Some Corals can Cope with Rising Temperatures, Stanford Researchers Find

Stanford researchers have found that corals are adapting to rising ocean temperatures.

Coral reefs provide food and shelter to several marine organisms, which is why they are sometimes called as the "rainforests of the ocean. The reefs are made by certain algae and coral polyps. The coral reefs harbor nearly 25 percent of marine life, despite accounting for just one percent of the entire ocean floor.

Rising global temperatures are threatening the existence of these corals. The new study by Steve Palumbi at Stanford University and colleagues has shown that corals can live in hot waters. The adjustment to rising temperature through internal function in some species is as much as 50 times faster than adaption due to evolutionary changes alone.

"The temperature of coral reefs is variable, so it stands to reason that corals should have some capacity to respond to different heat levels," said Palumbi, director of Stanford's Hopkins Marine Station and a senior fellow at the Stanford Woods Institute for the Environment. "Our study shows they can, and it may help them in the future as the ocean warms."

For the study, researchers at Palumbi's lab removed some corals from a warm pool to a cold pool and vice versa.

Researchers found that over time, corals from the cold waters adapted to living in hot water. These corals were only half as heat-tolerant as corals living in hot pools throughout the study. However, the study shows that corals could adapt to rising temperatures using internal control mechanism.

"These results tell us that both nature and nurture play a role in deciding how heat-tolerant a coral colony is," Palumbi said in a news release. "Nurture, the effect of environment, can change heat tolerance much more quickly - within the lifetime of one coral rather than over many generations."

The study shows that the corals might be able to cope with slight variation in temperature. However, climate change is also associated with a rise in oceanic acidity, which the organisms might not be able to tolerate, researchers said.

The study is published in the journal Science. Palumbi's work was supported by The Stanford Woods Institute.