I For One Welcome Our Microbial Overlords

Can the bacteria in our bodies control our behavior in the same way a puppetmaster pulls the strings of a marionette? I tremble to report that this wonderfully creepy possibility may be true. The human body is, to some extent, just a luxury cruise liner for microbes. They board the SS Homo sapiens when we're born and settle into their assigned quarters--the skin, the tongue, the nostrils, the throat, the stomach, the genitals, the gut--and then we carry them wherever we go. Some of microbes deboard when we shed our skin or use the restroom; others board at new ports when we shake someone's hand or down a spoonful of yogurt. Just as on a luxury cruise liner, our passengers eat well. They feed on the food we eat, or on the compounds we produce. While the biggest luxury lines may be able to carry a few thousand people, we ...