Animal adapted to subsist solely on plant tissues. Herbivores range from insects (e.g., aphids) to large mammals (e.g., elephants), but the term is most often applied to ungulates. Adaptations for a herbivorous diet include the four-chambered stomach of ruminants, the ever-growing incisor teeth of rodents, and the specialized grinding molars of cattle, sheep, and goats. Certain herbivores eat only one type of food (e.g., the koala), but most have at least moderate variety in their diet.
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