From Scientific American, a cover story on the migration history of humans: DNA study traces human origins across the continents (and more and more). Here's the full text of The Bounds of Reason: Game Theory for the the Behavioral Sciences and the full text of A Cooperative Species: Human Reciprocity and its Evolution, by Herbert Gintis. Are Democrats and Republicans finally agreeing on a new economic philosophy? 61 flip-flops and counting: Here's a list of clear 180-degree switches by John McCain on the biggest issues of the day. French philosopher BHL supports Obama; post-Jesse Jackson bump goes flat. Britain's bestsellers are under fire, but are they any worse than their American counterparts? Here come the muhajababes! How sex, booze and heavy metal fit into the world of hip young Arabs today. The web is the most conservative force on Earth: Charles Leadbeater on how digital technology has made us a society of mass archivers.  The internet and its enemies: A chorus of Cassandras claim that the internet is ruining our brains; Christian Lorentzen clicks through the evidence. A review of The Future of the Internet by Jonathan Zittrain. From Discover, an article on the world's largest dump: The Great Pacific Garbage Patch. From Dance, dance is, by its very nature, a sensual art form, but is it sexist to be sexy?