Three billion year ago, our planet was not yet the blue planet. Lava from the gigantic eruptions of thousands of volcanoes poured into an enormous ocean, which was already inhabited by millions of primitive bacteria. They would be the victims of the first ecological disaster on earth. A highly toxic element called oxygen began to filter into the water. The bacteria, unable to tolerate the presence of this new element, died.
The disaster that struck these primitive bacteria was due to a revolutionary new function for light: photosynthesis. Through sunlight, molecules of carbon dioxide decomposed, liberating the residual oxygen. The primitive bacteria were incapable of surviving in this radically changed environment, and the numbers of the new photosynthetic bacteria rose inexorably. Over a period of thousands of years, oxygen transformed the biosphere of the earth, gradually transforming the colors and chemistry of the environment initiating the journey in the development of life forms leading to the present day.