The natural world is full of colours. For us, they are a source of beauty, but for animals they are a tool for survival. David Attenborough reveals the extraordinary ways in which animals use colour: to win a mate, to fight off rivals and to warn enemies. In India, peacocks dazzle females with magnificent tail feathers; a tiny hummingbird in the deserts of North America unfurls his spectacular headdress as he dances for a mate; and in the darkness of a rainforest, powerful mandrill baboons signal their status with red and blue face masks, while tiny frogs warn of deadly poisons with brilliant colours.