A look at one of the most famous habitats on the planet, the Serengeti in East Africa, a vast grassland that is home to some of the greatest concentrations of herbivores on the continent. But what is the key to this exceptional grassland that allows such density and diversity?

Steve Backshall lifts the lid on an incredible world of intricate relationships and unexpected hardship in the Amazon rainforest, explores the way that the jungle's inhabitants interact, and reveals a hidden secret that might just be what keeps the whole place alive.