collaborating on both this series and the forthcoming Frozen Planet. Filming The first year of production was spent researching possible stories for the series. The Life team contacted scientists and experts around the world in search of new discoveries to film, and new approaches to familiar subjects. Nearly three years of filming followed, involving 150 shoots on all seven continents, many of them full-scale expeditions to remote wilderness areas. New camera technology was used to build on the cinematic techniques first employed in Planet Earth, notably the pioneering use of stabilised helicopter-mounted cameras. The Life crew succeeded in using gyroscopic stabilisation to create steady shots from moving vehicles, even on rough terrain, allowing the cameras to track alongside reindeer and elephant herds for the first time. Miniature high-definition cameras were used extensively for the "Insects" programme. In the forests of Mexico, the crew erected a spider's web of cables in the canopy to give the sense of flying alongside millions of monarch butterflies. In Zambia, they filmed from a hot air balloon to avoid disturbing the huge flocks of straw-coloured fruit bats. Following recent debate about the use of artifice in natural history programmes, the BBC were more candid about sequences which had not been filmed in the wild. Close-ups of wild clownfish would have disturbed their natural behaviour, so captive animals were filmed in an aquarium at a Welsh university. Despite the best efforts of the film-makers, some sequences ended up on the cutting room floor. Scientists in Arctic Scandinavia had accumulated enough evidence to suggest that golden eagles were the main predators of reindeer calves, but an attack had never been witnessed. After two summers tracking the herds in Finland, cameraman Barrie Britton finally filmed a hunt in full. However, the attack had taken place nearly a mile away, and the footage was too distant to be considered for broadcast. Television firsts The budget and timescale for the series enabled the producers to set ambitious filming challenges, and expedition crews brought back several sequences which have never been shown before. Some involved highly specialised hunting behaviour that has only recently been discovered. In the shallow, muddy waters of Florida Bay, one pod of bottlenose dolphins have learned a unique hunting technique called mud-ring feeding. Aerial photography shows the lead dolphin circling a shoal of mullet, flicking its tail flukes to disturb mud on the seabed. The fish trapped