Is evil peculiar to humans? Or is it a force of nature, a biological reality with its own evolutionary influences, survival value, strange agenda? Such are the questions pondered by Watson (The Dreams of Dragons, 1986; Supernature, not reviewed; etc.) in this fluid, elegant study of what it means to be bad. ""Evil, it seems, may have its own peculiar reasons and seasons. And it would be very useful to know exactly what these are."" Watson tackles the notion of evil from an evolutionary perspective: What are its valid natural reasons for existing? How does it fit into the ecological tendency toward balance and harmony? First, Watson lays some groundwork. His evil is anything that disrupts the integrity of the ecological moment--the sense of place and community--anything that disturbs diversity, relative abundance, and communication. We can understand the cellular response of killing off, en masse, strangers to the realm; we can appreciate infanticide among birds and hyenas when Darwinian survival comes into play. Even the warring of the Yanomami can be seen in terms of population flux. But how does one account for a Bundy or a Dahmer? They may well be, suggests Watson, one of those nasty by-products of the human capacity to defy the genetic imperative, to think too much, giving us poetry and music on one hand, and the Holocaust on the other. Our consciousness may occasion a break with organic and genetic evolution so abrupt that cultural controls are not in place. This is far too modest a sampling of Watson's survey to convey the range and depth of his inquiry, its playings back and forth, the twining of biological, cultural, psychological, and ethological considerations--delicate and intricate as a Persian carpet. A book to be read with deliberateness--sentence by sentence, as in its density it is easy to lose the train of thought--every bit yielding something fascinating to chew on.