A network of dry river beds lies beneath the Sahara Desert; one that science has only recently discovered. A team of geologists, sand boarders and adventurers cross the desert to look for clues on how a lush savanna became one of earth's driest places.
The life story of the Grand Canyon, from the moment of its birth, through a painstaking period of growth over several billion years, through to the dramatic events that gouged this massive and breathtaking scar into the earth.
The Great Barrier Reef abounds with life. But it is under attack from above and below the water. A team of marine biologists and geologists investigate the clues of how the reef was born, what makes it thrive and how it may disappear within our lifetime.