Oxygen – we all need it, we can't live without it. It's integral to life on this planet. And it's probable that, as you watch this film, you will be breathing in an oxygen atom that was also breathed by Genghis Khan – or by the first ever apes to stand upright on the plains of Africa. The oxygen that we breathe is made from two oxygen atoms joined together – O2. They were first joined more than 3 billion years ago by the earliest blue-green algae to evolve. The oxygen molecule first came from bacteria and was present in the fires that destroyed the dinosaurs and the chemical reactions in all human cells, and as ozone they protect the earth from radiation. Since then, both together and apart, they've had the most extraordinary adventures. Each of the two atoms in an oxygen molecule is virtually indestructible – so they have been first-hand players in some of the most dramatic events in the whole of Earth's history. It's often said that we are breathing the same oxygen that the cavemen did. The life of a single molecule of oxygen is traced on it's astonishing journey spanning millions of years, from its creation, into photosynthesis, through the age of the dinosaurs, early man, and on into today.
Part 3: Survival When David Attenborough first visited the Great Barrier Reef in 1957, he considered it the most spectacular place in the natural world and he assumed that it would last forever. Since then the coral has been dying at an unprecedented rate. In this episode he undertakes his most important mission to understand what the next few decades hold for this remarkable community of animals, as well as what is being done to save it. On his journey, David uncovers the remarkable ways in which scientists are trying to preserve the reef and embarks on an ambitious exploration of his own, the deepest dive ever on the reef. But despite the discoveries now being made by scientists and in the reef's furthest reaches, David fears for the future of this incredibly complex and beautiful ecosystem so vital for the world's oceans.
The vast plains of Addo Elephant National Park stretch more than 600 square miles into South Africa's interior. Embark on a thrilling journey through this unique wilderness sanctuary and meet its most endangered resident: the African elephant.
In this final episode Professor Brian Cox travels to Iceland, where the delicate splendour of a moonbow reveals the colours that paint our world, and he visits a volcano to explain why the sun shines. By exploring how sunlight transforms the plains of the Serengeti, drives the annual migration of humpback whales to the Caribbean and paints the moon red during a lunar eclipse, Brian reveals the colour signature of our life-supporting planet. Finally, at an observatory high in the Swiss Alps, he shows how these colours aren't simply beautiful, but that understanding how they're created is allowing us to search for other Earths far out in the cosmos.
Once life arrived in the Galapagos, it exploded into unique and spectacular forms. David Attenborough investigates the driving forces behind such evolutionary innovations. We learn that life must be able to adapt quickly in these ever-changing volcanic landscapes. It has resulted in species found nowhere else in the world, such as giant whale sharks and marine iguanas that can spit sea-salt from their noses, dandelion seeds that grow into tree-sized plants and spiders that can blend perfectly into the darkness. Adaptation has been the key to survival in these islands so far, but the story of life in the Galapagos doesn’t end here. The catalyst that triggers these explosions of life remains in place.