In his first book, 'Gaia: A New Look at Life on Earth', Jim Lovelock proposed a startling new theory of life: the Earth, its rocks, oceans, atmosphere and all living things, are part of one great organism, evolving over the vast span of geological time. In this sequel, he examines environmental and scientific issues in detail, including the greenhouse effect, acid rain, the depletion of the ozone layer, and the destruction of tropical forests.