Herbivores

Herbivores are animals that obtain most of their energy and nutrients by consuming plants. They practice a wide range of feeding styles, including grazing on grasses, browsing on leaves and shoots, and consuming seeds, fruits, or nectar. As primary consumers, they transfer plant energy to higher trophic levels and influence vegetation structure and dynamics.

Many herbivores are specialized for particular plant parts. Grazers feed mainly on grasses; browsers target leaves, twigs, and fruits of woody plants; granivores subsist on seeds; frugivores on fruits; nectarivores on nectar. Digestive adaptations vary: ruminants such as cattle, sheep, and many deer species have multi-chambered stomachs that harbor microbial fermentation; nonruminant herbivores such as horses and some primates rely on hindgut fermentation. Herbivores also show a suite of dentition suited to processing fibrous plant matter, including sharp incisors and broad flat molars for grinding.

Plants have evolved defenses such as toxins, tough cell walls, and spines, while herbivores develop detoxification capabilities, specialized mouthparts, and microbial partners to extract nutrients. Herbivory shapes plant communities and can drive coevolution with plant defenses. Some herbivores, especially fruit eaters and seed eaters, aid in seed dispersal, while others reduce vegetation density and alter competitive relationships among plant species.

Humans interact with herbivores through agriculture, livestock production, and pest management. Domesticated herbivores such as cattle, sheep, goats, horses, and camels provide food, labor, fiber, and companionship, while wild herbivores influence ecosystems and conservation priorities. Understanding herbivory helps explain energy flow in ecosystems and the evolution of plant defenses.