Grasslands cover one quarter of all land and support the vast gatherings of wildlife, but to survive here animals must endure the most hostile seasonal changes on the planet. From Asia's bizarre-looking Saiga antelope to the giant anteaters of Brazil, grassland animals have adapted in extraordinary ways to cope with these extremes. In the flooded Okavango, lions take on formidable buffalo in epic battles, on the savannah bee-eaters take advantage of elephants to help catch insects and, on the freezing northern tundra, caribou embark on great migrations shadowed by hungry Arctic wolves.

A jaguar fights to keep his river home in Brazil as the night brings both challenges and opportunities to hunt. Evening is falling in the world's greatest tropical wetland, Brazil's Pantanal. A stronghold for South America's most secretive big cat, the jaguar. And enjoying the last warmth of the day is a male known as Juru. At six years old and weighing over 100 kilos, he's amongst the largest, most powerful big cats in the Americas. This prime stretch of river has been his territory for two years. But tonight Juru's reign hangs in the balance. In a recent fight with a rival male, he badly injured his paw. It's left him weak and hungry. The coming days and nights will test him more than ever before. He'll need to summon the strength to defend his river.

Privately, he was humble, almost shy, and fiercely patriotic, donating millions to his native Brazil and contemplating a life beyond motor-racing. Yet he is struck down in his prime on the blackest weekend in the history of the sport, watched live on television by 300 million people. Years on he is revered in Formula One as the greatest motor racing driver of all time - and in Brazil as a Saint.

The story of the monumental life and tragic death of legendary Brazilian motor-racing Champion, Ayrton Senna. Spanning the decade from his arrival in Formula One in the mid 80's, the film follows Senna's struggles both on track against his nemesis, French World Champion Alain Prost, and off it, against the politics which infest the sport. Sublime, spiritual yet, on occasion, ruthless - Senna conquers and transcends Formula One to become a global superstar.

There is a contest each year that can change a young skater's life. There are no pros with million dollar endorsement deals here, just real kids with real lives and everything on the line. This is the story of a few of the best, from France, Brazil and the USA, as they risk everything for a chance of a lifetime. Motivation 3: The Next Generation is a proper follow-up to The Motivation but this time the stakes are so much higher. We're in deep with real kids escaping poverty and violence, crashing in skate-houses or still living with mom. For all of these kids a win at Tampa Am could mean a way out and an opportunity to do what they love for a living-skate.

On the coast, two worlds collide. Coasts are the most dynamic and challenging habitats in the ocean - that brings great rewards but also great danger. The extraordinary animals that live here must find ingenious ways to cope with two very different worlds. This episode is a rollercoaster ride of heart-stopping action and epic drama, peopled with characters from the beautiful to the bizarre. We meet fish that live on dry land and puffins that must travel 60 miles or more for a single meal, and witness a life-and-death struggle in a technicolour rock pool. In a secluded cove in the Galapagos, sea lions feast on 60kg tuna. It should be impossible - tuna are usually far too fast for sea lions to catch. But here the sea lions club together to herd their prey inshore. Once trapped in the shallows, these huge fish are easy pickings. As the tide recedes in Brazil, lightfoot crabs leap from rock to rock, desperately avoiding the water - their lives depend on it. Moray eels launch themselves from rock pools, jaw gaping. Then octopuses, too. Both crawl across dry rock to set their ambush. Elsewhere, the ever-changing tides create rock pools. But these temporary worlds are a battleground. Predatory starfish turn a magical garden into the stuff of nightmares.