"My dear, let us hope that it isn't true!" the wife of the bishop of Worcester is reputed to have exclaimed 150 years ago, on hearing that human beings might be descended from apes. "But if it is true, let us hope that it doesn't become widely known!" When it comes to sociobiology - better known these days as "evolutionary psychology" - the bishop's wife has modern counterparts: The religious right and the secular and supposedly scientific left are remarkably on the same page, both sides inclined to dispute or misrepresent the relevance of evolution to human beings. The former,...