A brief look at two indigenous populations of the Amazon, and their relations with the Brazilian society and the wider world. The book is a substantially revised edition of Unnatural Selection: The Yanomami, the Kayapó, and the Onslaught of Civilization, originally published in 1998, and includes a new chapter examining the controversy following Patrick Tierney's book Darkness in El Dorado.  (AMZ107, $18.95)