First Author

To understand how biodiversity works in coral reefs, a team of Australian researchers surveyed reefs in different sites, islands and regions. When the team analysed the data, they found that coral-reef biodiversity doesn't follow the patterns predicted by one model, called neutral ecology, which argues that coral species colonize reefs in a random way. Instead, the team's studies show that location and environmental change determine what corals fail or thrive (see page 80). Maria Dornelas, a researcher with the Centre of Excellence for Coral Reef Studies in Townsville, explains the implications.

How did you feel when you saw that neutral ecology might not apply to reefs?

We were surprised by the patterns we found. But finding that neutral theory doesn't match is only the first step. How coral communities differ from the theory's predictions, and what that says about the processes that affect coral reefs, is really important.

What sort of reaction do you anticipate from neutral theory's proponents?

We hope it will stimulate comparisons with more data. It will be interesting to see whether other ecosystems show similar patterns and whether biodiversity theory can be modified to better explain our observations of coral communities.

Why do you think reefs turned out to be more variable than you expected?

We think the variability is due to the way that disturbance affects reefs. Reefs are disrupted by cyclones, coral bleaching, crown-of-thorns starfish, and so on. Such disturbances are patchy and unpredictable, and affect different species differently.

What do your samples say about biodiversity from reef to reef?

Several things seem to affect reef biodiversity. There's a strong regional influence, and nearby reefs are more similar than distant reefs. But nearby reefs also vary a lot. We think this variability is mostly due to different reefs being at different stages of recovery from a disturbance.

What implications do your findings have for biodiversity theories in general?

We believe our results suggest that biodiversity theory should place more emphasis on random environmental fluctuations. Disturbances to coral reefs have increased, as a result of global warming and overfishing, so it's important that we understand the consequences of the frequency, intensity and nature of disturbances to improve management and better protect the world's coral reefs.