The significance of keystone species lies in their critical role in maintaining the structure of ecological communities. These species have a disproportionately large impact on their environment relative to their abundance. They influence the population dynamics of other species and help regulate ecosystem functions. For example, predator keystone species can control herbivore populations, preventing overgrazing and supporting plant diversity. The removal of a keystone species can lead to dramatic changes in community composition and ecosystem stability. Recognizing and protecting keystone species is vital for conservation efforts and ecosystem management.