There are many animals in the world’s tropical rain forests that qualify as herbivores. In the broadest sense -- one in which biologists consider organisms like insects to be animals -- there are multitudes of small herbivorous creatures in the rain forest. Caterpillars, for example, are herbivores. When we think of animals, though, we are more likely thinking of what biologists call megafauna, the larger animals. There are plenty of these, too, and several provide good examples of the group at large.
The capybara is a large South American rodent that occurs in the tropical rain forests of the Amazon. It is semi-aquatic, meaning that it is adapted to life in rivers, lakes and pond habitats but does not spend all of its time in the water. Capybaras are herbivores and feed on a variety of plant materials, including grasses, reeds and even bark. They are selective and change their food preferences according to the seasons. One curious, if repulsive fact, is that capybaras, like rabbits, practice coprophagy. This means that they ingest their own feces. Coprophagy is an adaptation that allows animals like rabbits and capaybaras to gain the maximum nourishment from their food, since it passes through the digective tract twice.
The Asian elephant, a smaller but close relative of the African elephant, is an herbivore whose range and habitat includes tropical rain forests. It ranges from Indonesia through Malaysia and Thailand into India. Asian elephants, like their African counterparts, eat prodigious amounts of vegetation to sustain their large bodies. The Asian elephant’s ears are smaller that those of the African elephant, and the Asian only has one “finger” at the end of its trunk while the African elephant has two. Those so-called fingers allow the elephants to grasp small food items.
Gorillas are large primates native to the tropical rain forests of equatorial Africa. They are almost completely herbivores, with invertebrates like insects making up an infinitesimal part of their diets. Gorillas eat leaves, shoots, stems, roots and bark. The mountain gorilla, as its name suggests, is a species that ranges into higher elevations, and the lowland gorilla occupies the tropical rain forests of the lower slopes and other lowlands in tropical Africa.
The okapi is a fairly obscure mammal whose appearance is reminiscent of a zebra, but it is actually more closely related to the giraffe. It is an herbivore and is native to the rain forests in Africa. Okapis use their long, dexterous tongues to pull the leaves off of plants in the rain forest. It doesn’t take long to begin to see the resemblance to the giraffe, both in appearance and behavior, when observing the okapi.