At first sight, penguins seem ill-suited to their environment - rotund abdomens, stubby little legs and stiff wings appear to make the going tough. But in fact it is these very traits that enable this bird to thrive.Chris explores details of the penguin's anatomy, using new scientific research to reveal how its legs, wings and body shape have allowed it to conquer an extraordinary range of habitats, from deep forests to tropical waters, bustling cities and even the toughest place on the planet - Antarctica.

Bears can live in practically every habitat on Earth, from tropical jungles to the Arctic Ocean. Wherever they are found, they are capable of surviving extreme conditions and extracting the highest-quality food.Detailing the latest research, Chris Packham explores the specialised adaptations that have enabled bears to thrive, including how a polar bear's hollow fur allows it to feed throughout the gruelling Arctic winter, whilst a state of 'walking hibernation' sees it through the summer months.

Chris Packham delves beneath the skin of the big cats to explore what makes them such good hunters, and he reveals that it is not all about brawn.New scientific research shows how subtle adaptations in their anatomy and physiology contribute to the success of all stages of a big cat hunt: the stalk, the capture and the kill.Leg hairs help the leopard to stalk and intricate muscle fibres drive the snow leopard to capture its prey. For the jaguar, jaw muscles and whiskers combine to give it a precision bite that can take down a caiman, and an enlarged area of the lioness's brain gives it the edge over all their big cat cousins.