This week historian Sandra Herbert tells how she retraced Darwin's footsteps to the Galapagos in search of rock samples to prove his volcanic theories were right...

This week we're in conversation with Sir Terry Pratchett, author of the multi-million selling Discworld series. We find out what inspired 'The Science of Discworld 3: Darwin's Watch', get Richard Dawkins into holy orders and explore a world without Darwin...

Darwin's first book was on coral reefs. Brian Rosen, from the Natural History Museum in London,takes up the story...