Feeding is the process by which organisms, typically animals, obtain food. Terminology often uses either the suffixes -vore, -vory, or -phage, -phagy, -phagous.
A carnivore is an animal which eats only meat. Predators commonly hunt their own prey. Scavengers are carnivores which eat animals they did not hunt themselves. Carnivores which eat mainly or only insects are called insectivores. Carnivores which eat mainly or only fish are called piscivores.
A herbivore is an animal that only eat plants. They are herbivorous animals. Herbivores (such as deer, elephants, horses) have teeth that are adapted to grind vegetable tissue. Many animals that eat fruit and leaves sometimes eat other parts of plants, for example roots and seeds. Usually, such animals cannot digest meat. Some animals are frugivores because they eat mainly fruit. Browsers eat mostly leaves and sometimes small tree branches. Animals that eat mostly grass are grazing animals.
An omnivore is an animal whose species gets its energy and nutrients from a diet made up foods that include plants, animals, algae, fungi and fruits. Many omnivores change their eating habits during their life cycle. Omnivores come from diverse backgrounds that often independently evolved sophisticated consumption capabilities. For instance, dogs evolved from primarily carnivorous organisms, while pigs evolved from primarily herbivorous organisms. Despite this, physical characteristics such as tooth morphology may be reliable indicators of diet in mammals, with such morphological adaptation having been observed in bears.
Hematophagy is the habit of certain animals to feed on blood. Since blood is a fluid tissue rich in nutritious proteins and lipids that can be taken without great effort, hematophagy is a preferred form of feeding for many small animals, such as worms and arthropods. Examples of animals that feed on blood are mosquitoes, vampire bats and leeches.