From ABC Science Online, 30 May 2014:
Large coral reefs have acted as survival centres for fish biodiversity during periods of climatic upheaval, explaining the extraordinary biodiversity present in the Indo-Pacific region.
The findings appear in an international study published today in the journal Science.
Researchers used sediment core data to map the changing distribution of coral reefs around the world over the past three million years, examining sea surface temperatures and compared how these correlated with fish biodiversity today.
“The main purpose of this was to examine the role that coral reef habitat has played through time in preserving biodiversity in the marine environment,” says co-author and evolutionary biologist Dr Peter Cowman, formerly of the Australian National University and now Yale University.
Their data suggests that the huge network of coral reefs stretching from the northern coast of Australia up through Indonesia and the Philippines has protected and nurtured fish biodiversity through more than thirty interglacial cycles of major cooling and warming — including rising and falling sea levels — over three million years.
These stable reefs have also helped to reseed the surrounding habitats when the climate returned to more favourable conditions, Cowman says.
This was evident in the fact that the species found in these protected areas have a much older lineage than fish species outside the refugia, reflecting the fact that the protected species were more likely to survive climate upheaval while those outside were less likely. These older lineages were then able to diversify out into the stable, but fragmented habitat. Read more.