Coral reefs give birth to a dazzling number of new species of sea creatures, according to a study that highlights their critical role in marine ecosystems.

Scientists have found that the reefs not only harbour amazing biodiversity, but are actively involved in the generation of new life forms. The study overturns conventional thinking that much of the sea life in coral reefs originated elsewhere.

Wolfgang Kiessling of the Humboldt University of Berlin, who led the study, said: “We found that coral reefs are very active at generating biodiversity in the oceans, and that they export biodiversity to other ecosystems. This was a surprise because many people had assumed that reefs were ecological attracters; that species go there from other places.”

He and colleagues in Germany and the US studied a database of fossil organisms that lived on the sea floor from the Cambrian period, about 500m years ago. They compared the number of new genera that first appeared in coral reefs with those in other shallow-water environments and found the reefs were responsible for about 50% more. The results are published today in the journal Science.

Mr. Kiessling said the study offered extra incentive to protect coral reefs. “If we lose the coral reefs we lose the ability for marine ecosystems to generate new species in the future. Increasing carbon dioxide in the atmosphere damages coral as seas become warmer,” he said.