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on the 14th of September.

Until then, each week we're offering an episode from our archive of nearly 1,000 programs,

which I hope you'll enjoy.

Have a good summer.

Hello, whenever shipwrecked sailors find sanctuary on a desert island under a coconut palm,

they can thank coral.

These tiny undersea creatures once dead, leave behind stony skeletons, and more corals

grow on those until they form a mountain.

They speak above the water, the sailor on that peak.

Meanwhile, the submerged corals, sometimes called the Rain Forests of the Oceans, team

with life, or in the case of many, did team until killed by rising water acidity and temperatures

and the great storms that come with climate change.

When we discuss coral are Nicola Foster, lecturer in marine biology at the University of

Plymouth, Gareth Williams, associate professor in marine biology at Bangalore University School

of Ocean Sciences, and Steve Jones, senior research fellow in genetics at University College

London.

Steve Jones, what did Charles Darwin notice from the Beagle when looking at coral islands?

I think it was a very important moment to him, because nobody had before had really understood

how a coral island could spring out from a deep ocean, because corals need the light

to grow.

...