Playa del Carmen, a popular vacation destination on Mexico's Yucatán Peninsula, faces significant Sargassum strandings during summer months, as do other Caribbean coastlines. To maintain beach access for swimmers, the brown algae must be regularly cleared using machinery. Researchers at the Max Planck Institute for Chemistry have now been able to use coral drill cores to uncover the mechanism driving these algal blooms. Credit: Arkadij Schell By early June this year, an estimated 38 million