David Attenborough takes a breathtaking journey through the vast and diverse continent of Africa as it has never been seen before. (Part 4: Cape) Southern Africa is a riot of life and colour because of two great ocean currents that sweep around the continent's Cape. To the east, the warm Agulhas current generates clouds that roll inland to the wettest place in southern Africa. To the west is the cold Benguela current, home to more great white sharks than anywhere else. Moisture laden fog rolls inland, supporting an incredible desert garden. Where the two currents meet, the clash of warm and cold water creates one of the world's most fabulous natural spectacles - South Africa's sardine run. This is the greatest gathering of predators on the planet, including Africa's largest, the Bryde's whale.
Professor Brian Cox follows Earth's epic journey through space. He takes to the air in a top-secret fighter jet to race the spin of the planet and reverse the passage of the day. In Brazil, a monstrous wave that surges up the Amazon River provides an epic ride of a different kind - chased by a top surfer through the rainforest, this tidal wave marks Earth's constant dance with the Moon. Greenland experiences some of the biggest swings in seasons in the world, but despite the deep freeze, the harsh winter brings opportunity to the Inuit people who live there. All this spectacle here on Earth signals that we are thundering through the universe at breakneck speed. Brian explains why we can't feel it and how understanding motion brings us to understanding the nature of space and time itself, leading to the astonishing conclusion that the past, present and future all exist right now.
This programme focuses on birds. The feather is key to everything that is crucial about a bird: it is both its aerofoil and its insulator. The earliest feathers were found on a fossilised Archaeopteryx skeleton in Bavaria. However, it had claws on its wings and there is only one species alive today that does so: the hoatzin, whose chicks possess them for about a week or so. Nevertheless, it serves to illustrate the probable movement of its ancestor. It may have taken to the trees to avoid predators, and over time, its bony, reptilian tail was replaced by feathers and its heavy jaw evolved into a keratin beak.
It is an unexpected and contrasting journey through America's iconic and varied landscapes as the Mississippi flows from source to mouth. The Mississippi's greatest surprise is its incredible reach. Its fingers stretch into nearly half of the USA, collecting water from 31 states. More than any other, this one river has helped unite the many and varied parts of America.