Ross Gelbspan, Pulitzer Prize winner and author of The Heat Is on: The Climate Crisis, the Cover-Up, the Prescription. Also: U.S. government trying to reclaim nuclear devices and uranium that were dispersed around the world during the Cold War; Both human and chimp genomes have been sequenced and are being compared: Is it possible to genetically model the "Missing Link"? Scientists find key area of cell implicated in the aging process; Immigrants in the U.S. live longer than US-born; Scientists find youngest planet yet.