As the Kalahari Desert faces a worsening dry season, prides, packs and herds of all kinds must rely on the power of family to survive.

From BBC Earth Films, the studio that brought you Earth, comes the sequel - Earth: One Amazing Day, an astonishing journey revealing the awesome power of the natural world. Over the course of one single day, we track the sun from the highest mountains to the remotest islands to exotic jungles. Breakthroughs in filmmaking technology bring you up close with a cast of unforgettable characters. Told with humour, intimacy and a jaw-dropping sense of cinematic splendour, Earth: One Amazing Day highlights how every day is filled with more wonders than you can possibly imagine- until now.

Fifty years ago there were close to half-a-million lions in Africa. Today there are around 20,000. To make matters worse, lions, unlike elephants, which are far more numerous, have virtually no protection under government mandate or through international accords. This is the jumping-off point for a disturbing, well-researched and beautifully made cri de coeur from husband and wife team Dereck and Beverly Joubert, award-winning filmmakers from Botswana who have been Explorers-in-Residence at National Geographic for more than four years. Pointing to poaching as a primary threat while noting the lion's pride of place on the list for eco-tourists-an industry that brings in 200 billion dollars per year worldwide-the Jouberts build a solid case for both the moral duty we have to protect lions (as well as other threatened big cats, tigers among them) and the economic sense such protection would make. And when one takes into account the fact that big cats are at the very top of the food chain-and that their elimination would wreak havoc on all species below them, causing a complete ecosystem collapse-the need takes on a supreme urgency.