One-Organism Ecosystem

Deep under the surface of earth, in a gold mine in South Africa, scientists have found an organism that completely lives on its own! It does not depend on any other organism in its environment for food and survival.

In the solid rocks as deep as the height of CN Tower multiplied by 6, there are fractures where water got trapped for millions or probably billions of years. In those waters, there is an organism that lives on hydrogen and eats sulphur. It doesn't need even sunlight to survive.