David Attenborough looks at the problem of finding food, and the ingenious ways animals have of getting through the lean season, discovering that it is a devious business requiring exploitation and even theft. While plants try to defend themselves from unwelcome visitors, animals have devised numerous ways to break down the defences.

A tiny ant makes marathon journeys over the scorching desert. An albatross flies 800 miles over open ocean before returning with food for its chick. Hundreds of lobsters march in columns over the seabed to avoid storms. All find their way with an accuracy that we have only recently achieved.