Gardening grandmother Ruth Brooks, also known as 'the snail lady', was chosen as the BBC's Amateur Scientist of the Year in 2010. She noticed that despite repeatedly throwing her snails over the garden fence, her gastropods would return home to decimate her petunias. From her Radio 4 experiments, designed by mentor Dr Dave Hodgson, from the University of Exeter, they showed that snails do have a homing instinct, returning from distances of over 10 metres.

In this documentary, Ruth sets out to investigate how different animals navigate, from smell maps for cats to astronomy for dung beetles. She travels to Portsmouth to meet some speedy pigeons and visits an MRI laboratory where neuroscientists are hunting for the source of their mysterious magnetic sense.

But do we humans have a homing instinct, and can we improve our sense of direction?