Which phrase describes a keystone species?
A. The species that uses the most resources in an area
B. A species that is crucial to the health of a community
C. A species that preys on all the other species in a community
D. The first species to colonize an area
The Correct Answer and Explanation is :
The correct answer is B. A species that is crucial to the health of a community.
A keystone species is defined as a species that plays a critical role in maintaining the structure of an ecological community. Its presence and activities have a disproportionately large impact on the environment and other species within that community. The concept of keystone species was introduced by ecologist Robert Paine in the 1960s, who demonstrated that certain species can influence the types and numbers of various other species in an ecosystem.
Keystone species can take various forms, such as predators, herbivores, or even plants. For example, sea otters are considered a keystone species in kelp forest ecosystems. By preying on sea urchins, which are herbivores that graze on kelp, sea otters help maintain the balance of the ecosystem. If sea otters are removed, sea urchin populations can explode, leading to overgrazing of kelp and subsequent degradation of the entire ecosystem. This illustrates how a single species can have a significant influence on the overall health and stability of an environment.
Other examples of keystone species include wolves in Yellowstone National Park, which help regulate elk populations, and bees, which play a crucial role in pollinating many plants. The loss of a keystone species can lead to dramatic shifts in the ecosystem, often resulting in decreased biodiversity and altered habitat structure.
In summary, keystone species are vital to the health of their ecosystems, and their roles must be understood and protected to maintain ecological balance and biodiversity.