Genetics researcher and author Steve Jones speculates on how males got their start, and then presents us with a biological mystery: Why have males hung around so long? Males don't appear to be biologically necessary. In fact, some species, says Steve, have done away with them entirely. But surely males have some use? Steve makes one argument for why we need men ... or at least a freezer full of sperm. NPR's Nell Greenfieldboyce tells us how news of a new technology allowing the extraction of sperm from a man posthumously impacted a grieving New York widow named Leisha.