Scientists are cautiously optimistic about signs of resilience emerging in some corals despite adverse conditions.
According to the US National Oceanic and Atmospheric Administration global warming caused by climate change is creating hostile ocean environments that are killing or 'bleaching' corals.
This is bad because corals are seen as the foundation of marine ecosystems much like trees are to forests.
The coordinator of the administration's Coral Reef Watch, Mark Eakin, says studies on the Great Barrier Reef in Australia showed those corals that survived a major bleaching event in 2016 also lived through a second bleaching event in 2017.
Mr Eakin told Koroi Hawkins that while this is good news it doesn't necessarily mean corals are evolving.