Rebecca Stott says the idea of 'going down a rabbit hole' is often characterised as a bad thing - here, she makes the case for what's to be gained. "These days we invariably use the phrase 'down the rabbit hole' to describe a negative experience...where people get lost, then become overwhelmed, ensnare themselves in conspiracy theories and can't get back out," she says. "But I don't believe rabbit holes are bad in themselves. If we avoid them altogether we lose the chance to experience their joy and excitement." She recalls her own experience of discovery - and tells the story of how Charles Darwin once spent eight years distracted by barnacles. Producer: Sheila Cook Sound: Peter Bosher Production coordinator: Liam Morrey Editor: Richard Fenton-Smith