THE MICROBES LIVING on Earth are so plentiful as to be innumerable. Untold. Countless. Not in the hyperbolic sense, but the literal, gobsmacking sense. "It's estimated there are 100 million times as many bacteria as there are stars in the universe," says microbiologist Rob Knight, director of UC San Diego's Microbiome Center for Innovation. "And we know almost nothing about most of them."

https://www.wired.com/story/the-crazy-ambitious-effort-to-catalogue-every-microbe-on-earth/