Once again, laziness pays off. When microbiologist Lars Peter Nielsen and his team were studying marine sediments, they got a little sloppy about cleaning their beakers. But after letting samples sit around in the lab for a few weeks, they began to see weird chemical patterns in them that you just wouldn't expect. As they saw changes in the surface of the mud quickly trigger other changes down below, the scientists came upon a startling idea: that the bacteria in the top layer and those deep down were somehow electrically linked. Their paper appears this week in Nature. Specifically, Nielsen saw that hydrogen sulfide buried below the sediment's surface (the stuff that makes it smell bad) was oxidizing and changing color. One problem, though: That shouldn't be happening. Below the sediment surface there is plenty of hydrogen sulfide and carbon for bacteria to consume via oxidation, or removing electrons
[Scientific ...
