John Nettles explores the late naturalist Gerald Durrell's legacy as he follows the work of a small group of people trying to save endangered orangutans on Jersey and Sumatra.
Man has explored land, the oceans surface, and large parts of the solar system, and in the 21st century we are just beginning to explore the depths of the Pacific Ocean. We yearn to unravel the mysterious Pacific but she does not give up her secrets willingly.
Fish dominate the planet's waters through their astonishing variety of shape and behaviour. The beautiful weedy sea dragon looks like a creature from a fairytale, and the male protects their eggs by carrying them on his tail for months. The sarcastic fringehead, meanwhile, appears to turn its head inside out when it fights. Slow-motion cameras show the flying fish gliding through the air like a flock of birds and capture the world's fastest swimmer, the sailfish, plucking sardines from a shoal at 70 mph. And the tiny Hawaiian goby undertakes one of nature's most daunting journeys, climbing a massive waterfall to find safe pools for breeding.
Chris investigates how nature's masterminds measure up against human brain power. Looking at a variety of animals, such as ravens, crows, bees and starlings, Chris explores how different animals can use tools, solve complex puzzles, recognise themselves in mirrors and even reason like humans.