Whether you're intentionally starting your Christmas shopping or you unwittingly get swept into Macy's by a tide of deal-seekers, you may eventually have to face a public restroom. You'll be sharing it not just with your fellow shoppers, but with a whole mess of bacteria species. Luckily, researchers in Colorado have done some digging into that mess so that you can know just who you'll meet behind the "Ladies" or "Gentlemen" sign.
Public restrooms are a great place to find bacteria, as the authors of the new study euphemistically put it, "because of the activities that take place there and the high frequency of use by individuals with different hygienic routines." Furthermore, different neighborhoods within bathrooms probably house different communities of bacteria. To perform a census on these hidden but lively communities, researchers sampled surfaces in six men's rooms and six women's rooms at the University of Colorado, Boulder. Genetic sequencing of these samples told them which species of bacteria were present. Out of all the bacterial types that turned up, there were 19 phyla of bacteria present in every bathroom.
(The fact that the researchers grouped bacteria into phyla is an alarming reminder of how diverse bacteria are. A phylum is a large grouping that can contain thousands of species. Humans, for example, are members of a phylum that contains every other backboned animal on Earth. In bacterial terms, one faucet handle may as well be a whole rainforest.)
