Coral reefs off the coast of Abu Dhabi. | John Burt, courtesy of Amin Mohamed As extreme heat destroys more coral reefs, scientists are racing to find new — and sometimes unexpected — ways to keep them alive. Some are trying to encourage corals to reproduce more, while others are testing for heat fitness using picnic coolers. A recent study has a new approach, and it comes from an unexpected place: the corals’ own microbiome. Corals, like humans, have a multitude of bacteria living in and on them. It has long been assumed that this diverse population of microbes serves a role similar...