Diatoms are among the most important organisms in the world that you probably never think about. Scientists estimate that up to half of the Earth’s oxygen in our atmosphere is produced by diatoms, which are abundant in fresh and salt waters of the world. Yes, you can thank the trees and other land plants for some of the oxygen we breathe, but it is really diatoms and other tiny aquatic photosynthesizers that do most of the work. Diatoms are single-celled algae (aquatic photosynthetic orga ...