Being at the top of the food chain is not always an advantage, as illustrated by the microscopic "extremophiles" in the hot volcanic springs of Yellowstone; among other survivors of the Great Dying are blue-blooded horseshoe crabs and jellyfish.

Get a fascinating look at the way of life of proboscis monkeys, which survive by choosing not to fight in the fiercely competitive world of nature.

The blue-lined sea bream appear out of nowhere in the thousands, perform a wild flash dance, and disappear in a flash; a Japanese researcher studies this mysterious behaviour.

RATED 14+. Bear Grylls takes on Big Sky Country, paragliding above the Rockies, traversing vast gullies, and making the most of abandoned debris before making his great escape on a moving train.

Journey through time to discover how the Mediterranean gave birth to ancient empires, the earliest agriculture, and three of the world's great religions.