A playful and diverting, yet always scientifically rigorous look at those simple mysteries that are yet to be solved Why are so many giraffes gay? Has human evolution stopped? Where did our alphabet come from? Can robots become self-aware? Can lobsters recognize other lobsters by sight? What goes on inside a black hole? Are cell phones bad for us? Why can't we remember anything from our earliest years? Full of the mysteries of life, the universe, and everything, this is a fascinating and unputdownable exploration of the limits of human knowledge of our planet, its history and culture, and the universe beyond.