To maximize longevity, you might think it’s best to play it safe and stay cozy. But some scientists believe we should do the opposite, as exposure to extreme temperatures can trigger our bodies’ own defenses against the killer diseases of old age. Chris heads for the freezing Arctic with his brothers Liam and Luke to take on the ultimate cold therapy.

From a primate that’s no bigger than a mouse, to a chameleon that can fit on your fingertip, the natural world is full of fantastically small animals. Biologist Patrick Aryee explores the fascinating secrets behind these miniature marvels and shows that they’re not the underdogs you might think they are. Super Small Animals follows him as he meets the leading experts on these pint sized superstars, and finds out what makes them some of the most successful on the planet.
First up, he reveals the huge benefits that being small can bring. There’s the little lemur whose diminutive frame helps it to exploit a unique gap in the eco-system, the tiny hummingbird that uses its size to out-maneuver the competition, and the world’s smallest seahorse that never has to leave home. He also explores why small animals are proportionally the strongest in the world, and introduces a peanut-sized beetle that can pull over a thousand times its own weight.
Next he explores the challenges that animals face when they shrink in size, and the ingenious ways they overcome them. We find out how the smallest armadillo in the world manages to control its temperature in the searing desert sun, and the how the world’s smallest fish can survive in nothing more than a puddle, because it never really grows up. Patrick meets a secretive hippo that lives in the dense jungle, and looks like it’s been shrunk in the wash, and some of the world’s smallest snakes that give birth to enormous babies. He also meets a scientist that studies how really tiny spiders have a surprising trick that enables them to travel an incredible 40 miles per day, using almost no energy.
Then there are the animals that refuse to be pigeon holed as small, and manage to punch way above their weight. He puts some astonishing invertebrates to the test, to see how they work together to become much bigger than the sum of their parts and meets a pint-sized predator that takes on some of the largest and most dangerous creatures on the planet, getting hands on to discover how its build helps it to be brave. Finally he uncovers the incredible lengths that deep sea anglerfish go to in order to be big and small at the same time, and has an endearing encounter with a tiny carnivore that manages to be small in just one direction.
Whether their size helps them to hunt, hide or survive, all these remarkable animals prove that good things really do come in small packages.

Physicist Dr Helen Czerski journeys to the extremes of the temperature scale, where the everyday laws of physics break down and a new world of scientific possibilities begins. In the first part, Frozen Solid, Helen reveals how cold has shaped the world around us and why frozen doesn't mean what you think it does. She meets scientists pushing temperature to the limits of cold, driving technologies such as superconductors.
The second part, A Temperature for Life, explores the narrow band of temperature that has led to life on Earth, how life began where hot meets cold and how every living creature depends on temperature for survival. In the last part, Playing with Fire, Helen Czerski explores the science of heat. She reveals how heat is the hidden energy contained within matter with the power to transform it from state to state.

The Namib Desert is one of the oldest deserts and also one of the most diverse. With 50ºC (120ºF) temperatures and half a millimetre of rainfall annually, we see how this is possible. Half the size of Oklahoma, from its Skeleton Coast through the sea of sand to the haze of distant mountains this apparently forbidding desert hides secret water sources.

Are rising temperatures driving Earth's ecosystems past a point of no return? We have promising technologies that put solutions within our grasp. Scientists are exploring solutions: from geoengineering to sucking carbon out of the air to cloud brightening, as means to cool the planet. Cutting-edge solutions and high-risk measures. But would they work? And what are the risks of engineering Earth's climate?

Episode 3 continues to show the obstacles faced with charging electric bikes in remote places, but Ewan McGregor and Charley Boorman start to learn and evolve their process. The risk of cold temperatures is high but they bravely do it anyway. The duo is having a hard time of it out there but, thankfully, the scenery is absolutely stunning. Heading through Patagonia, Ewan and Charley stay at an eco-lodge in one of the world’s remotest areas with people that live off the grid.