You can find bacteria everywhere. They're invisible to us. I've never seen a bacterium, except under a microscope. They're so small, we don't see them, but they are everywhere.
Think of the earth as a living organism that is being attacked by billions of bacteria whose numbers double every forty years. Either the host dies, or the virus dies, or both die.
From dead plant matter to nematodes to bacteria, never underestimate the cleverness of mushrooms to find new food!
For the first half of geological time our ancestors were bacteria. Most creatures still are bacteria, and each one of our trillions of cells is a colony of bacteria.
We can, for example, be fairly confident that either there will be a world without war or there won't be a world - at least, a world inhabited by creatures other than bacteria and beetles, with some scattering of others.