At one extreme of size is the a tiny planktonic marine copepod called Oithona, which is only a few hundredths of a milimetre long.....

.....while at the other extreme, the African elephant is the largest of all herbivores.

Herbivores which eat seeds are called granivores, while those which eat fruits are termed frugivores, and both may be important to plants as agents of seed dispersal. These groups include many birds, such as the Knysna lourie, the grey lourie,the Ramaroon pigeon, and the starlings. Many small mammals, and even some insects are also important seed dispersers.

Other herbivores which are important in land communities include small mammals, such as the African scrub hare....

.... and larger mammals, such as the North American white-tailed deer.

Seed eaters such as the African giant rat are also herbivores of some consequence.

There are a multitude of herbivorous insects, some of which are herbivorous as larvae.

Omnivores, such as the Chacma baboon, are are important consumers of plant material, and also play a role as agents of seed dispersal....

.... as the large number of seeds in this pile of baboon dung indicates.

Turning to the seashore, we find that molluscs (distant relatives of the garden snail) are generally the most important herbivores in the intertidal zone, while below the low tide mark the spiny sea urchins are formidable grazers. In warmer waters, especially on tropical reefs, fishes are major consumers of plant material.

Important groups of marine herbivores include the molluscs, such as the South African limpet, Patella longicosta,which guards a garden of the crustose brown seaweed Ralfsia.

Sea urchins, such as the South African Parechinus angulosus, can be very significant grazers in tide pools and below the reach of the tides.

Herbivorous fishes, such as the surgeon fishes, reach their greatest abundance and diversity in the tropics (Powder Blue Surgeon, Sodwana Bay).