Robert “Bob” Paine’s work with starfish along the coast of Washington state led to understanding of the significance of the ecological impact of a single species. He was regarded as one of the most ...

New research is causing the original keystone species, the ochre sea star Pisaster ochraceus, to lose some of its supposed ecosystem-controlling powers. Photo by Jeff Rotman/Alamy Stock Photo This ...

A keystone in an arch's crown secures the other stones in place. Keystone species play the same role in many ecological communities by maintaining the structure and integrity of the community. The ...