Final answer:
A keystone species has significant impact on its ecosystem, often influencing the diversity and abundance of other species. Examples include the intertidal sea star and the banded tetra, with disruptions to these species leading to significant ecological consequences. Their study is crucial for understanding ecosystem dynamics.
Step-by-step explanation:
A keystone species is an organism that plays a critical role in maintaining the structure of an ecological community, affecting many other organisms within the ecosystem and thus, determining the types and numbers of various other species in the community. A classic example of a keystone species is the intertidal sea star, Pisaster ochraceus, found in the northwestern United States. The removal of this predator leads to an overabundance of its prey, mussels, which in turn alters species composition and reduces biodiversity. Similarly, the banded tetra is a keystone species in tropical streams because of its role in the cycling of phosphorus, a vital nutrient, within its ecosystem.
These examples illustrate that keystone species are critical for ecosystem balance and biodiversity.Loss of a keystone species can lead to dramatic changes in ecosystem composition and reduce biodiversity, which may have cascading effects throughout the ecological community. Therefore, understanding the role and impact of keystone species is essential for wildlife ecologists, community ecologists, and those involved in species conservation and ecosystem management.