They have been blown up in nuclear tests and poisoned when people fished with cyanide. However, the absolute biggest threat to the future of coral...
Text: Sofia Eriksson/TT
Photo: Claudio Bresciani/TT, Jim Maragos/AP/TT, Andrew Ibarra/NOAA/TT, David Wood/TT, Adam Ihse/TT
Graphics: Anders Humlebo/TT