The bumper book of things that nobody knows

There are many, many things that nobody knows... Do animals have a sense of humour? Why do we have five fingers? What did Jesus do in his youth? Has human evolution stopped? Can robots become self-aware? What goes on inside a black hole? Bringing together The Things That Nobody Knows and Even More Things That Nobody Knows, this bumper volume takes us on a guided tour of 1,001 gaps in our knowledge of cosmology, mathematics, animal behaviour, medical science, music, art and literature.