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 tomorrow in the journal Science.
The team looked at fossils of so-called benthic organisms, such as starfish, clams and corals that live on the seabed. They ignored fossils of fish, which do not offer clues to where they evolve, because after they die their remains can float elsewhere.
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. I suspect that new species evolve every single day, but unfortunately not as fast as they go extinct.”
Increasing carbon dioxide in the atmosphere damages coral as seas become warmer, which causes the coral to bleach, and become more acidic, which makes it hard for the tiny animals to repair their exoskeletons.
Experts say the world has already passed the safe level of carbon dioxide in the atmosphere for coral reefs, and even the most ambitious carbon cuts planned for coming decades will fail to save them