The Last Word, edited by Mick O'Hare (Oxford, £7.99 in UK)

This collection of questions and answers from the popular column which features on the last page of New Scientist magazine every week will come as a godsend to anyone who has ever wondered why the sky is blue, why men have nipples or why superglue doesn't stick to the inside of the tube. And if you think the question are ingenious, wait till you see the answers - usually more than one per question - which are sent in by readers from all corners of the earth, some experts in their field, some just exceptionally well-informed smart alecks. Oh, all right, just to put you out of your misery: because of a phenomenon known as Rayleigh scattering (which is also, by a strange quirk of physics, the reason why sunsets are red), because male and female embryos are identical at the early stages of development, and because superglue needs water as well as oxygen to do its thing, in that order. But if you want to know why birds don't fall out of trees when they sleep, you'll just have to buy the book, right?