Humankind, it turns out, is a rather fragile species, demanding temperate climates, limited atmospheric pressures, and an environment relatively free of acidity, alkalinity, and toxicity in order to survive and reproduce. Microbes are far less picky about their surroundings and, as John Postgate explains in The Outer Reaches of Life, have managed to adapt to virtually every ecological niche that our planet offers. Extremes of heat, pressure, acidity, or alkalinity are no barrier to microbial life. There are microbes that feast on sulfur, iron, nitrogen, and hydrogen--even oils, plastics, and fluoroacetate, a potent pesticide. Postgate adeptly illustrates the variety of the microbial world and explains (in a jargon-free fashion) what scientists understand of its functioning. But perhaps the strongest feature of this book is its ability to convey the intense challenges facing microbe researches who strive to unlock the secrets of microscopic life and its amazing adaptations.