Elephants are not the most dominant species in African grasslands, yet they influence community structure. The grasslands contain scattered woody plants, but they are kept in check by the uprooting activities of the elephants. Take away the elephants, and the grasslands convert to forests or to shrublands. The newly growing forests support fewer species than the previous grasslands. Which of the following describes why elephants are the keystone species in this scenario?
A) Essentially all of the other species depend on the presence of the elephants to maintain the community.
B) Grazing animals depend upon the elephants to convert forests to grassland.
C) Elephants prevent drought in African grasslands.
D) Elephants are the biggest herbivore in this community.
E) Elephants help other populations survive by keeping out many of the large African predators.

Question

Quizplus · Accepted Answer

A keystone species is one whose presence is critical to the maintenance of the entire community structure. In this scenario, the presence of elephants is essential to prevent the grasslands from converting to forests or shrublands, which would have detrimental effects on the species diversity of the community. Therefore, without elephants, the entire community would be dramatically altered, and essentially all of the other species depend on their presence to maintain the community.

Elephants Are Not the Most Dominant Species in African Grasslands