A visit to arguably the most famous archipelago on Earth, the Galapagos. It's home to a myriad of bizarre and unique creatures, endemic to these islands - but how did they get here and what is the key to these extraordinary islands that allows them to thrive? The programme reveals that this key holds not just the secret to life here, but also to how Darwin was able to leave with the ideas that would revolutionise biology.

Painted over five centuries ago, Filippo Lippi's nativity is like none other: it shows the birth of Christ in a dark, wooded wilderness. There are no shepherds, kings, ox, ass – there is no Joseph. Its beauty inspired Michelangelo, Leonardo da Vinci and Botticelli. But it also conceals a deeply personal story. It was painted for Cosimo de Medici, a wealthy banker who feared that his money was dragging him straight to hell. The artist's life was equally surprising. One of the most celebrated painters of his day, Filippo Lippi was also a Carmelite friar, but he was no stranger to the temptations of the flesh, to which he frequently yielded. Shortly before painting his Adoration, he caused uproar by seducing a twenty year-old nun. His paintings rejoice not only in divine beauty, but in the beauty of women. In later times, the Adoration's history was interwoven with that of rulers and dictators. It became a bargaining chip after Napoleon's allies seized twenty merchant ships. And in the 20th century, it was hidden by the Nazis in a potassium mine, where specialist american officers, known as Monuments Men, stumbled upon it. they were now told to get it ready to be shipped out. In an unprecedented turn of events they refused. This is the only known case in the whole of the Second World War of American officers refusing an order. It was sent to the National Gallery of Art, but in 1949 Lippi's Adoration was returned to Germany.