Why are marine microorganisms so important?

The ocean is filled with microorganisms. Billions of years ago these tiny little creatures gave us the oxygen we breathe today by taking huge proportions of carbon dioxide out of the air, converting it to oxygen and as a result shaping the climate of the whole planet to its current state! They are essential to the health of our environment, and hence the survival of humankind. Yet, our knowledge of this hidden majority is only fragmentary. What is a relatively simple task for zoologists and botanists - identifying species and finding out what they do - is exceedingly complex for microbiologists who study life that is invisible to the human eye.

To be included: graphics from Miriam and infographic text