In it, an apparently normal-looking petri dish is treated so as to reveal a message when wetted with water vapor. The contrast between hydrophobic and hydrophilic surfaces, which is not visible to ...

The team filled small petri dishes with polyurethane, a common plastic most frequently used in medical and industrial products, and measured whether and how fast the fungi could consume it.

Petri dish A glass or plastic circular dish. Used in combination with agar to grow cells. Quadrat A square grid, often 1m squared. Used to sample plants or slow moving animals e.g. snails.