We might slice them into a salad, savor them in a sauce, wonder at their power to intoxicate or poison, marvel at their multifarious presence in the forest--but few of us realize that mushrooms, humbly thriving on decay, are crucial to life on Earth as we know it. In this book a distinguished biologist, long intrigued by the secret life of fungi, reveals the power of these curious organisms--not quite animal, not quite plant--to enchant and instruct, to nourish and make way for all sorts of superior forms of nature.

In a style at once learned and quirky, personal and...