Asia is the largest and most extreme continent on Earth. The animals here live in the hottest deserts, tallest jungles and highest mountains in the world, but global warming and deforestation threaten many species including the orangutan.

South America - the most species-rich continent on earth. From the volcanoes of the Andes to the world's largest rainforest, animals here must specialise to carve out a niche.

Australia, a land cast adrift at the time of the dinosaurs. Isolated for millions of years, the weird and wonderful animals marooned here are like nowhere else on Earth.

Sir David Attenborough explores the continent of Europe - a crowded continent transformed by mankind. From the rare and elusive wolves to the almost-extinct Iberian lynx, this continent needs protection to ensure a future for its wildlife.

Africa, home to the greatest wildlife gatherings on earth. But even in this land of plenty, wildlife faces huge challenges.