As study author Noah Fierer, a microbial ecologist at the University of Colorado at Boulder, told the New York Times, “Our homes are ecosystems that we spend a lot of time in, and so we approached this with a very general question. What type of microbes and fungi do we see in our homes?” As it turns out, the answer is heavily contingent on who is actually in your home.
In conducting their study, Fierer and the team analyzed the dust of 1,200 households across the continental United States. All in all, they found a total of more than 72,000 types of fungi and over 125,000 kinds of bacteria. Yikes. Moreover, the average household (just one household, mind you), boasted more than 5,000 different species of bacteria and around 2,000 species of fungi. So as clean as you may believe yourself and your rooms to be, think again. These buggers are everywhere.
As it turns out, while geographic location doesn’t have too much of an impact on what types of bacteria flourish in a house (the same types were found in both rural homes and urban homes far distant from each other), fungi serve as a better indicator. Said Fierer, “Geography is the best predictor of fungi in your home. The reason is that most fungi blow in from outdoors via soil and leaves.”
But bacteria constitute an extremely useful yardstick for the types of pets you have, and even the number of men versus women living in a house. Homes with cats had more types of certain bacteria species, while homes with dogs favored others. And when it came to gender ratios, it’s all about the B.O. Yes — body odor.
Said NC State biology professor and study co-author Rob Dunn, “We can tell if there are more men than women in a home, for example, because those homes have more armpit bacteria. Seriously.”
Ultimately, researchers feel that this dust-based profile of a home is just a first step in a much more robust final project that may one day help with forensics or allergen research. Said Dunn, “We’re just starting to look at what lives in our homes. These findings are not an exhaustive answer, they’re a first step — and the study highlights just how much we don’t know.”
