Ants are tidy—when they move into a new nest box, they spend the first days cleaning it thoroughly, just like humans moving into a new home. Many ants produce highly acidic chemicals from specialized glands in their body. Researchers have assumed that ants only spray this poison, which is made mostly of formic acid, to fight other ants and would-be predators. But in two studies published in 2013 and 2018, Sylvia Cremer and her team showed that ants use acidic chemicals to disinfect nest mates contaminated and infected with pathogens.