The Creature That Gave Up Parasitism for … Wait, What?

In the late 19th century, when scientists first discovered the single-celled creature called Nephromyces, they thought it was a parasitic fungus. They were wrong. Instead, it’s … well … how to even describe it? It’s a reformed parasite. It’s a creature of extremes, surviving in a world of acids and dining on, of all things, kidney stones. And perhaps strangest of all, it’s an organism that cannot survive as an individual. A single ant will do badly away from its colony; a single Nephromyces wouldn’t even get that far.

can be found all along the eastern coast of the U.S., living inside the bodies of translucent, blobby animals called sea squirts. Some sea squirts look like beautiful, known as sea grapes, look more like cysts that have grown bunny ears.