Microbes seem to be overshadowed by larger forms of life, probably because they are so small, but they are still by far the most abundant life form on the planet, constituting some twenty-five times the total biomass of all animal life. There are well over a million different types, mostly harmless environmental microbes. They are in the air we breathe, the water we drink and the food we eat—and when they die they set about deconstructing us. Each ton of soil contains more than 10,000,000,000,000,000, microbes, many of which are employed in breaking down organic material to generate essential nitrates for plants to utilize; every year nitrogen-fixing bacteria recycle 140 million tons of atmospheric nitrogen back into the soil. (1)
