SYDNEY, Aug 24 (NNN-XINHUA) – Marine scientists saw a ray of hope for the world’s endangered coral reef systems, which are under an ever-increasing threat, due to rising ocean temperatures.
An international team, led by researchers from Southern Cross University’s National Marine Science Centre (NMSC), in the Australian state of New South Wales (NSW), has found that, coral populations have the genetic potential to adapt to their warming environment.
NMSC researcher, Dr. Emily Howells, said, scientists already knew that coral could have an exceptionally high heat tolerance, but in this new study, published in Science Advances, “We wanted to test whether we could transfer these beneficial genetic variants to a comparatively heat sensitive coral population, living in milder oceanic conditions.”
To do this, researchers cross-bred corals from the thermally extreme Persian Gulf, with those of the same species from the milder Indian Ocean and then measured the performance of many families of their offspring.
They found that heat tolerance increased by up to 84 percent, when Indian Ocean mothers were bred with Persian Gulf fathers and was, on average, equivalent to the heat tolerance of offspring, with both parents from the Persian Gulf.
“This was an impressive result, because, while we were expecting to see some enhancement of heat tolerance, the signal was much stronger than we anticipated,” Howells said.
The researchers took the offspring to the Indian Ocean site and found that cross-bred corals with Persian Gulf fathers survived equally, as well as, native Indian Ocean purebred corals.
These results demonstrate that corals can be selectively bred for enhanced heat tolerance, using corals from populations in extreme or warmer environments, which have a higher proportion of heat-tolerant genetic variants.
“Selective breeding has the potential to be used to enhance the resilience of targeted coral populations to climate warming, but requires further testing before it can be implemented in intervention and restoration programmes,” Howells said. “However, the most important actions to enhance the resilience of all coral populations are those that limit the magnitude of climate change.”
“Now on the Great Barrier Reef, we are undertaking in-depth assessments of the physiological and genetic variation that exists within and among breeding populations.”
Preservation of coral has become an increasingly important field of study in Australia, as the nation is the custodian of the Great Barrier Reef, which in recent years, has suffered a series of bleaching events, where the vibrant colors are drained away, leaving behind skeletal-looking reef formations.– NNN-XINHUA
