Eventually, new forms of photosynthesis evolved in a group of organisms known as cyanobacteria. These forms of photosynthesis could extract more energy by using water and carbon dioxide as their primary raw materials. Prying electrons loose from water molecules was tougher than capturing them from hydrogen sulfide or iron. But if you could do it, you got more energy, and of course in water, you had a much more abundant source of energy. Using the energy captured from sunlight, these sophisticated photosynthesizers zapped water molecules and stripped electrons from their hydrogen atoms. Then
...more
