With one small tweet, Discover Magazine writer Veronique Greenwood has managed to single-handedly ruin everyone’s day:

That insight stemmed from the work of North Carolina State University biologist Rob Dunn, whose “Wildlife of Our Homes” project Greenwood profiled as part of a sprawling feature on the hordes of microbes that live among us. Dunn and colleagues had volunteers collect swabs from various locations around their home: their toilet, their bed, the fridge, the couch, and others, which were then sent off for testing.

The pillowcase and the toilet seat actually have a lot in common,” says Holly Menninger, the project’s director of public science. In fact, there is so much overlap between the bacterial strains in those two locations that it can be difficult to tell where a particular sample came from.

“There are also plenty of gut microbes in both places,” writes Greenwood. “hich means that the pillows were seeded with what scientists delicately refer to as ‘fecal contamination.’”

The research is a reminder of the microscopic ecosystems that thrive all around us (and even within us)—a reminder that totally won’t affect your ability to fall asleep tonight. Nope. Not one bit.

More from Smithsonian.com:

Want to Be Healthy? Manage Your Microbes Like a Wildlife Park

Antiobiotics May Be Making You Fat