National Geographic News, Reporting Your World Daily

Sunday, November 22, 2009

Photo: Hurricanes Heal Reefs in Surprising Cases


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These time-lapse photos of corals in Florida—from pre-bleaching (a) to recovery (d)—shows corals can heal themselves if exposed to cooler ocean temperatures, which often follow hurricane activity.

Corals depend on a type of symbiotic algae, zooxanthellae, to survive. As the oceans warm, many of the corals "bleach" as the temperature-sensitive algae flee the hard corals' skeletons.

Photographs courtesy PNAS