<DIV>Scientists have long believed that a ?great leap forward” some 40,000 to 50,000 years ago in Europe marked the end of significant biological evolution in humans. But top scholars Gregory Cochran and Henry Harpending argue otherwise: not only has the human species undergone a storm of genetic change after civilization arose, human evolution has in fact <i>accelerated</i>, and these ongoing changes have played a pivotal role in history.</DIV>