I’ve been reading that biologists have determined that certain predators are key to preserving diversity in various eco systems: starfish, for example, serve the function by consuming mussels that would otherwise destroy the diversity in tide pools and fresh water largemouth bass are a keystone species in freshwater streams controlling the populations of minnows that would otherwise over-graze plant life. In the waters off western Alaska sea otters control the populations of sea urchins that can devastate kelp forests.

The lesson to be learned, I guess, is that keystone species are necessary to control populations of system threatening species in order to maintain healthy diverse eco-systems. I wonder whether a keystone species might exist somewhere that could control the species most responsible for threatening the health of the earth.