Fresh hope for the survival of threatened coral reefs has emerged with the publication of a breakthrough paper co–authored by a faculty member at King Abdullah University of Science and Technology (KAUST).

Marine Science Assistant Professor Christian R. Voolstra worked with other researchers from the US and Germany to examine differences in the response to heat stress in the same species at two locations — off the coast of Mexico and in the waters around Florida.

They found the first evidence of local adaptation in coral resulting from differing conditions at separate sites — and their work supports the theory that coral may be able to adapt to deal with the effects of global warming.

This in turn could pave the way for the preservation of coral that is dying out in a particular area because of deteriorating conditions. This would be achieved by importing the same species from other areas (a so–called different ecotype) where, through natural selection, it had successfully adapted to similar conditions.

"What we found is that basically you have better adapted variants of a coral species in response to surface temperature in some places than in others," said Dr Voolstra. "The site causes the genes to be different – the same species can be different depending on where it comes from."

"Coral cover is declining worldwide, this is the situation we have to deal with. Studies prove corals are severely stressed and this is connected to high sea surface temperatures, which in turn are linked to higher carbon dioxide levels in the atmosphere."

"We looked into the response of the same coral species at different locations and what we found were indications that you have local adaptation in coral species. It is a nugget of hope — a way out of the misery for coral species."

"Usually when people look at coral they pick their species, they pick their location and they look at that species in that location. What we show in this study is that if you take the same coral species in different locations the response to temperature might be different."

"What it means for conservation management and for the future is that if you want to save a coral species you should look at the global distribution and check how the coral behaves in different locations."

The team had to determine whether their findings were the result of simple acclimatization or full-blown adaptation. "Acclimitization is a response to an environment but is not genetically fixed, whereas we have indications that there is a genetic difference so it is heritable and stays that way if you transfer coral."

"The waters off Mexico are warmer than around Florida if you compare the annual mean temperature and summer maxima and we see corals from Mexico behaving better in higher temperature. So the idea is that you would take corals from Mexico and export them to the Florida Keys for example."

The natural next step for the team would be to conduct research here on KAUST’s doorstep, in the Red Sea.

"In the Red Sea we find large temperature variability, we find very high temperatures, we find very high salinity. There must be some local specialization or adaptation in coral species and this is why I think it’s very worthwhile to do research in the Red Sea. It’s very under–researched and it’s like a huge test tube as there is very little exchange due to the small opening."

The paper — Location-specific Responses to Thermal Stress in Larvae of the Reef–building Coral Montastraea faveolata — has been published on the PLoS ONE online journal of peer–reviewed research.