"With attention to detail, Stephen Jay Gould first describes the content and discusses the history and origins of the three core commitments of classical Darwinism: that natural selection works on organisms, not genes or species; that it is almost exclusively the mechanism of adaptive evolutionary change; and that these changes are incremental, not drastic. Next, he examines the three critiques that currently challenge this classic Darwinian edifice: that selection operates on multiple levels, from the gene to the group; that evolution proceeds by a variety of mechanisms, not just natural selection; and that causes operating at broader scales, including catastrophes, have figured prominently in the course of evolution. Then, in a stunning tour de force that will likely stimulate discussion and debate for decades, Gould proposes his own system for integrating these classical commitments and contemporary critiques into a new structure of evolutionary thought. ". "In 2001 the Library of Congress named Stephen Jay Gould one of America's eighty-three Living Legends - people who embody the "quintessentially American ideal of individual creativity, conviction, dedication, and exuberance. " Each of these qualities finds full expression in this peerless work, the likes of which the scientific world has not seen - and may not see again - for well over a century. "--BOOK JACKET.