The individual being Prochlorococcus Marinus is probably the most number of organism on Earth – and yet the cyanobacterium should largely only be known by name. This may also be due to its small size: the blue core, which thrives in the top layers of water on the oceans, only has a diameter of about 0.5 to a micrometer, which corresponds to about a hundredth of the diameter of a human hair.
