Coral stress 'like never in history'

Large scale coral die-offs are now occurring more frequently than at any time in the last 11 000 years, according to a new study by Australian-based scientists. Investigations by Associate Professor John Pandolfi, of the ARC Centre of Excellence in Coral Reef Studies and the University of Queensland, of fossilized reefs in Papua New Guinea show how often the reefs were "wiped out" by disastrous events in past times.