NPR reports that oceanographers have found a new life-form that can survive on chemicals alone at the bottom of the Pacific Ocean. 

http://www.npr.org/2011/12/05/142678239/the-deep-sea-find-that-changed-biology?sc=fb&cc=fp

These life-forms are worms (Riftia pachyptilla). They have no digestive system and feed by using their red tuft to absorb the hydrogen sulfide coming from vents at the bottom of the ocean.

They can get up to 7 feet long and are anchored to the ground by their white tubular bodies.

This discovery is so remarkable because it causes us to question our current theories of how life first evolved on earth. The worms do not need light in order to survive, but utilize a completely different source of energy.