Rod Rapid and His Electric Chair — John Barnes

A short story originally published in HelixSF. A brain scientist and a policeman desperately try to figure out why one brilliant biologist tricked the world into total ecocide; the clues seem to lie in some of the worst boys' adventure books ever written. A funny story about the death of all multicellular life on Earth, a sad story about someone who just wanted something very simple, and a slightly cracked and goofy story about the terrible power of really trashy reading, even for those of us who know better.