I don't think I'm supposed to take any action or feel particularly alarmed after reading about this global mapping of urban subway microorganisms, but it is kind of neat nonetheless. A team of researchers recently spent over 3 years collecting "metagenomic samples" from the transit systems of 60 cities around the world. Everywhere from Stockholm's handrails to Shanghai's subway poles.

The process involved nearly 5,000 samples and the result is this research paper, providing a full atlas of the microbial strains that live throughout our subway systems. Supposedly, none of the findings are anything that we should be worried about though. So carry on riding the subway.

But it is interesting (and very geeky) to note that the researchers discovered something that they are calling a "core urban microbiome." What this means is that they identified 31 different species of bacteria that show up in pretty much all of the cities that they surveyed -- some 97% of their samples.

At the same time, each city, because of things like climate and geography, also has its own microbial profile. In fact, these profiles are so distinctive that the geneticist who lead the study is quoted in the New York Times saying that if you gave him a shoe that was a worn in a particular subway system, he could sequence it and tell you the city with 88% accuracy.

Is this neat or gross?

Photo by Sergey Zolkin on Unsplash