No, this is not some philsophical treatise. Nature recently published a paper by a French team that discovered a virus that infects another virus. (You probably don’t have access to Nature either, but keep reading, there is hope.)
Wait a minute: Are viruses alive? They can’t reproduce on their own, so, some scientists argue, they are not really alive. Viruses infect living things. Well, then doesn’t a virus infecting a virus imply the host virus is alive?
What is life? Do we have to redefine it, once again, again?
It’s turtles, all the way down, for some of us — but you, Dear Reader, should probably read a good description of the paper, over at Living the Scientific Life.
Oh — the name of the new thing? It’s a satellite virus, sorta, and it looks right, so the team that discovered it calls it “Sputnik.”
Posted by Ed Darrell 
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