Although it is true that nearly every organism on earth depends, in one way or another, on the sun for energy, this is not true for all life.

Photosynthesis plays a key role in nearly all ecosystems on earth, with plants using up light energy from the sun to create simple sugars as food source.

The plants themselves essentially form the bottom of nearly every food web on earth, and thus all the energy is derived from the sun.

Yet, down in the depths of earth’s oceans, where no sunlight ever penetrates, the ocean bed is also teaming with life.

There are no photosynthetic organisms there, as there is no light source that can provide the driving force for photosynthesis.

Rather, chemosynthesis is the driving force for all life in these vast depths. Hydrothermal vents at the bottom of oceans, for example, provide a rich source of chemicals that can be used by such organisms to produce energy.

These organisms have never seen the light of day, literally, and yet they thrive happily on chemosynthetic processes. The discovery of these organisms has opened our horizons even further to possible locations in which life on other planets might proliferate successfully.