Ants

The 100 trillion ants in the world weigh as much as all the people on earth and have colonised the planet like no other animal.

Chris Packham explores the ingenious ways in which ants have collaborated to achieve their global success - natural air-conditioning systems keep ants cool in their nests, shelters made from their own bodies protect nomadic ants from the elements and a sense of smell five times more powerful than other insects allows them to overpower animals hundreds of times larger than themselves.

Remarkably, new research reveals how ant colonies are capable of immunising themselves against diseases.