If you’re small, smells are a good way to stand out. A team of researchers led by the Netherlands Institute of Ecology (NIOO-KNAW) has demonstrated for the first time that two different types of micro-organisms—bacteria and fungi—use fragrances, known as terpenes, to hold conversations. And that’s not all: “We actually believe that terpenes are the most popular chemical medium on our planet to communicate through,” they report.