Plagues of locusts regularly bring destruction and famine to many parts of Africa. Now scientists in Kenya are trying to capture the elusive smell used by locusts to signal to each other whether or not it's time to swarm. Meanwhile in the Arizona desert, the eight inhabitants of Biosphere 11 prepare to leave the enclosed world they have lived in for the past two years. What have they and science learned from the experience? With Howard
Stableford, Kate Bellingham ,
Carmen Pryce and Judith Hann. Producer Jack Weber
Editor Dana Purvis