'Engine' of the coral reef discovered; farmed algae 'like an alien'

From the Web site of Underwater Times:

Queensland, Australia (Aug 29, 2007 18:19 EST) A team of coral researchers has taken a major stride towards revealing the workings of the mysterious ‘engine’ that drives Australia’s Great Barrier Reef, and corals the world over.

The science has critical importance in understanding why coral reefs bleach and die, how they respond to climate change – and how that might affect humanity, they say.

Scientists at the ARC Centre of Excellence for Coral Reef Studies, James Cook University and the University of Queensland have compiled the world’s first detailed gene expression library for Symbiodinium, the microscopic algae that feed the corals – and so provide the primary energy source for the entire Reef.

“Symbiodinium uses sunlight to convert CO2 into carbohydrates for the corals to feed on. At the same time there’s evidence the corals control its output, suggesting that they are farming their captive plants” Professor David Yellowlees explains.

“But these microscopic algae are quite weird and unlike any other lifeform. They have different photosynthetic machinery from all other light harvesting organisms. They have 100 times more DNA than we do and we have no idea why such a small organism needs so much. They really are like no other living creature we know.

This is echoed by team member Prof Ove Hoegh-Guldberg who comments it is ‘like no other organism on planet’, jokingly labeling it “like an alien”.

This strange beast not only rules the fate of the world’s coral reefs – it also plays a significant role in soaking up carbon dioxide from the atmosphere, turning it into nourishment for the corals and powering calcification. Its decline would not only kill the reefs but accelerate CO2 buildup.