Ecology
Keystone Species
A species that has a disproportionately large effect on its ecosystem relative to its abundance. Removing a keystone species causes dramatic changes to ecosystem structure and function.
Biological Context
Sea otters are keystone predators—they control sea urchins, preventing urchins from overgrazing kelp forests. Beavers are keystone ecosystem engineers—their dams create wetland habitats. Identifying keystone species is crucial for conservation because their loss triggers cascading effects.
Business Application
In business, keystone organizations have outsized influence: TSMC in semiconductors, Visa in payments, AWS in cloud. Their removal would collapse entire industries.