Does anything eat wasps?

Every year, readers send in thousands of questions to New Scientist, the world's best-selling science weekly, in the hope that the answers to them will be given in the 'Last Word' column - regularly voted the most popular section of the magazine. Does Anything Eat Wasps? is a collection of the best that have appeared, including: Why can't we eat green potatoes? Why do airliners suddenly plummet? Does a compass work in space? Why do all the local dogs howl at emergency sirens? How can a tree grow out of a chimney stack? Why do bruises go through a range of colours? Why is the sea blue inside caves? Many seemingly simple questions are actually very complex to answer. And some that seem difficult have a very simple explanation. New Scientist's 'Last Word' celebrates all questions - the trivial, the idiosyncratic, the baffling and the strange. This selection of the best is popular science at its most entertaining and enlightening.