The primary diet of herbivorous animals consists mainly of plants. These animals have adapted to consume various plant materials, including grasses, leaves, fruits, and vegetables. Their digestive systems are specialized to break down the cellulose in plant cell walls, which is a primary component of plant material. Herbivores play a crucial role in ecosystems as they help in seed dispersal and the maintenance of plant populations. Examples of herbivorous animals include cows, horses, and elephants, each having unique adaptations that support their plant-based diets, such as flat teeth for grinding vegetation.