The different nutritional requirements of the zebra, wildebeest, and Thomson's gazelle determine their food preferences. Instead of competing for vegetation, they facilitate the grazing of the ones which follow.
The zebra's non-ruminant digestive system allows for quick processing of food, enabling it to consume larger quantities than the wildebeest and Thomson's gazelle. Thus, it can tolerate a poorer quality of grass and meet its nutritional requirements by consuming more. Additionally, the upper and lower razor-sharp teeth of the zebra are adapted for chopping the poorer quality stems and stalky portions of grass leaving the more nutritious leaves.
Digestion takes nearly twice as long for the [G 41 / ruminant] wildebeest; therefore, it must consume higher quality grass to compensate. It grazes on the more nutritious short grass and leaves left after the zebra has cleared away the dry tops and stems. The wildebeest's broad muzzle, large lips and [I 012 / dental structure] are well adapted for mowing short grass.
The Thomson's gazelle, a small ruminant, is more restricted in its grazing than the larger wildebeest. Because of its size, it is greatly limited in the amount of food it can digest at one time; thus, it requires the highest quality grass. The wildebeest's grazing action stimulates new shoots to sprout and exposes the high-protein [G 12 / dicotyledons]. The more pointed muzzles of the Thomson's gazelles are specially adapted for clipping these nutritious portions unavailable to the wider muzzled grazers.
Other herbivores, depending on the area of the ecosystem, are part of the grazing succession as well, although in far fewer numbers. Elephants, [I 002 / buffalo] and [P 002 / hippos eat large, coarse grasses]. The warthog grazes on very short grass like the Thomson's gazelle but supplements its diet with roots and seeds and the [I 010 / kongoni] eats dry stalks avoided by other herbivores.
