A bizarre new study reveals that each city has its own endemic mix of microscopic life. What about your city?
Scientists from Northern Arizona University at Flagstaff have published a new study that suggests our cities aren’t so similar after all. According to a report from UPI, researchers followed microbial communities over the course of more than a year in office buildings in Flagstaff, San Diego and Toronto to discover just how different the local bacteria and fungi could be.
Researchers regularly took samples from three plates installed on the floors, ceilings and walls of numerous buildings throughout the three cities. Each plate contained a mixture of painted drywall, ceiling tile and a rug – all surfaces that would normally be found in a building.
While keeping careful track of environmental conditions like light and humidity levels, the scientists sequenced the DNA present in each plate every four to six weeks. They were surprised to find that the communities that had grown over the study period were almost nothing like each other.
According to J. Gregory Caporaso, an assistant professor of biological sciences at Northern Arizona University, “This was especially interesting because even within each city, the offices we studied differed from each other in terms of size, usage patterns and ventilation systems, suggesting that geography is more important than any of these features in driving the bacterial community composition of the offices within the ranges that we studied.”
The team found that the microbial communities in Flagstaff were considerably more diverse than those found in San Diego or Toronto, but remain unclear as to why this may be.
Another factor that could potentially influence the microbial makeup of office buildings across different cities is the people who work inside. While the genetic analysis of microbes found in each city revealed that only a small percentage of the communities originated from humans, peoples’ activities and what they bring inside could have had an effect on each building’s specific makeup.
A press release from the American Society for Microbiology describing the details of the study can be found here.