Africa - home to the greatest wildlife gatherings on Earth. But even in this land of plenty, wildlife faces huge challenges.
North America, a land of change where pioneering animals make the most of surprising opportunities.
Europe, a crowded continent transformed by mankind, where extraordinary animals are found in surprising places.
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.
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.