Cover headline on this month's Scientific American: "ARE VIRUSES ALIVE?" The answer: Uh, well, er, dunno.
A snippet of RNA or DNA in a protein coat. Dazzlingly beautiful (a model of the SARS virus at right), like invisibly small Christmas-tree ornaments. Can't reproduce without highjacking the chemical machinery of something or someone that is undeniably alive, like you or me.
Were viruses an evolutionary step on the way to life? Or are they renegade genes from living organisms? And WHERE'S MY FLU SHOT?