about it and its native ecosystem.

HERBIVORES

Any animal that eats only plants is an herbivore. Just because they don't eat meat doesn't mean all herbivores are small. Rabbits, snails and butterflies are all good examples of small herbivores, but horses, cows, zebras and elephants are herbivores, too! In Prehistory, many dinosaurs ate only plants and they were giant. Many different types of animals can be herbivores, including mammals, insects, worms, invertebrates and even some birds. 

CARNIVORES

Any animal that eats only meat is a carnivore. Carnivores often have sharper teeth or fangs to help them cut the meat. Most of the time in their habitat, carnivores will eat herbivores, but they may eat omnivores or even other carnivores if they don't have enough food. Some examples of small carnivores are spiders, frogs and bats. Medium-size carnivores can include eagles, snakes and anteaters. Examples of large carnivores are wolves, lions, tigers or crocodiles.

OMNIVORES

Any animal that can eat both plants and animals is an omnivore. People are omnivores, containing with flat and sharp teeth and the ability to digest meat, fruit, and vegetables for food. Bears are another example of omnivores as they eat both berries and meat. Medium-size omnivores include animals like raccoons, pigs and chickens. 

CURIOUS FACT: 

Often, teeth can help us to know to what category an animal belongs to. This isn't always the case, but herbivores more typically have flatter teeth for grinding up vegetation, while carnivores will have sharp teeth for cutting the meat. Many omnivores will have some combination of the two, helping to easier eating and digestion.

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