The first of these is Mary Roach's new book about the human digestive system, Gulp. It is generally entertaining rather than enlightening, a decent addition to her previous work on sex and space. Indeed, the latter of those two had quite a lot to say about zero-gravity poo; Gulp has even more to say about poo, in more familiar circumstances. But she starts further up the alimentary canal, with explorations of taste and nutrition. There is perhaps a little more than I would have wanted to read about competitive eating and empirical tests of stomach capacity in living humans. As ever, she manages to make the scientists researching this vital issue come alive, with asides about, for instance, whether live oysters are conscious of being eaten (probably not). I am also now much better informed about the fine muscle control of the teeth and jaw at one end (think of the microsecond decisions that must be made when crunching popcorn) and the anus at the other.
I happened to be on an intercontinental plane flight suffering from a minor gastric upset as I read this, and it did take my mind off my discomfort by encouraging me to consider the bigger picture. Recommended for anyone with a sufficiently strong stomach.