Answer – Examples of keystone species include gray wolves in the Greater Yellowstone ecosystem, elephants in the African savannas, beavers in river ecosystems, and mangrove trees in coastal ecosystems.

Explanation: 

As the name suggests, a keystone species is an organism that ties an entire ecosystem together. The absence of such a species may cause an ecosystem to either be drastically different or cease to exist. The ecosystem is then likely to become home to the most invasive species.

A keystone species is not necessarily one that is the largest in size or present in great numbers; it is, however, one that impacts food webs extensively. It can be a plant, animal, microbe, or any other living being.

Below are a few keystone species examples:

1. Gray wolves in the Greater Yellowstone ecosystem: These predators keep elk numbers in check, preventing the herbivores from overbrowsing on aspen and willow trees. The leftovers from the wolves’ feed also provides easy food access to scavengers like bears and vultures.

2. Elephants in the African savannas: These herbivores feed on small trees and shrubs in the region, keeping the grasslands from turning into woodlands. The grasses serve as food for other grazing animals like zebras and antelopes, allowing them to thrive. Carnivores like lions further sustain themselves by feeding on the grazing animals.

3. Beavers in river ecosystems: Beavers bring down old/dead trees while building dams along riverbanks. The dams allow riverwater to be diverted to the neighboring regions, leading to wetland formation. The wetlands further serve as a rich ecosystem for abundant plant and animal species.

4. Mangrove trees in coastal ecosystems: These trees strengthen the shorelines and reduce erosion by capturing sediments and building soil. The regions where their roots grow through the water function as a safe space for small fish to feed. Mangrove trees are also known as “the kidneys of the coast” as they filter water for offshore corals and seagrasses near the shore.

Other keystone species examples include sea otters, starfish, bees, prairie dogs, and sharks.

Popular Questions