by Sumedha Rav­is­hankar and Ian Rob­bins — Mi­crobes fa­cil­i­tate un­told bi­o­log­i­cal processes, from di­ges­tion in the tiny gut of an in­sect to run­ning our planet's bio­geo­chem­i­cal cy­cles. These mi­cro­scopic be­ings truly are the quiet pup­peteers of our lives. And it makes sense that they would be, since uni­cel­lu­lar life has been on Earth for about 3.5 bil­lion years...