Mark Roberts has explored some of the remotest parts of the planet. His career has taken him high into the Papua New Guinean rainforest canopy, deep underground inside Venezuelan mountains and even right into the heart of Indonesia's volcanoes. He has been privileged to work with the world's leading natural history filmmakers and is the only member of the BBC's team to have worked on every one of the eight Expeditions series, starting with Amazon Abyss in 2004.

In this lecture, Mr Roberts gives the audience on a behindthescenes view of two recent projects, telling the stories and secrets of the filming process. As the team's sound recordist, he is in the enviable position of being able to take candid photos of the film crew at work, which he shows in this lecture, in addition to video and audio clips from the two series.

The talk begins in Greenland, home to one of the world's most incredible natural phenomena, iceberg calving. Greenland is losing twice as much ice per year as it was 20 years ago. Every summer crystalclear meltwater lakes form on the icesheet, which drain away through a series of channels, eventually disappearing into huge cracks called moulins. Mark Roberts describes his time on the ice with the BBC Frozen Planet team as they attempted to discover why these moulins are so important to understanding the behaviour of the Greenland icesheet.

Then, travelling to the other side of the globe, Mr Roberts tells stories from his experiences in Central and South America, whilst filming the BBC's latest project, The Dark: Nature's Nighttime World. The series explores how animals have adapted to a life in complete darkness. Using the latest lowlight camera technology, the crew and a group of scientists spent over 6 months in some of the most inaccessible parts of the region and made some startling revelations about nocturnal animal behaviour. Spiders with an unconventional use of their webs and a new species of swimming cricket were just to two of the team's discoveries.

Mark Roberts was educated at St Albans, England. He trained for broadcast sound engineering, working on programmes such as Red Dwarf and Alas Smith & Jones, as well as the hectic world of news reporting. In 1993 he travelled to Hong Kong to become a sound recordist, working on documentaries about the upcoming 1997 Handover. A chance encounter with a British cameraman then led to his involvement on his first wildlife film, The Secret Life of Seahorses, which won numerous international awards. Since then he has worked on dozens of awardwinning natural history series including Wild China, Walking With Dinosaurs and Lost Land of the Tiger. In addition to his acclaim as a sound recordist, he has written articles and photographed for numerous magazines.