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Australia's Great Barrier Reef may be able to survive warming sea temperatures that result from global warming better than first thought, Australian scientists say, because some algae tolerate heat better than others.

Coral geneticists from the Australian Institute of Marine Science have found that many corals store several types of algae, which can improve their capacity to cope with warmer water.

"This work shatters the popular view that only a small percentage of corals have the potential to respond to warmer conditions by shuffling live-in algal partners," institute marine scientist Madeleine van Oppen said.

"Simply, when conditions warm the more heat-tolerant algae provide back-up, become more abundant. Some algal types impart greater resistance to environmental extremes," Dr. van Oppen said in a statement received on Friday.

Since the 1980s, reefs around the world have been devastated by coral bleaching, when temperature increases of even 1 degree Celsius can cause the coral to expel the photosynthetic algae that keep them supplied with nutrients.

Numerous scientific studies have warned that global warming of the ocean was threatening the very existence of reefs, such as the Great Barrier Reef.

The Australian scientists said their study had found that coral has the ability to "shuffle" the algae, maximizing nutrients depending on water temperature. They discovered heat-resistant algae by examining the DNA of different types of coral.

Many marine scientists have argued, however, that "back-up" algae were infrequent because of the small number of corals that were shown to host several types of algae.

"The potential for this hidden back-up type (algae) to step in and provide nutrition to coral during heat stress is far greater than currently thought," said Jos Mieog, a PhD student involved in the coral study.

The Australian scientists said this "shuffle" ability might explain why coral reefs have been able to survive for thousands of years during various climate changes.

"This flexibility discovered in our research is important in understanding the past evolutionary success of these coral species and their future survival capacity in the face of a changing climate," said Dr. van Oppen.