Another book of lists, this one a good-natured compilation of the life expectancies of things living and otherwise. Much attention is given to human life expectancy--the medical, sociological, and cultural factors affecting it; how to calculate one's approximation to the norm; what life-style changes to make to improve one's chances. Discussing other animal life, the authors are meticulous in pointing out the differences between life spans in the wild and in captivity: although lions live longer in zoos, cheetahs fade away early, after about six years. Domestic animals may be hardier--goats ""knock about for 15 to 20 years, despite diets that include anything from woolen clothing to tin cans."" Along with a section on natural life--snowflakes, moonbeams, flowers, trees--there is some whimsy: ""Imaginary Beings"" includes dwarfs (""selfish and greedy hoarders of treasure"" who live about 200 years), hobbits, and sirens. There's even some practical advice on foods--how to store them and for how long. Much of this is arbitrary (the life span of a well-maintained kitchen knife), some is intriguing (Albania has the highest rate of births by women over 50), and anyone who is serious about any of it should go where the authors got their information (the McGraw-Hill Encyclopedia of Science and Technology, the Columbia Encyclopedia, The CBS World Almanac, etc.). But for a half-hour or so of mental doodling, it's just fine.