A new study by scientists Ross Cunning and Andrew Baker at the University of Miami shows that corals may be more severely impacted by climate warming when they contain too many symbiotic algae. The single-celled algae living inside corals are usually the key to coral success, providing the energy needed to build massive reef frameworks. However, when temperatures become too warm, these algae are expelled from corals during episodes of coral 'bleaching' that can lead to widespread death of corals. Until now, it was thought that corals with more algal symbionts would be more tolerant of bleaching because they had 'more symbionts to lose.' The new findings, published in Nature Climate Change shows that the more symbiotic algae a coral had, the more severely it bleached, showing that too much of a good thing can actually be bad.