When E. coli cells aren’t hanging out in a crowd, the rate at which their genes mutate to resist the antibiotic rifampicin increases up to threefold. The finding shows that the microbes’ ability to develop antibiotic resistance depends on a gene that helps the bacterial cells communicate. Manipulating this type of crosstalk among bacterial cells may provide a way to slow the pervasive emergence of antibiotic resistance, researchers suggest April 29 in Nature Communications.