Last century, earthquakes killed over one million, and it is predicted that this century might see ten times as many deaths. Yet when an earthquake strikes, it always takes people by surprise. So why hasn't science worked out how to predict when and where the next big quake is going to happen? This is the story of the men and women who chase earthquakes and try to understand this mysterious force of nature. Journeying to China's Sichuan Province, which still lies devastated by the earthquake that struck in May 2008, as well as the notorious San Andreas Fault in California, Horizon asks why science has so far fallen short of answering this fundamental question.
The picturesque Lake Constance region is characterized by intensive agriculture - with dramatic results for the bird life. Since 2003, the ornithologist Professor Peter Berthold has been creating new habitats for birds - alongside cultivated landscapes.
Professor Iain Stewart uncovers clues hidden within the New York skyline, the anatomy of American alligators and inside Bolivian silver mines, to reconstruct how North and South America were created. We call these two continents the New World, and in a geological sense they are indeed new worlds, torn from the heart of an ancient supercontinent - the Old World of Pangaea.
The air around us is not just empty space; it is an integral part of the chemistry of life. Plants are made from carbon dioxide, nitrogen nourishes the soil and oxygen gives us the energy we need to keep our hearts pumping and our brains alive. But how did we come to understand what air is made of? How did we come to know that this invisible stuff around us contains anything at all?