You're listening to the London Review of Books podcast. I'm Thomas Jones. I'm joined today by Liam Shaw, a postdoctoral fellow at the McLean Lab in Oxford, researching bacterial genetics.

But he has a piece in the latest issue of the LRB on Coral Reefs. It's a review of Life on the Rocks by

Julie Berwald. Hello, Liam, and thank you very much for talking to me. Nice to be here.

So I suppose to begin with the basics, although it's not actually that basic, is it? And that

what is coral, animal, vegetable or mineral, or a mix of all of the above?

Yes, it's a great question.

And I mean, that's something which early thinkers on coral struggled with a lot.

So it sort of looks plant-like, but is mineral in the sense that it's kind of rocky.

If you take it out of the sea and keep it in a cabinet of curiosities, it's mineral in that sense.

But now we understand that coral is within the animal kingdom.

So although it has this plant-like appearance,

it's in fact formed of colonies of many, many tiny animals of the same sort.

And this is the taxonomic classification of coral.

They now sit within the anthozoa, which means flower animals.

And the anthozoa is a broader taxonomic classification

that includes things other than corals, so things like anemones, which are sort of single

things called polyps, which is basically an animal that has these stinging tentacles that come out of it.

So in corals that we're talking about, the corals that build coral reefs,

many of these polyps come together and form a colony,

and they assemble a skeleton of calcium carbonate around them,

and that solidifies and forms the kind of hardness of the

coral that we see in the reefs. But there are other sorts of coral as well, such as soft corals

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