It’s long been a theory of mine that corals exchange zooxanthellae within our aquariums to combat environmental stressors, and a new study proves this theory to be true in controlled systems as well as in the wild. The University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science led the study, which simulated ocean-acidification in controlled tank environments. “Since ‘symbiont shuffling’ occurs in only some cases, we wanted to understand what drives this process and whether it could help corals adjust to climate change,” said Ross Cunning, lead author of the study. Researchers then allowed these specimens to recover in different temperatures to gauge which clades of zooxanthellae they adopted, and with a firm theory here, Cunning suggests temperature could be a controlling factor when it comes how and what symbionts are exchanged: “We discovered that partner switching in Caribbean star corals is dependent upon the severity of the bleaching event and the temperature during recovery.” Two similar studies were also conducted in the Coral Reef Futures lab at UM. “Together, these studies suggest that that the rate of warming, timing between bleaching events, and severity of each bleaching event, will play an important role in determining coral survivorship. We need to better understand these changes in order to accurately predict coral reef futures.” adds Andrew Baker, UM Rosenstiel School associate professor of marine biology and ecology at UM.