Every year, the American Society for Microbiology holds an unusual art competition. Contestants don’t use paint, pencils, or clay to create the artworks they enter. Instead, they use tiny, single-celled microorganisms, like yeast and bacteria.
The artists start with plates of agar, a jelly-like substance full of nutrients on which microbes can grow. Then they use brushes and other tools to transfer solutions containing microbes onto the plates. The microbe species applied to the plates naturally produce colored substances called pigments or have modified DNA—the material that carries hereditary information—to make pigments.
Artists have to wait until the microscopic organisms have had time to multiply and form colonies large enough to see. Then “the invisible strokes you made become vibrant and visible,” says Tarah Rhoda, who participated in last year’s contest.