Delving into the dark depths of science this week is Ron Douglas who describes the fascinating world of deep sea fish, bioluminescence and the sights from a deep sea sub, Jason Hall-Spencer talks about cold water corals and the threats posed by fishermen, and in slightly warmer waters David Kline reveals how Caribbean corals are suffering due to sugar pollution. Also in the show, Fran Beckerleg interviews John Ablett about a giant squid called Archie, and getting the low down on the high seas Derek finds out how a submarine works in Kitchen Science. Like this podcast? Please help us by supporting the Naked Scientists